担当区分：筆頭著者,　責任著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Wiley  

DOI： 10.1002/ejic.201901120

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その他リンク： http://onlinelibrary.wiley.com/wol1/doi/10.1002/ejic.201901120/fullpdf

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：American Chemical Society (ACS)  

DOI： 10.1021/acs.orglett.0c00289

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.orglett.7b04022

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Royal Society of Chemistry  

An enantioselective aza-Friedel Crafts reaction of cyclic 4-aryl-3-oxo-1,2,5-thiadiazol-1,1-oxides as cyclic ketimines with indoles was developed. High enantioselectivities were observed for the reaction of various cyclic ketimines with indoles using chiral imidazoline-phosphoric acid catalysts. The obtained products can be converted to chiral α-amino amide and hydantoin.

DOI： 10.1039/c8cc00594j

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

The first highly enantioselective reaction of allenylnitriles with imines has been developed. Excellent yields and enantioselectivities were observed for the reaction with various imines using chiral Phebim-Pd-II complexes. This process offers a simple and efficient synthetic route for various functionalized alpha-vinylidene-beta-aminonitriles and their derivatives.

DOI： 10.1002/anie.201702429

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

The enantioselective oxidative ring-opening reaction of aziridines with alpha-nitroacetates has been developed. Good yields and enantioselectivity were observed for the reaction of various aziridines using a novel cinchona alkaloid amide/NiBr2 catalyst. Both enantiomers of products could be obtained by using pseudoenantiomeric chiral catalysts. This process offers an efficient route for the synthesis of alpha-aminoketones.

DOI： 10.1021/acs.orglett.6b03346

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：CHEMICAL SOC JAPAN  

We report the synthesis and luminescent properties of halide-bridged tricopper(I) complexes with a polyaza cryptand having three 2,6-bis(aminomethyl)pyridyl spacers. The asymmetric {Cu3X3} structure was formed in the ligand shell, and emitted in both of the solid and solution states. DFT calculation and (HNMR)-H-1 spectroscopic studies were performed on these luminescent cage-type compounds.

DOI： 10.1246/cl.160105

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

We disclose herein an efficient enantioselective conjugate addition reaction between coumarin-3-carboxylic acids and malonic acid half thioesters (MAHTs). The reaction was catalyzed by N-heteroarenesulfonyl Cinchona alkaloid amides to afford double-decarboxylative conjugate addition products in good yield with high enantioselectivity. The reaction of various coumarin-3-carboxylic acids with MAHTs gave products in high yield with high enantioselectivity.

DOI： 10.1002/adsc.201600040

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/anie.201503098

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/chem.201501351

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

To understand the role of the unique equatorial coordination environment at the active center in nickel superoxide dismutase (NiSOD), we prepared a novel Ni(II) complex with an amino-carboxamido dithiolato-type square-planar ligand (1, [Ni2+(L-1)](-)) as a model of the NiSOD active site. Complex 1 has a low-spin square-planar structure in all solvents. Interestingly, the absorption wavelength and nu(C=O) stretching vibrations of 1 are affected by solvents. This provides an indication that the carbonyl oxygens participate in hydrogen-bonding interactions with solvents. These interactions are reflected in the redox potentials; the peak potential of an anodic wave (E-pa) values of Ni(II)/Ni(III) waves for 1 are shifted to a positive region for solvents with higher acceptor numbers. This indicates that the disproportionation of superoxide anion by NiSOD may be regulated by hydrogen-bonding interactions between the carboxamido carbonyl and electrophilic molecules through fine-tuning of the redox potential for optimal SOD activity. Interestingly, the E-pa value of the Ni(III)/Ni(II) couple in 1 in water (+0.303 V vs normal hydrogen electrode (NHE)) is similar to that of NiSOD (+0.290 V vs NHE). We also investigated the superoxide-reducing and -oxidizing reactions of 1. First, 1 reacts with superoxide to yield the superoxide-bound Ni(II) species (UV-vis: 425, 525, and similar to 650 nm; electron paramagnetic resonance (EPR) (4 K): g(//) = 2.21, g(perpendicular to) = 2.01; resonance Raman: nu(O-16-O-16)/nu(O-18-O-18) = 1020/986 cm(-1)), which is then oxidized to Ni(III) state only in the presence of both a proton and 1-methylirnidazole, as evidenced by EPR spectra. Second, EPR spectra indicate that the oxidized complex of 1 with 1-methylimidazole at the axial site can be reduced by reaction with superoxide. The Ni(III) complex with 1-methylimidazole at the axial site does not participate in any direct interaction with azide anion (pK(a) 4.65) added as mimic of superoxide (pK(a) 4.88). According to these data, we propose the superoxide disproportionation mechanism in superoxide-reducing and -oxidizing steps of NiSOD in both Ni(II) and Ni(III) states.

