A new, efficient and easy route for the preparation of a series of 2-alkyl (aryl) substituted 4- oxo-4H-pyrido-[1, 2-a] pyrimidines, where alkyl= CH3; aryl= C6H5, 4-FC6H4, 4-ClC6H4, 4- BrC6H4, 4-CH3C6H4, 4-OCH3-C6H4, 4-NO2C6H4 in 45–80% yield from the reaction of β- alkoxyvinyl trichloromethyl ketones with 2-aminopyridine under mild conditions, is then reported.