Towards the Definition of the Maximum Allowable Tightness of an Electron Transfer Transition State in the Reactions of Radical Anions and Alkyl Halides

A mechanistic continuum with a sharp changeover zone from electron transfer (ET) to substitution (SUB) reactions has been found in the analysis of the reactions of formyl radical anions with methyl halides (see below). The minimum C – C distance at which the transition state for ET collapses to that of SUB could be defined.