Synthesis of water-soluble bis-N,O-chelate nickel(II) complexes based on new ligands - P-pyridyl-containing phospholane oxides

A series of new N,O-hybrid ligands was synthesized by oxidation of pyridyl-substituted phospholanes. These ligands were employed in the first synthesis of water-soluble mononuclear nickel(II) complexes [NiL2(H2O)(2)](BF4)(2) and [NiL2(MeCN)(2)](BF4)(2). Physicochemical properties and crystalline structures of the synthesized compounds were thoroughly studied.