Structural aspects of metal complexes with some tetradentate schiff bases

The Supramolecular Attitude of Metal–Salophen and Metal–Salen Complexes

“…The five-ring created by ethylendiamine and the central metal ion can adopt a half-chair conformation, an envelope conformation or a slightly distorted form of one of these ( Figure 3) [14]. This means that the possible conformation is either a stepped one (A and B), an umbrella (C) or a slightly distorted form of either [15]. The stepped conformation is chiral, but the umbrella is achiral.…”

{4-Methyl-2-[(2-oxidobenzylidene)amino]phenol-ato(2–)-N,O,O'}(piperidine-N)nickel(II)

“…gafelter, 1959; Calligaris, Nardin & Randaccio, 1972;Bhatia, Bindlish, Saini & Jain, 1981;Kessissoglou, Raptopoulou, Bakalbassis, Terzis & Mrozinski, 1992) and the complexes formed between tridentate N-substituted phenylsalicylaldimines and divalent metal ions such as Cu 2+, Ni 2+, Co 2÷ and Fe 2+ (Kato & Muto, 1988;Kurtz, 1990) have been characterized. In biological systems such as jack-bean urease and some hydrogenases, nickel is in the complexed form (Walsh & Orme-Johnson, • 1987).…”

Chloro[1,1'-diphenyl-3,3'-(ethylenediimino)di-1-butanonato]iron(III), [FeCl(C22H22N2O2)]

“…The metal atom is bonded to the C1-and to the four N20 2 donor atoms of the bzen ligand in a distorted square-pyramidal environment. (6) C(I6)~ID C(15) ~12) C(13) atoms [C(4) 0.477 (5), C(5) -0.329 (5)A] from the coordination plane suggest the conformation as an asymmetric unbrella (Calligaris, Nardin & Randaccio, 1972). The phenyl groups are each planar and have normal bond lengths and angles.…”