Homolytic aromatic substitution of acyl radicals: Oxidative coupling of 2-methylquinolines with quinoxalines

Abstract

Oxidative coupling of 2-methylquinolines with quinoxalines via a TBHP ( t-butyl hydroperoxide) and TFA (trifluoroacetic acid) mediated Minisci reaction affords quinolin-2-yl(quinoxalin-2-yl)methanone derivatives. This approach provides a simple and efficient method to construct various acyl derivatives in moderate to good yields (45%–92%) without any metal catalyst. Mechanistically, homolytic aromatic substitution (HAS) of acyl radicals mediated by TBHP is crucial for the construction of the quinolin-2-yl(quinoxalin-2-yl)methanone products.