DOI： 10.1016/j.orgel.2019.06.021

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DOI： 10.1039/c8tc05824e

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DOI： 10.1007/s10847-018-00877-4

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掲載種別：研究論文（学術雑誌）  

© 2019 The Royal Society of Chemistry. The transport properties of 3,10-ditetradecylpicene ((C14H29)2-picene) and [6]phenacene thin-film field-effect transistors (FETs) on Si and plastic substrates are reported, in which SiO2 and parylene are used as gate dielectrics, respectively. These devices show p-channel normally-off FET characteristics. A μ value of 1.34 cm2 V-1 s-1 is obtained in the (C14H29)2-picene thin-film FET, where 500 μm thick polyethylene terephthalate (PET) and 1 μm thick parylene are used as the substrate and gate dielectric, respectively. Moreover, excellent FET performance is obtained in the (C14H29)2-picene thin-film FET using a high-k gate dielectric, ZrO2, which is formed on a 350 μm thick PET substrate, showing p-channel normally-off FET properties and low voltage operation. The μ value reaches 6.31 cm2 V-1 s-1 in the FET device. The FET properties of N,N′-dioctyl-3,4,9,10-perylenedicarboximide (PTCDIC8) thin-film FETs formed on PET are also reported, showing n-channel normally-off FET characteristics. We report a bias stress effect on flexible [6]phenacene thin film FETs that are fabricated on a PEN substrate. Two types of experiments are performed for investigating the bias stress effect on FETs, and the bias stress effect under light irradiation is very different from that under no irradiation. This difference is well explained based on the hole-filling of trap states by electron excitation. We show the characteristics of a complementary MOS inverter (CMOS), constituting a [6]phenecene thin-film FET (p-channel) and a PTCDIC8 thin-film FET (n-channel) formed on the PET and PEN substrates, i.e., a flexible CMOS inverter. The maximum gain reaches 300. Furthermore, we report low-voltage operation for the flexible CMOS inverter, where ZrO2 is used as the gate dielectric. Through this study, we have achieved the fabrication of flexible thin-film FETs with a high μ and low voltage operation, and flexible CMOS inverters with a high gain as well as low operation voltage. This study could provide a basis for future practical/human-compatible electronic devices.

DOI： 10.1039/c8tc05824e

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DOI： 10.1039/c8pp00302e

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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：PERGAMON-ELSEVIER SCIENCE LTD  

We prepared isomeric compounds 2a and 2b having fused skeletons of coumarin and fluorene by photochemical cyclization of olefin 1. They were successfully separated by chromatography, and characterized by NMR spectroscopic and X-ray crystallographic analyses. The molecular structure of 2a was nonplanar due to the repulsion between the carbonyl group of the coumarin moiety and the methylene group at 9-position on the fluorene skeleton whilst that of 2b was planar. They showed different absorption and fluorescence features in solution whereas their spectral profiles of triplet-triplet absorption and phosphorescence were similar to each other. (C) 2018 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.tetlet.2018.02.033

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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：Elsevier Ltd  

Fluorescence properties of phthalimide derivatives (1) incorporating sulfonamide and acetamide functionalities at the 3-position were investigated both in solution and in the solid states to reveal the effects of the amide functionalities on the fluorescence properties. In the solid state, sulfonamides 1a and 1b, respectively, gave off red (λF max 595 nm) and green (λF max 537 nm) emission through an ESIPT process. Acetamides 1c and 1d, respectively displayed blue (λF max 432 nm) and yellow (λF max 560 nm) emission. Through simply modifying the amide functionality, phthalimide 1 displayed multicolor RGBY emission in the solid state.

DOI： 10.1016/j.tetlet.2017.12.049

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DOI： 10.1016/j.jphotochem.2018.04.017

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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  

Small molecules having intense luminescence properties are required to promote biological and organic material applications. We prepared five types of benzamides having pyridine, pyridazine, pyrazine, and pyrimidine rings and successfully converted them into three types of the difluoroboronated complexes, Py@BAs, as novel blue fluorophores. Py@BA having a pyridine moiety (2-Py@BA) showed no fluorescence in solution, whereas Py@BAs of pyridazine and pyrazine moieties (2,3-Py@BA and 2,5-Py@BA, respectively) emitted blue fluorescence with quantum yields of ca. 0.1. Transient absorption measurements using laser flash photolysis of the Py@BAs revealed the triplet formation of 2,3- and 2,5-Py@BAs, while little transient signal was observed for 2-Py@BA. Therefore, the deactivation processes from the lowest excited singlet state of fluorescent 2,3- and 2,5-Py@BAs consist of fluorescence and intersystem crossing to the triplet state while that of the nonfluorescent Py@BA is governed almost entirely by internal conversion to the ground state. Conversely, in the solid state, 2-Py@BA emitted intense fluorescence with a fluorescence quantum yield as high as 0.66, whereas 2,3- and 2,5-Py@BAs showed fluorescence with quantum yields of ca. 0.2. The crystal structure of 2-Py@BA took a herringbone packing motif, whereas those for 2,3- and 2,5-Py@BAs were two-dimensional sheetlike. On the basis of the difference in crystal structures, the emission mechanism in the solid state was discussed.

DOI： 10.1021/acs.inorgchem.7b02013

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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  

An octafluorinated 2,11-diaza[3(2)] paracyclophane derivative 12 was prepared, and its photochemical reaction was investigated. Upon irradiation at 300 nm, the fluorinated azacyclophane 12 underwent efficient photodimerization of the benzene cores to afford the corresponding photoisomer 13, which possessed cage diene benzene dimer structure (pentacyclo[6.4.0.0.(2,7)0.(3,12)0(6,9)] dodeca-4,10-diene skeleton). The cage diene structure was established by single-crystal X-ray diffraction analysis. The cage diene 13 thermally isomerized to a syn-o,o'-dibenzene isomer 22. The activation parameters for the thermal isomerization were determined to be E-a = 121 kJ mol(-1), Delta H-not equal = 118 kJ mol(-1), Delta S-(293 K)(not equal) = 22 J mol(-1) K-1, and Delta G(not equal) ((293 K)) = 111 kJ mol(-1). It was revealed that, by photoirradiation at 300 nm, the syn-o,o'-dibenzene isomer 22 underwent facile intramolecular [pi 4s + pi 4s] cycloaddition to reproduce the cage diene isomer 13

DOI： 10.1002/poc.3726

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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：GEORG THIEME VERLAG KG  

Various phenacenes possessing chrysene, picene, and fulminene frameworks were prepared by using a continuous-flow synthetic protocol in which Wittig reaction affording diarylethenes and their Mallory photocyclization producing phenacene skeletons were sequentially performed. The Wittig reaction solution, containing the diarylethene obtained from an arylaldehyde and an arylmethyltriphenylphosphonium salt, was mixed with an iodine solution in the flow system and, subsequently, the solution was subjected to the photoreaction. Desired phenacenes were obtained with high to moderate chemical yield. For the present protocol, isolation of the intermediary diarylethene, which is the key precursor of the phenacene, is unnecessary. The approach provides a convenient method to supply a variety of phenacene samples, which are needed for initial systematic surveys in material science.

