Synthesis of Optically Active Tricyclic Ethers by Reactions of (−)‐β‐Pinene with Phenols in Organized Media

The reactions of (?)‐β‐pinene ( 1 ) with some methyl‐ and hydroxy‐substituted phenols on Hβ‐zeolite yield optically active products – tricyclic terpenyl phenyl ethers – in contrast to reactions in homogeneous media, which occur with loss of optical activity. The formation of these products is promoted by the presence of meta‐substituents in the phenol molecule.