Brominated 4-(trifluoromethyl)pyrimidines: A convenient access to versatile intermediates

An expedient route to all three monobrominated and all three dibrominated isomers of 4-(trifluoromethyl)pyrimidine, and to several other halogenated pyrimidines, is described. Key steps are the electrophilic introduction of the halogen in the 5-position of 2- or 4-pyrimidinones, the bromodeoxygenation of pyrimidinones or thiopyrimidinones using phosphorus tribromide, and the partial debromination of dibromo-4-(trifluoromethyl)pyrimidines. [on SciFinder (R)]