Mechanistic Aspects of Hydrosilane/Potassium tert-Butoxide (HSiR(3)/KO(t)Bu)-Mediated Reactions

[Image: see text] The hydrosilane/potassium tert-butoxide reagent system has attracted significant attention over the last 5 years since the discovery of its ability to silylate heteroarene C–H bonds. Numerous useful HSiR(3)/KO(t)Bu-mediated transformations are now known, including silylation of sp, sp(2), and sp(3) C–H bonds, reductive cleavage of C–O, C–S, and C–N bonds, reduction of polycyclic arenes, and hydrosilylation and polymerization of styrenes. This mini-review surveys the rich diversity of reaction mechanisms, both ionic and free radical and including hydride transfer, H atom transfer, and electron transfer, that have been uncovered during recent studies on the HSiR(3)/KO(t)Bu reagent system. Several mechanistic phenomena that remain to be explained are also highlighted.