Electron Transfer in Organic Reactions

Abstract

Most organic bond-forming reactions can be described as nucleophile-electrophile combinations. For many of these reactions there have been discussions as to whether the bond formation occurs together with the electron transfer or whether electron transfer and bond formation take place in separate steps. This discussion is reviewed and it is shown how to distinguish between the different processes based on kinetic analysis.

The NO3Radical-Mediated Liquid Phase Nitration of Phenols with Nitrogen Dioxide

“…In fact, a CTC has been proposed as an intermediate in some electrophilic substitution reactions in order to account for some features of the photochemical aromatic nitration (38) and was confirmed by N-15-CIDNP experiments (39). The original concepts (40) have been recently reviewed in the light of distinguishing if electron transfer and bond formation take place in separate steps (41).…”

A Radical Mechanism for Frustrated Lewis Pair Reactivity

“…Quinones are well known to be electron acceptors with the formation of chargetransfer complexes. 43,44 Control experiments revealed that no reaction was observed on treatment of Mes 3 P with pO 2 C 6 Cl 4 in C 6 H 5 Cl. Moreover, the UV-visible ).…”

H-Coupled Electron Transfer in Alkane C−H Activations with Halogen Electrophiles

“…Isobutane Reactions with the Allyl Cation. There are a number of indications that hydrogen-transfer reactions of carbocations with alkanes are similar to H-abstractions with radicals. ,, In many so-called “hydride transfer reactions” − R−H + Alk + → [R···H···Alk] + → R + + H−Alk, the transferred hydrogen formally does not carry a negative charge due to the higher electronegativity of carbon . The VB approach for the simplest model [H 3 C−H−CH 3 ] + system clearly shows that the hydrogen being transferred indeed has some radical character.…”