GENERAL BASE CATALYSIS OF ESTER HYDROLYSIS
GENERAL BASE CATALYSIS OF ESTER HYDROLYSIS
复制标题
DOI：
10.1021/ja01468a044
复制
发表时间：
1961-01-01
影响因子：
15
通讯作者：
CARRIUOLO, J
中科院分区：
文献类型：
--
作者：
JENCKS, WP;CARRIUOLO, J
在酰基部分活化的酯的水解，包括氯乙酸乙酯、二氟乙酸乙酯、乙草酰胺和甘氨酸乙酯盐酸盐，由一般碱催化。这种催化遵循布朗斯台德催化定律，斜率为0.47，对于二氯乙酸乙酯，在氧化氘溶液中降低2 - 3倍，不是催化碱的亲核反应性的函数，并且在苯胺的情况下，不会导致催化碱的酰化。与醇部分活化的酯相比，醇部分活化的酯受到碱的亲核催化，因此，酰基部分活化的酯似乎受到经典的一般碱催化水解。中性的，“非催化的”水解速率在氧化氘溶液中也降低了2 - 3倍，水福尔斯落在与其他一般碱相同的Bronsted图上，这表明这些酯的中性水解涉及水作为质子转移剂以及亲核试剂。早期的研究，特别是Dawson及其同事的研究，表明在乙酸乙酯水解中存在这种催化2 -4，Hinshelwood报道了在醇溶液中各种酸的酯化反应的一般酸催化。6然而，很难将这种类型的催化作用与盐效应6区分开来，至少在一种情况下，
The hydrolysis of esters activated in the acyl portion, including the ethyl chloroacetates, ethyl difluoroacetate, ethyl oxamide and glycine ethyl ester hydrochloride, is catalyzed by general bases. This catalysis follows the Bronsted catalysis law with a slope of 0.47, for ethyl dichloroacetate, is decreased two-to threefold in deuterium oxide solution, is not a function of the nucleophilic reactivity of the catalyzing base and, in the case of aniline, does not result in acylation of the catalyzing base. In contrast to esters activated in the alcohol portion, which are subject to nucleophilic catalysis by bases, it therefore appears that esters activatedin the acyl portion are subject to classicalgeneral base-catalyzed hydrolysis. The rate of neutral,“uncatalyzed” hydrolysis is also two-to threefold decreased in deuterium oxide solution and water falls on the same Bronsted plot as other general bases, suggesting that the neutral hydrolysis of these esters involves water as a proton transferring agent as well as a nucleophilic reagent.It has not been clear whether ester hydrolysis is subject to classical general acid-base catalysis. Early studies, particularly those of Dawson and co-workers, suggested the existence of such catalysis in ethyl acetate hydrolysis2-4 and Hinshelwood re-ported general acid catalysis of the esterification of a variety of acids in alcohol solution. 6 It has been difficult, however, to differentiate this type of catalysis from salt effects6 and in at least one case,