Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Heterocyclic Chemistry  

DOI： 10.3987/com-23-14810

researchmap

Publishing type：Research paper (scientific journal)   Publisher：The Japan Institute of Heterocyclic Chemistry  

DOI： 10.3987/com-23-14849

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Nucleophilic substitution of hexachlorocyclotriphosphazene (HCCP) with arylthiol gave 2,2-bis(arylthio)-4,4,6,6-tetrachlorocyclotriphosphazene. Aminolysis of 2,2,4,4-teterachloro-6,6-bis(4-methoxyphenylthio)cyclotriphosphazene with gaseous ammonia gave gem-di substituted 2,2-diamino-4,4-dichloro-6,6-bis(4-methoxyphenylthio)cyclotriphosphazene in Et20 and tetrasubstituted 2,2,4,4-tetraamino-6,6-bis(4-methoxyphenylthio)- cyclotriphosphazene in acetonitrile, respectively. The reaction of 2,2,4,4-teterachloro-6,6-bis(4-methoxyphenylthio)cyclotriphosphazene with 4-chlorophenol gave a mixture of gem-disubstituted 2,2-dichloro-4,4-bis(4-chlorophenoxy)-6,6-bis(4-methoxyphenylthio)cyclotriphosphazene and tetrasubstituted 2,2,4,4-tetrakis(4-chlorophenoxy)-6,6-bis(4-methoxyphenylthio)cyclotriphosphazene, whose ratio depended on the reaction solvent. On the other hand, in reaction of 2,2-bis(arylthio)-4,4,6,6-tetrachlorocyclotriphosphazene with another arylthiol, ArS-groups were scrambled.

DOI： 10.3987/COM-21-14510

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Hexachlorocyclotriphosphazene (HCCP) is a very old compound, and used as a starring material of a variety of cyclotriphosphazene derivatives. Some of them have unique properties, and have been used in not only frame retardants but also functional materials and biomaterials. To develop cyclotriphosphazene derivatives having a desired function, numbers of substituents, regio-, and stereochemistry should be controlled in the reaction between HCCP and nucleophiles. In this review, selectivity in the reaction between HCCP and nucleophiles as well as application of the cyclotriphosphazene derivatives are summarized.

DOI： 10.3987/REV-19-924

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Electrooxidation of MeCN solution of chlorodiphenylphosphine in the presence of Cl- under NH3 atmosphere gave a mixture of 2,2,4,4 ,6,6-hexaphenyl cyclotriphosphazene and iminobis(aminodiphenyl- phosphorus) chloride.

DOI： 10.3987/COM-19-14150

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We investigated the reaction between hexachlorocyclotriphosphazene ((NPCl2)(3): HCCP) and thiols in the presence of bases. In MeCN/Et3N, two and/or four arylthio units were introduced in gem-mode selectively by controlling the amount of thiols: thus, HCCP was treated with 2 and/or 4 equivalents of ArSH/Et3N in MeCN to afford 2,2-dithiolated and/or 2,2,4,4-tetrathiolated products, respectively. Neither mono-thiosubstituted products, tri-thiosubstituted products, nor regioisomers (non-geminal products) were obtained. In contrast, when other solvents such as THE and Et2O or other bases such as NaH or K2CO3 were used, a mixture of dithiolated products, tetrathiolated products, and hexathiolated products was obtained.

DOI： 10.3987/COM-19-14100

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

We investigated the reaction between hexachlorocyclotriphosphazene ((NPCl2)(3)) and gaseous ammonia in several solvents to find that (NPCl2)(2)(NP(NH2)(2)) was obtained in solvents having low dielectric constant such as toluene and ether, whereas novel compound, (NPCl2)(NP(NH2)(2))(2), was selectively obtained in solvents having high dielectric constant such as acetonitrile.

DOI： 10.3987/COM-19-14099

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

Objective. The functional monomer 10-MDP has been considered as one of the best performing functional monomers for dental adhesives. Different adhesives containing 10-MDP are commercially available, among which many so-called 'universal' adhesives. We hypothesize that the quality of the functional monomer 10-MDP in terms of purity may affect bonding performance.Methods. We therefore characterized three different 10-MDP versions (10-MDP_KN provided by Kuraray Noritake; 10-MDP_PCM provided by PCM; 10-MDP_DMI provided by DMI) using NMR, and analyzed their ability to form 10-MDP_Ca salts on dentin using XRD. The 'immediate' and 'aged' micro-tensile bond strength (mu TBS) to dentin of three experimental 10-MDP primers was measured. The resultant interfacial adhesive-dentin ultra-structure was characterized using TEM.Results. NMR disclosed impurities and the presence of 10-MDP dimer in 10-MDP_PCM and 10-MDP_DMI. 10-MDP_PCM and 10-MDP_DMI appeared also sensitive to hydrolysis. 10-MDP_KN, on the contrary, contained less impurities and dimer, and did not undergo hydrolysis. XRD revealed more intense 10-MDP_Ca salt deposition on dentin induced by 10-MDP_KN. The adhesive based on the experimental 10-MDP_KN primer resulted in a significantly higher 'immediate' bond strength that remained stable upon aging; the mu TBS of the experimental 10-MDP_PCM and 10-MDP_DMI adhesives significantly dropped upon aging. TEM revealed thicker hybridization and more intense nano-layering for 10-MDP_KN.Significance. It was concluded that primer impurities and the presence of 10-MDP dimer affected not only hybridization, but also reduced the formation of 10-MDP_Ca salts and nano-layering. 10-MDP in a high purity grade is essential to achieve durable bonding. (C) 2015 Published by Elsevier Ltd on behalf of Academy of Dental Materials. All rights reserved.

DOI： 10.1016/j.dental.2015.09.019

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Direct reductions of phosphine oxides to the corresponding phosphines were performed successfully by using Mg/Me3SiCl/DMI system. The reduction proceeded under mild conditions and was applicable to a wide range of phosphine oxides; triarylphosphine oxides, alkyldiarylphosphine oxides, and dialkylarylphosphine oxides gave the corresponding phosphines in good to excellent yields. (C) 2015 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2014.12.132

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Electroreduction of diquat triflate gave a potent organic reductant, which promoted reductive dimerization of aryl bromides in the presence of palladium catalysts to give the corresponding biaryl compounds.
This manuscript is dedicated to the celebration of the 77th birthday of Prof. Isao Kuwajima, Professor emeritus of Tokyo Institute of Technology.

DOI： 10.3987/COM-14-S(K)53

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：TAYLOR & FRANCIS INC  

Diethyl azodicarboxylate (DEAD) is a well-known coupling reagent that can be readily synthesized from diethylhydrazodicarboxylate (DEHD). The bromination of commercially available ethyl allophanate (1) in CHCl3, followed by the Hofmann-type rearrangement reaction of the resulting N-brominated species 2 and 3 in C2H5OH in the presence of 1,8-diazabicyclo[5.4.0]-7-undecene (DBU), gave DEHD in good yield from a one-pot process. Interestingly, however, the bromination and Hofmann-type rearrangement reactions did not occur in the presence of N(C2H5)(3). These results therefore suggest that this reaction is reliant upon a high level of reactivity during the bromination reaction to give 2 and 3, and that these N-brominated species require the presence of a strong and nonnucleophilic base to undergo the Hofmann-type rearrangement to give DEHD.

DOI： 10.1080/00397911.2014.1002137

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode, wherein Al(3+), which was electrogenerated at the anode would react as a Lewis acid with triphenylphosphine dichloride to afford tetra-coordinate chlorotriphenylphosphonium species and subsequent two-electron reduction at the cathode would give triphenylphosphine. One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide with oxalyl chloride and subsequent electroreduction. In a similar manner, some tetra-coordinate triphenylphosphonium species derived from triphenylphosphine oxide were reduced electrochemically to triphenylphosphine in moderate yields. (C) 2011 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2011.05.044

Web of Science

researchmap

Language：English   Publishing type：Research paper (scientific journal)   Publisher：GEORG THIEME VERLAG KG  

Direct reductive transformation of triphenylphosphine oxide to triphenylphosphine was performed successfully by electrolysis with TMSCl in an acetonitrile/Bu4NBr/(Zn anode)-(Pt cathode)/undivided cell/constant current electrolysis system. A plausible ECEC mechanism involving the formation of silylated phosphorus radical is proposed.

DOI： 10.1055/s-0030-1259529

Web of Science

researchmap

Publisher：Wiley-Blackwell  

DOI： 10.1002/chin.200609212

researchmap

Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：SOC SYNTHETIC ORGANIC CHEM JPN  

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Electroreduction of triphenylphosphine oxide to triphenylphosphine in an acetonitrile solution of tetrabutylammonium bromide in the presence of chlorotrimethylsilane was performed successfully in an undivided cell fitted with a zinc anode and a platinum cathode under constant current. A plausible mechanism involving, (1) one-electron reduction of triphenylphosphine oxide generating the corresponding anion radical [Ph(3)P(center dot)-O(-)], (2) subsequent reaction with chlorotrimethylsilane affording the (trimethylsiloxy)triphenylphosphorus radical [Ph(3)P(center dot)-OSiMe(3)], and (3) further one-electron reduction followed by P-O bond fission leading to triphenylphosphine is proposed. In a similar manner, electroreduction of some triarylphosphine oxides and alkyldiarylphosphine oxides was executed to give the corresponding phosphine derivatives in good to moderate yields.

DOI： 10.1055/s-0031-1289612

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

One-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved by the reaction of triphenylphosphine oxide with oxalyl chloride, which led to the formation of triphenylphosphine dichloride, and subsequent reduction of triphenylphosphine dichloride with a combination of aluminum-catalytic metal salt.

DOI： 10.1055/s-0029-1219194

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Electroreduction of triphenylphosphine dichloride in acetonitrile was performed successfully in an undivided cell fitted with an aluminium sacrificial anode and a platinum cathode. Further, the one-pot transformation of triphenylphosphine oxide to triphenylphosphine was achieved successfully by the treatment of triphenylphosphine oxide in acetonitrile with oxalyl chloride and subsequent electrochemical reduction. (C) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2009.11.115

Web of Science

researchmap

Language：English   Publisher：ELECTROCHEMICAL SOC JAPAN  

Halide ion-promoted desulfo-halogenation was applied successfully to synthesis of 4-chloro-2-azetidinone 1, a potent intermediate for carbapenem synthesis. and stereoselective N-glycosylation of 2,3-deoxyglycosides. Bromide ion/N-oxyl compounds (TEMPO) double mediatory systems enabled us to develop several aqueous electrolysis media free from organic solvents, e.g., silica gel or polymer particles/water disperse systems and water-soluble TEMPO-mediated oil-in-water emulsion systems, in which electrooxidation of alcohols was carried out successfully in a simple beaker-type undivided cell under a constant current condition. Notably, the work-up process was very simple and the solid particles (disperse phase) and the aqueous solutions (disperse media) were easily recovered and reused, offering a totally closed system. In Pd(OAc)(2)/TEMPO double mediatory systems, electrogeneration of active cationic palladium catalysts was integrated into electrooxidative Wacker-type reaction. In a similar manner, Wacker-type cyclization and homo-coupling of arylboronic acids were successfully achieved.

