Practical and scalable synthesis of orthogonally protected-2-substituted chiral piperazines
作者:Srinivas Chamakuri、Manuj M. Shah、David C. H. Yang、Conrad Santini、Damian W. Young
DOI:10.1039/d0ob01713b
日期:——
orthogonally protected, enantiomerically pure 2-substituted piperazines is described. Starting from α-amino acids, within four steps chiral 2-substituted piperazines are obtained. The key transformation involves an aza-Michael addition between an orthogonally bis-protected chiral 1,2-diamine and the in situ generated vinyl diphenyl sulfonium salt derived from 2-bromoethyl-diphenylsulfonium triflate
描述了一种正交保护的、对映体纯的 2-取代哌嗪的合成路线。从 α-氨基酸开始,在四步内获得手性 2-取代哌嗪。关键的转化涉及正交双保护手性 1,2-二胺和原位生成的由 2-溴乙基-二苯基锍三氟甲磺酸盐衍生的乙烯基二苯基锍盐之间的氮杂迈克尔加成。进行了使用不同保护基团的进一步验证以及多克规模的合成。该方法还应用于手性1,4-二氮杂环己烷和1,4-二氮杂环己烷的构建。此外,该方法用于手性米氮平的正式合成。