DOI： 10.1021/ic402574d

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/anie.201309021

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

The synthesis, structures, and reactivity of dinuclear Fe-0 complexes of N-heterocyclic carbenes (NHCs, denoted as L) are reported. The NHC adducts of ferric chloride (L)FeCl3 were prepared from the reactions of FeCl3 with L in toluene. The reduction of (L)FeCl3 with KC8 resulted in the formation of the dinuclear Fe-0 complexes Fe-2{mu-eta(1)(C):,eta(6)(arene)-L}(2) (2a, L = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes); 2b, L = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr)), in which NHC ligands bridge two iron atoms using one of the arene rings as an eta(6) ligand. Their magnetic properties are different: 2a is paramagnetic and 2b is diamagnetic. The dinuclear complexes 2a,b serve as precursors for monomeric (NHC)Fe-0 species, and treatment of 2a,b with 1 atm of CO led to the formation of (L)Fe(CO)(4). Complex 2a was found to react with 1-azidoadamantane, giving rise to the dinuclear tetrazene complex (IMes)Fe(mu-NAd)(2)Fe(AdNNNNAd) (4).

DOI： 10.1021/om401039z

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

A nitride complex [K(thf)(2)](2)[{(O-3)Nb}(2)(-N)(2)] (2), prepared from [K(DME)](2)[{(O-3)Nb}(2)(-H)(4)] (1) and N-2, was protonated with 2,6-lutidinium chloride to yield ammonia and [(O-3)NbCl3](-) (3), where H-3[O-3] = tris(3,5-di-tert-butyl-2-hydroxy phenyl)methane. The reaction of 3 with KBHEt3 regenerated [K(DME)](2)[{(O-3)Nb}(2)(-H)(4)] (1), thereby completing a synthetic cycle for the conversion of N-2 to NH3. Alkylation of 2 with methyl iodide led to formation of [K(thf)][{(O-3)Nb}(2)(-N)(-NMe)] (4) and [{(O-3)Nb}(2)(-NMe)(2)] (5). Treatment of 5 with pyridine afforded a terminal imide complex [(O-3)Nb=NMe(py)(2)] (6). The imide monomer 6 reacted with CO2 to give [(O-3)Nb{(MeN)(2)CO}(py)] (7) and [{(O-3)Nb}(2)(-O)(2)] (8) in a 2:1 ratio, while the reaction of 6 with p-TolNCO gave an asymmetric ureate complex [(O-3)Nb{p-TolNC(O)NMe}(py)] (9).

DOI： 10.1002/ejic.201300172

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

A half-sandwich, coordinatively unsaturated N-heterocyclic carbene complex of iron with a metallacycle was found to cleave the Si-H bonds of hydrosilanes to give 16-electron iron-silyl complexes. The reactions of silyl complexes with H-2 led to the formation of dihydride complexes, in which hydride ligands weakly interact with the silicon atom. The molecular structures of these new complexes have been determined by means of X-ray crystallography.

