Synthesis and characterization of bis(3,6-dicarboxypyridazine)-bis(aqua)manganese(II) dihydrate

Abstract

The crystal structure analyses of copper(II) and iron(II) complexes of 3,6-dicarboxypyridazine (H 2DCP) have shown the role of this ligand to form binuclear complexes. However, the reaction with manganese(II) chloride in an aqueous medium led to the formation of a new mononuclear complex, [Mn(HDCP) 2(H 2O)] · 2H 2O, which has been characterised by X-ray crystallography. The 3,6-dicarboxypyridazine plays the role of a bidentate ligand with a trans coordination mode. The complex has crystallographic C i symmetry. The Mn(II) ion has slightly deformed octahedral geometry and is coordinated to two oxygens of the deprotonated carboxylic acid functions (MnO 2.150 Å), two equivalent nitrogen atoms of the pyridazine rings [MnN 2.298(2) Å)] and two water molecules [MnO(W) 2.160(2) Å].