Photodegradation of 2-nitrophenol catalyzed by CoO, CoS and CoO/CoS nanoparticles

The nanoparticles of CoO, CoS and CoO/CoS composite are synthesized using precipitation method. The X-ray diffraction, UV–Vis absorption spectroscopy, energy dispersive X-ray spectroscopy, scanning electron microscopy and FT-IR spectroscopy are used to characterize the prepared nanoparticles. The EDX analysis shows the formation of CoO_0.67S_0.33 composite. The XRD pattern indicates the hexagonal structure for nanocomposite. The formation of Co–O and Co–S bonds is confirmed by FT-IR spectra. The band-gap energies of 2.97, 3.06 and 2.91 eV are obtained from UV–Vis spectra of CoO, CoS and CoO/CoS nanoparticles, respectively. The results of photodegradation of 2-nitrophenol show that the photoreactivity order of nanocatalysts is CoO/CoS > CoO > CoS. The pseudo first-order kinetic rate constants of 6.4 × 10^?3, 4.3 × 10^?3 and 12.2 × 10^?3 min^?1 are obtained for CoO, CoS and CoO/CoS nanoparticles, respectively, at photodegradation reaction conditions of pH 10, 30 mg/L of 2-NP and 1.3 g/L of the catalyst. The proposed nanocomposite shows an acceptable reusability and stability against photocorrosion in four-cycle photodegradation experiments.     

Potassium phthalimide-catalysed one-pot multi-component reaction for efficient synthesis of amino-benzochromenes in aqueous media

2-Amino-4-aryl-4H-benzo[h]chromenes and 3-amino-1-aryl-1H-benzo[f]chromenes were prepared by treating cyano-methylene compounds (malononitrile or ethyl cyanoacetate), substituted aromatic aldehydes, and naphtholic compounds in the presence of potassium phthalimide as a green, mild, efficient, and commercially available organocatalyst in aqueous media. The procedure was readily conducted and affords remarkable advantages such as safety, short reaction times, environmentally benign milder reaction conditions, no organic solvent required, and high yields.     

Potassium phthalimide： An efficient and green organocatalyst for the synthesis of 4-aryl-7-（arylmethylene）-3,4,6,7-tetrahydro-1H- cyclopenta[d]pyrimidin-2（5H）-ones]thiones under solvent-free conditions

An efficient synthesis of Biginelli-type compounds using potassium phthalimide as a green, mild, and commercially available organocatalyst in a one-pot, multi-component cyclocondensation reaction of cyclopentanone, aldehydes, and urea/thiourea is reported. The present methodology is a green approach to access 4-aryl-7-（aryImethylene）-3,4,6,7-tetrahydro-1H-cyclopenta[d]pyrimidin-2（5H）-ones/thiones. It offers several merits such as simple operational procedures, no use of hazardous organic solvents, and cheap and environmentally friendly solid basic catalyst.     

Aqua one-pot,three-component synthesis of dihydropyrano[3,2-c]chromenes and amino-benzochromenes catalyzed by sodium malonate

Research on Chemical Intermediates - The widespread biological properties of dihydropyrano[3,2-c]chromenes, 2-amino-4-aryl-4H-benzo[h]chromenes, and 3-amino-1-aryl-1H-benzo[f]chromenes have led to...     

Sodium ascorbate as an expedient catalyst for green synthesis of polysubstituted 5-aminopyrazole-4-carbonitriles and 6-amino-1,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles

Research on Chemical Intermediates - Sodium ascorbate (SA) was used as a safe catalyst for the synthesis of 5-aminopyrazole-4-carbonitriles from the one-pot three-component cyclocondensation (3-CC)...     

NMR structural elucidation and photochromic behavior of new 1,3-diazabicyclo[3.1.0]hex-3-ene derivatives

Several 6-(4-nitrophenyl)-4-phenyl-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives having various substituents on C² were synthesized, and their ¹H NMR spectra and photochromic behavior were examined.     

Expeditious green synthesis of 3,4-disubstituted isoxazole-5(4<Emphasis Type="Italic">H</Emphasis>)-ones catalyzed by nano-MgO

In this work, it was found that magnesium oxide nanoparticles (nano-MgO) catalyzed one-pot three-component reaction of hydroxylamine hydrochloride with aryl aldehydes (or heteroaryl aldehydes) and β-oxoesters to synthesize some biologically active isoxazole-5(4H)-one-based heterocycles. The reactions were completed using 3 mol% catalyst loading in aqueous medium at room temperature. Nano-MgO was synthesized by precipitation and hydrothermal treatment of aqueous salt solution. The structure of the nano-MgO was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. The presented environmentally friendly heterocyclization offers some interesting merits, including safety, high product yield, mild conditions, low cost, minimal waste, good atom efficiency, catalyst recoverable, energy efficiency, avoidance of hazardous organic solvents, and easy workup.     

Synthesis,spectroscopic investigations,and computational study of 4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)-3-methoxybenzaldehyde

4-((9,10-dioxo-9,10-dihydroanthracen-1-yl)oxy)-3-methoxybenzaldehyde has been synthesized in an attempt to obtain a new photochromic compound. The optimized molecular structure, mole fractions of title compound in trans and ana forms have been investigated. UV-visible spectra of the compound were also recorded. Upon irradiation with 300 nm light, the camel solid turned orange, in which a visible absorption band was observed at 475 nm. The electronic properties, such as HOMO, LUMO and band gap energies were obtained by the time-dependent DFT (TD-DFT) approach. The predicted nonlinear optical properties of the title compound are much greater than those of urea. Transition structures were calculated by QST3 and IRC methods which yielded the potential energy surface and activation energy.     

An expeditious and green one-pot synthesis of 12-substituted-3,3-dimethyl-3,4,5,12-tetrahydrobenzo[b]acridine-1,6,11(2H)-triones

Research on Chemical Intermediates - In this study, several new 12-aryl/heteroaryl-3,3-dimethyl-tetrahydrobenzo[b]acridine-1,6,11(2H)-trione heterocyclic compounds that can be considered as...