(C-rac-5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetra-decane-kappa N-4)(nicotinato-O,O ')nickel(II) perchlorate

In the title compound, [Ni(C6H4NO2)(C16H36N4)]ClO4, the macrocyclic unit ad opts a folded conformation, allowing the two carboxyl O atoms to occupy two neighbouring coordination sites and thus form an additional four-membered chelate ring. The less crowded side of the macrocycle (that with the two as ymmetric CDH groups) is directed towards the nicotinate anion and the asymm etric C-CH3 groups are directed away from it. The macrocyclic NH groups nei ghbouring the C-CH3 groups are also directed away from the nicotinate anion , while those NH groups which are near to the geminal methyl groups are dir ected towards the nicotinate anion. Although the complex does not include w ater molecules, three types of hydrogen bond were found, involving NH group s of the macrocyclic ligand, pyridine N atoms and O atoms of the perchlorat e anions.