Applications of the intramolecular diels-alder reactions of heterodienes to the syntheses of indole alkaloids
作者:Stephen F. Martin、Brigitte Benage、Sidney A. Williamson、Stephen P. Brown
DOI:10.1016/s0040-4020(01)90579-4
日期:1986.1
being the pivotal intermediate for the preparation of the secondary amine 24 (13 steps and 18% overall yield from propargyl alcohol), a known precursor of tetrahydroalstonine (4) and other heteroyohimboid bases, as well as for the syntheses of the α,β-unsaturated 2-piperidones 27 and 29, model compounds that have been designed to test the feasibility of a new strategy for the synthesis of the corynantheioid
已经开发了一种新颖的分子内Diels-Alder反应,该反应涉及将α,β-不饱和醛添加至电子缺陷的亲二烯体伙伴中,这是开发异戊二烯和类胡萝卜素生物碱的一般方法的关键步骤。因此,可以容易地以八个步骤从炔丙醇进行的氮连接的三烯11的热环化进行得顺利,以73%的收率得到顺式-环加合物20。所述顺式β-内酰胺类20供应的被枢转中间体仲胺的制备中的双重作用24(13个步骤和18%炔丙醇的总产率),tetrahydroalstonine的已知前体(4)和其他杂类异戊二烯碱,以及α,β-不饱和2-哌啶酮27和29的合成,这些模型化合物已被设计用来测试一种新策略合成带有环糊精的类胡萝卜素生物碱的可行性。C(20)处的(E)-亚乙基部分。