Reactions of Dihydric Phenols

It is clear from the proposed mechanism that the initial step will be facilitated by the presence of a second hydroxyl group in the phenol, oriented meta to the first. In view of the importance of polyphenolic molecules in natural product chemistry, this synthesis takes on a special significance. Thus, the reaction of dihydric phenols with citral (65) has been used to synthesize a diverse range of natural products. However, such compounds can, and in some cases do, give rise to a mixture of isomeric products. Olivetol (64), for instance, yields a mixture of mono- and bis-chromenes of which cannabichromene (66) is a significant component (71JCS(C)796). On the other hand, the phenol (67) affords a h igh yield of isoevodionol (68) on reaction with 4,4-dimethoxy-2-methylbutan-2-ol (71JCS(C)8U). 

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