Other Reactions of Pinene

A study of the hydration and isomerization of 1 over zeolite beta in water yielded the expected monocyclic alcohol, a-terpineol (4) [13]. This isomerization/hydra-tion in the presence of zeolite beta is a rapid process and yields up to 48 % of 4. 

It was found that the rate of the reaction and selectivity towards formation of 4 could both be increased by dealumination of the outer surface of the zeolite with Na2H2EDTA. When the solvent was changed to pure acetone a new compound (5) was formed. In this study, the coupling of ketones (acetone, butanone, and cyclohexanone) with 1 was found to be catalyzed solely by zeolite beta. The reaction also seems to be exclusive to a-pinene, because no reaction occurred when other terpenes such as 3, 4, and borneol (6) were used in place of a-pinene. It is also worth noting that borneol (6) has also been prepared from 1 by use of a high-silica zeolite [14], 

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