Ruthenium-catalyzed acceptorless dehydrogenative coupling of o-aminobenzyl alcohols with ketones to quinolines in the presence of carbonate salt

A ruthenium complex bearing a functional 2,2'-bibenzimidazole ligand [(p-cymene)Ru(BiBzImH(2))Cl][Cl] was designed, synthesized and found to be a general and highly efficient catalyst for the synthesis of quinolines via acceptorless dehydrogenative coupling of o-aminobenzyl alcohols with ketones in the presence of carbonate salt. It was confirmed that NH units in the ligand are crucial for catalytic activity. The application of this catalytic system for the scale-gram synthesis of biologically active molecular was also undertaken. Notably, this research exhibits new potential of metal-ligand bifuctional catalysts for acceptorless dehydrogenative reactions. (C) 2020 Elsevier Inc. All rights reserved.

Automated summary

A ruthenium complex with a functional ligand was synthesized and found to be an efficient catalyst for the synthesis of quinolines. The NH units in the ligand were crucial for the catalytic activity. This research demonstrates the potential of metal-ligand bifunctional catalysts for acceptorless dehydrogenative reactions.