The reaction of dimethyl sulfoxide-polyphosphoric acid mixture with benzylic alcohols has been shown to afford a complex mixture of the products; this is in contrast to the case of aliphatic alcohols, which yield the corresponding acetal as the major product. By carrying out reactions using several benzylic alcohols and a series of benzyl alcohols, it was found that, in addition to the acetal formation reaction, dehydration and oxidation reactions, as ...