DOI： 10.5796/electrochemistry.77.1002

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Electrolysis of 3-arylthiomethyl-Delta(3)-cephems possessing various substituents on the arylthio moiety undergo chemoselective and product-selective electrooxidation to give several different products. These include isomeric mixtures of the corresponding methoxylated cephems, a bis[(Delta(3)-cephem-3-yl)methyl]disulfide or a 3-dimethoxymethyl-Delta(3)-cephem. The selectivity of the oxidation is highly dependent on the nature of the substituents on the arylthio moiety which suggests that both steric and electronic effects play an important role in the electrooxidation 3-arylthiomethyl-Delta(3)-cephems.

DOI： 10.1055/s-0029-1216972

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Oil-in-water nanoemulsion which consisted of TEMPO, amphiphilic alcohols, and water offered unique reaction environments for electrooxidation of the alcohols to give the corresponding carboxylic acids in good to excellent yields. (c) 2009 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2009.06.005

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Electrooxidation of-alcohols in a disperse system with N-oxyl-immobilized silica gel as a disperse phase and an aqueous NaBr/NaHCO(3) solution as a disperse medium proceeded smoothly to give the corresponding carbonyl compounds. The N-oxyl-immobilized silica gel 1 was prepared by silane-coupling method. Recycling of both the aqueous Solution and the N-oxyl-immobilized silica gel 1 was performed successfully.

DOI： 10.1055/s-0028-1087987

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Electroreduction of N,N'-dioctyl-4,4'-bipyridinium bis(tri-flimide) [C(8)V(2+)][Tf(2)N(-)](2) in THF gave a dark blue solution of the corresponding quinoid C(8)V(0), which worked as an efficient organic reductant for Pd-catalyzed reductive coupling of aryl bromides to give the corresponding biphenyl derivatives in good yields. After usual workup, [C(8)V(2+)][Tf(2)N(-)](2) was recovered and reused for generation of the organic reductant C(8)V(0).

DOI： 10.1055/s-2008-1087386

Web of Science

researchmap

Language：Japanese  

CiNii Article

CiNii Books

researchmap

Language：English   Publisher：ELECTROCHEMICAL SOC JAPAN  

Electroreduction of N,N'-dioctyl-4,4'-bipyridinium (C8V2+) bis(triflimide) was carried out in ionic liquids to give the corresponding quinoid C8V0, which promoted reductive coupling of aryl halides in the presence of a Pd catalyst to give biaryls. C8V2+ and the ionic liquids were used repeatedly.

DOI： 10.5796/electrochemistry.76.862

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

(3S,4R)-3-(1'(R)-tert-Butyldimethylsilyloxyethyl)-4-chloro-2-azetidinone (2), a potent intermediate for the synthesis of carbapenem antibiotics, was synthesized by thermal ring opening/acylation of (3S,5R,6S)-6-(1'(R)-tert-butyldimethylsilyloxyethyl)penicillanate S-oxide (8) leading to 4-acylthio-2-azetidinone derivative 9 and subsequent removal of the N-substituent followed by electrooxidative desulfurization/chlorination of the C(4)-acylthio moiety.

DOI： 10.3987/COM-08-S(N)110

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Grignard reagent-promoted coupling reaction of diphenylmethyl 6,6-dibromopenicillanate 1b with acetaldehyde in the presence of N,N,N',N",N"-pentamethyldiethylenetriamine took place in a highly diastereoselective manner to give diphenylmethyl (1'R,3S,5R,6S)-6-bromo-6-(1'-hydroxyethyl)penicillanate 2b effectively, which is a potent intermediate for the synthesis of carbapenem antibiotics.

DOI： 10.3987/COM-07-S(U)47

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Oil-in-water nanoemulsions, consisting of TEMPO, amphiphilic alcohols, and water, offer unique reaction environments for electrooxidation of the alcohols to give the corresponding carboxylic acids in good to excellent yields.

DOI： 10.1055/s-2007-991070

Web of Science

researchmap

Language：English   Publisher：ELECTROCHEMICAL SOC JAPAN  

Electrolysis of 2-azetidinone 3 in AcOH/CH3CN containing NaBr (2-10 equiv.) was carried out in an undivided cell fitted with two platinum electrodes to afford the corresponding N-bromo-2-azetidinones 2a, while a similar electrolysis in a divided cell afforded no appreciable amount of 2 but a small amount of 4-acetoxy-2-azetidinone I together with a complex mixture. Ring-expansion of 2-azetidinone 3 leading to 4 took place exclusively by electrolysis in methanol containing AcONa. On the other hand, N-iodination proceeded efficiently only in a divided cell in the presence of 2.5 equiv. of NaI. Reaction of N-bromo-2-azetidinone 2 with various nucleophiles, e.g., acetate, thiolate, and alkoxides, afforded no substitution products, resulting in the reductive debromination leading to 3, whereas with diphenyl disulfide, N-phenylsulfenyl-2-azetidinone 5 was mainly obtained.

DOI： 10.5796/electrochemistry.74.656

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

The electrooxidation of alcohols in an aqueous disperse system with N-oxyl-immobilized poly(p-phenylene benzobisthiazole) network polymer particles (PBZT(NT)-N-Oxyl) as a disperse phase was performed successfully in a simple beaker-type undivided cell tinder a constant current condition to afford the corresponding ketones, aldehydes, and/or carboxylic acid in moderate to good yields. Recycle use of both the PBZT(NT)-N-Oxyl particles and the aqueous media could be achieved successfully by immobilization of additional N-oxyl moiety on the polymer particles in an appropriate interval. Notably, the shape and the particle size of PBZT(NT)-N-Oxyl were not appreciably changed even after 60 times recycle use. (c) 2006 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tet.2006.03.020

Web of Science

researchmap

Language：English   Publisher：AMER CHEMICAL SOC  

The electrooxidative glycosylation of newly designed 1-arylthio-substituted 2,3-dideoxyglycosides is described. The halide salt-mediated electrooxidation utilizing either of the alpha- or beta-thiodideoxyglycosides proceeded smoothly at -78 degrees C to give dideoxynucleosides in beta-selective manner, presumably through a 1-halo-substituted glycosyl donor.

DOI： 10.1021/ol0521776d

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

The electrooxidation of alcohols in a disperse system with N-oxyl-immobilized polymer particles (PE-co-AA-N-Oxyl), prepared from poly(ethylene-co-acrylic acid) (PE-co-AA-Co2H), as a disperse phase and an aqueous saturated NaHCO3 containing 20 wt % NaBr as a disperse medium was successfully performed in a simple beaker-type undivided cell under constant-current conditions. The electrooxidation of alcohols proceeded in a similar manner by the use of PEco-AA-CO2H as a disperse phase, though the current efficiency decreased in some extent. Protection of most of the carboxylic acid moieties on the surface of PE-co-AA-CO2H by esterification or amidation resulted in significant decrease of the product yields, suggesting that the carboxylic acid moieties on the surface of PE-co-AA-CO2H would also act as a mediator for the electrooxidation of alcohols. Both the recovered PE-co-AA-N-Oxyl and the aqueous solution were used repeatedly for the electrooxidation of alcohols, thereby offering a formally closed system for the electrooxidation of alcohols.

DOI： 10.1246/bcsj.78.1677

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Pd/TDAE-promoted reductive coupling of aryl bromides (Ar-Br) proceeded in ionic liquids, e.g., BdmimBF(4) and BdmimTf(2)N, to afford the corresponding symmetric biaryls (Ar-Ar) in good yields. Proper choice of ionic liquids and Pd catalysts is indispensable. Recycle use of BdinimTf(2)N and Pd catalyst was performed successfully.

DOI： 10.1246/cl.2005.530

Web of Science

researchmap

Language：English   Publisher：ELECTROCHEMICAL SOC JAPAN  

N-Oxyl-mediated electrooxidation of see-alcohols in ionic liquids was performed successfully to give the corresponding ketones. By use of ionized N-oxyl, [TEMPOmim] [Tf2N], both the ionic liquids and the N-oxyl compound could be recovered and reused for the electrooxidation of alcohols.

Web of Science

researchmap

Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：CHEMICAL SOC JAPAN  

The oxidation of alcohols was performed successfully in a disperse system with N-oxyl-adsorbed or immobilized silica gel as a disperse phase and aqueous NaOCl as a disperse medium. In the disperse system, the oxidation of sec-alcohols afforded the corresponding ketones, while prim-alcohols were oxidized to aldehydes and/or carboxylic acids depending on their structures and reaction conditions. The N-oxyl-immobilized silica gel was recovered and repeatedly used without a significant change in the product yields. A column-flow system was also investigated for the oxidation of alcohols by use of a newly devised column packed with the N-oxyl-immobilized silica gel.

DOI： 10.1246/bcsj.77.1745

Web of Science

researchmap

Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：BENTHAM SCIENCE PUBL LTD  

Aluminum (Al) is an ideal reducing agent (electron pool) since it is cheap, easy to handle, able to release enough electron (3 e(-)/atom), and environment friendly. However, the use of A] in organic synthesis is rather limited owing to lack of efficient electron transfer process between Al and organic substances. In last decay, we and some other groups developed multi-redox promoted reactions using Al as a terminal reductant in which Al act as an electron pool and a catalytic amount of metal salt(s) works as a mediator for electron transfer from Al to substrates. Indeed, various combinations of A] and metal salt(s), e.g., Al/PbBr2, A]/PbBr2/AlBr3, Al/NiCl2/CrCl2, Al/PbBr2/TFA, Al/PbBr2/NiCl2(bpy), etc., have been developed to promote carbon-carbon bond formation as well as highly selective functionalization. Further more, these multi-redox promoted reactions have been successfully utilized for the synthesis of useful compounds, such as beta-lactam antibiotics and beta-lactamase inhibitors. This review article will summarize the recent progress in the multi-metal redox promoted reactions using A) as an electron pool and their applications to organic synthesis.

