Search

In this work, an efficient and new Fe3O4@APTES@isatin-SO3Hwas synthesized through immobilization of isatin sulfonic acid on silica modified Fe3O4 nanoparticles. The synthesizedFe3O4@APTES@isatin-SO3Hmagnetic nanoparticles (MNPs) were characterized using the energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), X-ray diffraction (XRD), and thermogravimetric(TGA) analysis. The Fe3O4@APTES@isatin-SO3HMNPs performed efficient catalytic activity as a magnetically recyclable heterogeneous catalyst for one-pot, condensation reaction of 1,2-dicarbonyl compounds and o-phenylen diamines in ethanol at room temperature to afford quinoxaline derivatives.

The electronic sensitivity and adsorption behavior for mercaptan natural gas of a Ca12O12 nanocluster were studied via ab initio computations. To be more specific, to fully grasp the influence of mercaptan molecules on the chemical and electronic features of Ca12O12 nanocluster, some parameters, namely, charge transfer of natural bond orbital, molecular electrostatic potential, binding energies, and frontier molecular orbitals, are computed. The interaction between CH4S molecule and calcium atoms of Ca12O12 nanocluster through the sulfur head is strong. This strong interaction leads to a considerable transfer of charge from CH4S to the nanocluster. After mercaptan adsorption, the existing energy gap between two levels, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of the nanostructure, dropped by 2.21 eV, illustrating that the dissociation process has extensively increased the electrical conductance of nanostructure. This electrical signal can help to detect CH4S molecules. Moreover, it could be concluded that Ca12O12 nanocluster has a short recovery time. In addition, solvent considerably influences the geometry factors and electronic features of CH4S/Ca12O12 complexes, and the interactions between species are significantly weaker in the aqueous medium compared with those in the vacuum.

A simple, highly efficient and green procedure for the condensation of aryl and alkyl 1,2-diamines with α-diketones in the presence of catalytic amount of boron sulfonic acid (BSA) and silica trimethyl borat (STMB) and silica triisopropyl borate (STIPB), as two novel heterogeneous Lewis acid catalysts at room temperature, is described. In this method, we proved that the BrØnsted acidic power of boron sulfonic acid (BSA) is more important than its Lewis acidity. Using this method, quinoxaline derivatives as biologically interesting compounds are produced in high to excellent yields.

Due to the wide importance of β-phosphorylated ketones as key building-blocks in the fabrication of various pharmaceutically active organophosphorus compounds, finding new and truly efficient methods for their preparation from simple, low-cost and ubiquitous feedstock materials within a single click is an interesting subject in organic synthesis. Recently, oxyfunctionalization of carbon–carbon multiple bonds has arisen as a straightforward and versatile tool for the synthesis of complex organic molecules from the simple and easily accessible alkenes/alkynes via a single operation. In this context, oxyphosphorylation of alkenes/alkynes with P(O)–H compounds has attracted considerable attention as a unique procedure for the construction of β-phosphorylated ketones. In this review, we outline the recent advances and developments in this fast-growing research field with particular emphasis on the mechanistic aspects of reaction.

A quantitative structure–retention relation (QSRR) study was conducted on the retention times of 160 pesticides and 25 environmental organic pollutants in wine and grape. The genetic algorithm was used as descriptor selection and model development method. Modeling of the relationship between selected molecular descriptors and retention time was achieved by linear (partial least square; PLS) and nonlinear (kernel PLS: KPLS and Levenberg-Marquardt artificial neural network; L-M ANN) methods. The QSRR models were validated by cross-validation as well as application of the models to predict the retention of external set compounds, which did not have contribution in model development steps. Linear and nonlinear methods resulted in accurate prediction whereas more accurate results were obtained by L-M ANN model. The best model obtained from L-M ANN showed a good R2 value (determination coefficient between observed and predicted values) for all compounds, which was superior to those of other statistical models. This is the first research on the QSRR of the compounds in wine and grape against the retention time using the GA-KPLS and L-M ANN.

In this protocol, 3-(2-carboxybenzoyl)-1-methyl-1H-imidazol-3-ium chloride [Cbmim]Cl and sulfonic acid functionalized pyridinium chloride [pyridine-SO3H]Cl as a new, reusable, and green Brønsted acidic ionic liquid (BAIL) catalyst were synthesized and successfully used for the one-pot ring opening of epoxide with sodium azide (NaN3) in water at room temperature. Epoxides under ring-opening easily with NaN3 in the presence of [Cbmim]Cl and [pyridine-SO3H]Cl to afford the corresponding β-azido alcohols as attractive and interesting materials in drug design and pharmaceutics compounds in high yield with good regioselective under mild reaction conditions.In this protocol, 3-(2-carboxybenzoyl)-1-methyl-1H-imidazol-3-ium chloride [Cbmim]Cl and sulfonic acid functionalized pyridinium chloride [pyridine-SO3H]Cl as a new, reusable, and green Brønsted acidic ionic liquid (BAIL) catalyst were synthesized and successfully used for the one-pot ring opening of epoxide with sodium azide (NaN3) in water at room temperature. Epoxides under ring-opening easily with NaN3 in the presence of [Cbmim]Cl and [pyridine-SO3H]Cl to afford the corresponding β-azido alcohols as attractive and interesting materials in drug design and pharmaceutics compounds in high yield with good regioselective under mild reaction conditions.

The reaction of (E)-3-aryl-2-propenoic acid derivatives with (N-isocyanimino) triphenylphosphorane proceeds smoothly at room temperature to afford the corresponding 2-[(E)-2-aryl-1-ethenyl]-1,3,4-oxadiazole via an intramolecular aza-Wittig reaction in good yields under neutral conditions. The structures of the products were deduced from their IR, 1H NMR, and 13C NMR spectra and mass spectrometry. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:612–616, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20701

Crystals of the title compound, ethyl (Z)-2-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-3-phenyl-2-propenoate, C19H15NO4, Mr = 321.32 are monoclinic, space group P21/n, with a = 6.172(2), b = 8.029(2), c = 32.664(6)A, β = 91.79(3)°, V = 1617.9(7)A3 and Z = 4 at T = 100(2)K. The crystal packing is stabilized by an extensive three-dimensional system of C-H…O/π contacts with some oxygen atoms involved in trifurcated, four-centered interactions.

The use of Smiles rearrangement in Ugi-type couplings with tropolone allows very straightforward multicomponent formation of 2-(N,N-dialkylamino)-2,4,6-cycloheptatrien-1-one derivatives. The Ugi four-component reaction of isocyanides with tropolone (2-hydroxy-2,4,6-cycloheptatrien-1-one), primary amines and aldehydes proceeds smoothly and cleanly under mild conditions to afford 2-(N,N-dialkylamino)-2,4,6-cycloheptatrien-1-one derivatives in fairly good yields.