Direct Introduction of Ethoxycarbonyldifluoromethyl-Group to Heteroarenes with Ethyl Bromodifluoroacetate via Visible-Light Photocatalysis
作者:Qingyu Lin、Lingling Chu、Feng-Ling Qing
DOI:10.1002/cjoc.201300411
日期:2013.7
A mild and versatile approach for the directintroduction of ethoxycarbonyldifluoromethyl‐group to heteroarenesvia visible‐light photocatalysis has been developed. The new photoredox protocol has enabled the difluoromethylenation of heteroarenes containing a wide range of common functional groups under mild conditions.
Copper‐Catalyzed C−H Difluoroalkylation of Coumarins with Fluoroalkyl Bromides
作者:Min Rao、Zhenwei Wei、Yaofeng Yuan、Jiajia Cheng
DOI:10.1002/cctc.202001025
日期:2020.10.20
An efficient method for the copper‐catalyzed selective C−H difluoroalkylation of coumarins and with low cost and readily available ethylbromodifluoroacetate and N‐phenyl bromodifluoroacetamide has been reported. This reaction exhibits good functional group tolerance with respect to coumarins and difluoroalkylation reagents, and several redox‐sensitive substrates have been successfully C−H difluoroalkylated
Novel and facile aromatic and heteroaromatic substitutions with difluoromethyl radicals bearing electron-withdrawing group generated by the photo-initiated Se-CF 2 bond cleavage of ethyl α,α-difluoro-α-(phenylseleno)acetate and diethyl α,α-difluoromethyl-α-(phenylseleno)phosphonate were successfully carried out to provide the corresponding a-aryl-α,α-difluoroacetates and α-aryl-α,α-difluoromethylphosphonates
We report herein the first copper-catalyzed C-2 difluoromethylation of furans and benzofurans. The developed methodology allows the selective introduction of the CF2CO2Et moiety at C-2 using CuI as a catalyst. This process was applied to a broad range of furans and benzofurans, giving the functionalized products in moderate to good yields. The resulting products were then decarboxylated to afford the highly valuable C-2-CF2H-substituted furans and benzofurans in good yields.