Heterogeneous Ru/Re and Rh/Re catalysts, formed in situ from Ru(3)(CO)(12)/Re(2)(CO)(10) and Rh(6)(CO)(16)/Re(2)(CO)(10) respectively, are effective for the liquid phase hydrogenation of cyclohexanecarboxamide (CyCONH(2)) to CyCH(2)NH(2) in up to 95% selectivity without the requirement for ammonia to inhibit secondary and tertiary amine formation. Good amide conversions are noted within the reaction condition regimes 50-100 bar H(2) and >= 150 (Rh) - 160 degrees C (Ru). Variations in Ru:Re and Rh:Re composition result in only minor changes in product selectivity with no evidence of catalyst deactivation at higher levels of Re. In situ HP-FTIR spectroscopy has shown that catalyst genesis occurs via decomposition of the metal carbonyl precursors. Ex situ characterization, using XRD, XPS and EDX-STEM, has provided evidence for the active components of these catalysts containing bimetallic Ru/Re and Rh/Re nanoclusters, the surfaces of which become significantly oxidized after use in amide reduction. Potential mechanistic pathways for amide hydrogenation are discussed, including initial dehydration to nitrile, a pathway potentially specifically accessible to primary amides, and evidence for often postulated imine intermediates. (C) 2010 Elsevier Inc. All rights reserved.