5-Fluoro-1,3-dimethyluracil may be used as starting material in the following processes:Regioselective synthesis of tetrahydronaphthocyclobuta[1,2-d]pyrimidinediones.To synthesize 5-bis(ethoxycarbonyl)methyl-1,3-dimethyluracil.To synthesize new highly conjugated propenylidene derivatives via aromatic Paterno-Buchi type cycloaddition with 1-methoxynaphthalene.