Acta Crystallographica Section B

Structural Science

Volume 57, Part 3 (June 2001)

research papers

Acta Cryst. (2001). B57, 317-328 [ doi:10.1107/S0108768100020280 ]

Hydrated metal complexes of N-(6-amino-3,4-dihydro-3-methyl-5-nitroso-4-oxopyrimidin-2-yl)glycinate: interplay of molecular, molecular-electronic and supramolecular structures

J. N. Low, J. M. Moreno Sánchez, P. Arranz Mascarós, M. L. Godino Salido, R. López Garzon, J. Cobo Domingo and C. Glidewell

Abstract: The title anion, (C₇H₈N₅O₄)^-, L^-, forms hydrated metal complexes with a range of metal ions M⁺ and M²⁺. Lithium and manganese(II) form finite molecular aggregates [Li(L)(H₂O)₃] (1) and [Mn(L)₂(H₂O)₄].6H₂O (4) in which the molecular aggregates are linked into three-dimensional frameworks by extensive hydrogen bonding. The sodium and potassium derivatives, [Na₂(L)₂(H₂O)₃] (2) and [K(L)(H₂O)] (3) both form organic-inorganic hybrid sheets in which metal-oxygen ribbons are linked by strips containing only organic ligands: these sheets are linked by hydrogen bonds into three-dimensional frameworks. In (2) the metal-oxygen ribbon is built from pairs of edge-shared trigonal bipyramids linked by water molecules, while in (3) it consists of a continuous chain of vertex-sharing octahedra. The nitroso group in the anion acts as an [eta] ¹ ligand towards Na⁺ and as an [eta] ² ligand towards K⁺. In all cases the anion L^- shows the same unusual pattern of interatomic distances as the neutral parent LH.

Keywords: hydrated; supramolecular structures.