An efficient synthesis of 3-amino-2-arylimidazo[1,2-a]pyridines

An efficient synthesis of 3-amino-2-arylimidazo[1,2-a]pyridines is described via a novel multicomponent reaction between 2-aminopyridines, benzaldehydes and imidazoline-2,4,5-trione under solvent-free conditions.     

Reaction of benzoyl chlorides with Huisgen's zwitterion: synthesis of functionalized 2,5-dihydro-1H-pyrroles and tetrasubstituted furans

The 1:1 intermediate generated by the addition of alkyl(aryl) isocyanides to dimethyl acetylenedicarboxylate is trapped by benzoyl chloride to yield functionalized 2,5-dihydro-1H-pyrroles. The presence of electron-withdrawing groups at the para position of benzoyl chloride leads to tetrasubstituted furans. The structures of these products were confirmed by single-crystal X-ray diffraction studies.     

An ionic 2D inorganic-organic hybrid of tris[((1H-tetrazol-5-yl)methyl)morpholine] dodecatungstophosphate(Ⅴ) pentahydrate:Synthesis X-ray crystal structure and spectroscopic characterizations

<正>A unique ionic hybrid material[C_6H_(12)N_5O]_3[(PO_4)W__(12)O_(36)]·5H_2O has been synthesized from the reaction of((1H-tetrazole-5- yl)methyl)morpholine andα-H_3[(PO_4)W_(12)O_(36)]·21H_2O.It has successfully been characterized by elemental analysis,IR and ~1H NMR spectroscopies,TGA and single-crystal X-ray diffraction method.The title compound is constructed from the three [C_6H_(12)N_5O]~+ cations andα-Keggin[(PO_4)W_(12)O_(36)]~(3-) polyoxoanion.The most remarkable structural feature of this hybrid can be described as two-dimensional inorganic infinite plane-like(2D/∞)[(PO_4)W_(12)O_(36)]~(3-)) which forming via van der Waals interactions along the x axis.     

Computational NQR study of a boron nitride nanocone

Abstract  

The electronic structure of a boron nitride nanocone with 240° disclination, and some properties that derive from this structure, were studied by density-functional theory calculations. In the considered model there are only hexagonal rings, with the apex and mouth of the nanocone saturated by hydrogen atoms. The model was optimized, and then the nuclear quadrupole resonance parameters were calculated at the sites of ¹¹B and ¹⁴N nuclei. The results revealed that the nuclei in the boron nitride nanocone are divided into layers with similar electronic properties. The nuclei at the apex and mouth are very important for the electronic behavior of the nanocone, with ¹¹B playing the major role.     

Potentiometric PVC membrane sensor for the determination of phenylephrine hydrochloride in some pharmaceutical products

A new PVC membrane electrode for the determination of phenylephrine hydrochloride based on the formation of an ionassociation complex of phenylephrine hydrochloride with the phosphotungstate counter anion as an electroactive material dispersed in a PVC matrix is described. The sensor shows a fast, stable, near-Nernstian response for 1.0 × 10^?5 to 1.0 × 10^?1 M phenylephrine hydrochloride at 25 °C over the pH range of 3.5–8.0 with a cationic slope of 58.1 ± 0.6 mV decade^?1. The electrode was successfully used for potentiometric determination of phenylephrine hydrochloride in some pharmaceutical drugs.     

Synthesis of 5-aryl-1,3-dimethyl-6-(alkyl- or aryl-amino) furo [2,3-d]pyrimidine derivatives by reaction between isocyanides and pyridinecarbaldehydes in the presence of 1,3-dimethylbarbituric acid

5-Aryl-6-(alkyl- or aryl-amino)-1,3-dimethylfuro [2,3-d]pyrimidine derivatives were obtained by in situ reaction alkyl or aryl isocyanides and pyridinecarbaldehyde derivatives in the presence of 1,3-dimethylbarbituric acid in dichloromethane without any prior activation or modifications.     

Numerical solution of volterra functional integral equation by using cubic B‐spline scaling functions

In this article, we consider a class of nonlinear functional integral equations which has rather general form and contains a lot of particular cases such as functional equations and nonlinear integral equations of Volterra type. We use a combination of a fixed point method and cubic semiorthogonal B‐spline scaling functions to solve the integral equation numerically. We provide an error analysis for the method which shows that the approximate solution converges to the exact solution. Some numerical results for several test problems are given to confirm the accuracy and the ease of implementation of the method. © 2013 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 30: 699–722, 2014