Hydrothermal treatment of FeCl2. 4H(2)O (or FeCl3. 6H(2)O) and piperazine (or 2-methylpiperazine) with H3PO4 and H2C2O4 in H2O yields two organically templated compounds. The 3-D frameworks are constructed from Fe-II-O (or Fe-III-O) polyhedra and two different ligands, phosphate and oxalate, both coordinated to the iron atoms. The structure of the Fe-III compound is shown.