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α-Fe2O3 grains grafted onto TiO2/carbon nanofibers (CNFs) for use as anode materials in lithium-ion batteries have been successfully fabricated by electrospinning and vapor-solid reaction (VSR). Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and N2 adsorption-desorption isotherms reveal that the ultrafine α-Fe2O3 nanoparticles were formed on the TiO2/CNFs and have uniform dispersion along the fiber direction. The VSR approach could retard nucleation, thus making TiO2/CNFs with small Fe2O3 grains grafting (approximately 5 nm in diameter). The TiO2/CNFs are capable of buffering the large volume variation of α-Fe2O3 during cycling and preventing electrode pulverization and aggregation, as well as providing sufficiently large interstitial space within the crystallographic structure to host Li ions. The electrochemical properties of the composite electrodes were tested by galvanostatic cycling at both constant and variable current rates. The composite delivers both good rate capability under an uprated current density of 1000 mA g−1 and especially enhanced cycle stability (∼600 mA h g−1 after 200 cycles at a current density of 1000 mA g−1). The super electrochemical performance is attributed to a synergetic effect between α-Fe2O3 and TiO2-CNFs as well as the three- dimensional (3D) network, which contributes to greatly enhanced diffusion kinetics and structural stability for lithium-ion batteries. This VSR approach can be extended to other hierarchical metal oxide nanostructures for favorable applications in electrochemical devices.

An efficient, eco-friendly and sustainable method for the tandem oxidative amidation of alcohols with amines has been reported. Using heteropolyanion-based ionic liquids as the catalyst and tert-butyl hydroperoxide as the oxidant, this amidation reaction is operationally straightforward and provides a series of primary, secondary and tertiary amides derivatives in moderate to good yields. Solvent-free media, microwave-promoted conditions and reusability of catalysts are the main highlights. Further, the proposed bifunctional catalysis mechanistic pathway has been briefly investigated in this report.

A series of 2,3-dihydroquinazoline-4(1H)-one derivatives have been synthesized via one-pot three-component reaction using isatoic anhydrides, amines and aldehydes (or ketones) catalyzed by heteropolyanion-based ionic liquids under microwave-promoted conditions. The practical protocol was found to tolerate a wide range of substrates with different functional groups. Moderate to excellent yields, solvent-free media and operational simplicity are the main highlights. Furthermore, the catalyst can be recovered and reused without evident loss of reactivity. This method provides a green and much improved protocol over the existing methods.

An efficient strategy for the discovery of kinase inhibitors by a combination of diversity-oriented synthesis and selective screening is described. Initially, a set of 10 compounds representing a 10-scaffold library of diversity-oriented pyrimidine-containing compounds were tested against 40 enzymes selected from the kinase family, which resulted in the discovery of a selective p38α inhibitor. In the next step, the subset from the scaffold with the active was screened against the pairing enzyme (p38α). Eventually, the most potent compounds were measured for IC50 (42.7 nM) and tested in MM1S and U266 cells by observing the complete suppression of the phosphorylation of p38α at submicromolar concentrations. Therefore, a series of novel tricyclic pyrimido[4,5-b][1,4]benzothiazepines with potent inhibitory activity against p38α kinase in vitro and in cellular assays were discovered utilizing this methodology. This strategy may be applicable for the drug discovery of a superfamily of targets using a large library of compounds.

A simple and efficient procedure for the synthesis of amides directly from aldehydes and amines catalyzed by heteropolyanion-based ionic liquids under solvent-free conditions has been reported. The practical protocol was found to tolerate a wide range of substrates with different functional groups. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. The proposed dual-catalysis mechanistic pathway was briefly investigated. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this oxidative amidation.

We are presenting a sensor for hydrogen peroxide (H2O2) that is based on the use of a heterostructure composed of Pt nanoparticles (NPs) and carbon nanofibers (CNFs). High-density Pt NPs were homogeneously loaded onto a three-dimensional nanostructured CNF matrix and then deposited in a glassy carbon electrode (GCE). The resulting sensor synergizes the advantages of the conducting CNFs and the nanoparticle catalyst. The porous structure of the CNFs also favor the high-density immobilization of the NPs and the diffusion of water-soluble molecules, and thus assists the rapid catalytic oxidation of H2O2. If operated at a working voltage of −0.2 V (vs. Ag/AgCl), the modified GCE exhibits a linear response to H2O2 in the 5 μM to 15 mM concentration range (total analytical range: 5 μM to 100 mM), with a detection limit of 1.7 μM (at a signal-to-noise ratio of 3). The modified GCE is not interfered by species such as uric acid and glucose. Its good stability, high selectivity and good reproducibility make this electrode a valuable tool for inexpensive amperometric sensing of H2O2.

A simple and efficient procedure for the synthesis of amides directly from unactivated esters and amines catalyzed by heteropolyanion-based ionic liquids under microwave-promoted and solvent-free conditions has been reported. The practical protocol was found to be compatible with different structurally diverse substrates. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this amidation.

An efficient and green route for the synthesis of dihydropyrimidinones via microwave-assisted Biginelli reaction catalyzed by 3 mol% of heteropolyanion-based ionic liquids under solvent-free conditions has been reported. The practical reaction was found to be compatible with different structurally diverse substrates. Good to excellent yields, short reaction times, and operational simplicity are the main highlights of this protocol. Moreover, the heteropolyanion-based ionic liquids were easily reusable for this Biginelli reaction.

