Crystal structure and physico-chemical properties of hepta-coordinate isomorphic cobalt(II) and nickel(II) complexes of 1-allylimidazole

Nitrate 1-allylimidazole coordination compounds of the general formula [ML(3)(NO(3))(2)], where M is cobalt(II) or nickel(II) and L is 1-allylimidazole, have been obtained. The compounds were characterized by single crystal X-ray diffraction, elemental analysis, IR, RR and VIS spectral evidence and by magnetic measurements. Both compounds are isomorphic and crystallize in the monoclinic system, space group C2/c, with Z = 4. There are two bidentate nitrato groups and three 1-allylimidazole molecules in the coordination sphere of the metals. One of these 1-allylimdazole molecules is disordered and situated along a twofold axis with half-occupancy (occupation factor, G = 0.5). (C) 2000 Elsevier Science B.V. All rights reserved.