Multicomponent Linchpin Couplings. Reaction of Dithiane Anions with Terminal Epoxides, Epichlorohydrin, and Vinyl Epoxides: Efficient, Rapid, and Stereocontrolled Assembly of Advanced Fragments for Complex Molecule Synthesis
作者:Amos B. Smith、Suresh M. Pitram、Armen M. Boldi、Matthew J. Gaunt、Chris Sfouggatakis、William H. Moser
DOI:10.1021/ja0376238
日期:2003.11.1
The development, application, and advantages of a one-flask multicomponent dithiane linchpin coupling protocol, over the more conventional stepwise addition of dithiane anions to electrophiles leading to the rapid, efficient, and stereocontrolled assembly of highly functionalized intermediates for complex molecule synthesis, are described. Competent electrophiles include terminal epoxides, epichlorohydrin
描述了单瓶多组分二噻烷关键偶联方案的开发、应用和优势,而不是将二噻烷阴离子逐步添加到亲电试剂中,从而快速、高效和立体控制地组装用于复杂分子合成的高度官能化中间体。 . 有效的亲电试剂包括末端环氧化物、表氯醇和乙烯基环氧化物。使用表氯醇和乙烯基环氧化物可以实现高化学选择性。对于乙烯基环氧化物,二噻烷阴离子的空间性质至关重要;空间上不受阻碍的二噻烷阴离子提供 S(N)2 加合物,而受阻碍的阴离子主要导致 SN2' 加合物。机理研究表明 SN2' 过程是通过对乙烯基环氧化物的顺式加成而发生的。