The chemistry of terpenes. Part VI. Pyrolysis and acid-catalysed rearrangements of (+)-car-3-ene and some derivatives
Abstract
Under otherwise similar conditions, (+)-car-3-ene requires higher temperatures to promote its vapour-phase pyrolysis than are required for the pinenes. Without catalyst (+)-car-3-ene gives principally aromatic products, but in the presence of a potassium aluminosilicate catalyst it affords hydroaromatic products by an ionic mechanism. The products of pyrolysis and acid-catalysed rearrangement of (–)-cis-caran-cis-5-ol and (–)-trans-caran-cis-2-ol, similarly dependent upon conditions, are described.