Exploration of Regulation of Alcohol Dehydrogenation Reaction of Dibenzimidazole-Based Ruthenium Complexes

This work demonstrates the synthesis of a series of Ru(II) complexes with dibenzimidazole-based ligands and investigates the spatial relationship between ligand structure and complexes. It explores the effect of substituent changes on the N-Ru-N bond angle of the complexes, as well as the distance from the Ru center to the aryl group, and utilizes these complexes to catalyze benzyl alcohol dehydrogenation in toluene. It was found that the ligand [Ru]-complex with a spatial configuration of electron donating groups had a larger N-Ru-N bond angle and higher catalytic performance at the ruthenium center, with a yield of 91.2%. Moreover, its distance from the umbrella hydrocarbon was sufficient to allow for the attack of the reactant molecules and the occurrence of catalytic reactions. The reaction mechanism was subsequently derived. This manuscript is expected to provide assistance and inspiration for the development of high-performance catalysts for alcohol dehydrogenation reactions. © 2025 by the authors.