Readily prepared resin-bound 2-pyridinethiol and its application for removal of mercury ions

2-Pyridinethiol attached to commercially available monosize chloromethylated polystyrene was used for selective removal of Hg(II) from aqueous solutions containing different amounts of Hg(II) (10?C100?ppm). The adsorption rate was high at the beginning of the reaction and then equilibrium was reached in about 10?min. The maximum Hg(II) adsorption capacity of this novel and stable resin was about 55.94?mg/g of the dry polymer. The Hg(II) adsorption ability increased with increasing pH, in the range where the solubility of the Hg(II) was not affected by pH. More than 95% of the adsorbed Hg(II) was desorbed in 15?min using 1?M HNO₃ as an elution agent. The regeneration of this resin by strong acid was feasible and desorption ratio was very high (up to 96%).     

Highly efficient protection of alcohols and phenols catalysed by tin porphyrin supported on MIL‐101

The catalytic activity of 5,10,15,20‐tetrakis(4‐aminophenyl)porphyrinatotin(IV) trifluoromethanesulfonate, [Sn^IV(TNH₂PP)(OTf)₂], supported on chloromethylated MIL‐101, was investigated in the trimethylsilylation of alcohols and phenols with hexamethyldisilazane (HMDS) and also their tetrahydropyranylation with 3,4‐dihydro‐2H‐pyran. Excellent yields, mild reaction conditions, short reaction times and reusability of the catalyst without significant decrease in its initial activity are noteworthy advantages of this supported catalyst. Copyright © 2015 John Wiley & Sons, Ltd.     

Catalyst‐Free and Green Synthesis of Some Novel Benzamide Derivatives

In the present work, a simple, green, rapid, and catalyst‐free procedure for the synthesis of benzamide derivatives by ring opening of azlactones with diamines such as ethylene diamine and 1,3‐propylenediamine is described. The present method offers several advantages such as short reaction times, easy work‐up, and mild reaction conditions in the absence of catalyst and any toxic solvent and material. In addition, the structure obtained by X‐ray crystallography was compared with the theoretical results obtained by density functional theory using the B3LYP functional and cc‐pVDZ basis sets.     

Oxidation of 2-imidazolines to 2-imidazoles with sodium periodate catalyzed by polystyrene-bound manganese(III) porphyrin

In the present work, the dehydrogenation of 2-substituted imidazolines with sodium periodate in the presence of tetraphenylporphyrinatomanganese(III) chloride supported on polystyrene-bound imidazole, [Mn(TPP)Cl@PSI] is reported. A wide variety of 2-imidazolines were efficiently converted to their corresponding imidazoles by the [Mn(TPP)Cl@PSI]/NaIO₄ catalytic system in a 1:2 CH₃CN/H₂O mixture under agitation with magnetic stirring. Ultrasonic irradiation enhanced the catalytic activity of this catalyst in the oxidation of 2-imidazolines and this led to shorter reaction times and higher product yields. This catalyst could be reused several times without significant loss of its catalytic activity.     

Highly efficient tetrahydropyranylation of alcohols and phenols catalyzed by a new and reusable high-valent vanadium(IV) porphyrin

In the present work, the catalytic activity of high-valent tetraphenylporphyrinatovanadium(IV) trifluoromethanesulfonate, [V^IV(TPP)(OTf)₂], in the tetrahydropyranylation of alcohols and phenols with 3,4-dihydro-2H-pyran (DHP) is reported. This new electron-deficient V(IV) compound was used as a highly efficient catalyst for pyranylation of primary (aliphatic and benzylic), sterically-hindered secondary and tertiary alcohols with DHP. Tetrahydropyranylation of phenols with DHP was also performed to afford the desired THP-ethers. The chemoselectivity of this method was also investigated. The results indicated that primary alcohols are more reactive in the presence of secondary and tertiary alcohols and phenols. This catalyst was reused several times without loss of its activity.     

Synthesis, characterization and investigation of catalytic activity of a highly sulfonated carbon solid acid in the synthesis of dihydropyrimidinones under solvent-free conditions

A highly sulfonated carbon as an efficient, recyclable, nontoxic and green solid acid catalyst was synthesized readily by simultaneous sulfonation, dehydration and carbonization of sucrose C¹²H²²O¹¹ in sulfuric acid and was characterized with Fourier transform infrared spectroscopy (FT-IR), thermal gravimetric and differential thermal gravimetric analysis (TG-DTG), X-ray diffraction (XRD), carbon-hydrogen-nitrogen-sulfur analysis (CHNS), neutralization potentiometric titration and scanning electron microscopy (SEM). This new catalyst was used in one pot three-component condensation reaction of various aromatic aldehydes with ??-ketoester and urea under solvent-free conditions to afford the corresponding dihydropyrimidinones (DHPMs). This catalyst can be reused several times without loss of its activity.     

Chemoselective synthesis of 2-aryloxazines and 2-aryltetrahydropyrimidines using nano-SiO<Subscript>2</Subscript> as a reusable solid acid catalyst under thermal conditions and microwave irradiation

Nano-SiO₂ solid acid efficiently and selectively catalyzed the cyclocondensation reaction of arylnitriles with 3-amino-1-proopanol or 1,3-diaminopropane to afford their respective 2-substituted oxazines and tetrahydropyrimidines in high yields under thermal conditions and microwave irradiation. This methodology works effectively for the selective synthesis of mono-1,3-oxazines and mono-tetrahydropyrimidnes from dinitriles. The catalyst could be recycled and reused several times without a noticeable decrease in its activity.     

Micromorphology of glandular hairs, biological activity and composition of the essential oil of Tanacetum fisherae (Asteraceae-Anthemideae) from Iran

The essential oil was obtained from the aerial flowering parts of Tanacetum fisherae, a new record from Iran, by hydrodistillation and analyzed by GC and GC-MS. Eleven components representing 99.9% of the total oil were identified. 1,8-Cineole (79.9%) was characterized as the principal compound. The essential oil and its main component were tested against nine microbial strains. The result of the bioassays revealed that the oil possess potent antimicrobial property. This may be associated due to the presence of 1,8-cineole in the oil which tested individually and its high activity was observed. Micromorphological studies of hairs by scanning electron microscopy (SEM) exhibited the presence of abundant sessile capitate glandular and medifixed T-shaped eglandular trichomes on the leaves, flowers and achene, giving useful diagnostic characters for identification of this medicinal plant.     

Preparation and Spectral Investigation of Bis[N(2-methyl-phenyl) 4-Nitro-thiobenzamidato] mercury(II), Bis[N(2-methoxy-phenyl) 4-Nitro-thiobenzamidato]mercury(II), and Bis[N(2-chloro-phenyl) 4-Nitro-thiobenzamidato]mercury(II) Complexes

Several preparative routes to bis[N(substituted-phenyl) 4-nitro-thiobenzamidato] mercury(II) complexes are presented, including the reaction of mercury(II) oxide, fluoride, chloride, bromide, cyanide, acetate, and nitrate with N(substituted-phenyl) 4-nitro-thiobenzamide derivatives. ¹ H-NMR, Raman, and IR measurements confirmed the complexation of mercury to sulphur.