DOI： 10.1055/s-0036-1588775

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7pp00040e

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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  

Phenacenes represent.a class of simple hydrocarbons with appealing physical properties ranging from high charge mobility to superconductivity in combination with chemical robustness that are easily modified to serve as versatile building blocks for tailored structures. As a promising candidate for applications in organic devices, phenacenes are the focus of recent investigations. Thereby, the initial growth behavior starting from a single molecule is controversial. Here, we address the growth of [7]phenacene and [9]phenacene on a Ag(111) surface, studying the details of the initial stage of growth by scanning tunneling microscopy. According to our results, a previously introduced model involving a coverage-dependent phase change with the out-of-plane rotation of molecules in the initial growth stage can be disregarded. Instead, we find evidence for the formation of a new phase on top of an in-plane wetting layer during the initial stage of growth.

DOI： 10.1021/acs.jpcc.7b01806

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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  

We prepared a variety of coumarin derivatives having expanded pi-electron systems along the direction crossing the C-3-C-4 bond of the coumarin skeleton via a photochemical cyclization process and investigated their photophysical features as a function of the number (n) of the added benzene rings based on emission and transient absorption measurements. Upon increasing n, the fluorescence quantum yields of the pi-extended coumarins increased. Expanding the p-electron system on the C-3-C-4 bond of the coumarin skeleton was found to be efficient for increasing the fluorescence ability more than that on the C-7-C-8 bond. Introducing the methoxy group at the 7-position was also efficient for enhancing the fluorescence quantum yield and rate of the expanded coumarins. The non-radiative process from the fluorescence state was not substantially influenced by the expanded pi-electron system. The competitive process with the fluorescence was found to be intersystem crossing to the triplet state based on the observations of the triplet-triplet absorption. The effects of the expanded pi-electron systems on the fluorescence ability were investigated with the aid of TD-DFT calculations.

DOI： 10.1039/c6pp00399k

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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：IOP PUBLISHING LTD  

Potassium-doped picene (K(3.0)picene) with a superconducting transition temperature (TC) as high as 14 K at ambient pressure has been prepared using an annealing technique. The shielding fraction of this sample was 5.4% at 0 GPa. The TC showed a positive pressure-dependence and reached 19 K at 1.13 GPa. The shielding fraction also reached 18.5%. To investigate the chemical composition and the state of the picene skeleton in the superconducting sample, we used energy-dispersive x-ray (EDX) spectroscopy, MALDI-time-of-flight (MALDI-TOF) mass spectroscopy and x-ray diffraction (XRD). Both EDX and MALDI-TOF indicated no contamination with materials other than K-doped picene or K-doped picene fragments, and supported the preservation of the picene skeleton. However, it was also found that a magnetic K-doped picene sample consisted mainly of picene fragments or K-doped picene fragments. Thus, removal of the component contributing the magnetic quality to a superconducting sample should enhance the volume fraction.

DOI： 10.1088/0953-8984/28/44/444001

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DOI： 10.1088/0953-8984/28/33/334001

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.tetlet.2016.03.011

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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：NATURE PUBLISHING GROUP  

the widespread interest in the chemistry, physics and materials science of such molecules and their potential applications. In particular, extended phenacene molecules, consisting of coplanar fused benzene rings in a repeating W-shaped pattern have attracted much attention because field-effect transistors (FETs) using phenacene molecules show promisingly high performance. Until now, the most extended phenacene molecule available for transistors was [8] phenacene, with eight benzene rings, which showed very high FET performance. Here, we report the synthesis of a more extended phenacene molecule, [9] phenacene, with nine benzene rings. Our synthesis produced enough [9] phenacene to allow the characterization of its crystal and electronic structures, as well as the fabrication of FETs using thin-film and single-crystal [9] phenacene. The latter showed a field-effect mobility as high as 18 cm(2) V-1 s(-1), which is the highest mobility realized so far in organic single-crystal FETs.

DOI： 10.1038/srep21008

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c5pp00454c

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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  

A series of amino-2,3-naphthalimide derivatives having the amino functionality at 1-, 5-and 6-positions (1ANI, 5ANI and 6ANI, respectively) were prepared, and their photophysical properties were systematically investigated based on the measurements of steady-state absorption and fluorescence spectra, fluorescence lifetimes as well as transient absorption spectra. The ANIs efficiently fluoresced in solution, and the emission spectra appreciably shifted depending on the solvent polarity. 1ANI displayed only a slight fluorescence red-shift upon increasing the solvent polarity. In contrast, 5ANI and 6ANI showed marked positive solvatofluorochromism with large Stokes shifts displaying multicolour fluorescence; the fluorescence colours of 5ANI and 6ANI varied from violet-blue in hexane to orange-red in methanol. 5ANI and 6ANI, thus, serve as micro-environment responding fluorophores. In methanol, the intensity of the fluorescence emission band of 5ANI and 6ANI significantly reduced. Based on the fluorescence quantum yields and lifetimes, and transient absorption measurements, it has been revealed that internal conversion from the S-1 state of ANIs to the ground state was accelerated by the protic medium, resulting in a reduction in their fluorescence efficiency, while intersystem crossing from the S1 state to a triplet state was not responsible for the decrease of fluorescence intensity.

