Manganese Dioxide (α-MnO2) and Graphene Oxide (GO) Nanocomposites: An Efficient Promotor for the Oxidative Deprotection of Trimethylsilyl, Tetrahydropyranyl and Methoxymethyl Ethers

2021 ◽  
Vol 21 (12) ◽  
pp. 6016-6023
Author(s):  
Pouran Pourayoob Foumani ◽  
Hassan Tajik ◽  
Farhad Shirini ◽  
Shahed Hassanpoor
Keyword(s):  
Graphene Oxide ◽  
Manganese Dioxide ◽  
Heterogeneous Reaction ◽  
Aerobic Oxidation ◽  
Reaction Times ◽  
Efficient Catalyst ◽  
Ft Ir ◽  
Novel Method ◽  
Work Up ◽  
Heterogeneous Reaction Conditions

Manganese dioxide (α-MnO2) and graphene oxide (GO nanocomposites were prepared and successfully characterized using Fourier-transform infrared (FT-IR), field emission scanning-electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX) mapping methods and Xray diffraction (XRD) analyses. This reagent is an efficient catalyst for the aerobic oxidation of trimethylsilyl (TMS), tetrahedropyranyl (THP), and methoxymethyl ethers (MOM) to their corresponding carbonyl compounds in the presence of K2CO3. All reactions were performed in n-hexane under mild and completely heterogeneous reaction conditions. Our novel method has the advantages of excellent yields, short reaction times, availability and reusability of the catalyst and simple and easy work-up procedure compared to the conventional methods reported in the literature.

Ultrasonic Assisted Synthesis of 2, 3-Dihydroquinazolin-4(1H)-ones Involving Three-Component Reaction of Isatoic Anhydride, Amines and Pyrazole Carbaldehydes Catalyzed by [γ-Fe2O3@HAp-SO3H]

2019 ◽  
Vol 17 (1) ◽  
pp. 24-30
Author(s):  
Kiana F. Sina ◽  
Asieh Yahyazadeh ◽  
Nosrat O. Mahmoodi ◽  
Kurosh R. Moghadam ◽  
Mohammad Nikpassand ◽  
...  
Keyword(s):  
Reaction Times ◽  
Isatoic Anhydride ◽  
Bacterial Strains ◽  
One Pot ◽  
Three Component Reaction ◽  
Ultrasonic Assisted ◽  
Ft Ir ◽  
Novel Method ◽  
The One ◽  
Work Up

The combination of [γ-Fe2O3@HAp-SO3H] as a catalyst and ultrasonic effect catalyzed the synthesis of diverse derivatives of 2, 3-dihydroquinazolin-4(1H)-ones which is reported in this study. The products were synthesized via the one-pot three-component reaction of isatoic anhydride, amines and pyrazole carbaldehydes in water: EtOH catalyzed by recoverable [γ-Fe2O3@HAp-SO3H]. This paper conducted an investigation of the effect of various solvents, temperatures and catalysts on the reactions. Short reaction times, mild reaction conditions, simple work-up, the desired yields and the use of an appropriate catalyst are the advantages of this novel method. The new derivatives were validated by using FT-IR, 1HNMR, and 13CNMR. Moreover, the synthesized compounds were screened for their antimicrobial activity against bacterial strains.

Ultrasound-assisted aqua-mediated synthesis of multi-substituted tetrahydropyridine-3-carboxylates using N-carboxymethyl-3-pyridinium hydrogensulfate ([N-CH2CO2H-3-pic]+HSO4−) as a new efficient ionic liquid catalyst

2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Kobra Nikoofar ◽  
Fatemeh Shahriyari
Keyword(s):  
Ionic Liquid ◽  
Reaction Times ◽  
Aromatic Aldehydes ◽  
Environmentally Benign ◽  
H Nmr ◽  
Sonic Waves ◽  
Ft Ir ◽  
High Yields ◽  
Work Up ◽  
C Nmr

AbstractA simple, straightforward, and ultrasound-promoted method for the preparation of some highly functionalized tetrahydropyridines reported via pseudo five-component reaction of (hetero)aromatic aldehydes, different anilines, and alkyl acetoacetates in the presence of [N-CH2CO2H-3-pic]+HSO4−, as a novel ionic liquid, in green aqueous medium. The IL was synthesized utilizing simple and easily-handled substrates and characterized by FT-IR, 1H NMR, 13C NMR, GC-MASS, FESEM, EDX, and TGA/DTG techniques. The procedure contains some highlighted aspects which are: (a) performing the MCR in the presence of aqua and sonic waves, as two main important and environmentally benign indexes in green and economic chemistry, (b) high yields of products within short reaction times, (c) convenient work-up procedure, (d) preparing the new IL via simple substrates and procedure.

