Catalytic applications of transition metal complexes with NHC ligands

Abstract

Transition metal complexes bearing protic-NHC (N-heterocyclic carbene) ligands have attracted significant attention due to their unique structural and electronic properties. However, their catalytic potential remains relatively underexplored. This work presents and discusses the catalytic applications of ruthenium complexes featuring protic-NHC ligands. Specifically, we report the synthesis and characterization of pincer ligand-based ruthenium complexes incorporating halide derivatives, iodo and chloro as the sixth coordinating ligand. The Ru (II) CNN complexes have been characterized by LC-MS, multinuclear NMR spectroscopy (1H, 13C), and SCXRD. Spectroscopic investigations, including UV-Visible and fluorescence spectroscopy, were performed, along with electrochemical studies using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The catalytic activity of CNN-based metal complexes towards amine double-dehydrogenation, hydration of nitriles, and water oxidation catalysis has been explored.