DOI： 10.2174/1385272043370320

Web of Science

researchmap

researchmap

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

Electrooxidation of alcohols was performed successfully in a disperse system with N-oxyl immobilized polyethylene particles as disperse phase and an aqueous saturated NaHCO3 solution involving 20 wt% NaBr as disperse media. The N-oxyl immobilized polyethylene particles were prepared by heating a suspension of polyethylene particles (3 x 3 x 0.02 mm(3)) in fuming nitric acid at 80 degreesC for 1 h followed by treatment with 4-amino-2,2,6,6-tetramethylpyperidine- 1-oxyl in chlorobenzene in the presence of DCC. Recycle use of the N-oxyl-immobilized polyethylene particles and the aqueous media was performed successfully without significant change of the yields of the products and current efficiency, thereby offering a totally closed electrolysis system.

Web of Science

researchmap

Language：English   Publisher：AMER CHEMICAL SOC  

Tetrakis(dimethylamino)ethylene (TDAE)/cat. PdCl2(PhCN)(2)-promoted reductive coupling of aryl bromides having either electron-donating or electron-withdrawing groups on their para- and/or meta-position proceeded smoothly to afford the corresponding biaryls in good to excellent yields. Notably, TDAE is such a mild reductant that easily reducible groups, such as carbonyl and nitro groups, are tolerate. A similar reductive coupling of ortho-substituted aryl bromides did not occur at all. The proper choice of palladium catalysts is essential for the reductive coupling; thus, PdCl2(PhCN)(2), PdCl2(MeCN)(2), Pd(hfacac)(2), Pd-2(dba)(3), PdCl2, and Pd(OAc)(2) were used successively for this reaction, but phosphine-ligated palladium catalysts such as Pd(PPh3)(4), PdCl2(PPh3)(2), and Pd(dppp) did not promote the reaction. The reductive coupling did not occur with nickel catalysts such as NiBr2, NiCl2(bpy), and Ni(acac)(2). The TDAE/cat. palladium-promoted reductive coupling of aryl halides having electron-withdrawing groups took place more efficiently than that of aryl halides substituted with electron-donating groups. A plausible mechanism of TDAE/cat. palladium-promoted reaction is discussed.

DOI： 10.1021/jo0207473

Web of Science

researchmap

researchmap

researchmap

Language：English   Publisher：GEORG THIEME VERLAG KG  

A combination of tetrakis(dimethylamino)ethylene (TDAE) and palladium catalysts promoted reductive homo-coupling of aryl halides efficiently to afford the corresponding biaryls in good to quantitative yields. TDAE acted as a very mild reductant, and easily reducible functional groups, such as a nitro, formyl, ester, or nitrite group, remained unchanged.

Web of Science

researchmap

researchmap

Language：English   Publisher：ELSEVIER SCIENCE SA  

Enantioselective electro-epoxidation of olefins by using an optically active Mn-salen complex, (S,S)-N,N ' -bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III)chloride (3), as a mediator in a CH2Cl2 aqueous NaCl two-phase system was performed successfully in a simple undivided cell under constant current conditions. Optimization of the electrolysis conditions and estimation of the reaction mechanism are discussed. (C) 2001 Elsevier Science B.V. All rights reserved.

DOI： 10.1016/S0022-0728(01)00387-4

Web of Science

researchmap

Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：WILEY-V C H VERLAG GMBH  

The oxidative desulfurization-fluorination reaction of organosulfur compounds using an N-haloimide and a fluoride source is demonstrated to be an effective and mild fluorination method that allows us to synthesize in high yields with high chemoselectivity various types of gem-difluoro compounds, trifluoromethyl-substituted (hetero)-aromatics, trifluoromethyl ethers, and N-trifluoromethylanilines. Herein briefly summarized are the synthetic procedures as well as the scape and limitations of the. reaction. The applicability of the reaction is demonstrated by the synthesis of a difluorinated glutamic acid and novel liquid-crystalline materials having an N-trifluoromethylamino, trifluoromethoxy, or 1,2-difluoroethylene group. The fluorine-containing liquid-crystalline materials are compared with the corresponding non-fluorinated materials in respect to phase transition behaviors and electro-optical properties and shown to be suitable for not only super twisted nematic (STN) but also for thin film transistor (TFT)-addressed liquid crystals displays.

Web of Science

researchmap

Language：English   Publisher：Faculty of Engineering, Okayama University  

CiNii Article

CiNii Books

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Regioselective electro-bromination of benzofuran (2) was achieved successfully by an adequate choice of solvents and bromide salts to afford 5-bromobenzofuran (1), 5,7-dibromobenzofuran (3), and 2,3-dibromo-2,3-dihydrobenzofuran (4), respectively. Upon electrolysis of benzofuran (2) in AcOH/H2O (100/1) containing NH4Br, substitution at the C(5)-position of benzofuran (2) proceeded smoothly to afford 5-bromobenzofuran (1). After passage of totally 4 F/mol of electricity in a similar medium, 5,7-dibromobenzofuran (3) was obtained as a sole product. On the other hand, electrolysis of benzofuran (2) in CH2Cl2/H2O (1/1) and/or AcOH/H2O (10/1) in the presence of either NaBr or NH4Br afforded 2,3-dibromo-2,3-dihydrobenzofuran (4), exclusively.

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

N-Oxyl-mediated electrooxidation of alcohols was performed in an aqueous silica gel disperse system. The newly devised electrolysis system offers an organic solvent-free and operationally simple procedure for oxidation of alcohols and could be successfully applied to kinetic resolution of sec-alcohol as well as enantioselective oxidation of meso-1,4-diol affording optically active gamma -lactone. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)01979-1

Web of Science

researchmap

researchmap

researchmap

researchmap

researchmap

Language：Japanese   Publishing type：Book review, literature introduction, etc.   Publisher：CHEMICAL SOC JAPAN  

The oxidative desulfurization-fluorination reaction of organosulfur compounds using an N-halo imide and a fluoride source is demonstrated to be an effective and mild fluorination method that allows to synthesize various types of organofluorine compounds containing a difluoromethylene unit, tri fluoromethyl-substituted aromatics, trifluoromethyl ethers, and N-trifiuoromethylamines in high yields with high chemoselectivity. Herein briefly summarized are the synthetic procedures for such organofluorine compounds and scope and limitations of the reaction. The reaction is applied to the synthesis of novel liquid-crystalline materials having a fluorine functional group such as an N-trifluoromethylamino, trifluoromethoxy, or 1,2-difluoroethylene group. The fluorine-containing liquid-crystalline materials are compared with the corresponding non-fluorinated materials in respect to phase transition behaviors and electro-optical properties. The novel fluorine-containing liquid crystals are shown to be suitable for not only super twisted nematic (STN) but also thin film transistor (TFT) -addressed liquid crystal displays.

Web of Science

researchmap

Language：English  

Electro-oxidative kinetic resolution of sec-alcohols mediated with a catalytic amount of an optically active N-oxyl was performed by use of a simple undivided cell under constant current conditions. The selectivity factor (S-value) increased remarkably when the reaction was performed at lower temperatures. The optically active N-oxyl was recovered and used repeatedly without any change in efficiency and selectivity. © 2000 Elsevier Science Ltd.

DOI： 10.1016/S0040-4039(00)01419-2

Scopus

researchmap

Language：English  

Electro-oxidative kinetic resolution of sec-alcohols mediated with a catalytic amount of an optically active N-oxyl was performed by use of a simple undivided cell under constant current conditions. The selectivity factor (S-value) increased remarkably when the reaction was performed at lower temperatures. The optically active N-oxyl was recovered and used repeatedly without any change in efficiency and selectivity. © 2000 Elsevier Science Ltd.

DOI： 10.1016/S0040-4039(00)01419-2

Scopus

researchmap

Language：English  

Electro-oxidative kinetic resolution of sec-alcohols mediated with a catalytic amount of an optically active N-oxyl was performed by use of a simple undivided cell under constant current conditions. The selectivity factor (S-value) increased remarkably when the reaction was performed at lower temperatures. The optically active N-oxyl was recovered and used repeatedly without any change in efficiency and selectivity. © 2000 Elsevier Science Ltd.

DOI： 10.1016/S0040-4039(00)01419-2

Scopus

researchmap

Language：English  

Electro-oxidative kinetic resolution of sec-alcohols mediated with a catalytic amount of an optically active N-oxyl was performed by use of a simple undivided cell under constant current conditions. The selectivity factor (S-value) increased remarkably when the reaction was performed at lower temperatures. The optically active N-oxyl was recovered and used repeatedly without any change in efficiency and selectivity. © 2000 Elsevier Science Ltd.

DOI： 10.1016/S0040-4039(00)01419-2

Scopus

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Electro-oxidative kinetic resolution of sec-alcohols mediated with a catalytic amount of an optically active N-oxyl was performed by use of a simple undivided cell under constant current conditions. The selectivity factor (S-value) increased remarkably when the reaction was performed at lower temperatures. The optically active N-oxyl was recovered and used repeatedly without any change in efficiency and selectivity. (C) 2000 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(00)01419-2

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Trifluoromethyl ethers R-OCF3 are easily synthesized from the corresponding dithiocarbonates R-OCS2Me (R = aryl or primary alkyl) by a reagent system consisting of 70% HF/pyridine and an N-halo imide. When the reaction is applied to R-OCS2Me wherein R = secondary alkyl, tertiary alkyl, or benzylic group, fluorination leading to the corresponding alkyl fluorides R-F is achieved, whereas a combination of 50% HF/pyridine and N-bromosuccinimide affords the corresponding trifluoromethyl ethers R-OCF3 (R = secondary).

DOI： 10.1246/bcsj.73.471

Web of Science

researchmap

Language：English  

Trifluoromethyl ethers R-OCF3 are easily synthesized from the corresponding dithiocarbonates R-OCS2Me (R = aryl or primary alkyl) by a reagent system consisting of 70% HF/pyridine and an N-halo imide. When the reaction is applied to R-OCS2Me wherein R = secondary alkyl, tertiary alkyl, or benzylic group, fluorination leading to the corresponding alkyl fluorides R-F is achieved, whereas a combination of 50% HF/pyridine and N- bromosuccinimide affords the corresponding trifluoromethyl ethers R-OCF3 (R = secondary).

DOI： 10.1246/bcsj.73.471

Scopus

researchmap

Language：English  

Trifluoromethyl ethers R-OCF3 are easily synthesized from the corresponding dithiocarbonates R-OCS2Me (R = aryl or primary alkyl) by a reagent system consisting of 70% HF/pyridine and an N-halo imide. When the reaction is applied to R-OCS2Me wherein R = secondary alkyl, tertiary alkyl, or benzylic group, fluorination leading to the corresponding alkyl fluorides R-F is achieved, whereas a combination of 50% HF/pyridine and N- bromosuccinimide affords the corresponding trifluoromethyl ethers R-OCF3 (R = secondary).

