Synthesis, structure and oxidation of [NiL1]2+[L1= 5-(4-amino-2-azabutyl)-5-methyl-3,7-diazanonane-1,9-diamine]: evidence for rearrangement within the complexed nickel(III) species

Synthesis and properties of cobalt(III) complexes of tripodal ligands containing amide functional groups

“…6,7 Also, a range of different metal complexes with this ligand has been reported and the structure of the nickel() ion, [Ni II (sen)] 2ϩ , has been described. 8 Lions and co-workers 1,2 pointed the way to the rich chemistry and stability of such molecules in the 1950s and 1960s. Since then numerous hexaamine tripodal ligands and their complexes have been reported, 9 including tripods with either 2-pyridylmethyl 10 or 3-aminopropyl 11 arms.…”

Yellow transient forms in the decomposition in acidic solution of the blue–violet nickel(ii) complex of a trifurcated hexamine

“…The structure of [Ni II (L)] 2+ (a in Scheme 1) reflects that determined in the solid state through X-ray diffraction studies. 4 In particular, complex a shows full amine coordination, according to a slightly distorted octahedral geometry. On addition of the first H + ion, one of the three terminal -NH 2 groups is protonated and removed from the coordination sphere, being replaced by a water molecule, to give b.…”