(2R,4S)-4-甲基-2-哌啶甲酸乙酯的合成

Synthesis of( 2R,4S)-ethyl 4-Methyl-2-piperidinecarboxylate

以S-(-)-α-苯乙胺为原料,经一锅法制得1-(1-苄基)-6-乙氧羰基-4-甲基-3,4-二氢哌啶(3),收率58.7%。以10%Pd/C为催化剂,3经催化氢化脱苄合成了4-甲基-2-哌啶甲酸乙酯(4),收率96%;4通过减压分馏得(2R,4S)-4,含量95%,其结构经1H NMR,IR和MS确证。

1-（S-1-benzyl）-6-ethoxycarbonyl-4-methyl-3,4-didehydropiperidine （3） in yield of 58.7％ was prepared by one-pot from （S）-1-phenylethylamine.Ethyl 4-methyl-2-piperidinecarboxylate （4） in yield 96％ was synthesized by catalytic hydrogenation debenzylation of 3 using 10％ Pd/C as the catalyst.（2R,4S）-4 with 95％ content was obtained by vacuum distillation of 4.The structures were confirmed by 1H NMR,IR and MS.