The terpineols and their esters are extensively employed in the fragrance and flavor industry. Commercial terpineol is usually prepared by the treatment of terpin hydrate with dilute acid in an aqueous medium. The product comprises largely alpha-terpineol together with about 15% beta-terpineol and 15% gamma-terpineol. It is difficult to separate gamma-terpineol from alpha-isomer and, even using gas-liquid chromatography methods, only partial separation could be achieved.
Commercial terpinyl esters applied in the perfumery and cosmetic industry are usually prepared by esterification of terpineol. The mixture consists alpha-, beta- and gamma-isomers, in which the predominant component is alpha-isomer.
Pure alpha and beta terpineols have different odour properties; therefore, the same phenomenon could be expected for their esters. Physiochemical and odour properties of pure beta-terpinyl esters were not reported in literature. Their synthesis by direct esterification could not be realized because the pure alcohol is not easily available. Our efforts were directed to the synthesis of pure beta-terpinyl esters and comparison of their odour properties with commercial esters containing mainly the alpha isomer.
