Crystal structure of poly[(4-amino­pyridine-κN)(N,N-di­methyl­formamide-κO)(μ3-pyridine-3,5-di­carboxyl­ato-κ3 N:O 3:O 5)copper(II)]

The title compound, [Cu(C7H3NO4)(C5H6N2)(C3H7NO] n , is an amino-function-alized chiral metal-organic framework with (10,3)-a topology. It has been constructed via the assembly of the achiral triconnected pyridine-3,5-di-carboxyl-ate (3,5-PDC) building block and a triconnected Cu(II) atom. Each Cu(II) ion is coordinated by two O atoms and one N atom, respectively, of three crystallographically independent 3,5-PDC ligands. The square-pyramidal (CuN2O3) coordination geometry of the Cu(II) ion is completed by an N atom of a terminal 4-amino-pyridine (4-APY) ligand and the O atom of a terminal N,N-di-methyl-formamide (DMF) ligand to give a triconnected 'T'-shaped secondary building unit, which becomes trigonal in the resulting (10,3)-a topology. In the three-dimensional structure, weak N-H⋯O hydrogen bonds are observed in which the donor N-H groups are provided by the 4-APY ligands and the acceptor O atoms are provided by the non-coordinating carboxylate O atoms of the 3,5-PDC ligands.