DOI： 10.1246/bcsj.73.471

Scopus

researchmap

Language：English   Publisher：Elsevier Ltd  

Tetrakis(dimethylamino)ethylene (TDAE) was found to be a potent organic electron source which could promote alkenylation of several kinds of aldehydes in the presence of a catalytic amount of NiBr2 and CrCl3.

DOI： 10.1016/S0040-4039(99)02006-7

Scopus

researchmap

Language：English   Publisher：Elsevier Ltd  

Tetrakis(dimethylamino)ethylene (TDAE) was found to be a potent organic electron source which could promote alkenylation of several kinds of aldehydes in the presence of a catalytic amount of NiBr2 and CrCl3.

DOI： 10.1016/S0040-4039(99)02006-7

Scopus

researchmap

Language：English   Publisher：Elsevier Ltd  

Tetrakis(dimethylamino)ethylene (TDAE) was found to be a potent organic electron source which could promote alkenylation of several kinds of aldehydes in the presence of a catalytic amount of NiBr2 and CrCl3.

DOI： 10.1016/S0040-4039(99)02006-7

Scopus

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Tetrakis(dimethylamino)ethylene (TDAE) was found to be a potent organic electron source which could promote alkenylation of several kinds of aldehydes in the presence of a catalytic amount of NiBr2 and CrCl3. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)02006-7

Web of Science

researchmap

DOI： 10.1246/nikkashi.2000.749

researchmap

Language：English   Publisher：GEORG THIEME VERLAG  

A new combination of organic reductant, tetrakis(dimethylamino)ethylene, and transition metal catalysts is reported for allylation of aldehydes and ketones.

Web of Science

researchmap

Language：English   Publisher：ELSEVIER SCIENCE SA  

Double allylation of carboxylic esters with allyl bromide was performed successfully by the action of aluminum metal and a catalytic amount of lead(II) bromide in tetrahydrofuran (THF). The proper choice of solvent is essential for the reaction; thus, among the examined solvents, ethers, e.g. THF, 1,2-dimethoxyethane (DME), and diethyl ether, could be successfully used for the double allylation but with N,N-dimethylformamide (DMF), aqueous MeOH, and aqueous THF, no appreciable reaction occurred. Allylation of benzaldehyde dimethyl acetal and N-benzylimine in THF under the same conditions took place smoothly to afford the corresponding allylation products. In a similar manner, allylation of benzonitrile was also performed to afford the doubly allylated benzylamine. (C) 1999 Elsevier Science S.A, All rights reserved.

DOI： 10.1016/S0020-1693(99)00393-X

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Liquid crystals (LCs) containing a trifluoromethylamino group are prepared by the cross-coupling reaction of p-bromo-substituted-(hetero)aryl(trifluoromethyl)amines that are derived from the corresponding dithiocarbamates through oxidative desulfurization-fluorination. The novel LCs are shown to exhibit mainly a smectic phase over a wide range of temperatures. Their electro-optical properties as a component of nematic LCs are compared with those of the corresponding methylamines.

DOI： 10.1246/bcsj.72.2523

Web of Science

researchmap

Language：English   Publisher：Elsevier  

A convenient synthetic method is described for 3-substituted aromatic trifluoromethyl ethers through an oxidative desulfurization-fluorination reaction. Upon addition to liquid crystalline materials, these ethers lower birefringence (Δn) of the host liquid crystals.

DOI： 10.1016/S0022-1139(99)00049-4

Scopus

researchmap

Language：English   Publisher：Elsevier  

A convenient synthetic method is described for 3-substituted aromatic trifluoromethyl ethers through an oxidative desulfurization-fluorination reaction. Upon addition to liquid crystalline materials, these ethers lower birefringence (Δn) of the host liquid crystals.

DOI： 10.1016/S0022-1139(99)00049-4

Scopus

researchmap

Language：English   Publisher：ELSEVIER SCIENCE SA  

A convenient synthetic method is described for 3-substituted aromatic trifluoromethyl ethers through an oxidative desulfurization-fluorination reaction. Upon addition to liquid crystalline materials, these ethers lower birefringence (Delta n) of the host liquid crystals. (C) 1999 Elsevier Science S.A. All rights reserved.

DOI： 10.1016/S0022-1139(99)00049-4

Web of Science

researchmap

Language：English  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1016/S0040-4039(99)00294-4

Scopus

researchmap

Language：English  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1016/S0040-4039(99)00294-4

Scopus

researchmap

Language：English  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1016/S0040-4039(99)00294-4

Scopus

researchmap

Language：English  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1016/S0040-4039(99)00294-4

Scopus

researchmap

Language：English  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1016/S0040-4039(99)00294-4

Scopus

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Trifluoromethyl-substituted aromatic compounds were easily synthesized by the oxidative desulfurization-fluorination reaction of readily accessible methyl arenecarbodithioates using [n-Bu4N]H2F3 and 1,3-dibromo-5,5-dimethylhydantoin (DBH) under extremely mild conditions. Use of N-bromosuccinimide or N-iodosuccinimide instead of DBH afforded di fluoro(methylthio)methyl-substituted aromatics. In a similar way, 3,3,3-trifluoropropenyl-substituted aromatic compounds were readily prepared from the corresponding alpha,beta-unsaturated carbodithioates.

DOI： 10.1246/bcsj.72.805

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

Alkenylation of aldehydes mediated by a catalytic amount of Cr(II)/Ni(0), using aluminium as an electron source, was performed to afford the corresponding allyl alcohol derivatives in good to moderate yields. (C) 1999 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(99)00294-4

Web of Science

researchmap

Language：English  

Trifluoromethyl-substituted aromatic compounds were easily synthesized by the oxidative desulfurization-fluorination reaction of readily accessible methyl arenecarbodithioates using [n-Bu4N]H2F3 and 1,3-dibromo-5,5- dimethylhydantoin (DBH) under extremely mild conditions. Use of N- bromosuccinimide or N-iodosuccinimide instead of DBH afforded difluoro(methylthio)methyl-substituted aromatics. In a similar way, 3,3,3- trifluoropropenyl-substituted aromatic compounds were readily prepared from the corresponding α,β-unsaturated carbodithioates.

DOI： 10.1246/bcsj.72.805

Scopus

researchmap

Language：English   Publisher：GEORG THIEME VERLAG  

Electrochemical alkenylation of aldehydes using an Al sacrificial anode in the presence of Cr(II)/Ni(II) catalysts afforded the corresponding allyl alcohol derivatives in good to moderate yields.

Web of Science

researchmap

DOI： 10.1246/bcsj.71.1939

researchmap

Language：English   Publisher：ROYAL SOC CHEMISTRY  

Synthesis of 3-norcephalosporin 1 was performed successfully by reaction of either 3-trifluoromethylsulfonyloxy-Delta(3)-cephem 2, allenecarboxylate 3 or 3,4-disubstitued but-2-enoates 4 with copper(I) chloride and tributyltin hydride in N-methylpyrrolidin-2-one (NMP). Generation and reactions of a copper(I) hydride species in the copper(I) chloride-tributyltin hydride-NMP or N,N-dimethylformamide (DMF) system are discussed.

Web of Science

researchmap

Language：English   Publisher：Georg Thieme Verlag  

Electrochemical alkenylation of aldehydes using an Al sacrificial anode in the presence of Cr(II)/Ni(II) catalysts afforded the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1055/s-1999-2555

Scopus

researchmap

Language：English   Publisher：Georg Thieme Verlag  

Electrochemical alkenylation of aldehydes using an Al sacrificial anode in the presence of Cr(II)/Ni(II) catalysts afforded the corresponding allyl alcohol derivatives in good to moderate yields.

DOI： 10.1055/s-1999-2555

Scopus

researchmap

Language：English   Publisher：ROYAL SOC CHEMISTRY  

Synthesis of 3-norcephalosporin 1 was performed successfully by reaction of either 3-trifluoromethylsulfonyloxy-Delta(3)-cephem 2, allenecarboxylate 3 or 3,4-disubstitued but-2-enoates 4 with copper(I) chloride and tributyltin hydride in N-methylpyrrolidin-2-one (NMP). Generation and reactions of a copper(I) hydride species in the copper(I) chloride-tributyltin hydride-NMP or N,N-dimethylformamide (DMF) system are discussed.

Web of Science

researchmap

Language：English   Publisher：Georg Thieme Verlag  

A new combination of organic reductant, tetrakis(dimethylamino)ethylene, and transition metal catalysts is reported for allylation of aldehydes and ketones.

DOI： 10.1055/s-1999-2995

Scopus

researchmap

Language：English   Publishing type：Book review, literature introduction, etc.   Publisher：CHEMICAL SOC JAPAN  

The treatment of tribromofluoromethane with BuLi in THF-Et2O (2: 1) at -130 degrees C generated dibromofluoromethyllithium, which was allowed to react smoothly with a coexisting aldehyde or ketone (RR'C=O) to give fluorinated alcohol RR'C(OH)CFBr2 (3) in good yield. Alcohol 3 was converted stereoselectively to (E)-1-bromo- 1,2-difluoro olefin 5 via fluorination with Et2NSF3, followed by dehydrobromination with lithium 2,2,6,6-tetramethylpiperidide, while (E)-1-bromo-1-fluoro olefin was obtained with high selectivity by acetylation of 3, followed by reductive elimination using EtMgBr/(i-Pr)(2)NH. Difluoro olefin 5 underwent a cross-coupling reaction with an aryl, alkenyl, or alkynylmetal reagent to afford the corresponding fluoro olefin with retention of configuration. On the other hand, the treatment of RCH[OCH2O(CH2)(2)OCH3]CFBr2 with BuLi at -130 degrees C in the presence of 4-heptanone gave the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of chelation between lithium and oxygen atoms of the (2-methoxyethoxy)methyl group. Starting with 2-phenylpropanal, a product is obtained highly selectively containing three contiguous stereocenters including a -CFBr- moiety.

DOI： 10.1246/bcsj.71.2903

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5, 5-dimethylhydantoin, various organic sulfides underwent a Pummerer-type rearrangement, followed by fluorination, to give alpha-fluoro sulfides. The fluoro-Pummerer rearrangement, when applied to RCH(SMe)CF2SMe, gave trifluoro sulfides RCF(SMe)CF2SMe. When an HF-pyridine reagent was used as the fluorinating agent, an oxidative desulfurization-fluorination reaction occurred depending on the structure of the substrates.

DOI： 10.1246/bcsj.71.2687

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

Trifluoromethylamines are easily synthesized from dithiocarbamates by a reagent system consisting of tetrabutylammonium dihydrogentrifluoride and an N-halo imide under mild conditions. When this reaction was applied to dithiocarbamates ArN(R)CS2Me at higher temperatures, the trifluoromethylation was accompanied by halogen substitution at the p-position of the Ar group. The synthesis of trifluoromethyl-substituted adenosine is also described.

