Facile synthesis of biarylmethanes and tetrasubstituted arenes via a base-mediated [3 + 3] benzannulation reaction of Morita-Baylis-Hillman adducts and unsaturated sulfones.

ABSTRACT

A facile DBU-mediated [3 + 3] benzannulation reaction of 1,3-bis-sulfonyl propenes and Morita-Baylis-Hillman (MBH) bromides is described. The benzannulation reaction afforded bis-sulfonyl biarylmethanes/arenes with complete regioselectivity. The products may be converted readily into corresponding benzophenones via site-selective benzylic oxidation.