PRODUCTS FROM THE ACID-CATALYZED REACTION OF CYCLIC MONOTERPENES AND PHENOL

Nine phenol-containing products from the acid-catalyzed reaction of ph enol and gamma-terpinene were isolated and identified. A combination o f X-ray crystallographic and spectroscopic techniques was used to assi gn the structures of the three p,p-bisphenols, two og-bisphenols, two bicyclic monophenols, and two bicyclic phenyl ethers. Several of the i ndividual reaction products interconverted under acid-catalyzed condit ions. The same nine products were formed using 3-carene, alpha-pinene, Limonene, or sabinene in place of gamma-terpinene, although the relat ive concentrations of these products varied depending upon the startin g monoterpene's structure. A mechanism is proposed which accounts for the products' structures and reactivities.