Complexes of N-hydroxyethylethylenediamine and its condensation product with acetone

Abstract

The preparation of a number of 1 : 3, 1 : 2, and 1 : 1 complexes of N-hydroxyethylethylenediamine with cobalt(II), nickel(II), copper(II), and zinc(II) salts is described and their structures are discussed. The co-ordinated ligand reacts readily with acetone via condensation with the primary amino-group to give complexes of 7,9,9-trimethyl-3,6,10,13-tetra-azapentadeca-6-en-1,15-diol. These are reported for copper(II) halides and nickel(II) bromide. Attempts to prepare a similar complex with zinc(II) chloride lead to the formation of a 1 : 1 species, Zn(hen + acetone – H₂O)Cl₂. Acetone and N-hydroxyethylethylenediamine also condense readily in the absence of metal ion, but attempts to form complexes of this product with a number of metal salts led only to the formation of previously characterised complexes of N-hydroxyethylethylenediamine.