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84.
Shigeru Sasaki Kohji Sasaki Mariko Watanabe Kazunobu Ogawa Noboru Morita Masaaki Yoshifuji 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):256-261
Abstract Synthesis, redox properties, and electronic spectra of the sterically crowded triarylphosphines conjugated with π-electron systems, especially electron acceptors such as carbonyl group, are briefly reviewed. The sterically crowded triarylphosphines conjugated with various π-electron systems were synthesized from the common synthetic intermediate, (bromoaryl)phosphine, by conventional manner. The sterically crowded triarylphosphines conjugated with the electron acceptors exhibit visible absorption and fluorescence with large Stokes shift. Large solvent effect, redshift in polar solvent, and good correlation with the difference of the oxidation potential of the phosphine moiety and the reduction potential of the acceptor moiety suggest polar excited state resulting from HOMO-LUMO transition. 相似文献
85.
Shigeru Oae Kazuyuki Iida Toshikazu Takata 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):103-113
Abstract Reduction of sulfimides and sulfoximides with p-toluenesulfonyl nitrite, a new nitrosating agent, gave nearly quantitatively the corresponding deimination products, sulfides and sulfoxides, respectively. In the reaction of dialkyl and aryl alkyl sulfoximides with t-butyl thionitrate, N-t-butylthiosulfoximides were obtained besides the usual deimination products, although diaryl sulfoximides were readily deiminated to the corresponding sulfoxides in good yields in the same treatment. t-Butyl thionitrate was also found to deiminate diphenyl sulfimide to give diphenyl sulfide in good yield. Sulfoximides reacted sluggishly with t-butyl thionitrite, however, eventually affording a small amount of sulfoxides. 相似文献
86.
Naomichi Furukawa Mitsuo Fukumura Takehiko Nishio Shigeru Oae 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):231-237
Abstract Various N-acyldiphenylsulfilimines (1a-k) were found to undergo photolysis in argon atmosphere, to afford the corresponding isocyanates, diphenyl sulfide and diphenyl disulfide. Attempts to trap intramolecularly the acylnitrene with olefinic linkage or sulfide afforded small amounts of the trapped products, whereas photolysis of N-mesitoyldiphenyl-sulfilimine (Ia) afforded a C–H inserted product of the nitrene in a substantial yield together with the isocyanate. Benzophenone-sensitized photolysis of Ia indicates that the nitrene generated is a singlet species. 相似文献
87.
Norimasa Yoza Hisanobu Hirano Yoshinobu Baba Shigeru Ohashi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):605-608
Abstract Inorganic pyrophosphatase (EC 3. 6. 1. 1) drived the reaction of uridine 5′-triphosphate with glucose 1-monophosphate in the direction of uridine 5′-diphosphoglucose formation. 相似文献
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89.
Idris Zembouai Mustapha Kaci Stéphane Bruzaud Aida Benhamida Yves-Marie Corre Yves Grohens 《Polymer Testing》2013,32(5):842-851
The paper aims to study blend properties of biodegradable polymers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polylactide (PLA) prepared by melt mixing. Blend compositions based on PHBV/PLA were investigated according to the following weight ratios, i.e. 100/0, 75/25, 50/50, 25/75 and 0/100 wt%. The study showed through scanning electron microscopy (SEM) that blends of PHBV/PLA are not miscible. This is consistent with differential scanning calorimetry (DSC) data which indicate the presence of two distinct glass transition temperatures (Tg) and melting temperatures (Tm), attributed to the neat polymers, over all the range of blend compositions. Water and oxygen barrier properties of PHBV/PLA blends are significantly improved with increasing the PHBV content in the blend. Further, morphological analyzes indicated that increasing the PHBV content in the polymer blends results in increasing the PLA crystallinity due to the finely dispersed PHBV crystals acting as a filler and a nucleating agent for PLA. On the other hand, the addition of PLA to the blend results in a very impressive increase in the complex viscosity of PHBV. Moreover, the rheological data showed that, excluding the specific behavior of the neat polymers at low frequencies, i.e. less than 0.1 Hz, the complex viscosity of PHBV/PLA blends fits the mixing law well. 相似文献
90.
Tao Yang Prof. Dr. Xiang Zhao Prof. Dr. Shigeru Nagase 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2649-2654
Like C60, C70 is one of the most representative fullerenes in fullerene science. Even though there are 8149 C70 isomers, only two of them have been found before: the conventional D5h and an isolated pentagon rule (IPR)‐violating C2v(7854). Through the use of quantum chemical methods, we report a new unconventional C70 isomer, C2(7892), which survives in the form of dimetallic sulfide endohedral fullerene Sc2S@C70. Compared with the IPR‐obeying C70 and the C2v(7854) fullerene with three pairs of pentagon adjacencies, the C2(7892) cage violates the isolated pentagon rule and has two pairs of pentagon adjacencies. In Sc2S@C2(7892)‐C70, two scandium atoms coordinate with two pentalene motifs, respectively, presenting two equivalent Sc? S bonds. The strong coordination interaction, along with the electron transfer from the Sc2S cluster to the fullerene cage, results in the stabilization of the non‐IPR endohedral fullerene. The electronic structure of Sc2S@C70 can be formally described as [Sc2S]4+@[C70]4?; however, a substantial overlap between the metallic orbitals and cage orbitals has also been found. Electrochemical properties and electronic absorption, infrared, and 13C NMR spectra of Sc2S@C70 have been calculated theoretically. 相似文献