Room Temperature N-Arylation of 1,2,4-Triazoles under Ligand-Free Condition

A simple and efficient method for N-arylation of 1,2,4-triazole at room temperature was described by the use of predominant (111) facet CuO nanoparticles as a catalyst in ligand-free condition. The catalyst was recyclable, and a variety of substrates give N-arylation product in high yield with short period of reaction time. The wide scope of this catalyst led us to investigate transformations involving less-reactive nitrogen nucleophiles, such as imidazole and pyrazoles. We were pleased to find that various derivatives of azoles were effectively coupled with aryl iodide to afford the desired N-arylated product in excellent yield.

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Asymmetric induction in the Sommelet rearrangement of chiral benzyl sulfonium salts

Canadian Journal of Chemistry ◽

10.1139/v76-031 ◽

1976 ◽

Vol 54 (2) ◽

pp. 193-201 ◽

Cited By ~ 18

Author(s):

Stewart John Campbell ◽

David Darwish

Keyword(s):

Sodium Methoxide ◽

Room Temperature ◽

Exchange Resin ◽

Shift Reagent ◽

Asymmetric Induction ◽

High Yield ◽

Sulfonium Salts ◽

Sodium Methoxide Solution ◽

Derivatives Of ◽

Sulfone Derivatives

The Sommelet rearrangement of (+)-ethylmethyl-p-nitrobenzylsulfonium perchlorate, (+)-1, and (+)-ethylmethyl-p-chlorobenzylsulfonium perchlorate, (+)-2, are described. Elution of (+)-1 through an hydroxide exchange resin generated ethylmethylsulfonium p-nitro-benzylide (+)-3 which decomposed in methanol at room temperature to ethyl 2-methyl-5-nitro-benzyl sulfide, 6, and (+)-methyl α-(2-methyl-5-nitrophenyl)ethyl sulfide, (+)-7, with 18 to 20.3% asymmetric induction. Decomposition of (+)-2 in sodium methoxide solution at 70 °C for 2 h produced ethyl 2-methyl-5-chlorobenzyl sulfide, 8, and (+)-methyl α-(2-methyl-5-nitro-phenyl)ethyl sulfide, (+)-9, with 21 to 25.5% asymmetric induction. The lower estimates of asymmetric induction for each sulfide were made by comparison with specific rotations of authentic samples obtained by synthesis and resolution. The higher estimates were obtained by the use of a chiral lanthanide shift reagent Eu(hfbc)3 with the sulfone derivatives of these chiral sulfides. The ylide (+)-3 reacted with aldehydes in high yield to produce oxiranes with no induction of asymmetry.

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An efficient green synthesis of polyfunctional pyrazole-triazole hybrids and bis-triazoles via chromium incorporated fluorapatite encapsulated iron oxide nanocatalyst

Current Chemistry Letters ◽

10.5267/j.ccl.2021.4.006 ◽

2021 ◽

Vol 10 (4) ◽

pp. 445-458 ◽

Cited By ~ 1

Author(s):

Iman Rezaei ◽

Manouchehr Mamaghani

Keyword(s):

Iron Oxide ◽

Reaction Time ◽

Green Synthesis ◽

Room Temperature ◽

Reaction Times ◽

Catalytic Performance ◽

High Yield ◽

External Magnet ◽

Ft Ir ◽

Derivatives Of

In this report, novel chromium incorporated fluorapatite encapsulated iron oxide (γ-Fe2O3@FAp@Cr) nanocatalyst was synthesized and characterized by FT-IR, TEM, SEM, XRD and EDX techniques. The catalyst was used in the synthesis of various derivatives of pyrazole-triazole hybrids via the reaction of thiosemicarbazide or semicarbaside and pyrazolecarbaldehydes at room temperature with excellent yields and short reaction times. The protocol was also used in the synthesis of bis-triazoles in high yield and reasonable reaction time. The nanocatalyst was comfortably separated from the reaction mixture by an external magnet and was reused in six consecutive cycles without any remarkable changes in its catalytic performance.

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PEG1000 as a Low Melting and Ecofriendly Solvent for Air Oxidative and Catalyst Free 2,4-Disubstitute Quinazoline Synthesis

Letters in Organic Chemistry ◽

10.2174/1570178616666190417122005 ◽

2020 ◽

Vol 17 (9) ◽

pp. 709-716

Author(s):

Ebrahim Saeedian Moghadam ◽

Shahrzad Ghafary ◽

Mohsen Amini

Keyword(s):

Melting Point ◽

High Yield ◽

Purification Process ◽

Poly Ethylene Glycol ◽

Free Condition ◽

Catalyst Free ◽

Privileged Scaffold ◽

Quinazoline Derivatives ◽

Poly Ethylene ◽

Work Up

With regard to the importance of quinazoline as a privileged scaffold, herein we report the synthesis of twenty seven 2,4-disubstitute quinazoline derivatives in a new catalyst free condition. In the current work, poly ethylene glycol (PEG1000) as an inexpensive, very simple commercially available, ecofriendly and low melting point solvent was used. Air bubbling, a green oxidant, for oxidation purpose was also used. This is the first report about using PEG1000 as a solvent simultaneously with air bubbling as oxidant in quinazoline synthesis. All of the compounds 1-27 were synthesized in high yield with very simple work up and purification process without using column chromatography. All the structures were confirmed using 1H NMR, 13C NMR, IR, MS and elemental analysis.

