General and selective ruthenium-catalyzed hydrogenation of primary amides to primary amines under mild conditions

The catalytic hydrogenation of amides continues to be one of the most difficult reductive transformations in organic synthesis. Despite significant efforts in past decades, there is no general protocol reported allowing the synthesis of various primary amines from the corresponding primary amides using molecular hydrogen. To perform this challenging reaction, here we report a specific homogeneous ruthenium catalyst based on the methoxy-substituted triphos ligand (Triphos^(p-anisole)). In the presence of this Ru-catalyst system, industrially relevant, functionalized, and structurally diverse aromatic, heterocyclic and aliphatic primary amides including fatty amides have been selectively hydrogenated to produce the corresponding primary amines under comparably mild conditions (typically 115 °C and 10 bar H₂). The resulting amines are valuable compounds with diverse applications in chemistry, medicine and biology as well as in materials and energy technologies.