Efficient synthesis of substituted benzenes from 1,3-dienes or 1,4-cyclohexadienes with KMnO4 under mild conditions

Potassium permanganate absorbed on alumina is used to oxidize 1,4-cyclohexadienes to the corresponding aromatic compounds. Intermolecular Diels-Alder reactions followed by dehydrogenation of the products with potassium permanganate supported on alumina gives an efficient two step synthesis of highly substituted aromatic compounds from acyclic precursors.