The Synthesis of Novel Cyclic β-Amino Acids as Intermediates for the Preparation of Bicyclic β-Lactams
作者:Wolfgang Maison、Marc Kosten、Audrey Charpy、Jürgen Kintscher-Langenhagen、Imre Schlemminger、Arne Lützen、Ole Westerhoff、Jürgen Martens
DOI:10.1002/(sici)1099-0690(199909)1999:9<2433::aid-ejoc2433>3.0.co;2-x
日期:1999.9
homopipecolic acid are prepared by α-amino alkylation of malonic acid with cyclic imines 6 and 7. These are prepared on a large scale and with different substitution patterns. The β-amino acids 8 and 9 were formed in high yield and with remarkable diastereoselectivity if chiral imines are used as starting materials. The diastereoselectivity of the amino alkylation leading to homopipecolic acid analogues
通过丙二酸与环状亚胺 6 和 7 的 α-氨基烷基化制备了高哌啶酸的几种衍生物。这些是大规模制备的,具有不同的取代模式。如果使用手性亚胺作为起始原料,β-氨基酸 8 和 9 会以高产率和显着的非对映选择性形成。通过差向异构化实验将导致高哌啶酸类似物的氨基烷基化的非对映选择性与噻唑烷乙酸的非对映选择性进行比较。描述了通过形成非对映体盐来拆分获得的外消旋 β-氨基酸的方法。β-氨基酸 9 和 15 被转化为它们相应的碳酰苯丙胺类似物 14 和异戊烷 16。