Synthesis,characterization, and crystal structure of Ni(II) and Cu(II) complexes with N-furoyl-N′,N′-diethylthiourea: antifungal activity

The complexes cis-bis(N-furoyl-N′,N′-diethylthioureato-k ²O,S)nickel(II) and cis-bis(N-furoyl-N′,N′-diethylthioureato-k ²O,S)copper(II) were prepared by the reaction of metal acetate with the corresponding acylthiourea derivative. The complexes were characterized by IR, ¹H-NMR, ¹³C-NMR, and single-crystal X-ray diffraction. Both complexes show two furoylthiourea ligands bonded to metal to form a four-coordinate complex with square-planar geometry. The antifungal activity of the prepared complexes was studied against the phytopathogenic fungi Botrytis cinerea and Colletotrichum gloeosporioides, responsible for important plant diseases.     

Catalytic asymmetric synthesis of descurainin via 1,3-dipolar cycloaddition of a carbonyl ylide using Rh2(R-TCPTTL)4

A catalytic asymmetric synthesis of descurainin has been achieved by incorporating an enantioselective 1,3-dipolar cycloaddition, a stereoselective alkene hydrogenation, an oxidation with Fremy’s salt and a regioselective demethylation with NbCl₅ as the key step. The 1,3-dipolar cycloaddition of a carbonyl ylide derived from tert-butyl 2-diazo-5-formyl-3-oxopetanoate with 4-hydroxy-3-methoxyphenylacetylene in the presence of dirhodium(II) tetrakis[N-tetrachlorophthaloyl-(R)-tert-leucinate], Rh₂(R-TCPTTL)₄, provided an 8-oxabicyclo[3.2.1]octane skeleton in 95% ee.     

Electropolymerized surface ion imprinting films on a gold nanoparticles/single-wall carbon nanotube nanohybrids modified glassy carbon electrode for electrochemical detection of trace mercury(II) in water

Electrochemical detection of Hg(II) using a electropolymerized ion imprinting poly(2-mercaptobenzothiazole) films at the surface of gold nanoparticles/single-walled carbon nanotube nanohybrids modified glassy carbon electrode (PMBT/AuNPs/SWCNTs/GCE) is described for the first time. The Hg(II)-imprinted PMBT/AuNPs/SWCNTs/GCE sensor exhibits larger binding to functionalized capacity, larger affinity, faster binding kinetics and higher selectivity to template Hg(II). The differential pulse anodic stripping voltammetry (DPASV) response of the Hg(II)-imprinted PMBT/AuNPs/SWCNTs/GCE sensor to Hg(II) is ca. 3.7- and 10.5-fold higher than that at the non-imprinted PMBT/AuNPs/SWCNTs/GCE and the imprinted PMBT/AuNPs/GCE, respectively, and the detection limit for Hg(II) is 0.08 nM (S/N = 3, which is well below the guideline value given by the World Health Organization) and a sensitivity of 0.749 μA nM⁻¹ was obtained. Excellent wide linear range (0.4–96.0 nM) and good repeatability (relative standard deviation of 2.6%) were obtained for Hg(II). The interference experiments show that Ag(I), Pb(II), Cd(II), Zn(II) and Cu(II) had little or no influence on the Hg(II) signal. These values, particularly the high sensitivity and excellent selectivity in contrast to the values reported previously in the area of electrochemical Hg(II) detection, demonstrate the analytical performance of the Hg(II)-imprinted PMBT/AuNPs/SWCNTs/GCE toward Hg(II) is superior to the existing electrodes and could be used for efficient determination of Hg(II) in natural water samples.     

Synthesen und Eigenschaften von Bis(perfluoralkyl)zink‐Verbindungen

Syntheses and Properties of Bis(perfluoroalkyl)zinc Compounds The conditions for the syntheses of bis(perfluoroalkyl)zinc compounds Zn(R_f)₂ · 2 D (R_f = C₂F₅, n‐C₃F₇, i‐C₃F₇, n‐C₄F₉, n‐C₆F₁₃, n‐C₇F₁₅, and n‐C₈F₁₇; D = CH₃CN, tetrahydrofurane, dimethylsulfoxide) are described. Mass spectra, thermal decompositions, ¹⁹F‐ and ¹³C‐NMR spectra are discussed.     

