Ionic Nucleophilic Catalysis of Chiral Ammonium Betaines for Highly Stereoselective Aldol Reaction from Oxindole-Derived Vinylic Carbonates
作者:Daisuke Uraguchi、Kyohei Koshimoto、Takashi Ooi
DOI:10.1021/ja3022939
日期:2012.4.25
A new strategy for developing stereoselective bond-forming reactions is introduced; it takes advantage of the ionic nucleophilic catalysis of chiral ammonium betaines to utilize vinylic esters simultaneously as the enolate precursor and the acylating agent for coupling with electrophiles. Its synthetic utility is clearly demonstrated by the realization of a highly diastereo- and enantioselective aldol
介绍了一种开发立体选择性成键反应的新策略;它利用手性甜菜碱铵的离子亲核催化作用,同时利用乙烯基酯作为烯醇化物前体和酰化剂与亲电试剂偶联。由羟吲哚衍生的乙烯基碳酸酯实现高度非对映选择性和对映选择性羟醛反应清楚地证明了其合成效用。