α-Pinene is the most widespread pinene isomer. (+)-α-Pinene, (1R,5R)-2,6,6-trimethylbicyclo[3.3.1]hept-2-ene, occurs, for example, in oil from Pinus
palustris Mill., at a concentration up to 65%; oil from Pinus pinaster Soland and
American oil from Pinus caribaea contain 70% and 70–80%, respectively, of the
laevorotatory isomer, (?)-α-Pinene, (1S,5S)-2,6,6-trimethylbicyclo[3.3.1]hept-2-ene.
α-Pinene undergoes many reactions, of which the following are used in the fragrance
industry: upon