Dimerization of resveratrol trimethyl ether by phosphotungstic acid, structure confirmation of resformicol A and B

Dimerization of the trimethyl ether of resveratrol catalyzed by phosphotungstic acid gave two tetralins and a naphthalene derivative. The structure of the tetralins was obtained by X-ray crystallography and confirms the reported stereochemical configuration of resformicol A and B.