Abstract

The synthesis of diastereoisomers via diastereoselective hydrogenation of unreactive endocyclic enamine system of ethyl 4-hydrazinyl- and 4-(2-hydroxyethylamino)-5-oxo-2,5-dihydro-1H-pyrrole-3-carboxylates using palladium-based catalyst was developed. The steric and electronic properties of substituents, especially of the C² substituent, influenced both the yield and diastereoselectivity. Despite the reaction generated three chiral centers, the reduced compounds had either cis–trans or all-trans configuration which was successfully determined by means of 1D and 2D NMR experiments.

中文翻译：

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多相钯催化剂介导的β-烯氨基氧吡咯烷羧酸盐的简便还原

摘要

使用钯基催化剂，通过对4-肼基-和4-（2-羟基乙基氨基）-5-氧代2,5-二氢-1 H-吡咯-3-羧酸乙酯的未反应内环烯胺系统进行非对映选择性加氢合成非对映异构体已开发。取代基，特别是C ²取代基的空间和电子性质，影响产率和非对映选择性。尽管反应生成了三个手性中心，但还原后的化合物仍具有顺-反或全-反构型，可通过1D和2D NMR实验成功确定。