Thiones as Reactive Intermediates in Condensations of Diketones with Aromatics Mediated by Tetraphosphorus Decasulfide

Phenanthrene-9,10-quinone and P 4 S 10 react with phenols on being heated to give oxathiins, e.g., 9 the dioxin 22 , ethers, e.g., 14 arylphenanthrenols, e.g., 10 and furanols, e.g., 17 in addition to sulfides, e.g., 26 and disulfides, e.g., 25 . Under similar conditions benzil gives thiophene derivatives, e.g., 2 . Most of the reactions appear to proceed via thione intermediates but some of the products are also formed when P 4 S 10 is absent.