Palladium-catalyzed direct alkenylation of 2-methyl-4H-pyrido[1,2-a]pyrimidin-4-ones using oxygen as the oxidantElectronic supplementary information (ESI) available: 1H and 13C NMR spectra of compounds 3a-3u. See DOI: 10.1039/c5ra02932e

A direct C-3 alkenylation of 2-methyl-4 H -pyrido[1,2- a ]pyrimidin-4-ones through palladium-catalyzed C-H activation using oxygen as the terminal oxidant has been developed. This method provides an easy access to functionalized new 2-methyl-4 H -pyrido[1,2- a ]pyrimidin-4-one derivatives. A direct C-3 alkenylation of 2-methyl-4 H -pyrido[1,2- a ]pyrimidin-4-ones through palladium-catalyzed C-H activation using oxygen as the terminal oxidant has been developed.