DOI： 10.1039/c6pp00048g

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c6pp00089d

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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/jp511105v

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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  

Field-effect transistors (FETs) with single crystals of a new phenacene-type molecule, [8]phenacene, were fabricated and characterized. This new molecule consists of a phenacene core of eight benzene rings, with an extended p-conjugated system, which was recently synthesized for use in an FET by our group. The FET characteristics of an [8]phenacene single-crystal FET with SiO2 gate dielectrics show typical p-channel properties with an average field-effect mobility, <mu >, as high as 3(2) cm(2) V-1 s(-1) in two-terminal measurement mode, which is a relatively high value for a p-channel single-crystal FET. The hmi was determined to be 6(2) cm(2) V-1 s(-1) in four-terminal measurement mode. Low-voltage operation was achieved with PbZr0.52Ti0.48O3 (PZT) as the gate dielectric, and an electric-double-layer (EDL) capacitor. The <mu > and average values of absolute threshold voltage, <vertical bar V-th vertical bar >, were 1.6(4) cm(2) V-1 s(-1) and 5(1) V, respectively, for PZT, and 4(2) x 10(-1) cm(2) V-1 s(-1) and 2.38(4) V, respectively, for the EDL capacitor; these values were evaluated in two-terminal measurement mode. The inverter circuit was fabricated using [8]phenacene and N, N'-1H, 1H-perfluorobutyldicyanoperylene-carboxydi-imide single-crystal FETs. This is the first logic gate circuit using phenacene molecules. Furthermore, the relationship between mu and the number of benzene rings was clarified based on this study and the previous studies on phenacene single-crystal FETs.

DOI： 10.1039/c5tc00960j

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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  

The continuous flow reaction technique has been applied to the photocyclization of 1,2-diarylethenes, the so-called Mallory reaction, to afford phenacenes in high chemical yields and efficiencies (114-288 mg h(-1)). The present technique will allow us to produce several grams of phenacenes at a time.

DOI： 10.1246/cl.140182

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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：NATURE PUBLISHING GROUP  

A new phenacene-type molecule, [8] phenacene, which is an extended zigzag chain of coplanar fused benzene rings, has been synthesised for use in an organic field-effect transistor (FET). The molecule consists of a phenacene core of eight benzene rings, which has a lengthy pi-conjugated system. The structure was verified by elemental analysis, solid-state NMR, X-ray diffraction (XRD) pattern, absorption spectrum and photoelectron yield spectroscopy (PYS). This type of molecule is quite interesting, not only as pure chemistry but also for its potential electronics applications. Here we report the physical properties of [8] phenacene and its FET application. An [8] phenacene thin-film FET fabricated with an SiO2 gate dielectric showed clear p-channel characteristics. The highest m achieved in an [8] phenacene thin-film FET with an SiO2 gate dielectric is 1.74 cm(2) V-1 s(-1), demonstrating excellent FET characteristics; the average mu was evaluated as 1.2(3) cm(2) V-1 s(-1). The mu value in the [8] phenacene electric-double-layer FET reached 16.4 cm(2) V-1 s(-1), which is the highest reported in EDL FETs based on phenacene-type molecules; the average m was evaluated as 8(5) cm(2) V-1 s(-1). The mu values recorded in this study show that [8] phenacene is a promising molecule for transistor applications.

DOI： 10.1038/srep05330

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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：NATURE PUBLISHING GROUP  

Field-effect transistors (FETs) were fabricated with a thin film of 3,10-ditetradecylpicene, picene-(C14H29)(2), formed using either a thermal deposition or a deposition from solution (solution process). All FETs showed p-channel normally-off characteristics. The field-effect mobility, m, in a picene-(C14H29)(2) thin-film FET with PbZr0.52Ti0.48O3 (PZT) gate dielectric reached similar to 21 cm(2) V-1 s(-1), which is the highest mu value recorded for organic thin-film FETs; the averagem mu value (<mu >) evaluated from twelve FET devices was 14(4) cm(2)V(-1) s(-1). The, m. values for picene-(C14H29)(2) thin- film FETs with other gate dielectrics such as SiO2, Ta2O5, ZrO2 and HfO2 were greater than 5 cm(2) V-1 s(-1), and the lowest absolute threshold voltage, vertical bar V-th vertical bar, (5.2 V) was recorded with a PZT gate dielectric; the average jVthj for PZT gate dielectric is 7(1) V. The solution-processed picene-(C14H29)(2) FET was also fabricated with an SiO2 gate dielectric, yielding mu = 3.4 x 10(-2) cm(2) V-1 s(-1). These results verify the effectiveness of picene-(C14H29)(2) for electronics applications.

DOI： 10.1038/srep05048

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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：ELSEVIER SCIENCE BV  

Fluorescence, fluorescence excitation and absorption spectra of picene have been measured in the vapor phase. It is shown that picene vapor exhibits weak fluorescence from the S-2(pi, pi*) state in addition to strong S-1(pi, pi*) fluorescence. The S-2/S-1 fluorescence yield ratio is evaluated to be approximately 1.3 x 10(-2) following the excitation into the S-3 state. It is shown that the relative S-2 fluorescence quantum yield increases with increasing excitation energy, while the S-1 fluorescence yield is nearly invariant. Mechanism of the appearance of the S-2 fluorescence of picene vapor is discussed. (c) 2013 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.cplett.2013.03.055

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記述言語：英語   出版者・発行元：SPRINGER  

Facile synthesis of fulminene ([6]phenacene) was achieved through the Mallory reaction of 1-(1-naphthyl)-2-(1-phenanthryl)ethene or the 9-fluorenone-sensitized photo-ring-closure of 1-(1-naphthyl)-2-(1-phenanthryl)ethane. The electronic spectral properties of fulminene were investigated for the first time using photoluminescence as well as transient absorption spectroscopy. The spectral features were compared with those of a series of lower phenacene homologs such as phenanthrene ([3]phenacene), chrysene ([4]phenacene), and picene ([5]phenacene). For the [n]phenacene series, both the fluorescence and phosphorescence bands linearly red-shifted with an increase in the number of the benzene rings (n). Trends in the energy levels of the excited singlet (E (S)) and the triplet (E (T)) states were expressed as E (s) = -2.6n + 89.1 (kcal mol(-1)) and E (T) = -1.8n + 66.2 (kcal mol(-1)), respectively. In the case of fulminene, laser flash photolysis displayed a transient spectrum with an absorption maximum (lambda (max) (T-T) ) at 675 nm, which was assigned as the triplet fulminene excited state. The lambda (max) (T-T) values for the [n]phenacene series showed a linear correlation as a function of the ring number n, given by an equation, lambda (max) (T-T) = 60n + 318 (nm).

