Aroylhydrazone derivative as fluorescent sensor for highly selective recognition of Zn2+ ions: syntheses, characterization, crystal structures and spectroscopic properties.

A new Zn(2+) fluorescent chemosensor N'-(3,5-di-tert-butylsalicylidene)-2-hydroxybenzoylhydrazine (H(3)L(1)) and its complexes [Zn(HL(1))C(2)H(5)OH](∞) (1) and [Cu(HL(1))(H(2)O)]CH(3)OH (2) have been synthesized and characterized in terms of their crystal structures, absorption and emission spectra. H(3)L(1) displays high selectivity for Zn(2+) over Na(+), K(+), Mg(2+), Ca(2+) and other transition metal ions in Tris-HCl buffer solution (pH = 7.13, EtOH-H(2)O = 8 : 2 v/v).

Lanthanide radii controlled one-dimensional polymer and dinuclear complexes and their fluorescent properties.

A bi-phosphonate ligand tetraethyl-(2,3,5,6-tetramethyl-1,4-phenylene) bis(methylene)diphosphonate has been designed and synthesized. The bi-phosphonate as a bridging ligand reacts with lanthanide nitrates forming four different types of 1D coordination complexes: ribbon polymer (type I), semi-ribbon polymer (type II), zigzag polymer (type III), and dinuclear-triligand short chain (type IV), which changed according to the decrease of the radius of the lanthanide. They have been characterized by IR spectroscopy, elemental analysis, and X-ray diffraction spectroscopy.

Synthesis and characterization of the ligand based on benzoxazole and its transition metal complexes: DNA-binding and antitumor activity.

A new ligand 2-((2-((benzo[d]oxazol-2-yl)methoxy)phenoxy)methyl)benzoxazole (L) and its four transition metal complexes M(NO(3))(2)L (M=Cu, Co, Ni, Zn), have been synthesized and investigated. The single crystal structures of the complexes show that all of them have similar molecular structure and the ligand exhibits good coplanarity after coordination with the metal ions. Further investigation of DNA binding indicates that both the ligand L and the complexes can bond to DNA by intercalation mode, and the latter possesses much stronger binding affinity.

Fluorescent sensors for Ca(2+) and Pb(2+) based on binaphthyl derivatives.

Two novel binaphthyl compounds have been synthesized for the selective fluorescent recognition of Ca(2+) or Pb(2+). By introducing different terminal groups to the receptor unit, the fluorescence signals of the receptors are significantly changed: 1 is fluorescence enhancement for Ca(2+), 2 is fluorescence quenching for Pb(2+). The binding properties for metal ions were examined by the absorption and fluorescence spectra.

Synthesis, structures, and luminescence properties of lanthanide complexes with structurally related new tetrapodal ligands featuring salicylamide pendant arms.

To explore the relationships between the structures of ligands and their complexes, we have synthesized and characterized a series of lanthanide complexes with two structurally related ligands, 1,1,1,1-tetrakis{[(2'-(2-benzylaminoformyl))phenoxyl]methyl}methane (L(I)) and 1,1,1,1-tetrakis{[(2'-(2-picolyaminoformyl))phenoxyl]methyl}methane (L(II)). A series of zero- to three-dimensional lanthanide coordination complexes have been obtained by changing the substituents on the Pentaerythritol. Our results revealed that, complexes of the L(I) ligand, {Ln(4)L(I)(3)(NO(3))(12).

Design of a semirigid molecule as a selective fluorescent chemosensor for recognition of Cd(II).

A new 8-hydroxyquinoline-based chemosensor possessing a semirigid structure was designed, and its fluorescent sensing behavior toward metalions was investigated. A prominent fluorescence enhancement only for Cd(2+) was found in aqueous methanol solution. The results clearly suggest that the specific semirigid structure could selectively accommodate Cd(2+) according to ionic radius, which would effectively suppress the intramolecular radiationless transitions from the n pi* state to enhance the fluorescence response.

Tuning the self-assembly and luminescence properties of lanthanide coordination polymers by ligand design.

Two new structure-related tripodal ligands featuring salicylamide pendant arms, 1,3,5-tris{[(2'-furfurylaminoformyl)phenoxyl]methyl}-2,4,6-trimethylbenzene (L(I)) and 1,1,1-tris{[(2'-furfurylaminoformyl)phenoxyl]methyl}ethane (L(II)) have been designed and synthesized with the ultimate aim of self-assembling lanthanide polymers with interesting luminescent properties. Among two series of Ln(III) nitrate complexes (Ln = Pr, Nd, Sm, Eu, Gd, Tb or Dy) which have been characterized by elemental analyses, XRD, TGA and IR spectra, three new coordination polymers have been determined by X-ray diffraction analysis. The coordination polymer type {[Ln(NO(3))(3)(L(I))].

Synthesis, structure and spectroscopic properties of rare earth complexes with a new aryl amide 2,2'-bipyridine derivative.

Solid complexes of rare earth nitrates and picrates with a new aryl amide ligand 3.3'-bis(benzylamido)-2,2'-bipyridine (L) were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. The molecular structures of the complex [TbL(2)(NO(3))(3)H(2)O].

Synthesis and spectroscopic properties of lanthanide nitrate complexes with a new amide-based quinoxaline-2,3-dione ligand.

Solid complexes of lanthanide nitrate with 1,4-di(N,N-di-n-butyl-acetamido)-quinoxaline-2,3-dione (L), [Ln(N03)3L.H2O] (Ln=La, Nd, Eu, Gd, Tb, Er), have been prepared and characterized by elemental analysis, IR, UV-vis spectra and conductivity measurements. The fluorescence property of the europium complex in solid state and in MeCN, acetone, AcOEt and THF was studied.

Enhanced fluorescence of 3-(naphthalene-2-ylimino)-1-phenylbutan-1-one-Tb with 1,10-phenanthroline ternary system and its analytical application.

A new Schiff base ligand: 3-(naphthalene-2-ylimino)-1-phenylbutan-1-one (NPB) was synthesized. Its fluorescence intensity with terbium(III) was greatly enhanced by the addition of 1,10-phenanthroline (Phen) in the chloroform solution. The mechanism of fluorescence enhancement was studied.

Study on the new fluorescence enhancement system of Tb -N-(2 - pyridinyl) ketoacetamide-Et3N-Zn and its application.

A sensitive fluorescence enhancement system was developed for the determination of zinc (II). The fluorescence intensity of the Tb- N- (2 - Pyridinyl) ketoacetamide (PKA) system was greatly enhanced by the addition of triethylamine (Et(3)N) and zinc nitrate in the methanol solution. The excitation and emission wavelengths were 329 nm and 546 nm, respectively.