Palladium-catalyzed Hiyama cross-couplings of 2-chloro pyrimidines with organosilanes

An efficient synthesis of C2-aryl pyrimidine derivatives via Pd-catalyzed Hiyama couplings has been developed. Various 2-chloro pyrimidines with electron-donating or electron-withdrawing groups as novel electrophile partners coupled well with trimethoxy(phenyl)silane and vinyltrimethoxysilane in the presence of CuCl and TBAF, providing desired products in good to excellent yields. This procedure showed good functional group tolerance, and the electronic and steric effects of 2-chloro pyrimidines seem to be negligible for the transformation.