Rate constants for the decarboxylation of the <i>t</i>‐butoxicarbonyl radical and concurring radical terminations directly obtained by kinetic ESR

Abstract

Abstract Rate constants of various simultaneous reactions of t ‐butoxicarbonyl and t ‐butyl radicals generated by photolysis of t ‐butylpivalate in n ‐heptane are directly determined by kinetic electron spin resonance. The temperature dependence of the decarboxylation reaction t ‐BuOĊO → t ‐Bu . + CO 2 obeys log ) K /S −1 ( = 13.8−49.0/θ where θ = 2.303 RT /kJ . mol −1 . The self‐ and cross‐termination of the radicals are diffusion limited.