DOI： 10.1007/s11164-012-0639-1

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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  

Field-effect transistors (FETs) based on [6]phenacene thin films were fabricated with SiO2 and parylene gate dielectrics. These FET devices exhibit field-effect mobility in the saturation regime as high as 7.4 cm(2) V-1 s(-1), which is one of the highest reported values for organic thin-film FETs. The two- and four-probe mobilities in the linear regime display nearly similar values, suggesting negligible contact resistance at 300 K. FET characteristics were investigated using two-probe and four-probe measurement modes at 50-300 K. The two-probe mobility of the saturation regime can be explained by the multiple shallow trap and release model, while the intrinsic mobility obtained by the four-probe measurement in the linear regime is better explained by the phenomenon of transport with charge carrier scattering at low temperatures. The FET device fabricated with a parylene gate dielectric on polyethylene terephthalate possesses both transparency and flexibility, implying feasibility of practical application of [6] phenacene FETs in flexible/transparent electronics. N-channel FET characteristics were also achieved in the [6] phenacene thin-film FETs using metals that possess a small work function for use as source/drain electrodes.

DOI： 10.1039/c3cp53598c

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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 INST PHYSICS  

Transistor characteristics are studied for field-effect transistors (FETs) with thin films of [6]phenacene, which has six benzene rings and W-shape structure. The molecular alignment preferable for FET transport is found to be formed in [6]phenacene thin films. The transistor shows clear p-channel FET characteristics with field-effect mobility mu as high as 3.7 cm(2) V-1 s(-1). The similar O-2 sensing properties to picene FET are observed in [6]phenacene thin film FET. The bias stress properties are observed in [6]phenacene thin film FET. The pulse-voltage application suppresses the bias-stress effect and it enables a continuous O-2 sensing in [6]phenacene FET. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4747201]

DOI： 10.1063/1.4747201

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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  

The reaction of o-methylphenylnitrene in the presence of alcohol and amine was expected to give isomeric pairs of 3- and 7-methyl-3H-azepine derivatives. The formation ratio between these isomers was found to be obviously influenced by reaction temperature, that is, reaction at 150 degrees C gave 7-methyl-3H-azepine derivative, however, it became minor under 70 degrees C in both media. The ratio between 3- and 7-methyl derivatives is explained by a scheme of kinetic- and thermodynamic-controlled product distribution from o-methylphenylnitrene to 3- and 7-methyldehydroazepine intermediates which are trapped by nucleophilic media to give 3- and 7-methyl-3H-azepine derivatives.

DOI： 10.1246/cl.2012.400

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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：ELSEVIER SCIENCE SA  

The Cd(P-3(1))- and Hg(P-3(1))-photosensitized emissions of some secondary and tertiary alkyl- and silylamines have been investigated under conditions of steady illumination at 493 and 298 K, respectively. The emission bands were observed at around 440 nm in the cadmium-photosensitized reactions of these amines. In contrast, no appreciable emission bands were observed in the mercury-photosensitized reactions of these amines. However, upon addition of tert-butyl alcohol to the amine-mercury system, an emission band evolved at around 350 nm in the mercury-photosensitization. The peak-wavelengths for secondary and tertiary alkyl- and silylamines are slightly shorter than the values predicted from the correlations between the peak wavelength and the first ionization energy obtained in the cadmium- and mercury-photosensitized luminescence of ammonia and primary amines. The quenching efficiencies of the cadmium and mercury resonance lines by secondary alkyl- and silylamines are higher than those by tertiary alkyl- and silylamines. These observations suggest that the steric hindrance by the alkyl and silyl groups to the approach of the nitrogen atom in the amines to excited cadmium and mercury atoms seems to be an important factor for the stabilization of the exciplexes and the quenching of the resonance lines. The behavior of silylamines is similar to that of alkylamines in cadmium- and mercury-photosensitized reactions. (C) 2011 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.jphotochem.2011.11.010

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c2cc17502a

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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：PERGAMON-ELSEVIER SCIENCE LTD  

The cause of regioselectivity for the formation of 3-alkyl- and/or 7-alkyl-3H-azepine derivatives via the intramolecular insertion reaction of o-alkylphenylnitrene, which is generated by an action of Buy on o-alkylnitrobenzene, in the presence of alcohol found to be elucidated by the steric effects of an alcohol adduct on the dehydroazepine intermediate. Observed selectivity is confirmed both by changing the bulkiness of the o-alkyl group of phenylnitrene and that of alcohol as a nucleophile.

DOI： 10.3987/COM-11-12172

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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  

A facile formation of picene was achieved by photosensitization of 1,2-di(1-naphthyl)ethane using 9-fluorenone as a sensitizer. This sensitized photoreaction is the first photochemical cyclization of ethylene-bridged naphthalene moieties to afford the picene skeleton. 5,8-Dibromopicene, prepared by this procedure using 1,2-di[1-(4-bromonaphthyl)]ethane as the substrate, was readily converted to novel functionalized picenes by conventional substitution and cross-coupling reactions.

DOI： 10.1021/ol200874q

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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  

Phthalide derivatives incorporating mono- and di-picolylamino functionalities at the 6-position have been prepared as novel fluoroionophores and their fluorescence responses to metal cations have been investigated. These phthalides not only exhibited efficient fluorescence in an aqueous medium but also displayed fluorescence on-off response upon addition of transition-metal cations, namely Cu(2+). The 6-aminophthalide fluorophore served as the core of the fluorescent probes although it has rarely been applied to a chemosensor. To the best of our knowledge, these modified phthalides are the first 6-aminophthalide-derived fluorometric probes for metal cations, namely Cu(2+).

DOI： 10.1039/c1an15239d

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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  

New carbon-based superconductors are synthesized by intercalating metal atoms into the solid-phase hydrocarbons picene and coronene. The highest reported superconducting transition temperature, T-c, of a hydrocarbon superconductor is 18 K for K(3)picene. The physics and chemistry of the hydrocarbon superconductors are extensively described for Axpicene (A: alkali and alkali earth-metal atoms) for x = 0-5. The theoretical picture of their electronic structure is also reviewed. Future prospects for hydrocarbon superconductors are discussed from the viewpoint of combining electronics with condensed-matter physics: modification of the physical properties of hydrocarbon solids is explored by building them into a field-effect transistor. The features of other carbon-based superconductors are compared to clarify the nature of hydrocarbon superconductors.

