STUDIES ON THE METAL-AMIDE BOND .1. METAL-COMPLEXES OF THE BIS-AMIDE TETRADENTATE LIGAND N,N'-BIS(2'-PYRIDINE-CARBOXAMIDE)-1,2-BENZENE

Complexes of general formula M(bpbH2)Cl2· nH2O, where bpbH2 = N,N′-bis(2′-pyridinecarboxamide)-1,2-benzene and M = Mn (n = 0), Co (n = 1), Co and Ni (n = 2) and Cu (n = 1.5) have been prepared. As well, the complexes Ag(bpbH2)(NO3) and Co(bpbH2)(NCS)2·2.5H2O were isolated. The copper and nickel complexes exhibit clear evidence of neutral amide-N coordination. Several of the metal ions used promote amide deprotonation on coordination, and a series of complexes of formula M(bpb)·H2O (M = Co, Ni, Cu, Zn and Pd) are reported. A planar MIIN4 system is proposed for these complexes. Stereochemistries for the complexes have been proposed utilising microanalyses, magnetic susceptibilities, thermogravimetric analyses and infrared and visible spectral data. © 1979.