Differential Pulse Polarographic Study of Ternary Complexes of Copper (Ii) With Pyruvate and Some Amino Acids

Abstract

The ternary complexes of copper (II) with glycine, alanine, aspartate or glutamate as primary ligand and pyruvate as secondary ligand have been investigated using differential pulse polarography. the reversible diffusion controlled reduction of the complexed ion reveals two mixed complexes to be formed with stoichiometries 1:1:1 and 1:2:1. Their overall formation constants in a sodium perchlorate supporting electrolyte have been calculated at μ =0.1 and 25°C.     

A Six-Coordinate Picrate Nickel(II) Complex Based on the V-Shaped Ligand 1,3-Bis (1-Benzylbenzimidazol-2-yl)-2-Thiapropane: Synthesis,Crystal Structure,Biological Activities

Abstract

A six-coordinate picrate nickel(II) complex based on the V-shaped ligand 1,3-bis(1-benzylbenzimidazol-2-yl)-2-thiapropane (L), with the composition [Ni(L)₂](pic)₂, has been synthesized and characterized systematically. The crystal structure of the Ni(II) complex is a six-coordinated octahedron, which is considerably close to ideal octahedral geometry with N₄S₂ donors of the two ligands. Biological activities of compounds were investigated using electronic absorption spectroscopy, fluorescence spectroscopy, and viscosity measurements. The results suggested that both ligand L and Ni(II) complex bind to DNA in an intercalative binding mode, and DNA-binding affinity of the Ni(II) complex is stronger than that of ligand L.

[Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional figures.]     

Spectrophotometric Determination of Hydrazine

Abstract

A simple sensitive and selective method is described for the determination of trace amounts of hydrazine. The method is based on the reduction of nitrate to nitrite. Hydrazine in ammoniacal condition is used as reducing agent with copper(II) as catalyst. The nitrite prepared is determined based on the diazo coupling reaction between p‐nitroaniline and N‐(1‐naphthyl)ethylenediammine dihydrochloride(NEDA). The method obeys Beer's law in the concentration range of 0–15 µg of hydrazine in a sample volume of 10 ml at 545 nm and the colour is stable for 3 h. The molar absorptivity is calculated to be 3.83×10⁴ l/mol/cm with a correlation coefficient of 0.999. The relative standard deviation is 1.8% (n=10) at 12 µg of hydrazine. Interferences due to foreign ions have been studied and the method has been applied for the determination of hydrazine in boiler feed water.     

Synthesen und Kristallstrukturen neuer Bromoferrate(III), Chloro‐ und Aquachloroferrate(III) mit tetraedrischer und oktaedrischer Eisenkoordination,darunter zwei Neutralkomplexe von Eisen(II) und ‐(III)

Halogeno Metallates of Transition Elements with Cations of Nitrogen‐containing Heterocyclic Bases. VIII Syntheses and Crystal Structures of Novel Bromoferrates(III), Chloro‐, and Aquachloroferrates(III) with Tetrahedral and Octahedral Iron Coordination, among them two Neutral Complexes of Iron(II) and (III) (dmpipzH₂)[Fe^IIIBr₄]₂ ( 1 ), (trienH₂)[Fe^IIIBr₄]Br ( 2 ), (dmpipzH₂)[Fe^IIICl₄]Cl ( 3 ), (dmpipzH₂)₂[Fe^III(H₂O)₂Cl₄][Fe^IIICl₄]Cl₂ ( 4 ), and (trienH₂)[Fe^III(H₂O)₃Cl₃]Cl₂ ( 5 ) crystallize from aqueous mineralic acid solutions of iron(II) halide and the organic bases (1,4‐dimethylpiperazine or triethylenediammine) in the presence of atmospheric oxygen whereas (dmpipzH₂)[FeCl₄(H₂O)₆]Cl₂ ( 6 ) was obtained under the exclusion of air. 1 , 2 , and 3 contain the known tetrahedral halogeno complexes, 4 contains a novel octahedral iron(III) complex, and in 6 a neutral binuclear iron(II) complex has been found which has not been described before. The crystal structures and the hydrogen bridging systems of the complexes are described.     

Synthesis, Structure and DFT Investigation into a Copper(II) Compound Consisting of 4,7-diphenyl-1,10-phentheanthroline

1 INTRODUCTION terested in the unique effects associated with substituents at 4- and 7-positions of the phenan- The coordination chemistry of 1,l0-phenanthroline throline ring. Thus, when phenyl groups are present, and its derivatives has captured the attention of che- the absorptivities of the CT transitions are increased mists for years. The reports on biological importance[1~4], markedly due to the extension of the dipole moment supramolecular chemistry[5], electronic spectra[6], conne…