Structural characterization of manganese and iron complexes with methylated derivatives of bis(2-pyridylmethyl)-1,2-ethanediamine reveals unanticipated conformational flexibility.

Iron and manganese complexes with derivatives of bis(2-pyridylmethyl)-1,2-ethanediamine (bispicen) have previously been found to be efficient catalysts for hydrocarbon oxygenation. Methylation can potentially impact the conformation of the ligand around the metal center and the electronic character of the bound metal ion; each of these, in turn, impacts reactivity. Reported are mononuclear manganese(II) and iron(II) compounds with bispicen and five increasingly methylated derivatives.