Imines are synthesized by the hydrogenation of pyridinecarbonitriles with amines in the presence of a rhodium-loaded catalyst. The resulting imines are stable and may be transiminated and then hydrogenated to form selected secondary amine products or may be hydrolyzed to aldehydes.Further, a very useful class of unsymmetrical secondary amines represented by the formula RCH.sub.2 NHAr (in which R is not aliphatic and Ar is aromatic and not attached to R), which has heretofore been accessible only with some difficulty, can be synthesized by processes herein disclosed utilizing the reductive intermolecular coupling of nitriles and primary aromatic amines.