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The catalytic activity of a Ru complex 1, bearing a fused π‐conjugated imidazo[1,2–a][1,8]naphthyridine‐based mesoionic carbene (MIC) ligand, is examined for the oxidation of primary amines. Complex 1 affords nitrile or imine depending on the nature of the terminal oxidants and solvents used in the reactions. Primary amines are converted to nitriles using NaIO4 in EtOAc/H2O mixture, whereas imines are obtained under O2 balloon pressure in toluene. A variety of nitriles and imines are accessed with high yields and selectivity. A set of control experiments, reaction profiles, and kinetic studies are undertaken to disclose the mechanistic details for nitrile and imine formation. The catalytic reactions illustrate a subtle dependency on the choice of oxidants and solvents in the oxidation of primary amines. [ABSTRACT FROM AUTHOR]

Oxidative deamination of benzyl amines is achieved using a Ni(II)–NHC catalyst with water in aqueous medium. The product is an aldehyde, wherein water acts as a formal oxidant. Hemilabile pyridyl units embedded in the catalyst allow the approach of amine to the metal and promotes nucleophilic water attack on the metal-bound imine. A water-soluble 3d-metal Ni(II) catalyst bearing promoter ligands opens up a new avenue for water-mediated oxidation reactions. [ABSTRACT FROM AUTHOR]