Iron-catalyzed cross-coupling of arylboronic acids with unactivated N-heterocycles and quinones under microwave heating

Abstract

The iron-catalyzed direct arylation of a variety of N-heteroarenes, quinones, and hydroquinones with arylboronic acids is investigated under microwave heating. The reaction proceeds at 70 °C under air using K2S2O8 as an oxidant and FeSO4 as a catalyst. Under microwave heating, reaction times decreased 14- to 115-fold. Reaction scope with N-heteroarenes and quinones is comparable with or slightly expanded when compared with previous reports, but the scope of arylboronic acid utility was slightly limited due to previously unobserved arylboronic acid hydroxydeboronation.