Homolytic aromatic substitution by heterocyclic free radicals. Part III. 3-Benzo[b]thienyl radicals

Abstract

The reactions of 3-benzo[b]thienyl radicals, generated by the photolysis of 3-iodobenzo[b]thiophen, have been studied in a variety of monosubstituted benzenes as solvents. The isomer ratios, and the relative rates of 3-benzo[b]thienylation of anisole, cumene, and methyl benzoate have been determined. These values indicate that the 3-benzo[b]thienyl radical has a reactivity intermediate between those of 2- and 3-thienyl radicals. A number of new monosubstituted 3-phenylbenzo[b]thiophens are described.