Recent advances in tridentate iron and cobalt complexes for alkene and alkyne hydrofunctionalizations

The economical and sustainable nature of base metals has recently inspired extensive investigations on the development of iron and cobalt catalysts for alkene and alkyne hydrofunctionalizations. Tridentate ligands are prominent ligands for catalysts development due to their ability to stabilize and modify metal centers, while leaving vacant coordination sites at metal center for substrate bindings. The advantages of tridentate ligands combined with the distinct electronic structures of iron and cobalt have enabled the development of highly efficient hydrofunctionalization of alkenes and alkynes, especially hydrosilylation, hydroboration and their asymmetric versions. Some of tridentate iron and cobalt catalysts have exhibited high activity and selectivity, which can be comparable to or even surpass that of precious metal catalysts. This review covers the recent advances of tridentate Fe and Co complexes catalyzed alkene and alkyne hydrofunctionalizations, highlighting how the structural and electronic modification can regulate the reactivity and selectivity. (C) 2019 Elsevier B.V. All rights reserved.