A novel dendritic europium complex containing grafted carbazole units as functional peripheries was synthesized and character- ized. The Frster energy transfer from the peripheries of carbazole units to β-diketonate as well as from the ligands to the central Eu(III) ions in the complex was demonstrated. Under the excitation of carbazole units and β-diketonate, characteristic red emission peaks at 612 nm with four shoulders due to the Eu(III) ion transition of 5D0→7FJ (J=0-4) were observed for the complex.
A dinuclear Eu(Ⅲ) complex Eu2(DBM)6TPPD (Hexa(dibenzoyl-methanido)-(N, N, N, N-tetra(2-pyridyl)-1, 4-phenylenediamine)-dieuropium(Ⅲ)) was synthesized by employing DBM (dibenzoylmethane) and TPPD (N, N, N, N-Tetra(2-pyridyl)-1, 4-phenyl-enediamine) as sensitizing ligands for the Eu(Ⅲ) ion and a bridging ligand, respectively. The analysis of the absorption, excitation, and emission spectra of the dinuclear complex along with a comparison with analogous mononuclear complex containing the same β-diketone ligands and 1, 10-phenanthroline (phen) suggests that the dinuclear complex follows the luminescence mechanism of general Ln(Ⅲ) complexes.
A novel heterometallic complex [Na2Cu2Gd2(pdc)4(H2O)14·2H2O] (H3pdc = 1H- pyrazole-3,5-dicarboxylic acid) has been synthesized and characterized by IR spectra, elemental analysis, and single-crystal X-ray analysis. The crystal belongs to the monoclinic system, space group P21/c with a = 7.9521(18), b = 12.251(3), c = 22.293(5) , β = 110.173(5)o, V = 2038.5(8) 3, Mr = 1388.13, Z = 2, F(000) = 1352, Dc = 2.261 g/cm3, μ = 4.380 mm-1, the final R = 0.0409 and wR = 0.0622 for 2453 observed reflections with I > 2σ(I). The structural analysis shows that the NaI, CuII and GdII ions are linked together by two kinds of bridging ligands (pdc3- and H2O) to form a main moiety [Na2Cu2Gd2(pdc)4(H2O)14], which can be regarded as a centrosymmetric dimmer of [NaCuGd(pdc)2(H2O)7]. Many hydrogen bonds exist in the complex to build a 3D supramolecular framework.
Two novel interpenetrated coordination polymers,[Zn(IBA)2]n (1) and {[Cd(IBA)2(H2O)].4H2O}n (2),have been synthesized by using 4-imidazole-benzoic acid (HIBA) as ligand under hydrothermal con-ditions. Complex 1 crystallizes in a chiral space group and has a two-fold interpenetrated 2D network structure with (4,4) topology,while complex 2 is a 3D porous dia network with four nets interpene-trating each other. The SHG activity of 1 and the photoluminescent property of 2 have been investi-gated.
BAI ZhengShuai,CHEN ShuiSheng,ZHANG ZhengHua,CHEN ManSheng,LIU GuangXiang & SUN WeiYin State Key Laboratory of Coordination Chemistry,Institute of Coordination Chemistry,School of Chemistry and Chemical Engineering,Nanjing University,Nanjing 210093,China
Unprecedented synthesis of chiral (aza)crown ethers of calix[4]arene derivatives bearing a carboxyl amide bridge was described. The synthesis proceeds through condensation of the corresponding dinitriles with optically active 1,2-aminoalcohols,and is catalyzed by the ZnCl2 Lewis acid at elevated temperature in a very efficient one-pot process. The cavity of calix[4](aza)crowns can encapsulate methanol molecules by O-H...π interaction,which has been confirmed by X-ray crystal structures and ESI-MS.
ZhengYi Li MingYu Teng JieJie Ma Ji Huang LeYong WangYi Pan
Three complexes obtained by the reaction of Pr(Ⅲ) or Nd(Ⅲ) salts with 5-methyl-2-pyrazinecarboxylic acid(Hmpca) are structurally determined by single-crystal X-ray diffraction.Complex [Pr(mpca-)3(H2O)2]2·6H2O(1) is composed of dinuclear Pr(Ⅲ) units with two metal centers bridged by two anionic mpca-ligands in a κ3O,O':O' bridging mode.Complexes [Pr(mpca-)3]n(2) and [Nd(mpca-)3]n(3) are isostructures,and they consist of polymeric chains based on Ln(Ⅲ) and mpca-ligands.Each pair of adjacent metal centers is linked by three mpca-molecules in a κ3N,O:O bridging mode.
