Cumyl derivatives , nucleophilic

Results such as these have led to recurring discussions about the extent of stabihzation of the transition state for heterolytic cleavage at tertiary carbon by nucleophilic assistance from solvent. The difficulty lies in reconciling studies that suggest that there is a small dependence of obsd (s ) for solvolysis of tert-butyl chloride,and some cumyl derivatives, on solvent nucleophilicity with other work that shows there is no detectable stabilization of the transition state for these reactions by interaction with the strongly nucleophilic azide and hydroxide ions, and the strong neutral nucleophile propanethiol. ... 

Some chemical additives can induce ion-radical formation and direct the reaction along the ion-radical route. The effect was discovered and studied in cases of nucleophilic substitutions of cumene derivatives (Kornblum 1975, 1982). Cumyl radicals are formed at the first step of substitution irrespective of whether a dissociative or homolytic cleavage takes place as a result of electron transfer to the cumene derivatives (Zheng et al. 1999). 

---