Synthesis and Diels–Alder reactions of α-fluoro- and α-trifluoromethylacrylonitriles
摘要:
A novel synthetic method for the preparation of alpha-fluoro- and the still unknown alpha-trifluoromethylacrylonitriles is elaborated. The reaction of alpha-fluorovinylbromides and alpha-trifluoromethylvinylbromides with CuCN leads to the title compounds in good to high yields. While the alpha-fluoroacrylonitriles were isolated as mixture of Z/E-isomers, the alpha-trifluoromethylacrylonitriles were obtained as pure Z-isomers. The alpha-trifluoromethylacrylonitriles are shown to be excellent dienophiles for Diels-Alder reactions. (c) 2007 Elsevier B.V. All rights reserved.
Stereoselective synthesis of α-fluoroacrylonitriles <i>via</i> organocatalytic cyanation of <i>gem</i>-difluoroalkenes and TMSCN
作者:Yu-Chuan Ma、Yang Zhang、Cheng-Zhi Gu、Guang-Fen Du、Lin He
DOI:10.1039/c9nj02370d
日期:——
An organocatalytic cyanationreaction of gem-difluoroalkenes was developed. Under the catalysis of 10 mol% DBU, gem-difluoroalkenes undergo a nucleophilic addition-β-elimination reaction with trimethylsilylcyanide to provide α-fluoroacrylonitriles in 50–98% yields with excellent Z/E selectivity.