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Yukio Terashima Kiyoshi Takeda Makoto Honda 《The Journal of chemical thermodynamics》2011,43(3):307-310
The phase and glass transition behaviour in a binary mixture of sodium perchlorate and 1,2-propanediamine {(NaClO4)x(12PDA)1?x, x < 0.40} was investigated by differential scanning calorimetry and Raman scattering measurements. A eutectic point and a peritectic point were found at x = 0.17 and 0.19, respectively. The phase diagram indicates the existence of solvated compounds of (NaClO4)1(12PDA)4 and (NaClO4)2(12PDA)5. The concentration dependence of the glass transition point shows a sigmoid curve implying an underlying anomaly. 相似文献
108.
Mami Fujii Takashi Nishiyama Tominari Choshi Nanase Satsuki Takaya Fujiwaki Takumi Abe Minoru Ishikura Satoshi Hibino 《Tetrahedron》2014
A novel one-pot synthesis of carbazole-1,4-quinone by consecutive Pd-catalyzed cyclocarbonylation, desilylation, and oxidation reactions is described. We propose a possible mechanism of the cyclocarbonylation reaction between 3-iodo-2-propenylindole and CO (1 atm) in the presence of a tributyl(vinyl)tin and Pd-catalyst and the resulting acylpalladium species was directly coupled with a terminal alkene to produce the carbazole-1,4-quinone. To our knowledge, this is the first example of this type of reaction. A new formal total synthesis of a carbazole-1,4-quinone alkaloid, murrayaquinone A was established using this reaction. 相似文献
109.
Rh-catalyzed direct carboxylation of unactivated aryl C-H bond under atmospheric pressure of carbon dioxide was realized via chelation-assisted C-H activation for the first time. Variously substituted and functionalized 2-arylpyridines and 1-arylpyrazoles underwent the carboxylation in the presence of the rhodium catalyst and a stoichiometric methylating reagent, AlMe(2)(OMe), to give carboxylated products in good yields. The catalysis is proposed to consist of methylrhodium(I) species as the key intermediate, which undergoes C-H activation to afford rhodium(III), followed by reductive elimination of methane to give nucleophilic arylrhodium(I). This approach demonstrates promising application of C-H bond activation strategy in the field of carbon dioxide fixation. 相似文献
110.
K. Enomoto T. Yamaguchi T. Yakabe T. Terashima T. Konoike M. Nishimura S. Uji 《Physica E: Low-dimensional Systems and Nanostructures》2005,29(3-4):584
We report resistance measurements on a mesoscopic Al disk whose size is comparable to the superconducting coherence length. As the magnetic field increases, resistance peaks successively appear and some of the peak resistances are larger than the normal state value RN. These peaks are ascribed to the transitions between different vortex states in the superconducting Al disk. The experimental results suggest that some anomalous energy dissipation is caused by the dynamics of the vortices in the confined geometry. 相似文献