Development of New Aerobic Methodologies for Generating Radicals from Aryl Boronic Acids

Abstract

Over the last few decades, the development of new and simple protocols of radical generation has changed the misconceptions or the historical perception that all transformation involving radicals are uncontrollable and unselective which today have helped scientists to get more insight on the factors affecting selectivity in free radical reactions. With these developments, the application of radical chemistry for organic transformation has always increased and much useful chemistry has been developed over the years using radical intermediates. For instance, in organic chemistry, aryl radical serves as versatile intermediate to obtain industrially important organic derivatives. Despite their potential success with broad range of applications, they also suffer from certain drawbacks such as (1) the utilization of very expensive and toxic reagents (Sn and Si) for coupling of phenyl halides; (2) the use of stoichiometric amount of oxidants and reductants (K2S2O8 and Mn(OAc)3) for phenyl carboxylic acids and phenyl boronic acids are considered to be harsh and undesirable; (3) similarly the use of SmI2 and Ag-salts for generation of aryl radicals from phenyl halides, phenyl diazonium salts, phenyl boronic acids, and phenyl carboxylic acids are considered to be energy-intensive reagents newline