A process for the production of ªÐ-cymene from monocyclic terpenes

摘要

Monocyclic terpenes are dehydroganized for the production of p-cymene by heating with sulphur and one of the organic base catalysts used in the rubber industry as vulcanization accelerators, such as thiocarbanilide or di- or tri-phenylguanidine; the cymene is isolated by steam-distillation, whilst the residue, a sulphur-containing resinous mass of balsamic odour, can be used for therapeutic purposes. In an example, dipentene is heated with sulphur and thiocarbanilide, the product steam-distilled and the distillate purified by treating with permanganate solution and again steam-distilling; it can be still further purified by distilling over metallic calcium. Other terpenes mentioned are terpinolene and terpinene.