A new tetraazamacrocycle functionalized with four pendant pyridyl groups:: synthesis and crystal structure of the nickel(II) complex of 1,4,7,10-tetrakis(2-pyridylmethyl)-1,4,7,10-tetraazacyclododecane(L), [NiL]2+

The title complex, [NiL](ClO4)(2) was synthesized by the reaction of nickel(II) perchlorate and the new macrocycle ligand, 1,4,7,10-tetrakis(2-pyridylmethyl)-1,4,7,10-tetraazacyclododecane (L) in ethanol solution. The crystal and molecular structure of this complex has been determined by single-crystal X-ray diffraction. The complex consists of [NiL](2+) cation and two perchlorate anions. Within the [NiL](2+) cation, the potential octadentate ligand is using its 4 nitrogen atoms of the macrocycle and 2 pyridine nitrogens to coordinate with the central nickel(II), while the other two pyridine nitrogens remained uncoordinated. The central nickel(II) ion is in a distorted-octahedral coordination environment and in high-spin state. (C) 1997 Elsevier Science Ltd.