A One-Pot Benzene - Naphthalene Transformation

Vicarious Nucleophilic Substitution Routes from Simple to 

VNS in recent years has become a valuable and in many instances powerful method for the regiospecific functionalisation of aromatic and heteroaromatic compounds. In a recent study, for example, it was shown that aluminium chloride-catalysed phenylsulfinylation of p-cresol followed by treatment of the product with (a) thionyl chloride, or (b) acetic anhydride/sodium acetate, or (c) p-cresol and TFAA gave, respectively, (a) 2-chloro-4-methyl-6-(phenylthio)phenol, or (b) 2-acetoxy-4-methyl-6-(phenylthio)phenol, or (c) 2,2 -dihydroxy-5,5 -dimethyl-3-(phenylthio)biphenyl. Yields varied from moderate to good (30-78%). 

The three mono-epoxides of humulene 1 are naturally occurring, and it is believed that they are in vivo precursors of other bicyclic and tricyclic sesquiterpenes. In vitro experiments have demonstrated that the 1,2- and 4,5-epoxides undergo facile acid-catalysed rearrangement, and it has been shown recently that treatment of a chloroform solution of the 8,9-epoxide with tin(IV) chloride at -60°C for 15 minutes gives a variety of hydrocarbons and one major product (25%), the alcohol 2. 

Lewis Acid Catalysed Rearrangement of Humulene 8,9-Epoxide 

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