The present invention provides transition-metal-catalyst-based methods for the arylation and vinylation of activated methyl, methylene, and methine carbons with aryl halides, vinyl halides, and the like. The methods of the invention provide several improvements over existing methods, including the ability to synthesize efficiently and under mild conditions α-aryl and α-vinyl products from a wide range of starting materials, including ketones, esters, hydrazones, and imines. Furthermore, the methods of the invention may be used in an asymmetric sense, i.e. to produce enantiomerically-enriched chiral α-aryl and α-vinyl products.
Highly Active and Selective Catalysts for the Formation of α-Aryl Ketones
作者:Joseph M. Fox、Xiaohua Huang、André Chieffi、Stephen L. Buchwald
DOI:10.1021/ja993912d
日期:2000.2.1
biphenyl backbone, when combined with Pd(OAc)2, give highly active catalysts for the α-arylation of ketones. The ligand 2-methyl-2‘-dicyclohexylphosphinobiphenyl is particularly effective, and with 0.1−1.0 mol % Pd, a large variety of aryl halides and ketones react efficiently and with high selectivity. For two types of substrates, the ligands BINAP and Xantphos are more effective than the biphenyl-based