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Today, tremendous attention has been devoted to a new coronavirus, SARS-CoV-2 (2019-nCoV), due to severe effects on the global public in all over the world. Rapid and accurate diagnosis of 2019-nCoV are important for early treatment and cutting off epidemic transmission. In this regard, laboratory detection protocols, such as polymerase chain reaction (PCR) and computed tomography (CT) examination, have been utilized broadly for 2019-nCoV detection. Recently, nano-based methods for 2019-nCoV diagnoses are rapidly expanding and declaring comparable results with PCR and CT. In this review, recent advances in nano-based techniques have been highlighted and compared briefly with PCR and CT as well-known methods for 2019-nCoV detection.

Copper (II) oxide nanorods and nanospheres were prepared and their structural, morphological, and electronic properties were investigated by X-ray diffraction analysis, X-ray absorption near edge structure, scanning electron microscope and transmission electron microscope.CuO nanoparticles efficiently catalyzes azide-alkyne 1,3-dipolar cycloaddition (CuAAC) reaction producing corresponding 1,2,3-triazole derivatives in excellent yields without use of any additives. The advantages of present protocol are mild reaction conditions, reusability of the catalyst, and applicability to a wide range of substrates.

The (NH4)12[Mo36(NO)4O108(H2O)16]·30.84H2O ({Mo36}) catalyst has been synthesized and successfully employed in the selective oxidation of various sulfides to sulfoxides with urea hydrogen peroxide as oxidant under mild reaction conditions with 84–99 % conversion and 58–99 % selectivity, with active functional groups such as the hydroxy group and C=C bonds tolerated in the oxidation. The {Mo36} catalyst showed high catalytic activity for a high substrate/catalyst ratio (up to 30000:1) and is recyclable.

The reactions of FeCl3·6H2O and 2-(2′-hydroxyphenyl)-2-thiazoline as a bidentate O-N donor thiazoline ligand (thoz) afford a five-coordinate FeIII complex [Fe(thoz)2Cl] with a distorted square pyramidal configuration. Complex [Fe(thoz)2Cl] was isolated as air-stable crystalline solids and fully characterized, including by single-crystal X-ray structure analysis. Complex [Fe(thoz)2Cl] shows very efficient reactivity in the oxidation of sulfides to their corresponding sulfoxides using urea hydrogen peroxide (UHP) as the oxidant at room temperature in air.

We report a simple methodology for the stabilization of Cu2O nanoparticles of size 10–30 nm on the polar pore surface of the polyoxomolybdate (NH4)12[Mo36(NO)4O108(H2O)16] ({Mo36}). For the first time, a Cu2O@{Mo36} composite has been utilized as a recyclable catalyst for the Huisgen 1,3-dipolar cycloaddition reaction of terminal alkynes, aryl/alkyl halides and NaN3 for the synthesis of 1,2,3-triazoles.

A new aromatic diamine, 2,3-bis(4-(4-amino-2-(trifluoromethyl) phenoxy)phenyl)naphtho[2,3-f]quinoxaline-7,12-dione, was synthesized and fully characterized by using FTIR, 1H and 13C NMR, DEPT technique, and elemental analysis. A series of novel fluorescent anthraquinone-quinoxaline containing polyamides (PAs) with inherent viscosities of 0.39–0.62 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many polar aprotic organic solvents and could be solution-cast into tough and flexible films. The PAs exhibited glass transition temperatures (Tg)s between 230 and 323°C, and 10% weight loss temperatures in the range of 362–433°C in N2. All of the PAs have fluorescence emission in solution and in solid state with maxima around 452–510 nm and with the quantum yields in the range of 6–17%. Also, cyclic voltammetry (CV) method was used to study the electrochemical oxidation behavior of these polymers at the surface of a modified multiwalled carbon nanotube (MWCNT)s glassy electrode. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A polymeric manganese(II) complex with the general formula [Mn(O2CCH2NH2CH2CO2)2(H2O)2]n from reaction of iminodiacetatic acid and manganese(II) perchlorate under nitrogen in water, was synthesized and characterized. The structure of the complex was determined using single-crystal X-ray diffraction, elemental analysis, IR and UV-vis spectra. This complex exhibited excellent catalytic activity and selectivity for oxidation of various alcohols and sulfides to the corresponding aldehydes/ketone and sulfoxides using urea hydrogen peroxide and oxone (2KHSO5·KHSO4·K2SO4), respectively, as oxidants under air at room temperature. The easy preparation, mild reaction conditions, high yields of the products, short reaction time, no over-oxidation products, high selectivity and inexpensive system make this catalytic system a useful method for oxidizing various alcohols and sulfides. Copyright © 2011 John Wiley & Sons, Ltd.

