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151.
Takumi Mizuno Manabu Matsumoto Ikuzo Nishiguchi Tsuneaki Hirashima 《Heteroatom Chemistry》1993,4(5):455-458
Urea derivatives were readily synthesized in good yields under quite mild conditions, i.e., at ambient pressure and room temperature by sulfur-assisted carbonylation of primary amines with carbon monoxide followed by oxidation of the resulting ammonium thiocarbamates with molecular oxygen. 相似文献
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Takumi Mizuno Noriaki Okamoto Takatoshi Ito Toshiyuki Miyata 《Heteroatom Chemistry》2000,11(6):428-433
Sulfur‐assisted carbonylation of 2‐aminobenzonitriles with carbon monoxide using K2CO3 as a base under ambient conditions (1 atm, 20°C) to afford 2‐hydroxy‐4‐mercaptoquinazolines in excellent yields was found. This carbonylation was applied to chemical fixation of carbon dioxide under mild conditions. Carbon dioxide (1 atm) easily reacted with 2‐aminobenzonitriles at 20°C assisted by 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) to give 2,4‐dihydroxyquinazolines in excellent yields. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:428–433, 2000 相似文献
155.
Tsuyoshi Honma Rie Ihara Yasuhiko Benino Ryuji Sato Takumi Fujiwara Takayuki Komatsu 《Journal of Non》2008,354(2-9):468-471
We examined the laser-induced crystallization to form the fresnoite type Ba2TiGe2O8 crystal line patterns in transition metal ion doped BaO–TiO2–GeO2 glass. Ba2TiGe2O8 crystal line was written in 0.6FeO–33.3BaO–16.7TiO2–50GeO2 glass by continuous wave yttrium–aluminum–garnet (YAG) laser irradiation. We obtained polarization dependence of Raman spectra in crystal line pattern. Second harmonic generation (SHG) indicated unique fringe patterns from Ba2TiGe2O8 crystal lines. 相似文献
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Furuta T Sakai M Hayashi H Asakawa T Kataoka F Fujii S Suzuki T Suzuki Y Tanaka K Fishkin N Nakanishi K 《Chemical communications (Cambridge, England)》2005,(36):4575-4577
An artificial phospholipid, possessing saturated alkyl chains as a membrane anchor and protein recognition site as well as an Fe(III)-EDTA moiety as a protein cleavable polar head group, was designed and synthesized based on the amidite method for the purpose of examination of cleavage of integral membrane proteins. 相似文献
160.
Konno T Haneishi K Hirotsu M Yamaguchi T Ito T Yoshimura T 《Journal of the American Chemical Society》2003,125(31):9244-9245
Treatment of fac(S)-[Rh(aet)3] (aet = 2-aminoethanethiolate) with aqueous HBF4 in air led to the protonation at coordinated thiolato groups to give a rhodium(III) dimer, [{Rh(aet)2(Haet)}{Rh(aet)(Haet)2}](BF4)3 ([1](BF4)3). On the other hand, similar treatment of fac(Se)-[Rh(aes)3] (aes = 2-aminoethaneselenolate) produced a dinuclear rhodium(III) complex, [Rh2(selenocystamine)3](BF4)6 ([2](BF4)6), because of the autoxidation of coordinated selenolato groups by air. The crystal structures of [1](BF4)3, DeltaDelta-[1](BF4)3, and [2](BF4)6 were determined by X-ray crystallography. In [1]3+ two RhIII octahedrons are connected through a strong triple thiol-thiolate S-H...S hydrogen bond, while two RhIII octahedrons are directly joined by a triple diselenide bond in [2]6+. The cyclic voltammetry indicated that in acidic media the RhIII center in fac(Se)-[Rh(aes)3] is more easily oxidized to RhIV than that in fac(S)-[Rh(aet)3], which is responsible for the formation of coordinated diselenide bonds. 相似文献