Synthesis, structures, and properties of lead(II) and cobalt(II) metal-organic frameworks based on a flexible benzophenone-2,4′-dicarboxylic acid (H2bpdc)

Two new coordination polymers, [Pb(bpdc)](n) (1) and [Co(bpdc)(phen)](n) (2) [H(2)bpdc = benzophenone-2,4'-dicarboxylic acid, phen = 1,10-phenanthroline], have been synthesized and structurally characterized. Hydrogen bonding and pi center dot center dot center dot pi stacking extend 1 and 2 into 3-D supramolecular architectures, where 1 exhibits a 3-D framework with 1-D hairpin-like helicates based on Pb-O covalent bonds and 2 displays a 3-D network with 1-D zipper-like chains based on Co-O and Co-N covalent bonds. The FT-IR spectra, PXRD and TG analyses are discussed for 1 and 2. Fluorescence spectra and luminescent lifetime are studied for 1.