The solvent-free O-acylation of some alcohols with benzoyl chloride was carried out to the corresponding benzoylated products in good to excellent yields by the mediation of a catalytic amount (5 mol%) of the commercially available and inexpensive zinc oxide in short reaction times. This methodology represents an eco-friendly and simple catalytic alternative for benzoylation of primary, secondary, tertiary, and benzylic alcohols with ZnO. This catalytic system was homogeneous because of high solubility of zinc oxide in the reaction medium. Findings showed that ZnO was dissolved in hydrochloric acid, created in situ, after a few minutes. Although, others argued on the catalytic role of solid phase zinc oxide under a heterogeneous condition, it is not surprising to emphasize on the catalytic function of Zn2+ in the benzoylation of alcohols under homogeneous reaction conditions. Zinc oxide served as pre-catalyst to form Zn2+, as the catalytically active species.

Epoxides are important materials in the production of fine chemicals. Selective oxidation of alkenes to epoxides remains a challenge in synthetic chemistry. There has been considerable progress in tungsten-catalyzed epoxidation of alkenes in recent years. This review highlights the use of monomeric and dimeric oxido–peroxido tungsten(VI) complexes as catalysts or oxidants in homogeneous or heterogeneous catalytic systems for epoxidation of olefins.

For the first time, iron oxide on carbon aerogel, amine functionalized carbon nanotube, black carbon and carboxylic acid functionalized carbon nanotube in the presence of H2O2 was reported as an efficient and stable catalyst for the selective oxidation of sulfides and alcohols. The catalysts were characterized by scanning electron microscopy, energy-dispersive spectroscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and atomic absorption spectroscopy. In the next step, catalytic reactivity toward sulfide to sulfoxide and alcohol to aldehyde/ketone oxidation in the presence of H2O2 was studied and discussed.

Readily prepared copper(II) immobilized on layered double hydroxide has been found to effectively catalyse the 1,3-dipolar cycloaddition (CuAAC) of a variety terminal alkynes and benzyl azides generated in situ from sodium azide and benzyl halides furnishing the corresponding 1,2,3-triazoles in excellent yields. The advantages of the protocol are short reaction time, mild reaction conditions, reusability of the catalyst and applicability to a wide range of substrates.

V/TiO2 nanoparticles were synthesized by a one-pot solution combustion method using ammonium metavanadate and titanyl nitrate as a source of vanadium and titanium, respectively. Atomic absorption spectroscopy (AAS), FT-IR, X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to characterize the physicochemical properties of this compound. This compound shows efficient catalytic reactivity for epoxidation of olefins and oxidation of alcohols in the presence of H2O2 as an oxidant.

The catalyst generated in situ from Pd(OAc)2 and LIG shows good activity in the Suzuki reaction of aryl halides (I) with arylboronic acids (II).

Novel imidazolium salts, precursors of N-heterocyclic carbenes, are prepared and applied as ligands in the title reactions.

The present new method provides internal E-isomers exclusively, except the reaction with acrylonitrile (IV) gives a mixture of stereoisomers.

A reaction pathway is proposed with zinc oxide serving as pre-catalyst to form Zn2+ as the catalytically active species.

New unsymmetrical diamine monomer containing triaryl pyridine pendent group, 2,4-diaminophenyl [4-(2, 6-diphenyl-4-pyridyl) phenyl]ether, was synthesized via aromatic substitution reaction of 1-chloro-2,4-dinitrobenzene with 4-(2,6-diphenyl-4-pyridyl) phenol, followed by Pd/C-catalyzed hydrazine reduction. Five Polyamides (PA) were prepared by the phosphorylation polycondensation of different dicarboxylic diacids with the diamine. Inherent viscosities of PAs were in the range 0.51–0.59 g/dL indicating formation of medium molecular weight polymers. The weight and number average molecular weights of a PA, (PA-d), determined by GPC were 6944 g/mol and 17,369 g/mol, respectively. PAs exhibited glass-transition temperatures (Tg) in the range 140–235°C. These polymers, essentially amorphous, were soluble in polar aprotic solvents such as DMF, NMP, DMAc, DMSO, pyridine, m-cresol, and THF. The initial decomposition temperatures (Ti) of PAs, determined by TGA in air, were in the range 300–380°C indicating their good thermal stability. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010