The syntheses, molecular structures, and magnetic properties of a dicopper(I I) complex, [Cu-2(HL1)(2)](CIO4)(2) (1), and its nickel(II) analog, [Ni-2(HL1)(2)](CIO4)(2) (2), of a beta-amino ketoxime ligand (H2L1 4,4,9,9-tetramethyl-, diazadodecane-2,11-dione dioxime) are discussed. The metal centers in out-of-plane oximate bridged clinuclear complexes (11 and 2) display distorted trigonal bipyramidal geometry and form a six-membered M-2(NO)(2) ring oriented in a boat conformation. The two copper(II) centers in 1 interact ferromagnetically giving rise to a triplet-spin ground state whereas the two nickel(II) centers in 2 interact antiferromagnetically to stabilize a singlet-spin state. Vadable temperature magnetic susceptibility measurements establish the presence of a weak ferromagnetic coupling (J = 1 cm(-1)) in 1 and a weak anitiferromagnetic coupling (J = -12 cm(-1)) in 2. The exchange coupling constant derived from B LYP computations in conjunction with broken symmetry spin-projection techni ues for the oximate bridged dinuclear copper(II) complex shows excellent agreement with the corresponding experimental value. A square-planar mononuclear nickel(II) complex of the dioxime ligand, (Ni(H2L1)](CIO4)(2) (3), is reported along with its crystal structure, which reacts with acetonitdle to produce a six-coordinate mononuclear complex, [Ni(L 2)1 (CIO4)2 (4). The ligand (L) in complex 4 is the iminoacyl derivative of oxime, where the coupling of oxime and acetonitrile takes place via a protonassisted pathway. The iminoacylation of H2L1 works with other nitrites like butyronitrile and benzonitrile. Computational studies support a proton-assisted coupling of oxime with nitrile. The critical transition states have been located for the iminoacylation reaction. Complex 4 can be converted back to complex 3 by reacting with sodium acetate in methanol.