Asymmetric synthesis of new chiral N-sulfinyl 2,2-disubstituted aziridines by Grignard additions across α-chloro N-sulfinyl ketimines
作者:Filip Colpaert、Sven Mangelinckx、Erika Leemans、Bram Denolf、Norbert De Kimpe
DOI:10.1039/c001471k
日期:——
Reaction of chiral α-chloro N-tert-butanesulfinyl ketimines with Grignard reagents afforded new chiral N-sulfinyl 2,2-disubstituted aziridines in good to excellent diastereomeric ratio (dr up to 98â:â2). The 1,2,2-trisubstituted aziridines were isolated in high overall yield (51â85%) and with excellent enantiomeric excess (>98% ee). The stereoselectivity obtained in the Grignard addition is rationalized by the coordinating ability of the α-chloro atom resulting in the opposite stereochemical outcome as observed for nonfunctionalized N-sulfinyl ketimines.
手性α-氯代N-特丁基亚磺酰基亚胺与Grignard试剂的反应,得到了新的手性N-亚磺酰基2,2-二取代氮杂环丙烷,其非对映体比例良好至优秀(最高达98:2)。1,2,2-三取代氮杂环丙烷的总产率很高(51-85%),并且具有极佳的立体选择性(>98% ee)。Grignard加成反应中获得的立体选择性,可归因于α-氯原子的配位能力,导致了与非官能化N-亚磺酰基亚胺相反的立体化学结果。