M. Mccann, Michael T. Casey, M. Devereux
Jul 1, 1996
Citations
0
Influential Citations
11
Citations
Journal
Polyhedron
Abstract
Abstract Manganese(II) chloride tetrahydrate reacted with the sodium salt of E -urocanic acid ( E -uroH) in aqueous media giving the manganese(II) complex [Mn( E -uro) 2 (H 2 O) 4 ] in high yield. The X-ray crystal structure of the complex shows two distinct isomers of [Mn( E -uro) 2 (H 2 O) 4 ]. One isomer has the amine nitrogen atom of the imidazole ring lying in a cisoid orientation with respect to the carbon-carbon double bond which bears the pendant carboxylate group, whilst in the other isomer the same nitrogen atom is transoid to the double bond. Both species are centrosymmetric, so that the asymmetric unit comprises two independent half molecules. The geometry at manganese is approximately octahedral, with the metal coordinated by the imine nitrogen atoms from two urocanate anions trans to one another and also by four water molecules. Spectroscopic, magnetic and electrochemical data for the complex are given, together with its catalytic activity towards the disproportionation of H 2 O 2 .