Two new 2D μ-azido, μ-oxalato manganese(II) complexes. Synthesis, structure and magnetic properties

By using the oxalate (ox) and azide bridging ligands, the compounds of formulae [Mn2(N3)2(ox)(4-OHpy)2]n (1) (4-OHpy = 4-hydroxypyridine) and [NaMn(ox)(N3)(H2O)4] (2) can be prepared. The oxalate ligand is generated by the slow decomposition of l-ascorbic acid. The X-ray diffraction analysis reveals two-dimensional systems: in (1), zigzag Mn(II) chains with alternating di-EO-azides (EO = end-on) and di-O,O-pyridone (tautomeric keto-form) bridges are bridged in turn by oxalato anions to form unprecedented two-dimensional honeycomb networks.In (2), zigzag Mn(II) chains with oxalate bridges are bridged in turn by double μ1,1-N3- anions to form also unprecedented 2D honeycomb layers. In the structure of 2, the azide group and water molecules are partially disordered. The magnetic susceptibility measurements indicate bulk antiferromagnetic coupling for 1 and 2.

Unprecedented 2D honeycomb layers of Na[Mn(ox)(N3)(H2O)4] formed through zigzag Mn(II) chains with oxalate bridges and double μ1,1-N3- anions are reported. The overall magnetic behaviour corresponds to a bulk antiferromagnetically coupled system.Figure optionsDownload as PowerPoint slide