COPPER(II) COMPLEXES OF MONO-NUCLEATING AND DI-NUCLEATING HEXAAMINES

The potentially hexadentate polyamines N,N,N',N'-tetrakis(2-aminoethyl )ethane-1,2-diamine (L-1) and the octamethylated analogue N,N,N',N'-te trakis(2-dimethylaminoethyl)ethane 1,2-diamine (L-2) have been complex ed with copper(II) and the crystal structures of their complexes deter mined. A trigonal-bipyramidal co-ordination geometry for [Cu(HL1)][ClO 4](3) was found where one aminoethyl arm is not co-ordinated. By contr ast, a dinuclear structure of formula [(H2O)Cu(L-2)Cu(OH)](3+) was det ermined for the N-methylated analogue, where the hexaamine acts as a b ridging ligand between the two square-pyramidal metal centres. Electro nic and EPR spectroscopy are both consistent with these structures bei ng maintained in solution.