Sodium p-toluenesulfinate/copper(II) acetate in free radical reactions of 5-aryl substituted alkenes

Article abstract of DOI:10.1016/S0040-4020(99)00027-7

p-Toluenesulfonyl radical can be generated from sodium p- toluenesulfinate in aqueous acetic acid or formic acid. Sulfonyl radical mediating reaction of 5-aryl substituted alkenes with sodium p- toluenesulfinate/copper(II) acetate gave p-toluenesulfonylmethyl substituted naphthalene and isoquinoline derivatives. This reaction proceeded much faster in aqueous formic acid than in aqueous acetic acid. The cyclization mode (Ar₂-6 vs Ar₁-5) of the 5-phenyl-1-butyl radical is strongly dependent on the geometry of the tether of the radical intermediate.