POLY(ETHYLENIMINES) WITH ALTERNATIVE (ALKYLAMINO)PYRIDINES AS NUCLEOPHILIC CATALYSTS
POLY(ETHYLENIMINES) WITH ALTERNATIVE (ALKYLAMINO)PYRIDINES AS NUCLEOPHILIC CATALYSTS
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DOI：
10.1021/ja00367a025
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发表时间：
1982-01-01
影响因子：
15
通讯作者：
KLOTZ, IM
中科院分区：
文献类型：
--
作者：
DELANEY, EJ;WOOD, LE;KLOTZ, IM
A series of substituted aminopyridines havebeen synthesized and attached topoly (ethylenimines). These modified polymers are markedly effective catalysts of the hydrolysis of nitrophenyl esters. At pH 7.3, the observed rates of hydrolysis of p-nitrophenyl caproate are 50-2000-fold greater than for the isolated aminopyridine. Variations in effectiveness with differences in structure of the nucleophile and with itscontent on the polymer have also been examined, and these have been interpreted in terms of the conformation and properties of the macromolecule.Since poly (ethylenimine) derivatives with apolargroups atta-ched covalently show strong affinities for binding of small mol-ecules in aqueous solution, we have been examining several co-valently linked nucleophiles for their potential as catalysts in reactions of these molecules. 1 Following the reports by Steglich, Hofle, and Vorbriiggen2’3 that (dialkylamino) pyridines are ex-cellent acylation catalysts, we prepared poly (ethylenimine) derivatives with 3-[methyl (4-pyridyl) amino] propionic acid (1) linked to the polymer. 4 These were found to be superior to previous polymer catalysts of hydrolysis of nitrophenyl esters in aqueous solution.
