A novel one-dimensional tubular cadmium(II) coordination polymer based on 5-(carboxyl­atometh­oxy)benzene-1,3-di­carboxyl­ate containing 4-amino­pyridinium ions

A novel anionic tubular Cd^II coordination polymer based on the 5-(carboxyl­atometh­oxy)benzene-1,3-di­carboxyl­ate ligand and containing 4-amino­pyridinium cations had been synthesized under hydro­thermal conditions. In the solid state, the 4-amino­pyridinium cation props up the structure through hydrogen bonds to the O-atom acceptors of ligands and solvent water mol­ecules.

A well-resolved cyclic water tetra­mer in a dinuclear Cu^II coordination complex based on 1,2-bis­(pyridin-3-yl­oxy)ethane and capped by pyridine-2,6-di­carb­oxy­lic acid

Two five-coordinated aqua­copper(II) centres chelated to pyridine-2,6-di­carboxyl­ate terminal ligands are bridged by a 1,2-bis­(pyridin-3-yl­oxy)ethane spacer. The structure includes a well-resolved cyclic water tetra­mer, which acts as a subunit to form a larger aggregate.