DOI： 10.1002/ejic.201300045

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

The use of a sterically demanding aryloxide ligand allows us to isolate a tetrakis(aryloxide)diniobium complex bridged by four hydride ligands. This hydride aryloxide undergoes reduction of CO via hydrogenation and deoxygenation, resulting in formation of a methylidene species. Further carbonylation gives a vinylidene complex.

DOI： 10.1039/c2dt32798h

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

The reactions of the half-sandwich iron(II) complex [FeCl(Cp*)(tmeda)] (1; Cp*=?5-C5Me5, TMEDA=N,N,N',N'-tetramethylethylenediamine) with potassium naphthalenide or potassium anthracenide gave the diamagnetic complexes [(Cp*)Fe(mu-polyarene)Fe(Cp*)] (polyarene=naphthalene (2), anthracene (3?a)), which have two {(Cp*)Fe} units bound to opposite faces of the polyarene. One of two {(Cp*)Fe} units in 3?a is located over the central ring of anthracene while the other is positioned over an outer ring. The {(Cp*)Fe} unit bound to the central ring of 3?a migrates to the outer ring upon heating in the solid state to give the isomer 3?b. The electrochemical potential separations between successive one-electron redox events for complexes 2 and 3?b are large. The mixed valence complexes [2]+ and [3b]+ were synthesized by chemical oxidation. The mixed-valence complex [3b]+ is charge delocalized on the Mossbauer timescale at 78 K, and its absorption spectrum shows an intervalence charge-transfer band. Complex [2]+ exhibits two absorption bands in the near-IR region and a slightly broadened doublet in the Mossbauer spectrum. DFT calculations were carried out to examine the electronic structures of these dinuclear iron(I) complexes to elucidate the factors responsible for their diamagnetism and to determine the degree of charge delocalization in the mixed-valence complexes.

DOI： 10.1002/asia.201101037

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ROYAL SOC CHEMISTRY  

Reactions of the cyclometalated hydride complexes with diazo and azide substrates are reported. While diazoalkane undergoes four-electron N-N bond cleavage, azides undergo two-electron N-2 extrusion.

DOI： 10.1039/c2cc32535g

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ELSEVIER SCIENCE SA  

The synthesis and reaction of homoleptic iron(II) complexes with 2,6-di-adamantyl-substituted aryl-oxides [OC6H2-,6-Ad-4-R](-) ([OArAdR](-), Ad = adamantyl, R = Me, Pr-i) are described. Monomeric two-coordinate iron aryloxides Fe(OArAdR)(2)(R = Me, 1; Pr-i, 2) were synthesized by the reaction of Fe [N(SiMe3)(2)](2) with 2 equiv of HOArAdR. Treatment of 1 and 2 with 1-azidoadamantane resulted in intramolecular insertion of an adamantyl nitrene into a methylene C-H bond of the aryloxide adamantyl substituent, yielding the corresponding amine-aryloxide complexes Fe(OArAdR)(OArAdR-NHAd) (R = Me, 3; Pr-i, 4). Molecular structures of all these complexes are reported. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jorganchem.2011.06.049

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Organofluorine compounds are widely used in all aspects of the chemical industry. Although tetrafluoroethylene (TFE) is an example of an economical bulk organofluorine feedstock, the use of TFE is mostly limited to the production of poly(tetrafluoroethylene) and copolymers with other alkenes. Furthermore, no catalytic transformation of TFE that involves carbon-fluorine bond activation has been reported to date. We herein report the first example of a palladium-catalyzed coupling reaction of TFE with arylzinc reagents in the presence of lithium iodide, giving alpha,beta,beta-trifluorostyrene derivatives in excellent yields.

