Gold(I)-Catalyzed Addition of Thiols and Thioacids to 3,3-Disubstituted Cyclopropenes
作者:Richard J. Mudd、Paul C. Young、James A. Jordan-Hore、Georgina M. Rosair、Ai-Lan Lee
DOI:10.1021/jo300930c
日期:2012.9.7
Gold(I)-catalyzed reactions of thiols, thiophenols, and thioacids with 3,3-disubstituted cyclopropenes occur in a regioselective and chemoselective manner to produce either vinyl thioethers or primary allylic thioesters in good yields. A survey of commonly used gold(I) catalysts shows Echavarren’s cationic gold(I) catalyst to be most tolerant of deactivation by sulfur. A novel digold with bridging
complexes as a catalyst in dehydrative reactions with allylic alcohols. There is often an improvement in yield and, in particular, indium(III) chloride outperforms gold(I) as a catalyst in chemoselective reactions. For example, substrates with pendent alkyne or alkene groups react poorly under gold(I) catalysis, but are better tolerated under indium(III) chloride catalysis.