A new copper(II) bromide/N-methylmorpholine N-oxide (NMO)-promoted method for α-amination of esters under continuous-flow conditions, with reduced catalyst loading is reported. The α-amino esters are precursors for the synthesis of α-amino acids. This method provides α-amino esters in 58–83% yields. The desired Cu(II)Br catalyst is regenerated by in situ oxidation of Cu(I)Br in the presence of NMO
报道了一种新的溴化铜( II )/ N-甲基吗啉N-氧化物(NMO)促进的连续流动条件下酯的α-胺化方法,并减少了催化剂负载量。α-氨基酯是合成α-氨基酸的前体。该方法提供 α-氨基酯,产率为 58-83%。所需的 Cu( II )Br 催化剂通过在 NMO 存在下原位氧化 Cu( I )Br来再生。
Oxidative Coupling of Indoles with Ethyl 2-(Disubstituted Amino)Acetates: An Approach to Achieve Indolylglycine Derivatives
作者:Zhanwei Xu、Xiaoqiang Yu、Xiujuan Feng、Ming Bao
DOI:10.1021/jo301035h
日期:2012.8.17
An efficient method for the synthesis of indolylglycine derivatives is described. The oxidativecoupling reactions of ethyl 2-(disubstituted amino)acetates with indoles proceeded smoothly in the presence of meta-chloroperoxybenzoic acid (mCPBA) under ambient conditions to produce indolylglycine derivatives in satisfactory to excellent yields.