A concise synthesis of honokiol

A simple synthesis of the natural product honokiol 1 has been developed which proceeds in four steps and provides a 32% overall yield. Suzuki coupling of 4-allyl-2-bromoanisole 3 with 4-hydroxyphenyl boronic acid, followed by allylation, gave 5-allyl-4′-allyloxy-2-methoxy-biphenyl 5. This compound 5 underwent Lewis acid-catalyzed Claisen rearrangement and demethylation in a one-pot reaction which yielded honokiol.