Intramolecular Hydroarylation of Arenes via Imidazole-Directed C-H Activation in Aqueous Methanol Using Rhodium(III) as the Catalyst and Mechanistic Study.

A mild and greener approach for intramolecular regioselective hydroarylation is described for the efficient and elegant preparation of a number of dihydrobenzofurans and dihydrobenzo[]thiophenes using imidazole as a directing group and Rh(III) as a catalyst. Moreover, the protocol may be extended to the formation of indoline and chromane derivatives. Deuterium scrambling experiments and characterization of isolated rhodacycle intermediate were explored to understand the mechanism in a better way.