Triphenylphosphine dibromide and dimethylsulfide dibromide as versatile reagents for beta-lactam synthesis
作者:Fernando P. Cossío、Iñaki Ganboa、Claudio Palomo
DOI:10.1016/s0040-4039(00)98613-1
日期:1985.1
Triphenylphosphinedibromide and dimethylsulfide dibromide are efficient reagents for the direct synthesis of beta-lactams from carboxylic acids and imines avoiding the use of acid halides as starting materials. Synthesis of 4-imino-beta-lactams are also briefly described. A potential synthesis of N-unsubstituted beta-lactams is made.
Remarkable ketene substituent dependent effect of photo irradiation on the diastereoselectivity in the Staudinger reaction
作者:Zhanhui Yang、Jiaxi Xu
DOI:10.1016/j.tetlet.2011.12.003
日期:2012.2
Controlling diastereoselectivity is a challenging issue in the Staudinger reaction. The influence of ultraviolet irradiation on the stereoselectivity in the Staudinger reaction has been investigated. The results indicate that ultraviolet irradiation is one of the most important means to regulate the diastereoselectivity of the products in the Staudinger reaction, whatever ketenes were generated from