Dual reactivity of 1,2-disubstituted dihydro-N-heteroaromatic systems. 8. Aromatization of N-acyl partly hydrogenated pyrazine and quinoxaline derivatives
N-mono- and N,N-diacyl 2,3-diindolyl-substituted 1,2-dihydro- and 1,2,3,4-tetra-hydropyrazines and quinoxalines were aromatized with triphenylmethyl perchlorate and 2,2,6,6-tetramethyl-1-oxo-piperidinium perchlorate. The hitherto unknown N-acylquinoxalinium perchlorates were obtained.