Highly enantioselective sequential hydrogenation of ethyl 2-oxo-4-arylbut-3-enoate to ethyl 2-hydroxy-4-arylbutyrate

Qinghua Meng; Lufeng Zhu; Zhaoguo Zhang

doi:10.1021/jo801140j

Highly enantioselective sequential hydrogenation of ethyl 2-oxo-4-arylbut-3-enoate to ethyl 2-hydroxy-4-arylbutyrate

J Org Chem. 2008 Sep 19;73(18):7209-12. doi: 10.1021/jo801140j. Epub 2008 Aug 22.

Authors

Qinghua Meng¹, Lufeng Zhu, Zhaoguo Zhang

Affiliation

¹ School of Chemistry and Chemical Technology, Shanghai Jiaotong University, 800 Dongchuan Road, Shanghai 200240, China.

PMID: 18722407
DOI: 10.1021/jo801140j

Abstract

The hydrogenation of (E)-ethyl 2-oxo-4-arylbut-3-enoate with [NH2Me2](+)[{RuCl [(S)-SunPhos]}2(mu-Cl3)] gave ethyl 2-hydroxy-4-arylbutyrate with 94-96% ee. Further investigation has proved that the hydrogenation proceeded via a sequential hydrogenation of CO and CC bonds, which is sensitive to the reaction temperature. Hydrolysis of ethyl 2-hydroxy-4-phenylbutyrate (ee 93%) provided the 2-hydroxy-4-phenylbutyric acid with 81% yield at 99% ee after a single recrystallization from 1,2-dichloroethylene.