Preparation of 1H-pyrazolo[1,2-b]phthalazine-5,10-diones using ZrO2 nanoparticles as a catalyst under solvent-free conditions

2017 ◽  
Vol 23 (5) ◽  
Author(s):  
Mohammad Piltan
Keyword(s):  
Zirconium Oxide ◽  
Solvent Free ◽  
Zro2 Nanoparticles ◽  
Oxide Nanoparticles ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Zirconium Oxide Nanoparticles

AbstractZirconium oxide nanoparticles are an efficient catalyst for the preparation of 1

scholarly journals IMPROVING THE ANTIBACTERIAL ACTIVITY BY THE COMBINATION OF ZIRCONIUM OXIDE NANOPARTICLES (ZrO2) AND CEFTAZIDIME AGAINST KLEBSIELLA PNEUMONIAE

2019 ◽  
Vol 1 (1) ◽  
pp. 16-20
Keyword(s):  
Antibacterial Activity ◽  
Nosocomial Infection ◽  
Zirconium Oxide ◽  
Respiratory Tract Infections ◽  
Zro2 Nanoparticles ◽  
Oxide Nanoparticles ◽  
Opportunistic Pathogens ◽  
Inhibition Zones ◽  
Tract Infections ◽  
Zirconium Oxide Nanoparticles

Introduction: Klebsilla pneumoniae is one of must opportunistic pathogens that causes nosocomial infection, UTI, respiratory tract infections and blood infections. ZrO2 nanoparticles have antimicrobial activity against some pathogenic bacteria and fungi. Ceftazidime is one of third generation cephalosporins groups of antibiotecs, characterized by its broad spectrum on bacteria in general and particularly on Enterobacteriaceae family like Klebsiella spp. Method: Diverse clinical samples of Klebsilla pneumoniae were isolated from several hospitals in Baghdad – Iraq and ZrO2 nanoparticles was investigated against it. Ceftazidime was also investigated against K. pneumoniae. Both of ZrO2 nanoparticles and ceftazidime were mixed together and investigated against K. pneumoniae. Results: The result showed that ZrO2 nanoparticles were effectivity on inhibiting opportunistic pathogens. By using zirconium oxide nanoparticles on Klebsiella pneumonia isolates in 24h. of incubation time, inhibition zones were (38,34,10,10,8,0) mm respectively on agar plates. By using ceftazidime alone against the same bacteria inhibition zones were (40,32,10,9,8,0) mm. respectively. Conclusion:The present study results that the antibacterial activity of ceftazidime against bacteria was increased when combination between ZrO2 nanoparticles and the antibiotic had done, because, inhibition zones in case of mixing both of ZrO2 nanoparticles and ceftazidime were (43,40,12,12,10,0) mm respectively. So that we can conclude that the combination of zirconium oxide nanoparticles (ZrO2) and ceftazidime was a useful method for the treatment of Klebsilla pneumonia that cause nosocomial infection, UTI, respiratory tract infections and blood infections.

Synthesis and Characterisation of Pure Zirconium Oxide (ZrO2) Nanoparticle by Conventional Precipitation Method

2021 ◽  
Vol 10 (4) ◽  
pp. 19-21
Author(s):  
V. Gayathri ◽  
R. Balan
Keyword(s):  
Light Scattering ◽  
Dynamic Light Scattering ◽  
Zirconium Oxide ◽  
Precipitation Method ◽  
Zro2 Nanoparticles ◽  
Oxide Nanoparticles ◽  
Visible Spectroscopy ◽  
Pure Zirconium ◽  
Ft Ir ◽  
Zirconium Oxide Nanoparticles

In this paper, the synthesis of Zirconium oxide (ZrO2) nanoparticles was carried out by the Conventional precipitation method. Ultraviolet, visible spectroscopy (UV-Vis), and dynamic light scattering analysis (DLS) were performed to find the particles' bandgap and size. Fourier transform infrared spectroscopy (FT-IR) observed the characteristic bands of Zirconium oxide nanoparticles. Dynamic light scattering analysis showed that the size of the particle was found to be 119 nm.

