By treatment of (4R)-carboxy-(2S)-phenylthiazolidine(Ⅱ) with isocyanic acid benzyl ester in CH_3COOH/(CH_3CO)_2O system,the reaction time is shortened from 17 h to 3 h,and the yield of (7aR)-3-phenyl-1H,3H-imidazo[1,5-c] thiazole-(6H, 7aH) 5,7-dione(Ⅲ) is raised from 75% to 93%.
改用异氰酸苄酯为关环试剂环化合成了(7aR) 3 苯基 6 苄基 1H,3H 咪唑并[1,5 c]噻唑 5,7 二酮(Ⅲ),选用CH3COOH/(CH3CO)2O代替CH3COOH作溶剂,反应时间由17h缩短为3h,产率从75%提高到93%。
A DFT study of cyanic acid and isocyanic acid in the isomerization;
氰酸和异氰酸异构化反应的量子化学计算研究
The reaction path of isocyanic acid (HNCO) with carbon-hydrogen radicals CH, CH 2 and CH 3 have been investigated by using UMP2 method at 6-311g(d, p) level.
在UMP2 (FULL) / 6 311(d ,p)计算水平上 ,计算并讨论了碳氢自由基 (CHx)和异氰酸 (HNCO)发生氢转移反应位能面上驻点的结构和分子结构变化 ,并依据UMP2的优化构型 ,进一步采用UQCISD(T)方法对反应途径上的驻点进行了单点能量计算 。
The cycloaddition reactions of thioketene and isocyanic acid forming four-membered ring products were studied by means of ab initio RHF/6-31G* method.
采用从头算RHF/6-31G方法研究了硫代双烯酮与异氰酸之间两种可能的环加成反应的机理,并对反应各驻点进行了电子密度拓扑分析研究。
Determination of Toluene Diisocyanate(TDI)Trimer Content in Polyisocyanate Curing Agent by Partial Least Square Method;
偏最小二乘法测定多异氰酸酯固化剂中TDI三聚体的含量
Preparation and properties of tolylene diisocyanate cross-linked cationic acrylate resin;
甲苯二异氰酸酯交联阳离子型丙烯酸酯树脂的制备及性能
The role of styrene in isocyanate functionalization of ethylene-propylene copolymer;
苯乙烯在异氰酸酯官能化二元乙丙橡胶中的作用
Progress in the production of organic isocyanates;
有机异氰酸酯生产技术进展
Production and consumptions of organic isocyanates;
有机异氰酸酯的生产及市场消费状况
Clean synthesis of isocyanates;
异氰酸酯的清洁生产工艺进展
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