DOI： 10.1039/c1cp20961b

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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：ELSEVIER SCIENCE BV  

O-2 gas sensing behaviors are studied in picene thin film field-effect transistors (FETs) with hydrophobic polymer (Cytop(TM) or polystyrene) coated SiO2 gate dielectrics. Picene thin film FETs show a rapid reduction of hysteresis in transfer curves recorded in forward and reverse measurement modes, compared to a picene FET with hexamethydisilazane-coated SiO2. The picene FETs show very sensitive O-2 gas sensing effects down to similar to 10 ppm. A quantitative analysis is presented of the gate voltage (V-G) dependent mobility induced by O-2 exposure, i.e., the suppression of drain current at high V-G. (C) 2010 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.orgel.2010.06.003

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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：NATURE PUBLISHING GROUP  

Efforts to identify and develop new superconducting materials continue apace, motivated by both fundamental science and the prospects for application. For example, several new superconducting material systems have been developed in the recent past, including calcium-intercalated graphite compounds(1), boron-doped diamond(2) and-most prominently-iron arsenides such as LaO(1-x)F(x)FeAs (ref. 3). In the case of organic superconductors, however, no new material system with a high superconducting transition temperature (T(c)) has been discovered in the past decade. Here we report that intercalating an alkali metal into picene, a wide-bandgap semiconducting solid hydrocarbon, produces metallic behaviour and superconductivity. Solid potassium-intercalated picene (K(x)picene) shows T(c) values of 7K and 18 K, depending on the metal content. The drop of magnetization in Kxpicene solids at the transition temperature is sharp (<2 K), similar to the behaviour of Ca-intercalated graphite(1). The Tc of 18K is comparable to that of K-intercalated C(60) (ref. 4). This discovery of superconductivity in K(x)picene shows that organic hydrocarbons are promising candidates for improved T(c) values.

DOI： 10.1038/nature08859

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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 INST PHYSICS  

Flexible picene thin film field-effect transistors (FETs) have been fabricated with parylene gate dielectric on polyethylene terephthalate substrates. The picene thin film FETs show p-channel output/transfer characteristics and the field-effect mobility mu reaches similar to 1 cm(2) V(-1) s(-1) in vacuum. The FET shows a clear O(2) gas sensing effect and negligible hysteresis in the transfer curves, indicating a possible application of the transistor as O(2) selective gas sensor. Furthermore, it has been found that the parylene gate dielectric can eliminate a reduction in on-state drain current caused by continuous bias-voltage application which is observed if a SiO(2) gate dielectric is used.

DOI： 10.1063/1.3360223

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掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jp1041475

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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 INST PHYSICS  

Low voltage operation of picene thin film field-effect transistor (FET) has been realized with 40 nm thick SiO(2) gate dielectrics coated by two polymers, Cytop (TM) and polystyrene. The picene FETs operated in low absolute gate voltage vertical bar V(G)vertical bar below 15 V for Cytop (TM) coated SiO(2) and 30 V for polystyrene coated SiO(2) gate dielectrics, and they showed a significant O(2) gas sensing effect down to similar to 10 ppm. Photoemission spectrum clarified that O(2) molecules penetrate into the thin films at O(2)/picene mole ratio of 1: 1. X-ray diffraction pattern of picene thin films showed highly oriented growth on the polymer-coated SiO(2).

DOI： 10.1063/1.3257373

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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：ELSEVIER SCIENCE BV  

C-60 and picene thin film field-effect transistors (FETs) in bottom contact structure have been fabricated with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PED-OT:PSS) electrodes for a realization of mechanical flexible organic FETs. The C-60 thin film FETs showed n-channel enhancement-type characteristics with the field-effect mobility mu value of 0.41 cm(2\) V-1 s(-1), while the picene thin film FET showed p-channel enhancement-type characteristics with the p of 0.61 cm(2) V-1 s(-1). The p values recorded for C-60 and picene thin film FETs are comparable to those for C-60 and picene thin film FETs with Au electrodes. (C) 2009 Elsevier B.V. All rights reserved.

DOI： 10.1016/j.orgel.2009.01.006

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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 INST PHYSICS  

Transport characteristics and trap states are investigated in picene thin film field-effect transistor under O(2) atmosphere on the basis of multiple shallow trap and release (MTR) model. The channel transport is dominated by MTR below 300 K. It has been clarified on the basis of MTR model that the O(2)-exposure induces a drastic reduction in shallow trap density to increase both the field-effect mobility mu and on-off ratio. We also found that the O(2)-exposure never caused an increase in hole carrier density. Actually, a very high mu value of 3.2 cm(2) V(-1) s(-1) is realized under 500 Torr of O(2).

DOI： 10.1063/1.3076124

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

This account provides an overview of the photochemical properties of cyclophanes possessing nitrogen atoms in the bridge chains, namely 2,11-diaza[32]anthracenoparacyclophane and 2,11-diaza[3 2]paracyclophane systems. Although the photoreactions of aromatic molecules that are bound by a linker or fixed in a cyclophane structure have been widely investigated, much less attention has been paid to the photochemistry of aromatic rings incorporated in a nitrogen-bridged cyclophane. During the course of our work on the photoreactions of cyclophanes possessing nitrogen atoms in their bridge chains, the nitrogen-bridged cyclophanes were found to display photoproperties significantly different from those of the nonbridged aromatic chromophores or the corresponding carbonbridged cyclophane analogues. The 2,11-diaza[32]anthracenoparacyclophane system displayed an efficient photochemical cycloaddition-adiabatic cycloreversion cycle in the excited singlet state, while in the triplet state, the photoisomer underwent a novel rearrangement and adiabatic cycloreversion. Upon photolysis of the 2,11-diaza[32]paracyclophane system, an octahedrane cage was formed. This is the first reported octahedrane formation to occur by the photochemical dimerization of benzene. Thus, the title cyclophane systems display a variety of photoprocesses involving cycloaddition, adiabatic cycloreversion accompanied by photoinduced chemiluminescence, novel rearrangements, and previously unknown benzene dimerization. 1 Introduction 2 Photochemistry of the 2,11-Diaza[32]anthracenoparacyclophane System 2.1 General Comments on the Photochemical Cycloaddition and Cycloreversion of Aromatic Molecules in the Singlet State 2.2 Intramolecular Photochemical Cycloaddition and Cycloreversion of the 2,11-Diaza[32] anthracenoparacyclophane System 2.3 General Introduction to the Photochemistry of Aromatic Molecules in the Triplet State 2.4 Photoproperties of the 2,11-Diaza[32]anthracenoparacyclo-phane System in the Triplet State 3 Photochemistry of the 2,11-Diaza[32]paracyclophane System 3.1 General Remarks on the Photoreactions of Cyclophanes Containing Two Benzene Rings 3.2 Construction of the 2,11-Diaza[32]paracyclophane Skeleton 3.3 Photoreactions of the 2,11-Diaza[32]paracyclophane System 4 Summary.

