Diazabutadienes in heterocyclic syntheses: reaction of 1,3-diazabutadienes with 2-oxazolin-5-ones

Abstract (4+2) Cycloaddition reactions of 1-aryl-4-dimethylamino-2-phenyl-1,3-diazabutadienes with 2-oxazolin-5-ones leading to pyrimidin-6-ones are reported.