DOI： 10.1246/bcsj.71.1973

Web of Science

researchmap

Language：English   Publisher：GEORG THIEME VERLAG  

5-Substituted 4,4-dialkoxy-2-cyclohexen-1-ones were electrosynthesized from 4,4-disubstituted 2,5-cyclohexadien-1-ones, which were obtained from 1,4-dialkoxybenzene derivatives by electrolysis, by electro-generated base (EG-base)-promoted Michael addition with CH2E2 (E = CO2R, COMe) in moderate to almost quantitative yield. The cyclohexenone derivatives were found to be a good precursor of benzofuranone derivatives through acid-promoted intramolecular lactonization.

Web of Science

researchmap

Language：English   Publisher：Chemical Society of Japan  

The treatment of tribromofluoromethane with BuLi in THF-Et2O (2: 1) at - 130°C generated dibromofluoromethyllithium, which was allowed to react smoothly with a coexisting aldehyde or ketone (RR'C=O) to give fluorinated alcohol RR'C(OH)CFBr2 (3) in good yield. Alcohol 3 was converted stereoselectively to (E)-1-bromo-1,2-difluoro olefin 5 via fluorination with Et2NSF3, followed by dehydrobromination with lithium 2,2,6,6- tetramethylpiperidide, while (E)-1-bromo-1-fluoro olefin was obtained with high selectivity by acetylation of 3, followed by reductive elimination using EtMgBr/(i-Pr)2NH. Difluoro olefin 5 underwent a cross-coupling reaction with an aryl, alkenyl, or alkynylmetal reagent to afford the corresponding fluoro olefin with retention of configuration. On the other hand, the treatment of RCH[OCH2O(CH2)2OCH3]CFBr2 with BuLi at -130°C in the presence of 4- heptanone gave the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of chelation between lithium and oxygen atoms of the (2-methoxyethoxy)methyl group. Starting with 2- phenylpropanal, a product is obtained highly selectively containing three contiguous stereocenters including a -CFBr-moiety.

DOI： 10.1246/bcsj.71.2903

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

The treatment of tribromofluoromethane with BuLi in THF-Et2O (2: 1) at - 130°C generated dibromofluoromethyllithium, which was allowed to react smoothly with a coexisting aldehyde or ketone (RR'C=O) to give fluorinated alcohol RR'C(OH)CFBr2 (3) in good yield. Alcohol 3 was converted stereoselectively to (E)-1-bromo-1,2-difluoro olefin 5 via fluorination with Et2NSF3, followed by dehydrobromination with lithium 2,2,6,6- tetramethylpiperidide, while (E)-1-bromo-1-fluoro olefin was obtained with high selectivity by acetylation of 3, followed by reductive elimination using EtMgBr/(i-Pr)2NH. Difluoro olefin 5 underwent a cross-coupling reaction with an aryl, alkenyl, or alkynylmetal reagent to afford the corresponding fluoro olefin with retention of configuration. On the other hand, the treatment of RCH[OCH2O(CH2)2OCH3]CFBr2 with BuLi at -130°C in the presence of 4- heptanone gave the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of chelation between lithium and oxygen atoms of the (2-methoxyethoxy)methyl group. Starting with 2- phenylpropanal, a product is obtained highly selectively containing three contiguous stereocenters including a -CFBr-moiety.

DOI： 10.1246/bcsj.71.2903

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

The treatment of tribromofluoromethane with BuLi in THF-Et2O (2: 1) at - 130°C generated dibromofluoromethyllithium, which was allowed to react smoothly with a coexisting aldehyde or ketone (RR'C=O) to give fluorinated alcohol RR'C(OH)CFBr2 (3) in good yield. Alcohol 3 was converted stereoselectively to (E)-1-bromo-1,2-difluoro olefin 5 via fluorination with Et2NSF3, followed by dehydrobromination with lithium 2,2,6,6- tetramethylpiperidide, while (E)-1-bromo-1-fluoro olefin was obtained with high selectivity by acetylation of 3, followed by reductive elimination using EtMgBr/(i-Pr)2NH. Difluoro olefin 5 underwent a cross-coupling reaction with an aryl, alkenyl, or alkynylmetal reagent to afford the corresponding fluoro olefin with retention of configuration. On the other hand, the treatment of RCH[OCH2O(CH2)2OCH3]CFBr2 with BuLi at -130°C in the presence of 4- heptanone gave the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of chelation between lithium and oxygen atoms of the (2-methoxyethoxy)methyl group. Starting with 2- phenylpropanal, a product is obtained highly selectively containing three contiguous stereocenters including a -CFBr-moiety.

DOI： 10.1246/bcsj.71.2903

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5- dimethylhydantoin, various organic sulfides underwent a Pummerer-type rearrangement, followed by fluorination, to give α-fluoro sulfides. The fluoro-Pummerer rearrangement, when applied to RCH(SMe)CF2SMe, gave trifluoro sulfides RCF(SMe)CF2SMe. When an HF-pyridine reagent was used as the fluorinating agent, an oxidative desulfurization-fluorination reaction occurred depending on the structure of the substrates.

DOI： 10.1246/bcsj.71.2687

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5- dimethylhydantoin, various organic sulfides underwent a Pummerer-type rearrangement, followed by fluorination, to give α-fluoro sulfides. The fluoro-Pummerer rearrangement, when applied to RCH(SMe)CF2SMe, gave trifluoro sulfides RCF(SMe)CF2SMe. When an HF-pyridine reagent was used as the fluorinating agent, an oxidative desulfurization-fluorination reaction occurred depending on the structure of the substrates.

DOI： 10.1246/bcsj.71.2687

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5- dimethylhydantoin, various organic sulfides underwent a Pummerer-type rearrangement, followed by fluorination, to give α-fluoro sulfides. The fluoro-Pummerer rearrangement, when applied to RCH(SMe)CF2SMe, gave trifluoro sulfides RCF(SMe)CF2SMe. When an HF-pyridine reagent was used as the fluorinating agent, an oxidative desulfurization-fluorination reaction occurred depending on the structure of the substrates.

DOI： 10.1246/bcsj.71.2687

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

The oxidative desulfurization-fluorination of orthothioesters of type RCH2C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave bromodifluorination products RCHBrCF2SMe in good yields. The products were converted into bromodifluoro olefins RCBr=CF2 via oxidation and thermolysis. In a similar way, the orthothioesters of type RCH(OH)C(SMe)3 or RCH(OAc)C(SMe)3 were fluorinated to afford difluoro ketones RCOCF2SMe or difluoro acetates RCH(OAc)CF2SMe, respectively. The difiuoro acetates were reduced to RCH(OAc)CF2H by radical reduction. The mechanisms are discussed for difluorination accompanied by bromination or oxidation.

DOI： 10.1246/bcsj.71.1939

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

The oxidative desulfurization-fluorination of orthothioesters of type RCH2C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave bromodifluorination products RCHBrCF2SMe in good yields. The products were converted into bromodifluoro olefins RCBr=CF2 via oxidation and thermolysis. In a similar way, the orthothioesters of type RCH(OH)C(SMe)3 or RCH(OAc)C(SMe)3 were fluorinated to afford difluoro ketones RCOCF2SMe or difluoro acetates RCH(OAc)CF2SMe, respectively. The difiuoro acetates were reduced to RCH(OAc)CF2H by radical reduction. The mechanisms are discussed for difluorination accompanied by bromination or oxidation.

DOI： 10.1246/bcsj.71.1939

Scopus

researchmap

Language：English   Publisher：Chemical Society of Japan  

The oxidative desulfurization-fluorination of orthothioesters of type RCH2C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave bromodifluorination products RCHBrCF2SMe in good yields. The products were converted into bromodifluoro olefins RCBr=CF2 via oxidation and thermolysis. In a similar way, the orthothioesters of type RCH(OH)C(SMe)3 or RCH(OAc)C(SMe)3 were fluorinated to afford difluoro ketones RCOCF2SMe or difluoro acetates RCH(OAc)CF2SMe, respectively. The difiuoro acetates were reduced to RCH(OAc)CF2H by radical reduction. The mechanisms are discussed for difluorination accompanied by bromination or oxidation.

DOI： 10.1246/bcsj.71.1939

Scopus

researchmap

Language：English   Publisher：Georg Thieme Verlag  

5-Substituted 4,4-dialkoxy-2-cyclohexen-1-ones were electro-synthesized from 4,4-disubstituted 2,5-cyclohexadien-1-ones, which were obtained from 1,4-dialkoxybenzene derivatives by electrolysis, by electro-generated base (EG-base)-promoted Michael addition with CH2E2 (E = CO2R, COMe) in moderate to almost quantitative yield. The cyclohexenone derivatives were found to be a good precursor of benzofuranone derivatives through acid-promoted intramolecular lactonization.

DOI： 10.1055/s-1998-1752

Scopus

researchmap

Language：English  

Terminal-biradical compounds 1 having two N-oxyl groups connected with conjugated π-systems were synthesized by (1) addition of magnesium acetylide to 4-oxo-TEMPO, followed by dehydration, or (2) cross-coupling between acetylene and vinyl triflate derived from 4-oxo-TEMPO.

DOI： 10.1016/S0040-4039(97)01732-2

Scopus

researchmap

Language：English  

Terminal-biradical compounds 1 having two N-oxyl groups connected with conjugated π-systems were synthesized by (1) addition of magnesium acetylide to 4-oxo-TEMPO, followed by dehydration, or (2) cross-coupling between acetylene and vinyl triflate derived from 4-oxo-TEMPO.

DOI： 10.1016/S0040-4039(97)01732-2

Scopus

researchmap

Language：English  

Terminal-biradical compounds 1 having two N-oxyl groups connected with conjugated π-systems were synthesized by (1) addition of magnesium acetylide to 4-oxo-TEMPO, followed by dehydration, or (2) cross-coupling between acetylene and vinyl triflate derived from 4-oxo-TEMPO.

DOI： 10.1016/S0040-4039(97)01732-2

Scopus

researchmap

Language：English   Publisher：Royal Society of Chemistry  

The reagent consisting of 70% HF-py (py = pyridine) and a halonium oxidant converts R-OCS2Me into either R-OCF3 (R = primary) or R-F (R = secondary, tertiary or benzylic) whereas the 50% HF-py system converts R-OCS2Me (R = secondary) into R-OCF3.

DOI： 10.1039/a607897d

Scopus

researchmap

Language：English   Publisher：Royal Society of Chemistry  

The reagent consisting of 70% HF-py (py = pyridine) and a halonium oxidant converts R-OCS2Me into either R-OCF3 (R = primary) or R-F (R = secondary, tertiary or benzylic) whereas the 50% HF-py system converts R-OCS2Me (R = secondary) into R-OCF3.

