Synthesis and Structural Characterization of a New Tetranuclear Nickel(II) Sulfato Complex Containing the Anionic Form of Di-2-Pyridyl Ketone Oxime

The preparation and crystal structure of a tetranuclear Ni(II) sulfato cluster containing the anion of di-2-pyridyl ketone oxime, (py) 2CNO −, are reported. Treatment of NiSO 4·6H 2O with one equivalent of (py) 2CNOH and one equivalent of NEt 3 in MeOH leads to the compound [Ni 4{(py) 2CNO} 4(SO 4) 2(MeOH) 4] ( 1) in moderate yield. The metal ions are linked together by two 3.2111 and two 2.1110 (Harris notation) (py) 2CNO − ligands, as well as two 2.1100 SO 4 2− ions to create a rare metallacrown-type (12-MC-4) ring. Strong H-bond intermolecular interactions in 1 lead to the formation of a 1D chain along the 𝑐 axis. Characteristic IR bands are discussed in terms of the known structure of 1.