Polarisation nucleaire induite chimiquement: etude comparative de la decomposition thermique et photochimique de peroxydes d'acyle benzoyle

A comparative CIDNP study of the thermal and photochemical decomposition of acyl benzoyl peroxides PhCO₂O₂CR (R = methyl and isobutyl) has provided an explanation of the effect of the mode of initiation on the course of the decomposition of this class of peroxides and on the product distribution. The observed variations result from an important decrease (from 10^?8 sec to less than 10^?10 sec) in the lifetime of the benzoyloxy radical on changing from thermal to photochemical initiation.