DOI： 10.1055/S-2008-1078574

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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  

A field-effect transistor (FET) with thin films of picene has been fabricated on SiO(2) gate dielectric. The FET showed p-channel enhancement-type FET characteristics with the field-effect mobility, mu, of 1.1 cm(2) V(-1) s(-1) and the on-off ratio of >10(5). This excellent device performance was realized under atmospheric conditions. The p increased with an increase in temperature, and the FET performance was improved by exposure to air or O(2) for a long time. This result implies that this device is an air (O(2))-assisted FET. The FET characteristics are discussed on the basis of structural topography and the energy diagram of picene thin films.

DOI： 10.1021/ja803291a

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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 title trifluoroacetylaminophthalimide derivative produced a violet fluorescence (lambda(FL)(max) 392 nm) in MeCN, and it displayed a green emission (lambda(FL)(max) 506 nm) after irradiation at 254 nm in the presence of iodide ions. The corresponding amidate ion of the trifluoroacetamide was identified as the green fluorescence emitter. The deprotonation reaction may be caused by proton-abstracting solvated electrons generated by a photochemical charge-transfer-to-solvent process from I(-) to MeCN.

DOI： 10.1021/ol801184x

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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：GEORG THIEME VERLAG KG  

The diaza[3(2)]cyclophane skeleton has been constructed by the bis-N-alkylation of 1,4-bis[(4-nitrophenylsulfonylamin o)methyl] benzene with 1,4-bis(halomethyl)benzene in the presence of sodium hydride. The 4-nitrophenylsulfonyl (Ns) amides in the bridge chains of the cyclophane were effectively deprotected by sodium ethanethiolate and the resulting free amine moieties were reprotected as the trifluoroacetamide under mild conditions to afford 3,7-bis(trifluoroacetyl)-3,7-diaza-1,5(1,4)-dibenzenacyclooctaphane in 26% overall yield. This Ns-amide method has also been applied for the preparation of a higher homologue, the trifluoroacetamide derivative of triaza[3(3)]cyclophane, 3,5,7-tris(trifluoroacetyl)-3,7, 10-triaza- 1,5(1,3,5)-dibenzenabicyclo[3.3.3]undecaphane, in 18% overall yield. Thus, the present procedure provides a convenient synthetic route to azacyclophane derivatives possessing trifluoroacetamide groups in the bridge chains.

DOI： 10.1055/s-2007-1000825

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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：ARKAT USA INC  

The effects of solvents and metal cations on the fluorescence spectra of 3- ( 1) and 4- ( 2) trifluoroacetylamino-1,8-naphthalimides were investigated. In MeCN, these naphthalimides displayed a violet similar to blue fluorescence based on their neutral amide form ( 1, 2). Whereas in DMSO, they gave off a yellow similar to orange emission due to their amide anions (1(-), 2(-)). In MeOH, naphthalimide 2 emitted a dual fluorescence (lambda(FL) 436 and 556 nm) to display a white luminescence. Naphthalimides 1, 2 are essentially insensitive to metal cations in their neutral amide form. In contrast, the fluorescence of the amide anions 1-, 2- was quenched by metal cations. The efficiency of the quenching correlated with the Lewis acidity of the metal cations; a stronger Lewis acid tended to display a more effective fluorescence quenching. Therefore, the fluorescence color and the sensitivity to metal cations of the naphthalimides were effectively switched by the solvent.

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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  

DOI： 10.1021/ja067350r

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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  

Although heating 2-methoxy-2H-azepine results in a [1,5] sigmatropic hydrogen shift, heating 2-propylthio-2H-azepine results in not only a [1,5] sigmatropic hydrogen shift but also a [1,5] sigmatropic propylthio shift. Kinetic measurements reveal that migratory aptitudes increase in the order of MeO < H, PrS. These [1,5] sigmatropic shifts are discussed on the basis of ab initio DFT calculations.

DOI： 10.1021/ol062131w

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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：BLACKWELL PUBLISHING  

The accurate X-ray single-crystal structures of the isoflavone compounds 4-O-methylalpinumisoflavone, O, O-dimethylalpinumisoflavone and 5-O-methyl-4-O-( 3-methylbut-2-en-1-yl) alpinumisoflavone {alpinumisoflavone = 5-hydroxy7-( 4-hydroxyphenyl)-2,2-dimethyl-2H, 6H-benzo[ 1,2-b: 5,4-b']dipyran-6-one} from data sets measured at cryogenic temperature have been obtained from invariom modelling using theoretically predicted Hansen and Coppens multipole-model form factors, which describe the aspherical electron density distribution. Molecular dipole moments and electrostatic potentials obtained from invariom modelling are discussed and compared with results from ab initio theoretical calculations. All three studied compounds are solvent extracts of root bark or seed powder of Millettia thonningii ( leguminosae), a plant molluscicide and cercaricide used in Franco West Africa as medication against various diseases. The compounds' toxicities to brine shrimp have been determined and their different potencies tentatively related to conformation differences, intramolecular contacts, dipole moments and electrostatic potential features.

DOI： 10.1107/S0108768106019616

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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  

2-Aryl-2H-, 3-aryl-3H-, and 4-aryl-4H-azepine were formed by the novel, electrophilic, pi(LUMO)-controlled reaction of the 2-methoxyazepinium ion, generated in situ by the reaction of TiCl4 with 2,7-dialkoxy-2H-azepine and an aryl compound, for which the kinetic parameters of the sigmatropic hydrogen rearrangement of the 4H-azepine was measured. The substitution and hydrogen shift of the azepinium ion were analyzed with DFT studies. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006).

DOI： 10.1002/ejoc.200600257

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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/crat.200510656

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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  

The novel azacrowned phthalimide 1 has been prepared and its fluorescence properties have been investigated by addition of EtOH and Ag+. The phthalimide 1 showed appreciable solvatofluorochromism; its fluorescence maxima (lambda(FL)) appeared in the wavelength region between 458 (in Et2O) and 544 nm (in EtOH). In benzene, the phthalimide 1 gave off blue emission (lambda(FL) 466 nm) while it emitted green fluorescence (lambda(FL) 497 nm) upon addition of 250 mM of EtOH. Both the blue and the green emissions were quenched by Ag+. Potential logic operations of the phthalimide 1 were examined using fluorescence outputs at 450 (Out(1)) and 515 nm (Out(2)) and two input stimuli, EtOH (In,) and Ag+ (In-2). The Out, was on in the absence of these inputs while its intensity was reduced (off) by either or both of the inputs to serve as a NOR operator. The Out(2) was off without the inputs; in contrast, the intensity of Out(2) was enhanced (on) by In-2. The enhanced Out(2) was switched off by In-2. The Obt(2), thus, corresponds to an INHIBIT operation responding to the input signals. The crowned phthalimide 1 mimics a two-input-two-output combinational logic gate with a single fluorophore and a single ion-sensing unit.

