A Study of the Encapsulation of Nickel Phthalocyanine in Molecular Sieve Zeolites of the FAU Type

Nickel(II)phthalocyaninate spectroscopy (NiPc) was synthesized in the supercages of zeolite FAU by the template synthesis method at two different temperatures of 200 and 300°C and characterized by diffuse reflectance spectroscopy, UV-Vis spectroscopy, X-ray powder diffraction, and IR. The results show that the catalyst synthesized at 200°C contains a higher amount of complex as monomeric species encapsulated in the supercages. At elevated temperature, higher amount of the NiPc may be hosted in the mesopores and/or on the external surface of the zeolite as aggregates.     

Facile and Efficient Method for the Synthesis of 14-Substituted-14-H-dibenzo[a,j]xanthenes Catalyzed by Ruthenium Chloride Hydrate as a Homogeneous Catalyst

Synthesis of dibenzoxanthenes through condensation of β-naphthol with various aromatic and aliphatic aldehydes in ethanol as an ecofriendly solvent using Ru^III as catalyst is reported.

A new method for finding the center of gravity of polygons

A direct and easy general method is described for finding the center of gravity of all types of convex and concave polygons such as quadrilaterals, pentagons, hexagons and n-sided polygons.     

A New Trinuclear Zn(II) Complex {[Zn(μ-ONN)(μ<Subscript>2</Subscript>-O)(μ-OO)]<Subscript>2</Subscript>Zn}: Synthesis,Characterization, Thermal Decomposition and Antibacterial Activity

New centrosymmetric trinuclear zinc(II) complex {[Zn(μ-ONN)(μ₂-O)(μ-OO)]₂Zn} has been synthesized by the reaction of a potentially ONN tridentate Schiff base ligand, and N,N-dimethylethylendiamin, with Zn(OAc)₂·2H₂O in methanol, in the refluxed conditions and characterized by elemental analysis, FT-IR and UV–Vis spectroscopy. Single crystal X-ray structure analysis reveals a trinuclear complex {[Zn(μ-ONN)(μ₂-O)(μ-OO)]₂Zn} with zinc(II) ions connected by three different bridges, (μ-ONN) of the Schiff base ligand, μ₂-O and μ-OO of the acetate. The complex is centrosymmetric, with one of the Zn atoms located at the inversion center. While the central Zn(II) ion is six-coordinated, the coordination number of the other Zn(II) ions is five. Finally, the {[Zn(μ-ONN)(μ₂-O)(μ-OO)]₂Zn} complex was thermally decomposed in air at 700 °C resulted in ZnO nano crystalites with the average size of 42 nm. The antibacterial activity of ligand and its zinc(II) complex were tested against gram-positive and gram-negative bacteria. The ligand showed higher activity than its zinc(II) complex.     

Efficient synthesis of 3,4-dihydropyrano[3,2-c]chromenes catalyzed by Ni(II)-functionalized Li<Superscript>+</Superscript>-Montmorillonite in a one-pot fashion under solvent-free conditions

A family of 3,4-dihydropyrano[3,2-c]chromenes were synthesized from 4-hydroxycoumarin and malononitrile via a one-pot reaction under solvent-free conditions at 100 °C catalyzed by Ni@Imine-Li⁺-MMT. This methodology tolerates most of the substrates and has the merits of lower loading of the catalyst, absence of solvents, excellent yields and reusability of the catalyst. A reasonable mechanism is also proposed. This catalytic system can be reused for at least five times with a negligible loss of activity. The prepared catalyst was characterized by using FTIR, TGA, SEM, TEM, uv-DRS, EDX and XRD.     

Buckling and postbuckling of size-dependent cracked microbeams based on a modified couple stress theory

The elastic buckling analysis and the static postbuckling response of the Euler–Bernoulli microbeams containing an open edge crack are studied based on a modified couple stress theory. The cracked section is modeled by a massless elastic rotational spring. This model contains a material length scale parameter and can capture the size effect. The von Kármán nonlinearity is applied to display the postbuckling behavior. Analytical solutions of a critical buckling load and the postbuckling response are presented for simply supported cracked microbeams. This parametric study indicates the effects of the crack location, crack severity, and length scale parameter on the buckling and postbuckling behaviors of cracked microbeams.     

Efficient RuIII-catalyzed synthesis of 9-aryl-9H-xanthene-3,6-diols as precursors to fluorones

Efficient condensation of resorcinol and various aromatic aldehydes in the presence of RuCl₃nH₂O as a homogeneous catalyst under reflux conditions was investigated.It was found that a very simple method afforded good to excellent yields of the desired products.     

Ultrasound assisted, ruthenium-exchanged FAU-Y zeolite catalyzed alkylation of indoles with epoxides under solvent free conditions

Ruthenium-exchanged FAU-Y zeolite (RuY) was used as a recyclable catalyst for regioselective ring-opening of epoxides with indoles under irradiation of sonic waves. It was found that a solvent free process, under the above mentioned conditions provides good yields of the desired 3-alkylated indole derivatives.     

Application of trans-[ZrO(curcumin)2(H2O)]·H2O in coloration of cotton fibers

Research on Chemical Intermediates - A novel six-coordinate complex of Zr(IV) with curcumin ligand was synthesized and characterized by thermogravimetric analysis, elemental analysis and...     

Diastereoselective Ruthenium-Catalyzed Michael Addition of Indoles to Hormone Steroids: An Efficient Route to New Indole Derivatives

Diastereoselective conjugate 1,4-addition of indoles to α,β-unsaturated carbonyl compounds (hormone steroids) using Ru(III) as catalyst is reported. It was found that RuCl₃·nH₂O catalyzes the Michael addition of indoles to hormone steroids, providing new 3-alkylated derivatives in good to excellent yields.