α-Lithiation–Electrophile Trapping of <i>N</i>-Thiopivaloylazetidin-3-ol: Stereoselective Synthesis of 2-Substituted 3-Hydroxyazetidines
作者:David M. Hodgson、Christopher I. Pearson、Amber L. Thompson
DOI:10.1021/jo3025225
日期:2013.2.1
α-Lithiation of N-thiopivaloylazetidin-3-ol and subsequent electrophile trapping provides access to a range of 2-substituted 3-hydroxyazetidines with generally good trans-diastereoselectivity, aside from deuteration, which gives the cis-diastereoisomer. Deuterium labeling studies indicate that the initial α-deprotonation occurs preferentially, but not exclusively, in a trans-selective manner. These
N-硫代吡咯烷酮氮杂-3-醇的α-锂化和随后的亲电捕集提供了除氘以外的具有通常良好的反式-非对映选择性的一系列2-取代的3-羟基氮杂环丁烷的途径,这产生了顺式-非对映异构体。氘标记研究表明,初始的α-去质子化优先但非排他地以反选择方式发生。这些研究还表明,亲电试剂捕集的立体化学结果取决于所用的亲电试剂,但与最初去除哪个α-质子(顺式或反式为羟基)无关。