An environmentally benign and highly efficient protocol for the transamidation of non-activated carboxamides with amines using heteropolyanion-based ionic liquids as catalysts under microwave-assisted and solvent-free conditions has been developed. As evaluated by the reactions of a structurally diverse set of amides and amines, the scope and utility of the transamidation proved to be quite general. Operational simplicity, solvent-free media, the potential reusability of catalysts and wide functional group tolerance are attractive features. This method provides a much improved protocol over the existing methods.

The copper-catalyzed formation of C–O bonds by oxidative coupling of benzylic alcohols with ethers was realized in open air. A series of α-acyloxy ethers were obtained in good yields with aqueous tert-butyl hydroperoxide as the oxidant.

A facile and efficient protocol for the construction of CO bonds by oxidative coupling of alcohols with ethers has been realized in the absence of transition metals. The reaction was performed with a catalytic amount of n-Bu4NI and aqueous TBHP as an oxidant. A series of α-acyloxy ethers were obtained in good yields.

An eco-benign and highly efficient route for N-acylation of amines has been developed by treating amines with corresponding carboxylic acids in the presence of 2 mol % of heteropolyanion-based ionic liquids as catalysts under solvent-free conditions. This practical reaction could tolerate a wide range of substrates. Thus, various N-acylation products including N-acyl α-amino acid derivatives were obtained in moderate to excellent yields at 70 °C to 120 °C. Moreover, recycling studies revealed that heteropolyanion-based ionic liquids were easily reusable for this N-acylation. This method provides a green and much improved protocol over the existing methods.

A practical and efficient construction of C–O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various α-acyloxy ethers were obtained with up to 93% isolated yield.

We have developed a 3-dimensional (3-D) electrochemical sensor for highly sensitive detection of hydrogen peroxide (H2O2). Porous 3-D carbon nanofibers (CNFs), prepared by electrospinning, served as scaffold on a glassy carbon electrode. The 3-D CNFs were functionalized with platinum nanoparticles (Pt-NPs) by in-situ gas-phase decomposition of platinum salts at high temperature. The Pt-NPs act as an electrocatalyst for the decomposition of H2O2. TEM revealed that large amounts of Pt-NPs are deposited in the electrospun CNFs electrode even without using any stabilizer or reducing reagent. The sensor was investigated by cyclic voltammetry and amperometry and displays a good response to H2O2 with a linear range between 10 μM and 15 mM (R = 0.9994), a low detection limit (3.4 μM at a signal-to-noise ratio of 3), and a response time of 3 s. The sensor shows excellent stability and selectivity.

The underlying principle of drug design in this paper is that the maximum retention of the functional groups that exist in the marketed drug would provide a higher probability for comparable safety while the conformational changes in the newly created analogs should not constitute a significant structural variation to adversely affect biological activity. Four individual isomers of backbone re-organized ezetimibe analogs were designed and synthesized. Their effects on the cholesterol levels in rat serum were evaluated by a high-cholesterol and high-fat diet feeding experiment. All the new analogs showed significant effect in lowering the levels of total cholesterol in serum.

A simple and efficient procedure for the synthesis of amides directly from unactivated esters and amines catalyzed by heteropolyanion-based ionic liquids under microwave-promoted and solvent-free conditions has been reported. The practical protocol was found to be compatible with different structurally diverse substrates. Moderate to excellent yields, solvent-free media, and operational simplicity are the main highlights. Furthermore, the heteropolyanion-based ionic liquids were easily reusable for this amidation.

The method developed not only preserves the operational simplicity of Biginellis one-pot condensation but also provides both compatibility with various functional groups and good to excellent yields of the dihydropyrimidinones within short reaction times.

The environmentally friendly and operationally simple transamidation reaction is performed with primary, secondary, and tertiary amides as well as phthalimide with a variety of primary and secondary amines.

The copper-catalyzed formation of C–O bonds by oxidative coupling of benzylic alcohols with ethers was realized in open air. A series of α-acyloxy ethers were obtained in good yields with aqueous tert-butyl hydroperoxide as the oxidant.

A practical and efficient construction of C-O bonds via oxidative cross-coupling reaction of aldehydes and ethers has been realized under open air. When 2 mol% copper was used as the catalyst, various α-acyloxy ethers were obtained with up to 93% isolated yield.

This N-acylation of amines uses a heteropolyanion-based ionic liquid as catalyst under solvent-free conditions.

2,2,6,6-Tetramethylpiperidine Phosphorous trichloride (S)-H8-BINOL (S)-1(8,9,10,11,12,13,14,15)-Octahydro-3,5-diox-4-phosphacyclohepta[2,1-a;3,4a′]dinaphthalen4-yl)-2,2,6,6-Tetramethylpiperdine Tris(dibenzylideneacetone)dipalladium Di-tert-butyldiaziridinone (4S,5S)1-3-Di-tert-butyl-4-phenyl-5-vinylimadazolidin-2-one Keywords: Palladium catalyst; Asymmetric alicyclic diamination; Homoallylic diamination; Phenyl butene; Vicinal diamines; Mechanism Terminal olefins; Waste disposal

The scope of a sulfur monoxide extrusion reaction of pyrimido[4,5-b][1,4]benzothiazepines leading to pyrimido[5,4-c]isoquinolines was investigated. Thus, selective oxidation followed by nucleophilic displacement of the oxidized side chain sulfur group and subsequent extrusion reaction of sulfur monoxide in the ring, which can be conducted in a two-step sequence or in a one-pot procedure, produced novel pyrimido[5,4-c]isoquinolines, a class of compounds with potential biological and pharmaceutical applications. [reaction: see text].