Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom.
J Org Chem. 2013 Feb 1;78(3):1098-106. doi: 10.1021/jo3025225. Epub 2013 Jan 10.
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 studies also suggest that the stereochemical outcome of the electrophile trapping depends on the electrophile used but is independent of which α-proton (cis or trans to the hydroxyl group) is initially removed.
N-硫代邻苯二甲酰基氮杂环丁-3-醇的α-锂化反应，以及随后的亲电试剂捕获反应，提供了一系列具有普遍良好的反式非对映选择性的 2-取代 3-羟基氮杂环丁烷，除了氘代反应得到顺式非对映异构体。氘标记研究表明，初始的α-脱质子化反应优先但并非排他性地以反式选择性方式发生。这些研究还表明，亲电试剂捕获的立体化学结果取决于所使用的亲电试剂，但与最初去除的哪个α-质子（羟基的顺式或反式）无关。
