Syntheses, structures, and characterizations of four new lead(II) 5-sulfosalicylate complexes with both chelating and bridging neutral ligands.

Four structurally diverse complexes, {[Pb(Hssal)(2,2'-bipy)](4,4'-bipy)0.5}n (1), [Pb2(Hssal)2(2,2'-bipy)2(4,4'-bipy)(H2O)2] (2), [Pb(Hssal)(phen)(4,4'-bipy)0.5]n (3), and [Pb(Hssal)(2,2'-bipy)(bpe)0.5]n (4), have been synthesized and characterized by elemental analyses, IR, thermogravimetric analyses, fluorescent spectra, and single-crystal X-ray analyses, where Hssal2- is doubly deprotonated 5-sulfosalicylate, 2,2'-bipy is 2,2'-bipyridine, phen is 1,10-phenanthroline, 4,4'-bipy is 4,4'-bipyridine, and bpe is trans-1,2-bis(4-pyridyl)ethylene. The structure of complex 1 possesses a one-dimensional ladderlike chain with guest 4,4'-bipy molecules, while the molecular structure of complex 2 is a dimeric species with a coordinating 4,4'-bipy ligand. Complex 3 consists of a one-dimensional ladderlike chain with monodentate 4,4'-bipyridine but somewhat different from that of complex 1. Complex 4 is a two-dimensional layer structure. In 1-4, all 5-sulfosalicylates are doubly deprotonated, and all carboxylate groups of Hssal2- chelate to PbII ions; however, the coordination modes of sulfonyl groups are different: syn-syn bridging in 1, noncoordinating in 2, syn-skew bridging in 3, and one-atom bridging in 4. The noncoordinating mode of sulfonate in PbII complexes containing 5-sulfosalicylate is first reported in this presentation. The 4,4'-bipy ligands act as guest molecules in 1, dimeric linkers in 2, and monodentates in 3. The pi-pi stacking interactions can be observed in complexes 1-3, whereas there is no such interaction in complex 4. The coordination spheres of PbII ions in 1-4 are controlled by three factors: the activity of a lone pair of electrons, weak Pb-O interactions, and pi-pi stacking interactions. The PbII lone pair in 4 is inactive, whereas in 1-3, they are stereochemically active. The thermal stability and fluorescent property of complexes 1-4 are different from those of PbII complexes only containing chelating ligands, [Pb(Hssal)(2,2'-bipy)(DMF)]n (5), and [Pb(Hssal)(2,2'-bipy)(H2O)]n (6), and [Pb(Hssal)(phen)(DMF)]n (7).

Influence of the reaction conditions on the self-assembly of lead(II) 5-sulfosalicylate coordination polymers with chelating amine ligands.

The synthesis and crystal structures of [Pb(Hssal)(2,2'-bipy)(DMF)]n (1), [Pb(Hssal)(2,2'-bipy)(H2O)]n (2), [Pb(Hssal)(phen)(DMF)]n (3), and [Pb3(ssal)2(phen)3]n (4) were reported, where Hssal2- and ssal3- are doubly and fully deprotonated 5-sulfosalicylates, 2,2'-bipy is 2,2'-bipyridine, and phen is 1,10-phenanthroline. Compounds 1-4 were synthesized by the various reaction conditions, such as reaction temperature, molar ratio, and pH, and these structures are formed by infinite chains or layers where Pb(II) ions are linked by Hssal2- or ssal3- bridges. Compound 1, which has a ladderlike chain, was formed in DMF/H2O. Compound 2 with a H2O molecule coordinated to Pb(II) was prepared by a hydrothermal reaction. Compounds 3 and 4 were synthesized in a higher pH compared to compounds 1 and 2, containing the 2,2'-bipy ligand. In 1-3, 5-sulfosalicylates are doubly deprotonated, whereas in 4, 5-sulfosalicylate is fully deprotonated. Coordination modes of Hssal2- and ssal3- ligands in 1-4 are novel and are first reported in this presentation. Although compounds 1 and 3 have the same structural topology, their aromatic-aromatic interactions are significantly different. The coordination spheres of Pb(II) ions in 1 and 3 are holodirected, whereas in 2 and 4, they feature somewhat hemidirected properties with small holes or gaps. Compound 4 exhibits some interesting features that (1) there is not any solvent in the structure, (2) there are extensively aromatic-aromatic stacking interactions among aromatic rings, and (3) there is also a weak interaction between Pb(II) atoms in the trinuclear motif.

A mixed-valence CuII/CuI anion-cation complex: bis[mu-5-sulfosalicylato(3-)]bis[(di-2-pyridylamine)copper(II)] bis[bis(di-2-pyridylamine)copper(I)] dihydrate.

The title compound, [CuII(2)(C7H3O6S)2(C10H9N3)2][CuI(C10H9N3)2]2.2H2O, consists of anionic CuII moieties, cationic CuI species and uncoordinated water molecules. The anionic dimeric unit consists of one crystallographically independent fully deprotonated 5-sulfosalicylate (2-oxido-5-sulfonatobenzoate) anion, a di-2-pyridylamine group and a CuII atom. Each CuII atom is five-coordinate within a square-pyramidal geometry. The anion lies on a special position of -1 site symmetry. In the cationic monomer, the CuI atom adopts tetrahedral geometry. The cations and anions are connected by O-H...O and N-H...O hydrogen bonds.