DOI： 10.1246/bcsj.78.2180

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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  

Although the reactivity of tropylium ion with aromatic substrates is low, the reaction of azepinium ion with aromatic substrates such as benzene, phenol, furan, and thiophene resulted in the formation of 2-aryl-2H-azepine as a major product. An exceptional result in the formation of ring-contracted product was observed in the reaction with pyrrole.

DOI： 10.1021/ol052049l

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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  

The novel azacrowned isoluminol has been prepared as the first luminol analogue possessing an azacrown ionophore. The crowned isoluminol displayed flash chemiluminescence upon addition of alkali-metal iodides in acetonitrile containing alkaline hydrogen peroxide and the chemiluminescence intensity varied depending on the metal cations studied; K+ >> Na+ > Li+.

DOI： 10.1246/cl.2005.1452

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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 reaction of 2-methoxy-3H-azepines, in the presence or absence of a nucleophile, with N-bromosuccinimide (NBS) gave a regioselective 1,4-adduct from which the corresponding 2H-azepine derivatives were formed via base-promoted hydrogen bromide elimination, generally in moderate to quantitative yield. Competitive formation of 4-bromo-2-methoxy-3H-azepine by electrophilic substitutuion or 3H-azepin-2-yl 2H-azepin-2-yl ether by transetherification was minimized at lower reaction temperatures. Quantitative substitution of 2-(2',4',6'-trichlorophenoxy)2H-azepine derivatives, formed in moderate yield from the respective 3H-azepine and NBS in the presence of 2,4,6-trichlorophenol (TCP), by various nucleophiles gave the corresponding 2-substituted 2H-azepine. Among these nucleophiles were alkanethiol and alkylamine that are not tolerated in the reaction of 3H-azepine and NBS.

DOI： 10.1021/jo0500232

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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 triplet-sensitized photoreactions of the title biplanophane system 6, the photoisomer of a 2,11diaza[3,31(9,10)anthracenoparacyclophane derivative 5, were investigated by stationary and laserflash photolyses using xanthone (XT) and benzophenone (BP) as triplet sensitizers. Vaen photoisomer 6 underwent XT-sensitized irradiation, a triplet cyclophane 5 and a novel polycyclic product 7 were obtained via an adiabatic cycloreversion and a formal [2pia + 2 pia + 2sigmas] rearrangement, respectively. The maximum quantum yield for the formation of cyclophane 5 (0.69) and the upper-limit efficiency for the formation of polycycle 7 (0.31) were determined by laser photolysis techniques. For BP-sensitized photolysis of photoisomer 6, oxetane 8, in addition to triplet cyclophane 5 and polycycle 7, was formed by a Paterno-Biichi reaction. The quenching rate constant (k(q)) of triplet BP by photoisomer 6 (3.4 x 10(8) dm(3) Mol(-1) s(-1)) was found to be 1 order of magnitude smaller than that for XT (5.0 x 10(9) dm(3) mol(-1) s(-1)). On the basis of the relationship between k(q) and the triplet donor-acceptor energy gap, the triplet energy level of photoisomer 6 was estimated to be similar to71 kcal mol(-1). The photochemical and the photophysical processes involved in the sensitized photolyses are summarized in an energetic reaction diagram and discussed in detail.

DOI： 10.1021/jo048757m

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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  

DOI： 10.1002/anie.200352794

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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  

The reaction of 5-tert-butyl-2-methoxy-3H-azepine (2a) with sodium alkoxides gave 2-alkoxy-3H-azepine derivatives 3-6 by nucleophilic transetherification. The treatment of 2a with tert-butyllithium also yielded 2,5-di-tert-butyl-3H-azepine (7): however, the reaction of 2a and methyllithium gave the expected 5-tert-butyl-2-methyl-3H-azepine (8) along with unexpected 5-tert-butyl-2,2-dimethyl-2,3-dihydro-1H-azepine (9). but also 5,5'-di(tert-butyl)-2,2'-methylenedi(3H-azepine) (11), the structure of which was found to be tautomerized 5-tert-butyl-2-(5-tert-butyl-2,3-dihydro-1H-azepine-2-ylidenemethyl)-3H-azepine (12). The energy profile for the observed tautomerization is discussed based on ab initio DFT calculations and kinetic measurements.

DOI： 10.1246/bcsj.76.805

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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  

UVA-irradiation of the photo-Fenton reagents N-isopropoxypyridone 2b and N-isopropoxythiazole-2(3H)-thione 3b releases radicals which induce strand breaks. Transient spectroscopy establishes N-O bond scission [Phi(N-O) = (75 8)% for 2b and (65 7)% 3b] as the dominating primary photochemical process to afford the DNA-damaging radicals. Product studies and laser-flash experiments reveal that the thiazolethione 3b leads primarily to the disulfide 5, from which through C-S bond breakage, the bithiazyl 6, the thiazole 7, and the isothiocyanate 8 are derived. Upon irradiation of pyridone 2b (300 nm) in aqueous media, a mixture of isopropoxyl and 2-hydroxyprop-2-yl radicals is formed, as confirmed by trapping with 5,5-dimethyl-1-pyrroline N-oxide (DMPO) and EPR spectroscopy. In contrast, the photolysis of the thiazolethione 3b (350 nm) affords exclusively the DMPO adducts of the isopropoxyl radicals. Control experiments disclose that the thiazolethione-derived photoproduct disulfide 5, or the intermediary thiyl radicals B, scavenge the carbon-centered 2-hydroxyprop-2-yl radicals, which are generated from the isopropoxyl radicals by hydrogen shift. With supercoiled pBR 322 DNA in a 60:40 mixture of H2O-MeCN, the pyridone 2b and the thiazolethione 3b display moderate strand-break activity (17% open-circular DNA for 2b and 12% for 3b). In pure water, however, the pyridone 2b photoinduces substantially more DNA cleavage (32% open-circular DNA), which is attributed to the peroxyl radicals generated from the 2-hydroxyprop-2-yl radicals by oxygen trapping. The lower strand-break activity of the thiazolethione 3b derives presumably from isopropoxyl radicals, because only these are detected in the photolysis of this photo-Fenton reagent.