DOI： 10.1039/a607897d

Scopus

researchmap

Language：English   Publisher：Elsevier Ltd  

Treatment of RCH(OMEM)CFBr2 with n-BuLi at -130°C in the presence of 4-heptanone gives the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of the chelation between lithium and oxygen atoms of the MEM group. Starting with 2-phenylpropanal, a product is produced highly selectively containing three contiguous stereocenters including a -CFBr- moiety.

DOI： 10.1016/0040-4039(96)01684-X

Scopus

researchmap

Language：English   Publisher：Elsevier Ltd  

Treatment of RCH(OMEM)CFBr2 with n-BuLi at -130°C in the presence of 4-heptanone gives the corresponding adduct diastereoselectively. The stereochemical outcome is explained in terms of the chelation between lithium and oxygen atoms of the MEM group. Starting with 2-phenylpropanal, a product is produced highly selectively containing three contiguous stereocenters including a -CFBr- moiety.

DOI： 10.1016/0040-4039(96)01684-X

Scopus

researchmap

J-GLOBAL

researchmap

Language：Japanese   Publisher：Japanese Liquid Crystal Society  

Dithiocarbamates of type Ar-N(R)CS_2R' or xanthates of type Ar-OCS_2R were converted into Ar-N(R)CF_3 or Ar-OCF_3, respectively, by oxidative desulfurization-fluorination. Electro-optical properties of liquid crystals containing-N(R)CF_3 or -OCF_3 group will be discussed. They are shown to be stable components of nematic liquid crystals mixture.

CiNii Article

CiNii Books

researchmap

Language：English  

A palladium complex with an optically active ligand catalyzes asymmetric hydrosilylation of 1,3-dienes using difluoro(phenyl)silane to give optically active allyl difluoro(phenyl)silanes in good enantiomeric excess. © 1995.

DOI： 10.1016/0022-328X(95)00311-D

Scopus

researchmap

Language：English  

A palladium complex with an optically active ligand catalyzes asymmetric hydrosilylation of 1,3-dienes using difluoro(phenyl)silane to give optically active allyl difluoro(phenyl)silanes in good enantiomeric excess. © 1995.

DOI： 10.1016/0022-328X(95)00311-D

Scopus

researchmap

Language：English  

A palladium complex with an optically active ligand catalyzes asymmetric hydrosilylation of 1,3-dienes using difluoro(phenyl)silane to give optically active allyl difluoro(phenyl)silanes in good enantiomeric excess. © 1995.

DOI： 10.1016/0022-328X(95)00311-D

Scopus

researchmap

Language：English  

A palladium complex with an optically active ligand catalyzes asymmetric hydrosilylation of 1,3-dienes using difluoro(phenyl)silane to give optically active allyl difluoro(phenyl)silanes in good enantiomeric excess. © 1995.

DOI： 10.1016/0022-328X(95)00311-D

Scopus

researchmap

Language：English  

A palladium complex with an optically active ligand catalyzes asymmetric hydrosilylation of 1,3-dienes using difluoro(phenyl)silane to give optically active allyl difluoro(phenyl)silanes in good enantiomeric excess. © 1995.

DOI： 10.1016/0022-328X(95)00311-D

Scopus

researchmap

Language：English  

(E)-vic-Difluoro olefin, RCFCFBr, was synthesized by dehydrobromination of RCFHCFBr2 using lithium 2,2,6,6-tetramethylpiperidide. (E)-Fluoro olefin, RCHCFBr, was obtained by treatment of RCH(OAc)CFBr2 with EtMgBr and HN(i-Pr)2. © 1995.

DOI： 10.1016/0040-4039(95)01257-I

Scopus

researchmap

Language：English  

(E)-vic-Difluoro olefin, RCFCFBr, was synthesized by dehydrobromination of RCFHCFBr2 using lithium 2,2,6,6-tetramethylpiperidide. (E)-Fluoro olefin, RCHCFBr, was obtained by treatment of RCH(OAc)CFBr2 with EtMgBr and HN(i-Pr)2. © 1995.

DOI： 10.1016/0040-4039(95)01257-I

Scopus

researchmap

Language：English  

(E)-vic-Difluoro olefin, RCFCFBr, was synthesized by dehydrobromination of RCFHCFBr2 using lithium 2,2,6,6-tetramethylpiperidide. (E)-Fluoro olefin, RCHCFBr, was obtained by treatment of RCH(OAc)CFBr2 with EtMgBr and HN(i-Pr)2. © 1995.

DOI： 10.1016/0040-4039(95)01257-I

Scopus

researchmap

Language：English  

(E)-vic-Difluoro olefin, RCFCFBr, was synthesized by dehydrobromination of RCFHCFBr2 using lithium 2,2,6,6-tetramethylpiperidide. (E)-Fluoro olefin, RCHCFBr, was obtained by treatment of RCH(OAc)CFBr2 with EtMgBr and HN(i-Pr)2. © 1995.

DOI： 10.1016/0040-4039(95)01257-I

Scopus

researchmap

Language：English  

Oxidative desulfurization-fluorination of RCH(OH)C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave RC(O)CF2SMe, whereas treatment of the same substrates with Et2NSF3 afforded RCH(SMe)CF2SMe. © 1995.

DOI： 10.1016/0040-4039(95)01234-9

Scopus

researchmap

Language：English  

Oxidative desulfurization-fluorination of RCH(OH)C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave RC(O)CF2SMe, whereas treatment of the same substrates with Et2NSF3 afforded RCH(SMe)CF2SMe. © 1995.

DOI： 10.1016/0040-4039(95)01234-9

Scopus

researchmap

Language：English  

Oxidative desulfurization-fluorination of RCH(OH)C(SMe)3 using n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin gave RC(O)CF2SMe, whereas treatment of the same substrates with Et2NSF3 afforded RCH(SMe)CF2SMe. © 1995.

DOI： 10.1016/0040-4039(95)01234-9

Scopus

researchmap

Language：English  

Alkenylfluorosilanes smoothly underwent cross-coupling reaction with allylic carbonates in the presence of a palladium catalyst andin the absence of fluoride ion to give 1, 4-dienes in good yields with retention of configuration. © 1995 Elsevier Science Ltd.

DOI： 10.1016/0040-4039(95)00082-N

Scopus

researchmap

Language：English  

Alkenylfluorosilanes smoothly underwent cross-coupling reaction with allylic carbonates in the presence of a palladium catalyst andin the absence of fluoride ion to give 1, 4-dienes in good yields with retention of configuration. © 1995 Elsevier Science Ltd.

DOI： 10.1016/0040-4039(95)00082-N

Scopus

researchmap

Language：English  

Alkenylfluorosilanes smoothly underwent cross-coupling reaction with allylic carbonates in the presence of a palladium catalyst andin the absence of fluoride ion to give 1, 4-dienes in good yields with retention of configuration. © 1995 Elsevier Science Ltd.

DOI： 10.1016/0040-4039(95)00082-N

Scopus

researchmap

Language：English  

Alkenylfluorosilanes smoothly underwent cross-coupling reaction with allylic carbonates in the presence of a palladium catalyst andin the absence of fluoride ion to give 1, 4-dienes in good yields with retention of configuration. © 1995 Elsevier Science Ltd.

DOI： 10.1016/0040-4039(95)00082-N

Scopus

researchmap

Language：English  

Oxidative desulfurization-fluorination of methyl N-pyridyl(or N-pyrimidyl)-N-alkyldithiocarbamates gave the corresponding trifluoromethylamino-substituted pyridines (or pyrimidines), which underwent cross-coupling reaction to give a new type of liquid crystalline compounds having trifluoromethylamino group. © 1995.

DOI： 10.1016/0040-4039(94)02253-8

Scopus

researchmap

Language：English  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin, various organic sulfides were readily fluorinated to give α-fluoro sulfides. When (HF)9-Py was used as the fluorinating agent, normal oxidative desulfurization fluorination occurred depending on the structure of the substrates.

DOI： 10.1016/0040-4039(95)01768-D

Scopus

researchmap

Language：English  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin, various organic sulfides were readily fluorinated to give α-fluoro sulfides. When (HF)9-Py was used as the fluorinating agent, normal oxidative desulfurization fluorination occurred depending on the structure of the substrates.

DOI： 10.1016/0040-4039(95)01768-D

Scopus

researchmap

Language：English  

Upon treatment with n-Bu4NH2F3 and 1,3-dibromo-5,5-dimethylhydantoin, various organic sulfides were readily fluorinated to give α-fluoro sulfides. When (HF)9-Py was used as the fluorinating agent, normal oxidative desulfurization fluorination occurred depending on the structure of the substrates.

DOI： 10.1016/0040-4039(95)01768-D

Scopus

researchmap

Language：English   Publisher：The Chemical Society of Japan  

Iodofluorination of alkenes was achieved with N-iodosuccinimide, potassium hydrogendifluoride, and 1 M hydrofluoric acid using tetrabutylammonium fluoride as a phase-transfer catalyst. The active fluorinating reagent was shown to be tetrabutylammonium dihydrogentrifluoride by preparing the salt in a different way and by effecting the same transformation under anhydrous conditions. Bromofluorination of alkenes also was carried out using 1,3-dibromo-5,5-dimethylhydantoin. Treatment of the I–F adducts with DBU afforded fluoro olefins stereospecifically.

DOI： 10.1246/bcsj.68.1799

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

Iodofluorination of alkenes was achieved with N-iodosuccinimide, potassium hydrogendifluoride, and 1 M hydrofluoric acid using tetrabutylammonium fluoride as a phase-transfer catalyst. The active fluorinating reagent was shown to be tetrabutylammonium dihydrogentrifluoride by preparing the salt in a different way and by effecting the same transformation under anhydrous conditions. Bromofluorination of alkenes also was carried out using 1,3-dibromo-5,5-dimethylhydantoin. Treatment of the I–F adducts with DBU afforded fluoro olefins stereospecifically.

DOI： 10.1246/bcsj.68.1799

CiNii Article

researchmap

J-GLOBAL

researchmap

Language：English  

A variety of alkyltrifluorosilanes were found to couple with aryl halides in the presence of Pd(PPh3)4 catalyst and tetrabutylammonium fluoride (TBAF) to give the corresponding cross-coupled products in moderate to good yields. © 1994.

DOI： 10.1016/S0040-4039(00)78258-X

Scopus

researchmap

Language：English  

A variety of alkyltrifluorosilanes were found to couple with aryl halides in the presence of Pd(PPh3)4 catalyst and tetrabutylammonium fluoride (TBAF) to give the corresponding cross-coupled products in moderate to good yields. © 1994.

