A Bottleable Imidazole-Based Radical as a Single Electron Transfer Reagent

J Org Chem. 2021 Jan 1;86(1):1246-1252. doi: 10.1021/acs.joc.0c02465. Epub 2020 Dec 6.

Abstract

Reduction of 1,3-bis(2,6-diisopropylphenyl)-2,4-diphenyl-1H-imidazol-3-ium chloride (1) resulted in the formation of the first structurally characterized imidazole-based radical 2. 2 was established as a single electron transfer reagent by treating it with an acceptor molecule tetracyanoethylene. Moreover, radical 2 was utilized as an organic electron donor in a number of organic transformations such as in activation of an aryl-halide bond, alkene hydrosilylation, and in catalytic reduction of CO2 to methoxyborane, all under ambient temperature and pressure.