Poly[(μ(5)-5-carboxylatotetrahydrofuran-2,3,4-tricarboxylic acid)sodium]

The search for the novel metal-organic frameworks (MOFs) materials using tetra­hydro­furan-2,3,4,5-tetra­carboxylic acid (THFTCA) as a versatile multi-carboxyl ligand, lead to the synthesis and the structure determination of the title compound, [Na(H(3)THFTCA)] or [Na(C(8)H(7)O(9))](n), which was obtained by a solution reaction at room temperature. The ligand is mono-deprotonated, coordinating five sodium ions through one furan oxygen atom and six carboxyl oxygen atoms. The sodium ion exhibits a distorted penta­gonal-bipyramidal NaO(7) geometry consisting of seven O atoms derived from five surrounding ligands. Two adjacent pentagonal bipyramids share an O—O edge, forming a dinuclear sodium cluster. Finally, these clusters are effectively linked by the carboxyl groups of THFTCA ligands, forming a firm metal organic framework and O—H⋯O hydrogen bonds contribute to the crystal packing.