DOI： 10.1016/S0040-4039(00)78258-X

Scopus

researchmap

Language：English  

A variety of alkyltrifluorosilanes were found to couple with aryl halides in the presence of Pd(PPh3)4 catalyst and tetrabutylammonium fluoride (TBAF) to give the corresponding cross-coupled products in moderate to good yields. © 1994.

DOI： 10.1016/S0040-4039(00)78258-X

Scopus

researchmap

Language：English  

The syn and anti isomers of 2-fluoro-2-(trifluoromethyl)-3-hydroxy ketones are reduced in a highly 1,2-syn diastereoselective manner with lithium aluminum hydride or diisobutylaluminum hydride in tetrahydrofuran at -78 °C, affording 1,2-syn-2,3-syn- and 1,2-syn-2,3-anti-2-fluoro-2-(trifluoromethyl)-1,3-diols, respectively, in excellent yields. High 1,2-syn stereoselectivity in the reduction can be ascribed to the presence of the 2-trifluoromethyl substituent. © 1994.

DOI： 10.1016/S0040-4039(00)77080-8

Scopus

researchmap

Language：English  

The syn and anti isomers of 2-fluoro-2-(trifluoromethyl)-3-hydroxy ketones are reduced in a highly 1,2-syn diastereoselective manner with lithium aluminum hydride or diisobutylaluminum hydride in tetrahydrofuran at -78 °C, affording 1,2-syn-2,3-syn- and 1,2-syn-2,3-anti-2-fluoro-2-(trifluoromethyl)-1,3-diols, respectively, in excellent yields. High 1,2-syn stereoselectivity in the reduction can be ascribed to the presence of the 2-trifluoromethyl substituent. © 1994.

DOI： 10.1016/S0040-4039(00)77080-8

Scopus

researchmap

Language：English  

The syn and anti isomers of 2-fluoro-2-(trifluoromethyl)-3-hydroxy ketones are reduced in a highly 1,2-syn diastereoselective manner with lithium aluminum hydride or diisobutylaluminum hydride in tetrahydrofuran at -78 °C, affording 1,2-syn-2,3-syn- and 1,2-syn-2,3-anti-2-fluoro-2-(trifluoromethyl)-1,3-diols, respectively, in excellent yields. High 1,2-syn stereoselectivity in the reduction can be ascribed to the presence of the 2-trifluoromethyl substituent. © 1994.

DOI： 10.1016/S0040-4039(00)77080-8

Scopus

researchmap

Language：English  

N-Perfluoroalkylamines were synthesized from perfluoroalkanethioamides, which were easily accessible from perfluoroalkanamides, by the action of N-halo imide and nBu4NH2F3. © 1994.

DOI： 10.1016/S0040-4039(00)76719-0

Scopus

researchmap

Language：English  

N-Perfluoroalkylamines were synthesized from perfluoroalkanethioamides, which were easily accessible from perfluoroalkanamides, by the action of N-halo imide and nBu4NH2F3. © 1994.

DOI： 10.1016/S0040-4039(00)76719-0

Scopus

researchmap

Language：English  

Perfluoroalkyl-substituted arenes have been readily synthesized from 2-aryl-2-perfluoroalkyl-1,3-dithiolanes by the action of an N-halo imide and HF/pyridine (or HF/melamine). © 1994.

DOI： 10.1016/0022-1139(94)03139-8

Scopus

researchmap

Language：English  

Methods for preparation of organofluorine compounds are reviewed from the view point of the reagent system consisting of fluoride ion and an oxidant. Reagents like N-halo imides are often used as the oxidant, which may be replaced by electrochemical oxidation. These methods provide us with various types of fluorinated compounds efficiently and selectively under mild conditions. © 1993, The Society of Synthetic Organic Chemistry, Japan. All rights reserved.

DOI： 10.5059/yukigoseikyokaishi.51.1124

Scopus

researchmap

Language：English  

Treatment of xanthates R-OC(S)SMe with (HF)9/Py and 1,3-dibromo-5,5-dimethylhydantoin gives trifluoromethyl ethers R-OCF3 through intermediates R-OCF2SMe, which could be isolated upon treatment of xanthates with n-Bu4N+H2F3- and N-bromosuccinimide. © 1992.

DOI： 10.1016/S0040-4039(00)74681-8

Scopus

researchmap

Language：English  

Treatment of xanthates R-OC(S)SMe with (HF)9/Py and 1,3-dibromo-5,5-dimethylhydantoin gives trifluoromethyl ethers R-OCF3 through intermediates R-OCF2SMe, which could be isolated upon treatment of xanthates with n-Bu4N+H2F3- and N-bromosuccinimide. © 1992.

DOI： 10.1016/S0040-4039(00)74681-8

Scopus

researchmap

Language：English  

Reaction of methyl dithiocarbamates R1R2N-C(S)SMe with n-Bu4N+H2F3- and N-bromosuccinimide provides trifluoromethylamines R1R2N-CF3 in good yields. © 1992.

DOI： 10.1016/S0040-4039(00)74682-X

Scopus

researchmap

Language：English  

Reaction of methyl dithiocarbamates R1R2N-C(S)SMe with n-Bu4N+H2F3- and N-bromosuccinimide provides trifluoromethylamines R1R2N-CF3 in good yields. © 1992.

DOI： 10.1016/S0040-4039(00)74682-X

Scopus

researchmap

Language：English  

Treatment of xanthates R-OC(S)SMe with (HF)9/Py and 1,3-dibromo-5,5-dimethylhydantoin gives trifluoromethyl ethers R-OCF3 through intermediates R-OCF2SMe, which could be isolated upon treatment of xanthates with n-Bu4N+H2F3- and N-bromosuccinimide. © 1992.

DOI： 10.1016/S0040-4039(00)74681-8

Scopus

researchmap

Language：English  

Regio-, stereo-, and chemoselective halofluorination of alkenes is achieved using N-haloamides and tetrabutylammonium dihydrogentrifluoride, and the resulting F-I adducts were successfully converted into fluoroalkenes under dehydroiodination with 1,8-diazabicyclo[5.4.0]undec-7-ene. © 1991.

DOI： 10.1016/S0040-4039(00)92048-3

Scopus

researchmap

Language：English  

Regio-, stereo-, and chemoselective halofluorination of alkenes is achieved using N-haloamides and tetrabutylammonium dihydrogentrifluoride, and the resulting F-I adducts were successfully converted into fluoroalkenes under dehydroiodination with 1,8-diazabicyclo[5.4.0]undec-7-ene. © 1991.

DOI： 10.1016/S0040-4039(00)92048-3

Scopus

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

2-[(Trimethylsilyl]methyl]-3-chloro-3,3-difluoropropene, readily prepared in two steps from methyl chlorodifluoroacetate and (trimethylsilyl)methylmagnesium chloride, is reduced to couple regioselectively with a variety of carbonly compounds in the presence of zinc-copper(l) chloride or -silver acetate to give 2,2-difluoro-3-[(trimethylsilyl)methyl]-3-buten-1-ol derivatives in good to excellent yields.

DOI： 10.1016/S0040-4039(00)74490-X

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

2-[(Trimethylsilyl]methyl]-3-chloro-3,3-difluoropropene, readily prepared in two steps from methyl chlorodifluoroacetate and (trimethylsilyl)methylmagnesium chloride, is reduced to couple regioselectively with a variety of carbonly compounds in the presence of zinc-copper(l) chloride or -silver acetate to give 2,2-difluoro-3-[(trimethylsilyl)methyl]-3-buten-1-ol derivatives in good to excellent yields.

DOI： 10.1016/S0040-4039(00)74490-X

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

2-[(Trimethylsilyl]methyl]-3-chloro-3,3-difluoropropene, readily prepared in two steps from methyl chlorodifluoroacetate and (trimethylsilyl)methylmagnesium chloride, is reduced to couple regioselectively with a variety of carbonly compounds in the presence of zinc-copper(l) chloride or -silver acetate to give 2,2-difluoro-3-[(trimethylsilyl)methyl]-3-buten-1-ol derivatives in good to excellent yields.

DOI： 10.1016/S0040-4039(00)74490-X

Web of Science

researchmap

Language：English  

Diethyl 1-substituted-1-perfluoroalkenyl phosphates (1), available from perfluoroalkyl ketones and sodium diethyl phosphite, were allowed to react with a reagent derived from lithium aluminum hydride and a metal salt or brominein tetrahydrofuran below -30 °C and successively treated with water or aldehydes to give rise to the corresponding 1H-perfluoroalkyl ketones (4) or a-fluoro-a-perfluoroalkyl-β-hydroxy ketones (5), respectively, in moderate to good yields. Copper(II) bromide, copper(I) bromide, and zinc chloride could be employed as the metal salt in the reaction. The phosphates also underwent reductive dephosphorylation with diisobutylaluminum hydride to generate the aluminum enolates of 1H-perfluoroalkyl ketones. 19F NMR analyses indicated that their structure is not an α-metallo ketone but an oxygen-metalated species and that they are appreciably stable below 0 °C. Treatment with a wide variety of aldehydes at 0 °C yielded the corresponding aldol products 5 in good to excellent yields, whereas ketones did not react. © 1990, American Chemical Society. All rights reserved.

DOI： 10.1021/jo00297a028

Scopus

researchmap

Language：English  

Diethyl 1-substituted-1-perfluoroalkenyl phosphates (1), available from perfluoroalkyl ketones and sodium diethyl phosphite, were allowed to react with a reagent derived from lithium aluminum hydride and a metal salt or brominein tetrahydrofuran below -30 °C and successively treated with water or aldehydes to give rise to the corresponding 1H-perfluoroalkyl ketones (4) or a-fluoro-a-perfluoroalkyl-β-hydroxy ketones (5), respectively, in moderate to good yields. Copper(II) bromide, copper(I) bromide, and zinc chloride could be employed as the metal salt in the reaction. The phosphates also underwent reductive dephosphorylation with diisobutylaluminum hydride to generate the aluminum enolates of 1H-perfluoroalkyl ketones. 19F NMR analyses indicated that their structure is not an α-metallo ketone but an oxygen-metalated species and that they are appreciably stable below 0 °C. Treatment with a wide variety of aldehydes at 0 °C yielded the corresponding aldol products 5 in good to excellent yields, whereas ketones did not react. © 1990, American Chemical Society. All rights reserved.

