The imino pyridine Schiff base cobalt(II) and nickel(II) complexes (
C1 and
C2) and their functionalised γ-Fe
3O
4 counterparts (
Fe3O4@C1 and
Fe3O4@C2) were synthesised and characterised using IR, elemental analysis,
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The imino pyridine Schiff base cobalt(II) and nickel(II) complexes (
C1 and
C2) and their functionalised γ-Fe
3O
4 counterparts (
Fe3O4@C1 and
Fe3O4@C2) were synthesised and characterised using IR, elemental analysis, and ESI-MS for
C1 and
C2, and single crystal X-ray diffraction for
C1, while the functionalised materials
Fe3O4@C1 and
Fe3O4@C2 were characterized using IR, XRD, SEM, TEM, EDS, ICP-OES, XPS and TGA. Complexes
C1,
C2 and the functionalised materials
Fe3O4@C1 and
Fe3O4@C2 were tested as catalysts for the selective transfer hydrogenation of cinnamaldehyde and all four pre-catalysts showed excellent catalytic activity. Complexes
C1 and
C2 acted as homogeneous catalysts with high selectivity towards the formation of hydrocinnamaldehyde (88.7% and 92.6%, respectively) while
Fe3O4@C1 and
Fe3O4@C2 acted as heterogeneous catalysts with high selectivity towards cinnamyl alcohol (89.7% and 87.7%, respectively). Through in silico studies of the adsorption energies, we were able to account for the different products formed using the homogeneous and the heterogeneous catalysts which we attribute to the preferred interaction of the C=C moiety in the substrate with the Ni centre in
C2 (−0.79 eV) rather than the C=O (−0.58 eV).
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