A short and efficient protocol for the synthesis of imidazo[1,5-a]quinoxalin-4-ones from 3-aroylquinoxalinones and compounds with the aminomethylene moiety

The reaction of 3-aroylquinoxalin-2(1H)-ones with α-amino acids and their derivatives, amines with various alkyl groups, amino alcohols with alkylene groups of various length, N-(3-aminopropyl)morpholine and 1,6-diaminohexane in DMSO at 150 °C proceeds through the oxidative cyclocondensation and makes it possible to synthesize substituted imidazo[1,5-a]quinoxalines. Depending on the compound with the aminomethylene fragment used the reaction allows to introduction of any given substituent into position 1.