DOI： 10.1021/ja109911p

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

A coordinatively unsaturated iron-methyl complex having an N-heterocyclic carbene ligand, [Cp*Fe(L-Me)Me] (1; Cp*=eta(5)-C5Me5, L-Me=1,3,4,5-tetramethyl-imidazol-2-ylidene), is synthesized from the reaction of [Cp*Fe(TMEDA)Cl] (TMEDA = N,N,N',N'-tetramethylethylenediamine) with methyllithium and L-Me. Complex 1. is found to activate the C H bonds of furan, thiophene, and benzene, giving rise to aryl complexes, [Cp*Fe(L-Me)(aryl)] (aryl=2-furyl (2), 2-thienyl (3), phenyl (4)). The C H bond cleavage reactions are applied to the dehydrogenative coupling of furans or thiophenes with pinacolborane (HBpin) in the presence of tert-butylethylene and a catalytic amount of 1 (10 mol% to HBpin). The borylation of the furan/thiophene or 2-substituted furans/thiophenes occurs exclusively at the 2- or 5-positions, respectively, whereas that of 3-substituted furans/thiophenes takes place mainly at the 5-position and gives a mixture of regioisomers. Treatment of 2 with 2 equiv of HBpin results in the quantitative formation of 2-boryl-furan and the borohydride complex [Cp*Fe(L-Me)(H(2)Bpin)] (5). Heating a solution of 5 in the presence of tert-butylethylene led to the formation of an alkyl complex [Cp*Fe(L-Me)CH(2)CH(2)tBu] (6), which was found to cleave the C H bond of furan to produce 2. On the basis of these results, a possible catalytic cycle is proposed.

DOI： 10.1002/asia.201000140

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

Half-sandwich iron complexes of N-heterocyclic carbenes, Cp*Fe(L-R)CI (2a; L-Mes = 1,3-dimesitylimidazol-2-ylidene, 2b; L-iPr = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene, Cp* = eta(5)-C5Me5), have been synthesized by the reaction of Cp*Fe{N(SiMe3)(2}) (1) with the corresponding imidazolium salts. Treatment of 2a with either methyllithium or phenyllithium replaces the chloride with either a methyl or a phenyl group, generating Cp*Fe(L-Mes)R (3a; R = Me, 3b; R = Ph). These complexes, in turn, undergo cyclometalation at elevated temperatures, and Cp*Fe{k(2)-(C,C)-L'(Mes)} (4; L'(Mes) = CH2C6H2-3,5-Me-2-2-(3-mesityl-imidazol-2-ylidene-1-yl)) was isolated. On the other hand, methylation of 2b at room temperature leads directly to the formation of a cyclometalated complex, Cp*Fe{k(2)-(C,C)-L'(iPr)} (6; L'(iPr) = CH2CH(CH3)(3-isopropyl-4,5-dimethylimidazol-2-ylidene-1-yl)). The Fe(II) center of 6 traps atmospheric dinitrogen reversibly to produce a dinuclear end-on N-2 complex [Cp*Fe{k(2)-(C,C)-L'(iPr)}]2(mu-eta(1):eta(1)-N-2) (7). Complex 6 also promotes C-H bond activation of thiophene, furan, benzothiophene, and benzofuran at room temperature. In these reactions, C-H bond cleavage occurred exclusively at the 2-position of the rings, generating Cp*Fe(L-iPr)(2-C4H3E) (8; E = S, 9; E = O) and Cp*Fe(L-iPr)(2-C8H5E) (10; E = S, 11; E = O), while C-H cleavage took place mainly at the 4-position in the case of pyridine. Coupling reactions between heteroarenes and catecholborane (HBcat) can be carried out by treatment of 6 with heteroarenes followed by the addition of excess HBcat, giving rise to 2-boryl-heteroarenes and the borohydride complex Cp*Fe(L-iPr)(H(2)Bcat) (14).

DOI： 10.1021/ja8063028

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：AMER CHEMICAL SOC  

The coordinatively unsaturated iron(II) amido complex Cp* Fe {N(SiMe3)(2)} ( 1) serves as an efficient precursor for the cleavage of the N-N bond of diphenylhydrazine. The N=N bond of azobenzene was also found to be activated by 1 in the presence of pinacolborane.

DOI： 10.1021/om0602963

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