| The coordination polymers, which are formed by linking organic and metal moieties through coordination bonds, are an important field in supramolecular chemistry. Compared with other kinds of supramolecules, coordination polymers exhibit some uniq characteristics: by properly chosing nodes (metal ions) and ligands, one can reasonably design and synthesize coordination supramolecules of special structures and fuctionalities. In addition, the non-bonding interactions shuch as hydrogen bonds,π?πstacking etc. between molecules will have an important influence on the toplonogy of the result supramolecules.In present study, two betaine derivatives 1, 4-bis(4-carboxy-pyridinium)naph- thalene(L1) and 1,4-bis(3-carboxy-pyridinium)naphthalene(L2) have been synthezied. The L1 and L2 exhibit the following significant characteristics: (1) the naked hydrophilic carboxylate groups are good hydrogen bond acceptors; (2) the three aromatic rings in the ligands have strong tendency to formπ?πinteractions and (3) the existence of polar carboxylate groups and positive charged nitrogen atoms enhances the acidity ofα-hydrogen atoms thus enable them grood hydrogen bond donors.The L1 and L2 are subjected to react with various metal salts and twelve coordination polymers, namely [AgL1(ClO4)]n (1), {[Ag3L12(H2O)]·3NO3·4H2O}n (2), {[AgL12]·PF6·3H2O}n (3), {[Ag2L2(H2O)]2·4NO3·4H2O}n (4), {[CuL12]·2NO3·10- H2O}n (5), {[CuL12]·2ClO4·10H2O}n (6), {[CuL22]·2ClO4·2H2O}n (7), {[CuL1Cl2]·HCON(CH3)2}n (8), {[CdL12]·2ClO4·10H2O}n (9), {[ZnL1Cl2]2·3- H2O}n (10), {[CdL1Cl2]·3H2O}n (11), {[Co(H2O)6]·2L2·2- ClO4·6H2O}n (12), have been obtained and characterized by IR spectrum and single crystal X-ray diffraction structure analysis method.The results indicate that (1) silver(I) carboxylates have various coordination modes as shown in 1-4. To our knowledge the chelate coordination mode of carboxylate group to silver(I) centre in complex 3 has not been reported by literature; (2) in copper(II) complexes 5 and 6 NO3- and ClO4- anions are recognized by the coordination rings with C- H... Ohydrogen bonds; (3) all Cl- anions in complexes...
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