分子内反应与分子内催化 Ⅲ.溶剂效应对 2-(2′-苯并咪唑基)乙酸乙酯及3-(2′-苯并咪唑基)丙酸乙酯碱性水解的影响  

Intramolecular Reaction and Intramolecular Catalysis Ⅲ. Solvent Effects on the Alkaline Hydrolysis of Ethyl 2-(2'-benzimidazolyl) acetate and Ethyl 3-(2'-benzimidazolyl) propionate

作　　者：夏道宏[1] 夏炽中[2] 

机构地区：[1]石油大学化学工程系,东营257062 [2]山西大学分子科学研究所,太原030006

出　　处：《化学学报》1994年第5期506-510,共5页Acta Chimica Sinica

基　　金：自然科学基金资助的项目

摘　　要：测定了2-(2′-苯并咪唑基)乙酸乙酯及3-(2′-苯并咪唑基)丙酸乙酯在DMSO-水、1,4-二氧六环-水混合溶剂体系中的碱性水解动力学.随着DMSO-H_2O混合溶剂中DMSO含量增加,两种酯水解表观速率常数分别呈现出不规则的钟形变化.实验结果与我们所提出的酯水解历程中既包括分子间氢氧根离子特殊碱催化又包括分子内苯并咪唑基一般碱催化两种催化方式相符合.The alkaline hydrolysis kinetics of ethyl 2-(2'-benzimidazolyl) acetate and ethyl 3-(2'-benzimidazolyl) propionate have been measured in DMSO-water, 1,4-dioxane-water mixed solvents, With the increase of DMSO volume content in the DMSO-water mixture, the observed hydrolysis rate constants of these two esters describe an irregular bell-shape curve respectively. The experimental results conform well to the proposed mechanism of the esters hydrolysis including both the intermolecular specific base catalysis of hydroxide ion and the intramolecular general base catalysis of benzimidazolyl group.

关 键 词：分子内催化 溶剂效应 酯水解反应 

分 类 号：O643.362[理学—物理化学]