NICKEL(II) COMPLEXES OF TETRAAZA MACROCYCLIC LIGANDS BEARING PENDANT DONOR GROUPS .3. THE X-RAY AND CONFORMATIONAL INVESTIGATIONS OF HIGH-SPIN TRANS-2,9-BIS(AMINOMETHYL) AND LOW-SPIN TRANS-2,9-BIS(AMMONIUM 4,8,11-TETRAAZACYCLOTETRADECA-4,11-DIENENICKEL(II) PERCHLORATES

Synthesis and molecular structures of octahedral 2,9-trans-bis-(aminom ethyl)-5,7,7,12 -hexamethyl-1,4,8,11-tetraazacyclo-tetradeca-4,11- die nenickel(II) (2b) complex and of its protonated square-planar form (3b ) are described on the basis of X-ray structural investigations. Compl ex 2b, crystallises in the orthorhombic system, space group Pbca, Z = 4, with cell constants a = 18.468(8), b = 11.137(4), c = 12.110(5) Ang strom. Complex 3b crystallises in the monoclinic system, space group P 2(1)/c, Z = 2, with cell constants a = 9.472(1), b = 13.020(2), c = 13 .138(1) Angstrom; beta = 97.77(1)degrees. The conformations of chelate rings, as the fragments of macrocyclic cations, are defined from thei r calculated puckering parameters.