Afacilesolidphasesynthesisof2-substituted1,3-oxazin-6-onesusingpolymer-supportedMeldrum'sacidhasbeenreported.Reactionoftheresin-boundcyclicmalonicacidesterwithtriethylorthoformateandsubsequentdoublesubstitutionwithamide,affordedthecorrespondingpolymer-supportedacylaminomethylenecyclicmalonicacidester,whichuponthermaltreatmentledto1,3-oxazin-6-onesingoodyieldsandwithhighpurity.