Cobalt(II) frameworks of 3,3 '-bipyridyl-5,5 '-dicarboxylate(bpdc(2-)). X-ray crystal structures of [Co(bpdc)(H2O2)(2)](n) and {[Co(bpdc)(H2O4]center dot 2H(2)O}(n)

Sodium 3,3'-bipyridyl-5,5'-dicarboxylate (Na 2 bpdc) reacts with cobalt(ll) chloride under hydrothermal conditions to give the guest-free two-dimensional framework [Co(bpdc)(H 2 O) 2 ] n 1 and at ambient temperature to generate the one-dimensional polymer {[Co(bpdc)(H 2 O) 4 ].2H 2 O} n 2. In 1 the bpdc 2- ligand is tetradentate, coordinating through the pyridyl nitrogens and two of the carboxylate oxygen atoms, in 2 solely the nitrogen atoms of this ligand bind to cobalt.