Complexation of secondary amides to chromium(III): the X-ray structure of a molecule with two modes of monodentate organic amide co-ordination

Abstract

The X-ray crystal structure of the dimer [Cr{H(chba-Et)}(py)₂]₂·2py [H₄(chba-Et)= 1,2-bis(3,5-dichloro-2-hydroxybenzamido) ethane, py = pyridine] establishes, for the first time, the existence of N-co-ordination of an organic amide to Cr^III, the N-atom and carbonyl O-atom of two separate amide groups being co-ordinated to each Cr^III centre [Cr–N 2.030(6) and Cr–O 1.976(5)Å]; the potentially tetra-anionic chelating ligand leads to a variety of co-ordination modes.