1-(Alkylsulfinyl- and -alkylsulfonyl)-2-(F-alkyl)ethynes − Applications in Cycloaddition Reactions and Synthesis of Aromatic Derivatives

Syntheses and cycloaddition reactions of 1-(alkylsulfinyl- and -alkylsulfonyl)-2-(F-alkyl)ethynes are described. These alkynes are strong dienophiles and produce the corresponding F-alkylated sulfinyl- and sulfonylbenzenes in two high-yielding steps. When treated under basic conditions, the (F-alkyl)cyclohexadienyl adducts were converted into a mixture of the same aromatic compounds and the corresponding α-defluorinated derivatives, by way of a competitive oxidation/(HF) elimination on the deprotonated intermediates.