利用手性N-氰乙基-2-羟基蒎烷-3-酮亚胺合成光学活性2-乙基环丙烷氨基酸

Asymmetric Synthesis of Optically Active 2 Ethyl 1 Amino cyclopropanecarboxylic Acid via Pianone Ketimine

以２－羟基蒎烷－３－酮（１）与氨基乙腈缩合得到的手性酮亚胺（２）为中间体，经去质子化，在Ｐｄ（０）催化下与１，４－二氯－２－丁烯（３）发生串联反应，得到光学活性环丙烷衍生物（４），产率约为７０％，反应的非对映立体选择性（ｄ．ｅ．）为１００％．化合物４经选择性还原后水解，即可制得光学活性２－乙基环丙烷氨基酸，产物的对映体过量（ｅ．ｅ．）为３３％．

Optically active cyclopropanes(4) were obtained by using 2 hydroxypinan 3 one 1 as a chiral auxiliary, condensed with aminoacetonitrile to form a chiral ketimine 2 followed by Pd(0) catalyzed tandem alkylation and S N cyclisation of 1,4 dichlorobut 2 ene 3 with chiral ketimine 2. The yields are 69% and the diastereoselectivities of reaction are 100%. After the selective reduction of ethenyl group of 4, then by simple acid hydrolysis, optically active 2 ethyl 1 amino cyclopropanecarboxylic acid 6 could be obtained, the e.e. value of 6 is 33%.