Asymmetric Synthesis of (S)-4-Oxopipecolic Acid by a 3+3 Atom-Unit Assembly Strategy
作者:Karolin Partogyan-Halim、Laure Besson、David J. Aitken、Henri-Philippe Husson
DOI:10.1002/ejoc.200390028
日期:2003.1
(S)-4-Oxopipecolic acid has been prepared in enantiomerically pure form from two readily accessible starting materials, (R)-N-(cyanomethyl)-4-phenyloxazolidine (2) and 2-(methoxymethoxy)allyl chloride, (3, MOM-allyl chloride). This strategy exploits the complementary electrophile/nucleophile reactivity at each end of this pair of 3-atom unit building blocks. Thus, alkylation of the anion of 2 with
(S)-4-Oxopipecolic 酸已从两种容易获得的起始原料 (R)-N-(氰甲基)-4-苯基恶唑烷 (2) 和 2-(甲氧基甲氧基) 烯丙基氯 (3, MOM-烯丙基氯)。该策略利用了这对 3 原子单元构建块每一端的互补亲电试剂/亲核试剂反应性。因此,2 的阴离子与 3 的烷基化(哌啶 C-2-C-3 键的产生),然后是路易斯酸诱导的环化(C-5-C-6 键的产生),主要导致双环中间体5,其中包含标题化合物的受保护形式。随后的化学转化导致目标分子在五步序列中的总产率为 20%。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)