CIS-FACIAL COORDINATION OF BIS(PYRID-2-YLMETHYL)AMINE (BPMA) - SYNTHESIS, STRUCTURE AND SPECTRAL BEHAVIOR OF [NI(BPMA)(2)](2+)

Nickel(II) bis-complexes of bis(pyrid-2-ylmethyl)amine (bpma) and bis( benzimidazol-2-yImethyl)amine (bbma)have been isolated. The complexes have been characterised using IR, UV-VIS and H-1 NMR spectral techniqu es. The pink complex [Ni(bpma)(2)](ClO4)(2), crystallises in the ortho rhombic space group Fdd2, with a=22.12(2), b=28.087(2), c=8.857(3)Angs trom, alpha=beta=gamma=90 degrees and Z=8. The nickel(II) atom has a s lightly distorted octahedral structure in which the ligands are cis-fa cially coordinated. The M-N-py bond length in [M(bpma)(2)](2+) [M = Mn (II), Fe(II), NI(II), Cu(U), Zn(II)] complexes decrease and then incre ase with increase in d-orbital population. The ligand held parameters of the new complexes are compared with those of other complexes with N iN6, chromophore. (C) 1998 Elsevier Science Ltd. All rights reserved.