The free‐radical reaction of tri‐n‐butyltin hydride with disulfides

Abstract

AbstractThe kinetics and absolute rate constants for the free‐radical chain reaction of tri‐n‐butyltin hydride with di‐t‐butyl disulfide have been measured in cyclohexane at 30°. The rate controlling step for chain propagation involves the cleavage of the disulfide bond by an attacking tributyltin radical. The rate constant for this bimolecular homolytic substitution at sulfur is ∼8 × 104 Mole−1 sec−1. Chain termination involves the self‐reaction of two tributyltin radicals.The rate constants for attack of tributyltin radicals on some other disulfides and on elemental sulfur have also been measured. The results are compared with literature data for homolytic substitutions on these compounds by a variety of radicals which have their unpaired electron centered on carbon.