Homolytic aromatic substitution by heterocyclic free radicals. Part II. 3-Thienyl radicals

3-Thienyl radicals have been generated by photolysis of 3-iodothiophen, and their reactions with various monosubstituted benzenes as solvents studied. The isomer ratios and the relative rates of 3-thienylation have thus been determined. These values indicate that the 3-thienyl radical has a reactivity which is intermediate between that of 2-thienyl and phenyl radicals. A number of new monosubstituted 3-phenylthiophens are described.