A process is provided for the hydrogenation of imines with hydrogen under elevated pressure in the presence of iridium complexes as catalysts and one or more co-catalysts selected among compounds comprising a carbon-halogen bond. Further provided are novel ligands and metal complexes thereof useful for the catalytic hydrogenation of imines with hydrogen.
The novel ligands are compounds of the formula (VII) or formula (VIII) in the form of racemates, mixtures of stereoisomers or optically pure stereoisomers
wherein the radicals are as defined in the specification.