Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055, United States.
Org Lett. 2011 Jun 3;13(11):2932-5. doi: 10.1021/ol2009895. Epub 2011 May 10.
A concise asymmetric synthesis of (+)-aphanorphine has been achieved via a new enantioconvergent strategy. A racemic γ-aminoalkene derivative is transformed into a 1:1 mixture of enantiomerically enriched diastereomers using an asymmetric Pd-catalyzed carboamination. This mixture is then converted to an enantiomerically enriched protected aphanorphine derivative by a Friedel-Crafts reaction, which generates a quaternary all-carbon stereocenter. The natural product is obtained in three additional steps.
通过一种新的对映体转化策略，实现了（+）-阿朴啡的简洁不对称合成。通过不对称钯催化的碳氨化反应，将外消旋γ-氨基烯烃衍生物转化为非对映异构体富集的对映体混合物（1:1）。然后，通过傅-克反应将该混合物转化为非对映异构体富集的保护阿朴啡衍生物，生成一个季碳全碳立体中心。通过另外三个步骤获得天然产物。
