Computational and experimental evidence for Sb(v) metal mediated C-H activation and oxidative functionalization of arenes.

Inorganic Sb complexes are one of the most well-known Lewis acids that typically indirectly activate nonpolar hydrocarbon bonds by acting as Brønsted superacids. Here we have used a combination of quantum-chemical calculations and experiments to demonstrate that inorganic Sb complexes can directly activate aromatic sp C-H bonds and induce oxidative functionalization to form aryl esters. C-H activation was first demonstrated by reaction of Sb(TFA) (TFA = trifluoroacetate) with toluene at moderate temperatures that resulted in Sb-C bond intermediates (TFA)Sb(-tolyl) and (TFA)Sb(-tolyl).