Preparation and Characterization of a Novel Room Temperature Dicationic Ionic Liquid and its Application in the Synthesis of Xanthenediones Under Solvent-Free Conditions

2018 ◽  
Vol 21 (8) ◽  
pp. 602-608 ◽  
Author(s):  
Zainab Ehsani-Nasab ◽  
Ali Ezabadi
Keyword(s):  
Ionic Liquid ◽  
Room Temperature ◽  
Reaction Times ◽  
Significant Loss ◽  
Solvent Free ◽  
Acidity Function ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Hammett Acidity Function ◽  
Dicationic Ionic Liquid

Aim and Objective: In the present work, 1, 1’-sulfinyldiethylammonium bis (hydrogen sulfate) as a novel room temperature dicationic ionic liquid was synthesized and used as a catalyst for xanthenediones synthesis. Material and Method: The dicationic ionic liquid has been synthesized using ethylamine and thionyl chloride as precursors. Then, by the reaction of [(EtNH2)2SO]Cl2 with H2SO4, [(EtNH2)2SO][HSO4]2 was prepared and after that, it was characterized by FT-IR, 1H NMR, 13C NMR as well as Hammett acidity function. This dicationic ionic liquid was used as a catalyst for the synthesis of xanthenediones via condensation of structurally diverse aldehydes and dimedone under solvent-free conditions. The progress of the reaction was monitored by thin layer chromatography (ethyl acetate/n-hexane = 3/7). Results: An efficient solvent-free method for the synthesis of xanthenediones has been developed in the presence of [(EtNH2)2SO][HSO4]2 as a powerful catalyst with high to excellent yields, and short reaction times. Additionally, recycling studies have demonstrated that the dicationic ionic liquid can be readily recovered and reused at least four times without significant loss of its catalytic activity. Conclusion: This new dicationic ionic liquid can act as a highly efficient catalyst for xanthenediones synthesis under solvent-free conditions.

Synthesis of Dihydropyrimidinones (DHPMs) and Hexahydro Xanthene Catalyzed by 1,4-Diazabicyclo [2.2.2] Octane Triflate Under Solvent-Free Condition

2019 ◽  
Vol 16 (5) ◽  
pp. 776-786 ◽  
Author(s):  
Deepa ◽  
Geeta D. Yadav ◽  
Mohd J. Aalam ◽  
Pooja Chaudhary ◽  
Surendra Singh
Keyword(s):  
Ethyl Acetoacetate ◽  
Biginelli Reaction ◽  
Solvent Free ◽  
Efficient Catalyst ◽  
Solvent Free Condition ◽  
Solvent Free Conditions ◽  
Xanthene Derivatives ◽  
Different Temperatures ◽  
Flash Column Chromatography ◽  
Biginelli Condensation

Objective:DABCO salts were evaluated as catalysts for the Biginelli reaction between 4- methoxybenzaldehyde, urea and ethyl acetoacetate under solvent-free conditions. 1,4-Diazabicyclo [2.2.2] octane triflate was found to be a simple, inexpensive, highly efficient catalyst for Biginelli reaction for a variety aromatic aldehyde with urea and ethyl acetoacetate at 80°C afforded corresponding 3,4-dihydropyrimidinones in 50-99% yields after 30-120 minutes. 1,3-Cyclohexadione was used in place of ethyl acetoacetate in the absence of urea this methodology is giving hexahydro xanthene derivatives in good to excellent yields after 3-4 hours.Methods:DABCO salt 4 (5 mol%), 4-methoxybenzaldehyde (0.73 mmol) and urea (0.73 mmol) were stirred for 10 minutes at 80°C, then ethyl acetoacetate (1.5 equiv.) was added and reaction mixture was stirred at 80°C for specified time. The resulting solution was stirred continuously and progress of the reaction was followed by TLC. The crude reaction mixture was purified by flash column chromatography on silica gel (hexane/ethyl acetate (1:2)) to give pure desired product.Results:Reaction conditions of the Biginelli reaction were optimized using 4-methoxybenzaldehyde (0.73 mmol), urea (0.73 mmol), and ethyl acetoacetate (5 equiv.) as model substrates catalyzed by 1,4-Diazabicyclo [2.2.2] octane triflate (5 mol%) in a different solvents, screening of different catalysts and different temperatures. Neat condition was found to be the best for the Biginelli condensation and corresponding 3,4- dihydropyrimidinones was obtained in good to excellent yields. When the reaction was carried out with benzaldehyde derivatives and cyclohexane-1,3-dione in place of ethyl acetoacetate in the absence of urea, solely corresponding hexahydro xanthene derivatives were obtained in 61-91% yields.Conclusion:In conclusion, we have applied salts of 1,4-Diaza-bicyclo [2.2.2] octane as catalysts in the Biginelli condensation and corresponding 3,4-dihydropyrimidinones were obtained in 50- 99% yields under solvent free conditions. This methodology is having advantages like simple work-up; low loading of catalyst and reaction was performed at moderate temperature under solvent-free conditions.

Basic Alumina as an Efficient Catalyst for Preparation of Semicarbazones in Solvent Free Conditions

2007 ◽  
Vol 54 (5) ◽  
pp. 1337-1339 ◽  
Author(s):  
Ali Reza Kiasat ◽  
Foad Kazemi ◽  
Mehdi Fallah Mehrjardi
Keyword(s):  
Solvent Free ◽  
Efficient Catalyst ◽  
Basic Alumina ◽  
Solvent Free Conditions
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