A method for preparing a cis-olefin of the formula :
R1-CH=CH-R2 by reducing an alkyne of the formula:
R1-C≡C-R2 with formic acid in the presence of a palladium catalyst. R1 and R2 are independently selected from the group consisting of a hydrogen atom, ester group, substituted silyl group, carboxyl group, cyano group, aliphatic CI-C20 hydrocarbon group, and phenyl group. The cis-olefin which is a useful intermediate for the synthesis of fine chemicals is selectively produced in high yields.
Direct formylation of phenols using difluorocarbene as a safe CO surrogate
作者:Cong-Cong Feng、Song-Lin Zhang
DOI:10.1039/d2ob02128e
日期:——
A convenient method to prepare aryl formates is reported herein that exploits difluorocarbene to serve as a CO surrogate. This reaction is proposed to occur through a sequential O-difluoromethylation of phenol, followed by α-C–F bond functionalization of the resulting aryl difluoromethyl ether intermediate by phenol or moisture through fluorosemiacetal or orthoformate intermediates. Late-stage modification
本文报道了一种制备甲酸芳酯的便捷方法,该方法利用二氟卡宾作为 CO 替代物。该反应被认为是通过苯酚的顺序O-二氟甲基化,然后通过苯酚或水分通过氟半缩醛或原甲酸酯中间体对所得芳基二氟甲基醚中间体进行 α-C-F 键官能化而发生的。证明了生物和材料活性化合物的后期修饰。