DOI： 10.1021/jo00297a028

Scopus

researchmap

Language：English  

Diethyl 1-substituted-1-perfluoroalkenyl phosphates (1), available from perfluoroalkyl ketones and sodium diethyl phosphite, were allowed to react with a reagent derived from lithium aluminum hydride and a metal salt or brominein tetrahydrofuran below -30 °C and successively treated with water or aldehydes to give rise to the corresponding 1H-perfluoroalkyl ketones (4) or a-fluoro-a-perfluoroalkyl-β-hydroxy ketones (5), respectively, in moderate to good yields. Copper(II) bromide, copper(I) bromide, and zinc chloride could be employed as the metal salt in the reaction. The phosphates also underwent reductive dephosphorylation with diisobutylaluminum hydride to generate the aluminum enolates of 1H-perfluoroalkyl ketones. 19F NMR analyses indicated that their structure is not an α-metallo ketone but an oxygen-metalated species and that they are appreciably stable below 0 °C. Treatment with a wide variety of aldehydes at 0 °C yielded the corresponding aldol products 5 in good to excellent yields, whereas ketones did not react. © 1990, American Chemical Society. All rights reserved.

DOI： 10.1021/jo00297a028

Scopus

researchmap

Language：English  

Chlorodifluoromethyl ketones CF2ClCOR, where R is an alkyl, aryl, and l-alkynyl group, underwent the Reformatsky-type aldol reaction with a wide variety of aldehydes or ketones in the presence of acid-washed zinc dust and copper(I) chloride or silver acetate to give the corresponding α,α-difluoro-β-hydroxy ketones in good to excellent yields. Specific activation of zinc metal with the metal salt is essential to achieve high efficiency of the reaction, depending upon the structures of the chlorodifluoromethyl ketones and the carbonyl compounds employed. In-situ formed intermediates in these reactions were successfully detected by 19F NMR spectroscopy, which suggests that their structure is not an α-metallo ketone but an oxygen-metallated species possessing the zinc(II) metal as counter cation.

DOI： 10.1246/bcsj.63.428

Scopus

researchmap

Language：English  

DOI： 10.1246/bcsj.63.1191

Scopus

researchmap

Language：English   Publisher：The Chemical Society of Japan  

1-Substituted F-1-alkenyl phosphates, prepared easily from F-alkyl ketones, were treated with diisobutylaluminium hydride in tetrahydrofuran at 0 °C for 5 min or at room temperature for 30 min to generate quantitatively the corresponding ketone aluminium(III) enolates, which underwent the aldol reaction with various aldehydes at 0 °C to give α-fluoro-α-F-alkyl β-hydroxy ketones in good to excellent yields.

DOI： 10.1246/cl.1989.1191

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

1-Substituted F-1-alkenyl phosphates, prepared easily from F-alkyl ketones, were treated with diisobutylaluminium hydride in tetrahydrofuran at 0 °C for 5 min or at room temperature for 30 min to generate quantitatively the corresponding ketone aluminium(III) enolates, which underwent the aldol reaction with various aldehydes at 0 °C to give α-fluoro-α-F-alkyl β-hydroxy ketones in good to excellent yields.

DOI： 10.1246/cl.1989.1191

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

1-Substituted F-1-alkenyl phosphates, prepared easily from F-alkyl ketones, were treated with diisobutylaluminium hydride in tetrahydrofuran at 0 °C for 5 min or at room temperature for 30 min to generate quantitatively the corresponding ketone aluminium(III) enolates, which underwent the aldol reaction with various aldehydes at 0 °C to give α-fluoro-α-F-alkyl β-hydroxy ketones in good to excellent yields.

DOI： 10.1246/cl.1989.1191

CiNii Article

researchmap

Language：English   Publisher：MARCEL DEKKER INC  

Web of Science

researchmap

Language：English  

F-alkyl iodides readily reacted with a variety of alkenes in methanol at room temperature under the influence of metallic tin(0)-silver(I) acetate of metallic tin(0)-copper(I) chloride to afford the corresponding addition products, F- alkylated iodides, in good to excellent yields. This addition reaction was also promoted by the use of a metallic tin(0)- aluminium(0) reagent, though gentle heating was necessary for allowing the reaction to proceed. © 1988.

DOI： 10.1016/S0022-1139(00)82786-4

Scopus

researchmap

Language：English  

1-Substituted F-1-alkenyl phosphates, easily prepared from F-alkyl ketones and the sodium salt of diethyl phosphite, were allowed to react with various phosphonium ylides in tetrahydrofuran or hexane at room temperature or at the reflux temperature of the solvent to lead to the corresponding polyfluorinated 1,3-diene derivatives in moderate to good yields. © 1988.

DOI： 10.1016/S0022-1139(00)81045-3

Scopus

researchmap

Language：English  

1-Substituted F-1-alkenyl phosphates, easily prepared from F-alkyl ketones and the sodium salt of diethyl phosphite, were allowed to react with various phosphonium ylides in tetrahydrofuran or hexane at room temperature or at the reflux temperature of the solvent to lead to the corresponding polyfluorinated 1,3-diene derivatives in moderate to good yields. © 1988.

DOI： 10.1016/S0022-1139(00)81045-3

Scopus

researchmap

Language：English  

Various chlorodifluoromethyl ketones react readily with dialkyl or diaryl phosphites in the presence of triethylamine at the reflux temperature of tetrahydrofuran to give the corresponding dialkyl or diaryl 1-substituted-2,2-difluoroethenyl phosphates in good yields, whereas the similar reaction conducted at lower temperature (0-20 °C) affords 1-(chlorodifluoromethyl)-1-hydroxyalkanephosphonates almost exclusively. The latter compounds are converted to the former enol phosphates by the treatment with triethylamine or sodium methoxide in refluxing tetrahydrofuran. © 1988.

DOI： 10.1016/S0022-1139(00)83035-3

Scopus

researchmap

Language：English  

Various chlorodifluoromethyl ketones react readily with dialkyl or diaryl phosphites in the presence of triethylamine at the reflux temperature of tetrahydrofuran to give the corresponding dialkyl or diaryl 1-substituted-2,2-difluoroethenyl phosphates in good yields, whereas the similar reaction conducted at lower temperature (0-20 °C) affords 1-(chlorodifluoromethyl)-1-hydroxyalkanephosphonates almost exclusively. The latter compounds are converted to the former enol phosphates by the treatment with triethylamine or sodium methoxide in refluxing tetrahydrofuran. © 1988.

DOI： 10.1016/S0022-1139(00)83035-3

Scopus

researchmap

Language：English  

Various chlorodifluoromethyl ketones react readily with dialkyl or diaryl phosphites in the presence of triethylamine at the reflux temperature of tetrahydrofuran to give the corresponding dialkyl or diaryl 1-substituted-2,2-difluoroethenyl phosphates in good yields, whereas the similar reaction conducted at lower temperature (0-20 °C) affords 1-(chlorodifluoromethyl)-1-hydroxyalkanephosphonates almost exclusively. The latter compounds are converted to the former enol phosphates by the treatment with triethylamine or sodium methoxide in refluxing tetrahydrofuran. © 1988.

DOI： 10.1016/S0022-1139(00)83035-3

Scopus

researchmap

Language：English   Publisher：The Chemical Society of Japan  

The treatment of F-alkyl ketones with sodium diethyl phosphite in tetrahydrofuran at −10 to 0 °C gave high yields of 1-substituted F-1-alkenyl phosphates, which readily reacted with amidine or hydrazine derivatives at room temperature to afford the corresponding fluorinated pyrimidines or pyrazoles, respectively, in good to excellent yields.

DOI： 10.1246/cl.1988.819

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

The treatment of F-alkyl ketones with sodium diethyl phosphite in tetrahydrofuran at −10 to 0 °C gave high yields of 1-substituted F-1-alkenyl phosphates, which readily reacted with amidine or hydrazine derivatives at room temperature to afford the corresponding fluorinated pyrimidines or pyrazoles, respectively, in good to excellent yields.

DOI： 10.1246/cl.1988.819

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

The treatment of F-alkyl ketones with sodium diethyl phosphite in tetrahydrofuran at −10 to 0 °C gave high yields of 1-substituted F-1-alkenyl phosphates, which readily reacted with amidine or hydrazine derivatives at room temperature to afford the corresponding fluorinated pyrimidines or pyrazoles, respectively, in good to excellent yields.

DOI： 10.1246/cl.1988.819

CiNii Article

researchmap

Language：English  

Chlorodifluoromethyl ketones efficiently underwent the aldol reaction with a variety of aldehydes or ketones in the presence of zinc, a catalytic amount of copper(I) chloride or silver(I) acetate and molecular sieves to give the corresponding α,α-difluoro-β-hydroxy ketones in good to excellent yields. © 1987.

DOI： 10.1016/S0040-4039(00)96894-1

Scopus

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1987.1621

Web of Science

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1987.1621

Web of Science

researchmap

Language：English  

1-Substituted F-1-alkenyl phosphate, readily available from F-alkyl ketones and diethyl phosphite, undergo the dephosphorylation by the action of copper(I) or copper(II) bromide and lithium aluminium hydride at -78 °C followed by hydrolysis to give the corresponding 1-hydryl-F-alkyl ketones in good to excellent yields. © 1987.

DOI： 10.1016/S0022-1139(00)83092-4

Scopus

researchmap

Language：English  

1-Substituted F-1-alkenyl phosphate, readily available from F-alkyl ketones and diethyl phosphite, undergo the dephosphorylation by the action of copper(I) or copper(II) bromide and lithium aluminium hydride at -78 °C followed by hydrolysis to give the corresponding 1-hydryl-F-alkyl ketones in good to excellent yields. © 1987.

DOI： 10.1016/S0022-1139(00)83092-4

Scopus

researchmap

Language：English   Publisher：CHEMICAL SOC JAPAN  

DOI： 10.1246/cl.1987.1621

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/S0040-4039(00)96337-8

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/S0040-4039(00)96337-8

Web of Science

researchmap

Language：English   Publisher：PERGAMON-ELSEVIER SCIENCE LTD  

DOI： 10.1016/S0040-4039(00)96337-8

Web of Science

researchmap

Language：English   Publisher：The Chemical Society of Japan  

A variety of alkenes and alkynes efficiently undergo the perfluoroalkylation with F-alkyl iodides in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) in hexane to give good yields of the corresponding F-alkylated alkyl and alkenyl iodides, respectively.

DOI： 10.1246/cl.1986.1895

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

A variety of alkenes and alkynes efficiently undergo the perfluoroalkylation with F-alkyl iodides in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) in hexane to give good yields of the corresponding F-alkylated alkyl and alkenyl iodides, respectively.

DOI： 10.1246/cl.1986.1895

CiNii Article

researchmap

Language：English   Publisher：The Chemical Society of Japan  

A variety of alkenes and alkynes efficiently undergo the perfluoroalkylation with F-alkyl iodides in the presence of a catalytic amount of tetrakis(triphenylphosphine)palladium(0) in hexane to give good yields of the corresponding F-alkylated alkyl and alkenyl iodides, respectively.

DOI： 10.1246/cl.1986.1895

CiNii Article

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap