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31.
K. Hirose M. Ejima T. Fujibayashi Y. Fujii K. Futatsukawa O. Hashimoto T. Ishikawa S. Kameoka H. Kanda F. Kato S. Kinoshita T. Kinoshita T. Kon O. Konno K. Maeda A. Matsumura Y. Miura F. Miyahara H. Miyase T. Nakabayashi S.N. Nakamura H. Nomura K. Nonaka A. Ohtani Y. Okayasu M. Oyamada A. Sasaki H. Shimizu T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada D. Uchida M. Ukai M. Wakamatsu T. Watanabe H. Yamauchi H. Yamazaki K. Yawata 《Physics letters. [Part B]》2009
32.
Makoto Watanabe Masanori Morita Makoto Sakurai Mioko Maeda 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1823-1826
Preparations of small-ring and short-chain condensed phosphates were made by dry and wet processes, respectively. The crystallization of tetra- hexa-, and octaphosphates from the phosphate solution was not easy, and metal salts of these oligophosphates were amorphous and unstable at normal temperature. Guanidine tetraphosphate and ammonium hexaphosphate were crystalline and stable at normal temperature. 相似文献
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Makoto Uchimura Ryohei Ishige Masayuki Shigeta Yuki Arakawa Yosuke Niko Junji Watanabe Gen-Ichi Konishi 《Research on Chemical Intermediates》2013,39(1):403-414
We synthesized thermotropic liquid-crystalline polyesters in which 9,10-diphenylanthracene moieties are incorporated into the main chain type of polyester forming the chiral smectic C (Sm C*). The polymers were prepared by the isopropyltitanate-catalyzed reaction of biphenyldicarboxylic acid and the corresponding diols, with different ratios of diol of 9,10-diphenylanthracene moiety to the alkane diols (1, 5, and 10 mol %) under nitrogen atmosphere. The polymers exhibited thermotropic liquid crystals despite the presence of a bulky diphenylanthracene moiety in the main chain. The circular dichroism spectra revealed that a Sm C* phase was formed in the polymer with 1 mol % of anthracene moiety, although only an Sm A phase was formed in the other polymers. This is the first example of a Sm C* polyester containing a diphenylanthracene moiety in the main chain. Furthermore, we measured the optical properties of the polymers and found that they exhibited very high fluorescent efficiency. The fluorescence spectra of the thin film differed from that of a CH2Cl2 solution. 相似文献
36.
Minami Odagi Kota Furukori Tatsuya Watanabe Prof. Dr. Kazuo Nagasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(49):16740-16745
Highly enantioselective catalytic oxidation of 1‐tetralone‐derived β‐keto esters was achieved by using a guanidine–urea bifunctional organocatalyst in the presence of cumene hydroperoxide (CHP), a safe, commercially available oxidant. The α‐hydroxylation products were obtained in 99 % yield with up to 95 % enantiomeric excess (ee). The present oxidation was successfully applied to synthesize a key intermediate of the anti‐cancer agent daunorubicin ( 2 ). 相似文献
37.
Direct Synthesis of 1,4‐Diols from Alkenes by Iron‐Catalyzed Aerobic Hydration and C?H Hydroxylation
Takuma Hashimoto Daisuke Hirose Tsuyoshi Taniguchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(10):2768-2772
Various 1,4‐diols are easily accessible from alkenes through iron‐catalyzed aerobic hydration. The reaction system consists of a user‐friendly iron phthalocyanine complex, sodium borohydride, and molecular oxygen. Furthermore, the effect of additional ligands on the iron complex was examined for a model reaction. The second hydroxy group is installed by direct C(sp3) H oxygenation, which is based on a [1,5] hydrogen shift process of a transient alkoxy radical that is formed by formal hydration of the olefin. 相似文献
38.
Krüger A. L Nicolodelli G Villas-Boas P. R Watanabe A Milori D. M. B. P 《Plasma Chemistry and Plasma Processing》2020,40(6):1417-1427
Plasma Chemistry and Plasma Processing - Laser-induced breakdown spectroscopy (LIBS) has been considered a promising tool for agricultural analysis in the recent years due to its advantages over... 相似文献
39.
Mami Miyairi Tsuyoshi Taniguchi Tatsuya Nishimura Katsuhiro Maeda 《Angewandte Chemie (International ed. in English)》2020,59(35):14772-14780
An alternative reaction mechanism of the polymerization of diphenylacetylelnes using a catalytic system composed of tungsten(VI) chloride and tetraphenyltin has been proposed through the optimization of reaction conditions and investigation of the effect of the electronic nature of diphenylacetylene monomers on the polymerizability. The detailed structures of the polymers have been suggested by mass spectrometric analysis of the obtained polymers and oligomers, which suggested that a phenyl group of tetraphenyltin has been introduced to an initiating end of the polymer chain. Mass spectrometric analysis also provided information about the termination processes of the polymerization. The experimental results strongly suggested that the polymerization of diphenylacetylenes using tungsten(VI) chloride and tetraphenyltin proceeds through a migratory insertion mechanism rather than the long‐accepted metathesis mechanism. 相似文献
40.
Sodium cyclo-octaphosphate heptahydrate, (NaPO3)8 · 7H2O, has been made by heating lead cyclo-tetraphosphate at 340°C, dissolving the thermal product in a 3% aqueous solution of tetrasodium ethylene-diaminetetraacetate, and then crystallizing it by addition of sodium chloride and acetone to the solution. When the cyclo-octaphosphate was heated up to 400°C, it decomposed to produce phosphates with both shorter and longer chain lengths. A main product at 300° to 350°C was sodium cyclo-triphosphate, and the thermal product melted at about 630°C. 相似文献