The reaction of the CCl3O2˙ radical with indoles

Abstract

In its reaction with indoles the CCl₃O₂˙ radical adds predominantly to the C(2)–C(3) double bond. Only a minor fraction accounts for one-electron oxidation. The 3-adduct undergoes rapid cleavage along the peroxidic bond while several rearrangement paths are indicated for the 2-adduct. In addition, the latter was found to break down into an indolyl radical cation in the presence of protons. The C(3) carbon adduct eventually reduces oxygen to O₂^–˙. The major end products formed from indoles unsubstituted at the 3-position are indoxylic compounds while substantial amounts of open amides are found among the end products derived from 3-methylindoles.