Two long-chain multidentate ligands： 2,9-di-（n-2＇,5＇,8＇-triazanonyl）-1,10-phenanthroline （L^1） and 2,9-di- （n-4＇,7＇,10＇-triazaundecyl）-1,10-phenanthroline （L^2） were synthesized. The hydrolytic kinetics of 2-hydroxypropyl p-nitrophenyl phosphate （HPNP） catalyzed by the complexes of L^1 or L^2 with La（Ⅲ） or Gd（Ⅲ） have been studied in aqueous solution at （298.2±0.1） K, I=0.10 mol·dm^-3 KNO3 in pH 7.5-9.1, respectively, finding that the catalytic effect of GdL^1 was the best among the four complexes for hydrolysis of HPNP. Its kLnLH-1, kLnLand pKa are 0.047 mol^-1·L·s^-1, 0.000074 mol^-1·L·s^-1 and 8.90, respectively. This paper expounded the studied result with the structure of the ligands and the properties of the metal ions, and deduced the catalysis mechanism.
The title compound, 1,2-bis-（p-nitro-phenylsulfonamido）-4,5-dinitrobenzene, was synthesized and characterized by elemental analysis, IR and 1H NMR. A pale yellow prism crystal of C23H26N8O13S2 （Mr = 686.64） was obtained in DMF solution and determined by single-crystal X-ray diffraction method. It crystallizes in triclinic system, space group P1 with a = 10.346（4）, b = 12.210（5）, c = 12.976（5）A , α = 108.220（8）, β = 99.482（4）, γ = 95.490（4）°, V = 1516.7（10） A^3, Z = 2, Dc = 1.504 g/cm^3, F（000） = 712, μ = 0.254, Mr = 686.64, the final R = 0.0561 and wR = 0.1487. One sulfonamido group of the title compound is deprotoned and forms N（3）=C（13）. The crystal involves N,N-dimethylamine from the decomposition of DMF and the proton is transferred to N,N- dimethylamine. It is a strong proof for the characterization of deprotoned recognition compound by X-ray single-crystal structure.
A Maleamide bridged carbazole receptor was designed and synthesized, the interactions between the receptor and anions, such as Ac-, H2PO4-, OH-, F-, Cl-, Br- and I- in DMSO were investigated by UV-Vis spectroscopy and 1H NMR titration. The results of UV-Vis spectral studies indicate that interactions existed between receptor and anions, which induced remarkable color changes. The 1H NMR titration indicated amide moiety of the receptor was deprontonated first when a small quantity of anions such as Ac-, H2PO4-, F- were added; however, the carbazole N―H was gradually deprontonated upon the addition of anions.
The title compound, N-（1′-H-pyrrol-2′-ylcarbonyl）-5-amino-1,10-phenanthroline, was synthesized by the reaction of a-pyrrolyl carbonyl chloride and 5-amino-1,10-phenanthroline in pyridine. Determined by X-ray structure analysis, it crystallizes in triclinic system, space group P1 with the following crystallographic data： C20H21N5O3, Mr = 379.42, a = 7.8559（4）, b = 9.1681（6）, c = 14.6818（9） A, α= 73.254（10）,β= 88.938（15）, γ= 68.080（10）°, V= 934.66（10） A3, Z = 2, F（000） = 400, Dc = 1.348 g/cm^3 and p = 0.094 mm-1. The final R = 0.0680 and wR = 0.1419 for 2142 observed reflections with I 〉 2σ（/）, and R = 0.1084 and wR = 0.1643 for all reflections. Two aromatic ring planes （pyrrole and phenanthroline rings） are connected by the amide plane. Two different types of intermolecular hydrogen bonds, O-H…N and N-H…O, exist in the crystal. The title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 3-D supramolecule.
A simple colorimetric acetate ion receptor based on 3-methoxysalicylaldehyde-4＇-nitrophenyl-hydrazone was synthesized in an ethanol solution through one step,and characterized by 1H NMR and elemental analyses.Its anion-binding ability was examined by UV-Vis absorption spectroscopy in DMSO（dimethyl sulfoxide）.The result shows that the compound has a high affinity for and a high selectivity toward acetate ions,and also an advantage of ＇naked-eye＇ recognition of color changing from yellow to purple.
Two multidentate ligands 2,9-di[6＇-（2″-hydroxyl-3″-methoxyphenyl）-n-2＇,5＇-diazahexyl]-1,10-phenanthroline（LA）and 2,9-di（6＇-α-phenol-n-2＇,5＇-diazahexyl）-1,10-phenanthroline（LB）were synthesized and fully characterized.Protonation of the ligands and the stability of the complexes of the ligands with divalent metal ions were investigated.The trinuclear metal complexes [Cu（Ⅱ）and Zn（Ⅱ）] of the ligands were studied,as catalysts,for the transphosphorylation of the RNA-model substrate 2-hydroxypropyl-p-nitrophenyl phosphate（HPNP）.The second-order rate constants of HPNP-hydrolysis catalyzed by M3L and M3LH-1 were obtained,which indicated that Zn3LBH-1 was the most efficient catalyst among them.The proposed mechanisms included the activation of the substrate via binding to the metal ions and intramolecular nucleophilic attack by the deprotonated C2-hydroxyl of HPNP.
