Recent Advances in Benzimidazole Based NHC‐Metal Complex Catalysed Cross‐Coupling Reactions**
Pravya P. Nair, Anjitha Jayaraj, Chinna Ayya Swamy P
Abstract
Abstract In recent years, there has been a substantial increase in the development of efficient, environmentally compatible and cost‐effective catalysts as a replacement for conventional metal catalysts. Among several catalysts developed, metal‐based N‐Heterocyclic carbene (NHC) catalysts have garnered significant attention due to the unique steric and electronic properties imparted by NHCs, making them suitable for a broad spectrum of chemical transformations. Over a decade, benzimidazole based NHCs have been broadly investigated for the synthesis of metal complexes for a variety of catalytic processes. The interesting properties of benzimidazole scaffolds such as the ease of tailoring its electronic and steric properties via simple synthetic modifications, aids in achieving potential catalysts for cross‐coupling reactions and other hydrofunctional transformations. This review focuses on the synthetic approaches developed over recent years ( 2015 – 2021 ) concerning the structural tuning and modulation of the benzimidazole derived NHC ligands to generate catalytically active metal complexes for cross‐coupling reactions such as Heck, Suzuki, Sonogashira, Kumada and dehydrogenative cross‐coupling reactions.