Solid state coordination chemistry of organodiphosphonates with copper(II) and auxilliary aromatic nitrogen heterocyclic ligands

The hydrothermal reactions of CuSO4 · 5H2O, a phosphonate ligand and an appropriate aromatic nitrogen heterocycle yield a series of materials of the Cu(II)/phosphonate/nitrogen ligand donor family. Two of the materials [Cu(2,2′-bpy)(HO3PCH2CH2CH2PO3H)] (1) and [Cu(4,4′-bpy)(H2O)2(HO3PCH2CH2CH2CH2PO3H)] (2) are two-dimensional, while [{Cu(2,2′-bpy)}2(O3PC6H4PO3)] · 8H2O (3 · 8H2O) is three-dimensional. When 1,3,5-benzenetricarboxylic acid is introduced as a reactant, the one-dimensional material [Cu(2,2′-bpy){OC6H2(CO2H)3}(HOPC6H5)] (4) is isolated. This is an example of an in situ hydrothermal ligand transformation in which the 1,3,5-benzene tricarboxylic acid is hydroxylated to give 1,3,5-benzene tricarboxylic acid-2-hydroxide. Compound 5 [Cu(terpy)(HO3PC6H4PO3H] is molecular.