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4-Hydroxy Pyridinium Triflate@SiO2 Nanoparticles as a Novel Efficient Catalyst for Fries Rearrangement of Aryl Esters with High Selectivity

Current Organic Synthesis ◽

10.2174/1570179417666200713175943 ◽

2020 ◽

Vol 17 (8) ◽

pp. 654-660

Author(s):

Shermineh Sadat Ghalehbandi ◽

Dadkhoda Ghazanfari ◽

Sayed Ali Ahmadi ◽

Enayatollah Sheikhhosseini

Keyword(s):

High Selectivity ◽

Sio2 Nanoparticles ◽

High Yield ◽

Synthetic Method ◽

Functionalized Silica ◽

Efficient Catalyst ◽

Fries Rearrangement ◽

Free Condition ◽

Solvent Free Condition ◽

Work Up

Introduction: We developed a simple, fast and new method for the Fries rearrangement of aryl esters. Materials and Methods: 4-Hydroxy pyridinium triflate functionalized silica is a very efficient, reusable and economically available catalyst for the Fries rearrangement in solvent-free condition and under microwave irradiation. Results and Discussion: Also, a notable selectivity was observed in the presence of 4-hydroxy pyridinium triflate functionalized silica. Conclusion: Selectivity, shorter reaction time, high yield, and easy work-up are advantages of this synthetic method.

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Development of the room temperature protocol based on room temperature ionic liquids and surfactant ionic liquids for the synthesis of derivatives of 2-amino-thiazoles and thermo-physical analysis of the synthesized derivatives using TGA-DSC.

Current Physical Chemistry ◽

10.2174/1877946810999200519102040 ◽

2020 ◽

Vol 10 ◽

Cited By ~ 1

Author(s):

Chandrakant Sarode ◽

Sachin Yeole ◽

Ganesh Chaudhari ◽

Govinda Waghulde ◽

Gaurav Gupta

Keyword(s):

Thermal Analysis ◽

Heat Capacity ◽

Ionic Liquids ◽

Specific Heat ◽

Specific Heat Capacity ◽

Room Temperature ◽

Heat Capacity Data ◽

General Strategy ◽

Capacity Data ◽

Derivatives Of

Aims: To develop an efficient protocol, which involves an elegant exploration of the catalytic potential of both the room temperature and surfactant ionic liquids towards the synthesis of biologically important derivatives of 2-aminothiazole. Objective: Specific heat capacity data as a function of temperature for the synthesized 2- aminothiazole derivatives has been advanced by exploring their thermal profiles. Method: The thermal gravimetry analysis and differential scanning calorimetry techniques are used systematically. Results: The present strategy could prove to be a useful general strategy for researchers working in the field of surfactants and surfactant based ionic liquids towards their exploration in organic synthesis. In addition to that, effect of electronic parameters on the melting temperature of the corresponding 2-aminothiazole has been demonstrated with the help of thermal analysis. Specific heat capacity data as a function of temperature for the synthesized 2-aminothiazole derivatives has also been reported. Conclusion: Melting behavior of the synthesized 2-aminothiazole derivatives is to be described on the basis of electronic effects with the help of thermal analysis. Additionally, the specific heat capacity data can be helpful to the chemists, those are engaged in chemical modelling as well as docking studies. Furthermore, the data also helps to determine valuable thermodynamic parameters such as entropy and enthalpy.

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High yield room temperature conversion of carbon dioxide into cyclic carbonates catalyzed by mixed metal oxide (CuO‐ZnO) nano‐flakes/micro‐flakes (Cozi‐nmf)

Applied Organometallic Chemistry ◽

10.1002/aoc.6224 ◽

2021 ◽

Author(s):

Venkateswara Rao Velpuri ◽

Krishnamurthi Muralidharan

Keyword(s):

Carbon Dioxide ◽

Metal Oxide ◽

Room Temperature ◽

High Yield ◽

Mixed Metal Oxide ◽

Cyclic Carbonates ◽

Mixed Metal

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ZnO/RGO Heterojunction Based near Room Temperature Alcohol SENSOR with Improved Efficiency

Engineering Proceedings ◽

10.3390/i3s2021dresden-10073 ◽

2021 ◽

Vol 6 (1) ◽

pp. 25

Author(s):

Sanghamitra Ghosal ◽

Partha Bhattacharyya

Keyword(s):

Active Sites ◽

Room Temperature ◽

Surface Engineering ◽

Gas Sensing ◽

Energy Band Diagram ◽

Future Generation ◽

High Yield ◽

Synthesis Process ◽

Ethanol Sensor ◽

Vapor Sensing

The systematic optimization of surface engineering (dimensionality) indeed plays a crucial role in achieving efficient vapor-sensing performance. Among various semiconducting metal oxides, owing to some of its unique features and advantages, ZnO has attracted researchers on a global scale due to its application in various fields, including chemical sensors. The concomitant optimization of the surface attributes (varying different dimensions) of ZnO have become a sensation for the entire research community. Moreover, the small thickness and extremely large surface of exfoliated 2D nanosheets render the gas sensing material an ideal candidate for achieving strong coupling with different gas molecules. However, temperature is a crucial factor in the field of chemical sensing. Recently, graphene-based gas sensors have attracted attention due to their variety of structures, unique sensing performances and room temperature working conditions. In this work, a highly sensitive and fast responsive low temperature (60 °C)-based ethanol sensor, based on RGO/2D ZnO nanosheets hybrid structure, is reported. After detailed characterizations, the vapor sensing potentiality of this sensor was tested for the detection of ethanol. The ethanol sensor offered the response magnitude of 89% (100 ppm concentration) with response and recovery time of 12 s/29 s, respectively. Due to excessively high number of active sites for VOC interaction, with high yield synthesis process and appreciably high carrier mobility, this has paved the way for developing future generation, miniaturized and flexible (wearable) vapor sensor devices, meeting the multidimensional requirements for traditional and upcoming (health/medical sector) applications. The underlying mechanistic framework for vapor sensing, using this hybrid junction, is explained with the Energy Band Diagram.

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