Silica Supported Perchloric Acid： A Convenient and Environmentally Friendly Catalyst for the One-pot Multicomponent Synthesis of ,β-Acetamido Ketones

A modified Dakin-West one-pot, four-component condensation of an aryl aldehyde, aryl ketone, acetyl chloride and acetonitrile in the presence of silica supported perchloric acid as an active, inexpensive, recoverable and recyclable catalyst is reported for the synthesis of β-acetamido ketones under mechanical stirring and ultrasonic irradiation conditions. This system has advantages of short reaction times, good to excellent yields and the ability to carry out the large scale reactions. The use of ultrasound increases the rate of reactions compared with reactions at reflux conditions.

Silica-supported Perchloric Acid Catalyzed One-pot Synthesis of 1,4-Dihydropyridines

An environmentally friendly and highly efficient procedure for the preparation of 1,4-dihydropyridines by the reaction between a,β-unsaturated aldehydes, aromatic amines and β-keto esters in the presence of silica supported perchloric acid is described.

Poly-N-benzylaniline prepared in perchloric acid——a new soluble semiconducting polymer

Chemical or electrochemical oxidation of N-benzylaniline in perehloric acid solution yields a highly colored polymer——poly-N-benzylaniline (PBAn).The polymer has good solubility in a num- ber of organic solvents in either acid or base form.At room temperature,conductivity measurements on pressed pellets of the acid form PBAn give a conductivity of 9.3×10^(-6) S·cm^(-1).The soluble polymer was analyzed using a variety of common experimental techniques including UV-vis,IR,NMR,ESR spectroscopy,elemental analysis and electrochemieal analysis.All experimental results showed that PBAn has a structure similar to polyaniline with the elimination of some benzyl groups.

Nuclear magnetic resonance spectroscopy is highly sensitive for lipid-soluble metabolites

Although the water-soluble metabolite profile of human mesenchymal stem cells is known, the lipid profile still needs further investigation. In this study, methanol-chloroform was used to extract lipid-soluble metabolites and perchloric acid was used to extract water-soluble metabolites. Fur- thermore, a dual phase extraction method using methanol-chloroform and water was used to obtain both water and lipid fractions simultaneously. All metabolite extractions were analyzed on a 9.4T high-resolution nuclear magnetic resonance spectrometer. Metabolite resonance peaks were as- signed in the acquired spectra according to the chemical shift, and the extraction efficiency of dif- ferent methods was compared. Results showed that in the spectra of water-soluble extracts, major metabolites comprised low molecular weight metabolites, including lactate, acetic acid, fatty acids, threonine, glutamic acid, creatine, choline and its derivatives, while in the spectra of lipid-soluble extracts, most metabolites were assigned to fatty acids. Among the different extraction procedures, perchloric acid was more efficient in extracting water-soluble metabolites and methanol-chloroform was efficient in extracting organic components compared with the dual phase extraction method. Nuclear magnetic resonance spectroscopy showed that as low as 0.7 mg organic yield was enough to obtain clear resonance peaks, while about 6.0 mg water-soluble yield was needed to obtain rela- tively favorable spectral lines. These results show that the efficiency of extracting water and lipid fractions is higher using perchloric acid and methanol-chloroform compared with dual phase ex- traction and that nuclear magnetic resonance spectroscopy is highly sensitive for analyzing lipid-soluble extracts.

Determination of Dimethylallylamine by Titration in Nonaqueous Solvent

The content of dimethylallylamine was determined using glacial acetic acid as solvent, acetic-formic mixture as an anhydrite, perchloric acid-glacial acetic acid as titrant, and 1% crystal violet in acetic acid as indicator in the presence of methylamine and dimethylamine The influences of inert constituents and water on the titration were investigated, and a complete analytical method was determined. The results showed that the determination error of total amines increased with water increasing, while the effect of water on the determination of dimethylallylamine was little when the amount of water was within 5%, the relative error was generally within 1%, and that the end-point was acutely when about 10% chloroform was added. Compared with gas chromatography, this method is simple, convenient and accurate.

Regeneration and reuse of anode graphite from spent lithium-ion batteries with low greenhouse gas (GHG) emissions

Regenerating spent graphite(SG)from retired lithium-ion batteries(LIBs)can effectively avoid resource waste.However,the technology is challenged by the impurity content and energy consumption.In this study,micro-expanded graphite(MEG)was synthesized by one-step oxidation method using waste LIBs anode graphite as material and perchloric acid as intercalation and oxidant agent.Then,its performance as a LIBs anode material were investigated as well as the greenhouse gas(GHG)emissions of the whole process were calculated.Perchloric acid was successfully embedded in the SG during the reaction,which effectively removed the impurities in the graphite.Defects introduced during intercalation and delamination,such as nanopores and intercrystalline cracks.Both provide additional space for Li ions during charging and discharging,thereby promoting capacity enhancement.The prepared MEG expresses a rate capability as high as 340.32 m Ah/g at a current density of 0.1 C and still retains 81.73%of the capacity after 100 cycles at a current density of 1 C.Additionally,the GHG emissions of the synthesis process of this article and other literatures are compared.The results demonstrated that perchloric acid treatment process provides a low-carbon,time-and energy-saving approach for regenerated SG as battery grade material.