A new method for the synthesis of pyrrolo[1,2-a]pyrazines and pyrrolo[1,2-a] quinoxalines

A new method is proposed for the synthesis of pyrrolo1,2-a]pyrazines and pyrrolo1,2-a]-quinoxalines. By the alkylation of sodium derivatives of 2-acylpyrroles with -bromo carbonyl compounds or their acetals and subsequent treatment of the reaction products with ammonium acetate in acetic acid, a number of derivatives of pyrrolo1,2-a]pyrazine, including the first member of the class, pyrrolo1,2-a]pyrazine itself, have been obtained. Similarly, from 2-benzoylpyrrole and the dimethyl ketal of -bromocyclohexanone was obtained 4-phenyltetrahydropyrrolo1,2-a]quinoxaline, which readily dehydrogenates in the presence of Raney nickel to form 4-phenylpyrrolo1,2-a]quinoxaline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 8, pp.1048–1050, August, 1970.