Synthesis of diaza-anthraquinones by hetero Diels-Alder cycloaddition reactions

Abstract Using 3-methyl-1-dimethylamino-1-azabuta-1,3-diene and 3( tert -butyldimethylsilyl)oxy-1-dimethylamino-1-azabuta-1,3-diene as 1-azadienes-and quinoline-5,8-dione and carbostyrilquinone as dienophiles, several diazaanthraquinones have been obtained. Structure assignments were mainly based on IR spectroscopic data. The accessibility of N-oxidation products has been also investigated.