Synthesis of stilbene and distyrylbenzene derivatives through rhodium-catalyzed ortho-olefination and decarboxylation of benzoic acids.

Ortho-substituted benzoic acids efficiently undergo precisely ordered ortho-olefination/decarboxylation upon treatment with styrenes in the presence of a rhodium catalyst and silver salt oxidant to afford the corresponding meta-substituted stilbene derivatives. The selective syntheses of 1,3- and 1,4-distyrylbenzenes have also been realized through the reactions of simple benzoic acid and phthalic acid, respectively, with styrene under similar conditions.