A short, enantioselective synthesis of (−)-epilupinine from proline via a spirocyclic ammonium ylide
作者:B.N. Naidu、F.G. West
DOI:10.1016/s0040-4020(97)01037-5
日期:1997.12
quinolizidine 8b with high diastereoselectivity (19:1 8b/7b) and in surprisingly high enantiomeric excess (75%). The key step presumably occurs via spirocyclic ylide 6b, which undergoes [1,2]-shift with retention. Rearrangement product 8b was converted to (−)-epilupinine 2 via an efficient, 3-step sequence.
重氮酮5B,在从脯氨酸苄酯一步可用,后行转化为喹8B具有高非对映选择性(19:1的8b / 7B)和令人惊奇的高对映体过量(75%)。关键步骤大概是通过螺环内酯6b发生的,螺环内含物经历[1,2]移位。重排产物8b通过有效的3步序列转化为(-)-癫痫碱2。