（Z）-α-卤代丙烯酸酯：通过Cr（II）介导的醛与三卤乙酸酯的烯化反应实现的异常立体选择性制备方法。

(Z)-alpha-haloacrylates: an exceptionally stereoselective preparation via Cr(II)-mediated olefination of aldehydes with trihaloacetates.

作者信息

Barma D K, Kundu Abhijit, Zhang Hongming, Mioskowski Charles, Falck J R

机构信息

Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390-9038, USA.

出版信息

J Am Chem Soc. 2003 Mar 19;125(11):3218-9. doi: 10.1021/ja029938d.

DOI:10.1021/ja029938d

PMID:12630869

Abstract

(Z)-alpha-Fluoro-, (Z)-alpha-chloro-, and (Z)-alpha-bromoacrylates were obtained with unprecedented yield and stereocontrol (>99%) via addition of the corresponding commercial trihaloacetates to aldehydes at room temperature using stoichiometric Cr(II) salts or catalytic Cr(II) with a regeneration system. The intermediate 2,2-dihalo-3-hydroxy adducts could be isolated in good yields under conditions of limited reagent at 0 degrees C.

摘要

通过在室温下使用化学计量的Cr(II)盐或带有再生系统的催化Cr(II)，将相应的市售三卤乙酸酯加成到醛上，以空前的产率和立体控制（>99%）得到了(Z)-α-氟丙烯酸酯、(Z)-α-氯丙烯酸酯和(Z)-α-溴丙烯酸酯。在0℃有限试剂的条件下，可以以良好的产率分离出中间体2,2-二卤-3-羟基加合物。