Two Protocols for the Conversion of Biphenol to Binaphthol: Synthesis of Diospyrol

The application of directed orthometallation (DoM), Fries rearrangement and transmetallation followed by allylation and cyclization is reported for the conversion of biphenol to binaphthol as a means for the synthesis of diospyrol. Furthermore, the same transformation can be accomplished by the reaction of the dienolate anion of an alpha,beta-unsaturated amide with an aryne intermediate.