SULFURANYL RADICAL STRUCTURE AND REACTIONS OF o-(THIO)BENZOYLOXYL RADICALS FORMED BY THE DECOMPOSITION OF t-BUTYL o-(THIO)-PERBENZOATES STUDIED BY 1H AND 13C CIDNP AND 17O NMR.

Article abstract of DOI:10.1246/bcsj.56.3123

**1H and **1**3C CIDNP signals were observed in the methyl group of o-(methylthio)benzoic acid and the methylene group of 3,1-benzoxathian-4-one during the thermal decomposition of t-butyl o-(methylthio)perbenzoate. The results show that the free 'o-(methylthio)benzoyloxyl radical' itself is better represented as the bridged sulfuranyl radical in which most of the spin density is localized at the sulfur atom rather than in the carboxyl. Thermolysis of t-butyl o-(methylthio)- and o-(phenylthio)perbenzoates-carbonyl-**1**7O was carried out and the oxygen labels were detected by **1**7O NMR spectroscopy. The migration of phenyl group and the peroxomonosulfate oxidation of o-(phenylthio)benzoic acid are also discussed.