作者:Sun Young Lee、Jung Wha Jung、Tae-Hyun Kim、Hee-Doo Kim
DOI:10.1007/s12272-015-0641-4
日期:2015.12
The first asymmetric synthesis of (R,R)-clemastine (1) has been accomplished by the coupling of (R)-tertiary alcohol 2 and (R)-chloroethylpyrrolidine 3 via O-alkylation. (R)-Tertiary alcohol 2 was synthesized by stereoselective alkylation of chiral α-benzyloxy ketone with Grignard reagent via chelation-controlled 1,4-asymmetric induction. In the reaction, chiral benzyl group acts as a chiral auxiliary
(R,R)-clemastine (1) 的第一个不对称合成是通过 (R)-叔醇 2 和 (R)-氯乙基吡咯烷 3 通过 O-烷基化的偶联完成的。(R)-叔醇 2 是通过手性 α-苄氧基酮与格氏试剂通过螯合控制的 1,4-不对称诱导立体选择性烷基化合成的。在反应中,手性苄基作为手性助剂和保护基团。(R)-氯乙基吡咯烷 3 是通过从 l-高丝氨酸内酯开始的不对称转化制备的,其中外消旋化最小化 N-烯丙基化和闭环复分解作为关键步骤。