Structures of the complexes of CdCl2 with the aliphatic triamines bis(2-aminoethyl)amine, bis(3-aminopropyl)amine, and 2-aminoethyl-(3-aminopropyl)amine: influence of aliphatic chain length on molecular association

Abstract

Single-crystal X-ray analyses of the complexes obtained by reaction of CdCl₂ with the title amines, hereafter denoted by baa, bpa, and apa respectively, have shown different molecular conformations for the three compounds: Cd(baa)Cl₂ is polymeric while Cd(bpa)Cl₂ and Cd(apa)Cl₂ are dimeric with cis and trans configurations respectively. Co-ordination around cadmium is octahedral with one chlorine atom acting as a bridge, which is linear in the polymer and bent in the dimers. Nuclear magnetic resonance spectra are not indicative of the presence in solution of a multistructural model for the complexes.