Open AccessRadical Chain Reduction via Carbon Dioxide Radical Anion (CO2•–)
Author(s) -
Cecilia M. Hendy,
Gavin C. Smith,
Zihao Xu,
Tianquan Lian,
Nathan T. Jui
Publication year - 2021
Publication title -
journal of the american chemical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 7.115
H-Index - 612
eISSN - 1520-5126
pISSN - 0002-7863
DOI - 10.1021/jacs.1c04427
Subject(s) - chemistry , ketyl , radical ion , radical , photochemistry , alkene , aryl radical , radical initiator , radical disproportionation , electrophile , formate , radical substitution , reactivity (psychology) , hydrogen atom , electron transfer , aryl , ion , organic chemistry , alkyl , catalysis , disproportionation , medicine , polymer , alternative medicine , pathology , polymerization
We developed an effective method for reductive radical formation that utilizes the radical anion of carbon dioxide (CO 2 •- ) as a powerful single electron reductant. Through a polarity matched hydrogen atom transfer (HAT) between an electrophilic radical and a formate salt, CO 2 •- formation occurs as a key element in a new radical chain reaction. Here, radical chain initiation can be performed through photochemical or thermal means, and we illustrate the ability of this approach to accomplish reductive activation of a range of substrate classes. Specifically, we employed this strategy in the intermolecular hydroarylation of unactivated alkenes with (hetero)aryl chlorides/bromides, radical deamination of arylammonium salts, aliphatic ketyl radical formation, and sulfonamide cleavage. We show that the reactivity of CO 2 •- with electron-poor olefins results in either single electron reduction or alkene hydrocarboxylation, where substrate reduction potentials can be utilized to predict reaction outcome.