DOI： 10.1021/jo025856w

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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：PERGAMON-ELSEVIER SCIENCE LTD  

Reaction of 5-t-butyl-2-methoxy-3H-azepine (2) with nuclephiles (alkoxides or t-butyllithium) gave respective substitution product at 2-position of the ring. Unexpectedly, when methyllithium was used as a nucleophile, bis(5-t-butyl-3H-azepin-2-yl)methane (7), the structure of which found to be tautomeric vinamidine (7a,b), was formed. Tautomerization between 7 and 7a,b was characterized spectroscopically and theoretically based on the levels of B3LYP/631G(d).

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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：PERGAMON-ELSEVIER SCIENCE LTD  

A guest-sensitive chemiluminophore, a novel crown-ether-modified lophine peroxide 1. has been prepared. and its chemiluminescent behavior has been investigated in the presence of alkaline and alkaline earth metal cations. In the presence of Na+, the lambda (max) of the chemiluminescence of peroxide 1 was blue-shifted (505 nm) compared to the case without a metal cation (566 nm). The chemiluminescent intensity was enhanced by addition of Na+ while that of Mg2+ decreased the intensity. (C) 2001 Elsevier Science Ltd. All rights reserved.

DOI： 10.1016/S0040-4039(01)01572-6

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1562/0031-8655(2000)072<0619:NHCTHT>2.0.CO;2

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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  

The conformation of 2,11-diaza[3.3](9,10)anthracenoparacyclophane 1, which underwent photointerconversion with isomer 2, was fixed with the aid of a chiral camphanic auxiliary to have molecular chirality, and the photochemiluminescence from the modified 2a was circularly polarized reflecting the chirality of the emitting state.

DOI： 10.1039/a801296b

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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 Society of Japan  

The efficiency for excited product formation in the adiabatic photocycloreversion of bridged biplanemer 1 was controlled by the size of its side-chain substituents which changed the interchromophore distance in the photoproduct 2.

DOI： 10.1246/cl.1997.873

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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 Society of Japan  

A reaction of electrophilic bromination of norbornadiene homologs such as bicyclo[2.2.2]octa-2,5-diene (4) and bicyclo[3.2.2]nona-6,8-diene (7) with bromine gave hitherto unknown skeleton rearranged dibromides. The rearrangement may proceed via a bromonium cation of starting diene to give bicyclo[3.2.1]octene or bicyclo[3.3.1]nonene skeleton in respective cases. The observed rearrangement reactions are also confirmed in 6,7-bis(methoxycarbonyl) derivatives of bicyclodiene 7 under similar conditions.

DOI： 10.1246/bcsj.69.453

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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 Society of Japan  

A new ring contraction reaction giving pyridine derivatives from 3,6-and 2,5-di-tert-butyl-3H-azepines was observed by a successive treatment with bromine and aqueous K2CD3. A plausible mechanism via azatropilium cation for the rearrangement was discussed based on the product's distribution from respective 3H-azepines.

DOI： 10.1246/cl.1996.1129

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

9,10-difluorotetracyclo[6.4.21,8.29,12.02,7]hexadeca-2,4,6,10,13,15-hexaene-3, 6-dione is thermally labile and shows a notably clear, long wave-length CT absorption. © 1992.

DOI： 10.1016/S0040-4039(00)60910-3

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Demethoxycarbonylation of methyl 2,5,-di-tert-butyl-1H-azepine-1- carboxylate using 1,8-diazabicyclo[5.4.0]undec-7-ene gives exclusively two isomers of 3H-azepine derivatives, while methyl 3,6-di-tert-butyl-1H-azepine-1- carboxylate gives a mixture of 2H-, 3H- and 4H-azepine derivatives under the same conditions because of a 1,5-hydrogen shift in the resulting triene system.

DOI： 10.1039/C39910001154

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Electronic oxidative bisdecarboxylation of photoadducts of 2,5-dihalo-1,2-dihydrophthalic anhydride and anthracene gave the corresponding energy-rich heterodimers 12 and 13. The quantum yields of the formation of the excited anthracene from 12 and 13 by the irradiation of 280-nm light were 0.65 and 0.25, respectively. We assumed that the heterodimers of 12 and 13 form biradicaloid intermediates during thermal retro [4πs + 4πs] cycloaddition and consumed their stored energy without any visible light. However, we observed emission light from 340 to 460 nm through a glass filter and the formation of anthracene using Nd-YAG laser IR light (1.06 μm) by the multiphoton absorption, when fine powders of 12 and 13 were used. © 1988, American Chemical Society. All rights reserved.

DOI： 10.1021/jo00252a004

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

9,12-Difluoro-and 9,12-dichlorotetracyclo[6.4.2.2&lt
sup&gt
9.12&lt
/sup&gt
.0&lt
sup&gt
2.7&lt
/sup&gt
] hexadeca-2,4,6,13,15-pentaene-10,11 -dicarboxylic anhydrides (2a) and (2b) were prepared by 4π&lt
inf&gt
s&lt
/inf&gt
+ 4π&lt
inf&gt
s&lt
/inf&gt
is photocycloaddition between cis-3,6-difluoro-or cis-3,6-dichloro-1,2-dihydrophthalic anhydride and naphthalene, respectively. 12, 15-Difluoro-and 12, 15-dichlorohexacyclo [8.6.0.0&lt
sup&gt
2.15&lt
/sup&gt
.0&lt
sup&gt
3.8&lt
/sup&gt
.0&lt
sup&gt
9.12&lt
/sup&gt
.0&lt
sup&gt
11.16&lt
/sup&gt
] hexadeca-3,5,7-triene-13,14-dicar-boxylic anhydrides (6a) and (6b) were obtained by 2π&lt
inf&gt
s&lt
/inf&gt
+ 2π&lt
inf&gt
s&lt
/inf&gt
is intramolecular photocycloaddition of adducts (2a) and (2b), respectively. 12,15-Difluorohexacyclo[8.6.0.0&lt
sup&gt
2.15&lt
/sup&gt
.0&lt
sup&gt
3.8&lt
/sup&gt
.0&lt
sup&gt
9.12&lt
/sup&gt
.0&lt
sup&gt
11.16&lt
/sup&gt
]hexadeca-3,5,7,13-tetraene (7a) has been synthesized by the electro-oxidative decarboxylation of anhydride (6a) and the excited singlet naphthalene has been observed on irradiation of adduct (7a), and is presumably formed via an adiabatic pathway. © 1988, The Royal Society of Chemistry.

DOI： 10.1039/P19880003307

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DOI： 10.1021/ol801184x

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記述言語：英語   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

DOI： 10.1142/9789812702203_0043

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DOI： 10.1142/9789812702203_0043

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