(+)-Car-3-ene is an extremely versatile monoterpene. It is almost as abundant in nature as α- and β-pinenes. Though a constituent of numerous essential oils from the genus Pinus, perhaps the richest source is the oil of Pinus longifolia (Roxb.) in which it is present from 55 to 65%. (+)-Car-3-ene is also available in the by-product turpentine recovered from Kraft pulp mills.
For half a century, (+)-car-3-ene was relegated to the backyard of the Naval Stores Industry. More than anything else, lack of precise knowledge of its intricate chemistry and its non-availability in technical purity were responsible for this tragic negligence. Recent years have witnessed a dramatic change in the status of (+ )-car-3-ene. The terpene has blossomed into a unique raw material for modification to interesting and valuable perfumery synthetics.
