Transfer Hydrogenation of N- and O-Containing Heterocycles Including Pyridines with H<sub>3</sub>N–BH<sub>3</sub> Under the Catalysis of the Homogeneous Ruthenium Precatalyst
Tarun Kumar Bhatt, Kishore Natte
Abstract
In this study, we report a transfer hydrogenation protocol that utilizes borane–ammonia (H 3 N–BH 3 ) as the hydrogen source and a commercially available RuCl 3 · x H 2 O precatalyst for the selective aromatic reduction of quinolines, quinoxalines, pyridines, pyrazines, indoles, benzofurans, and furan derivatives to form the corresponding alicyclic heterocycles in good to excellent isolated yields. Applications of this straightforward protocol include the efficient preparation of useful key pharmaceutical intermediates, such as donepezil and flumequine, including a biologically active compound.
Topics & Concepts
ChemistryTransfer hydrogenationCatalysisCombinatorial chemistryRutheniumFuranOrganic chemistryAsymmetric Hydrogenation and CatalysisNanomaterials for catalytic reactionsAmmonia Synthesis and Nitrogen Reduction