4-Chloromethylene-2-phenyl-5 (4H)-oxazolone 1 was used as the starting material for the preparation of a series of 4-ylideneoxazolones 3 by the Stille reaction. When compound 1 was reacted with organostannanes 2 in the presence of the palladium catalyst, oxazolones 3 were obtained in good yields in mild reaction conditions.