Diastereoselective Synthesis of Functionalised Trans-Tetrahydrobenzofuran-4-Ones in an Aqueous Medium by using DABCO as an Efficient Catalyst

2017 ◽  
Vol 41 (11) ◽  
pp. 657-660 ◽  
Author(s):  
Mohammad Reza Salari ◽  
Mohammad H. Mosslemin ◽  
Alireza Hassanabadi
Keyword(s):  
Aqueous Medium ◽  
High Purity ◽  
Reaction Times ◽  
Diastereoselective Synthesis ◽  
Efficient Synthesis ◽  
One Pot ◽  
Efficient Catalyst ◽  
Pyridinium Bromide ◽  
Work Up

A one-pot, efficient synthesis of 11 novel 2,3-diacylated trans-tetrahydrobenzofuran-4-one derivatives has been achieved via a three-component condensation of a N-(4-halophenacyl)-pyridinium bromide, a cyclic 1,3-diketone such as 5,5-dimethyl-1,3-cyclohexanedione (dimedone) or cyclohexane-1,3-dione and an arylglyoxal in the presence of catalytic amounts of 1,4-diaza-bicyclo[2.2.2]octane (DABCO) in water under reflux conditions. The attractive features of the method are excellent yields and high purity, short reaction times, easy work-up, and use of an inexpensive and non-toxic catalyst.

scholarly journals Leucine: green and efficient catalyst for the synthesis of 4H-chromenes

2017 ◽  
Vol 10 (9) ◽  
pp. 3197-3202 ◽  
Author(s):  
Davood Azarifar ◽  
Younes Abbasi ◽  
Omolbanin Badalkhani
Keyword(s):  
Amino Acid ◽  
Condensation Reaction ◽  
Reaction Times ◽  
Aromatic Aldehydes ◽  
One Pot ◽  
Efficient Catalyst ◽  
Naturally Occurring ◽  
The One ◽  
High Yields ◽  
Work Up

Leucine, a naturally occurring α-amino acid, has been found as an effective catalyst to effect the one-pot three-component condensation reaction between aromatic aldehydes, malononitrile and 5,5-dimethyl-1,3-cyclohexanedione (dimedone). Various 2-amino-4-aryl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile derivatives are conveniently prepared by these reactions in excellent yields. High yields, short reaction times, simple work-up, use of green and naturally occurring catalyst and solvent are the main merits of the present protocol. 

Coaled Carbon-Based Solid Acid: a New and Efficient Catalyst for Click Synthesis of 3,4-Dihydropyrimidin-2(1H)-Ones under Solvent-Free Conditions

2013 ◽  
Vol 634-638 ◽  
pp. 504-507
Author(s):  
Wan Yi Liu ◽  
Ning Liu ◽  
Rui Yuan Zheng ◽  
Bing Li ◽  
Xia Zhang ◽  
...  
Keyword(s):  
Solid Acid ◽  
Reaction Times ◽  
Solvent Free ◽  
Multicomponent Synthesis ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Important Addition ◽  
High Yields ◽  
Work Up ◽  
Carbon Based

Coaled carbon-based solid acid (CCBSAC) is reported as a new, efficient and recyclable catalyst for the regioselective multicomponent synthesis of dihydropyrimidin-2(1H)-ones from aldehydes, β-ketoesters and urea or thiourea under solvent-free conditions. The structure and thermal stability of CCBSAC which resulted from ultra-clean coal resources mainly were characterized by IR, XRD, and TG. Nineteen dihydropyrimidin-2(1H)-ones examples were prepared and this catalyst could recycle up to 4 consecutive runs without losing its efficiency. The high yields of products, short reaction times, ease of work-up and clean procedure will make the present method a useful and important addition to the previous methodologies for the synthesis of dihydropyrimidin-2(1H)-ones.

scholarly journals Rapid Four-component Synthesis of Dihydropyrano[2,3-c]pyrazoles using Nano-egg Shell/Ti(IV) as a Highly Compatible Natural Based Catalyst

2020 ◽  
Author(s):  
Arefeh Dehghani Tafti ◽  
Bi BiFatemeh Mirjalili ◽  
Abdolhamid Bamoniri ◽  
Naeimeh Salehi
Keyword(s):  
Thermo Gravimetric Analysis ◽  
Reaction Times ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
Ft Ir ◽  
Egg Shell ◽  
High Yields ◽  
Work Up

Abstract Nano-egg shell/Ti(IV) (NEST) as a novel naturally based catalyst was prepared, characterized and applied for the synthesis of dihydropyrano[2,3-c]pyrazole [DHPP] derivatives. The characterization of NEST was performed using Fourier Transform Infrared (FT-IR) spectroscopy, X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy-Dispersive X-ray Spectroscopy (EDX), and Thermo Gravimetric Analysis (TGA). DHPPs were synthesized in the presence of NEST via a four component reaction of aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate at room temperature under solvent free conditions. The principal affairs of this procedure are easy work-up, high yields of pure products without the use of any toxic organic solvents, mild condition and short reaction times.

scholarly journals Preparation and characterization of ZrO2 supported Fe3O4 MNPs as an effective and reusable superparamagnetic catalyst for the riedländer synthesis of quinoline derivatives

2015 ◽  
Vol 80 (8) ◽  
pp. 971-982 ◽  
Author(s):  
Seyyedeh Hejazi ◽  
Abdollah Shojaei ◽  
Khalil Tabatabaeian ◽  
Farhad Shirini
Keyword(s):  
Magnetic Field ◽  
Reaction Times ◽  
Quinoline Derivatives ◽  
Considerable Decrease ◽  
Ft Ir ◽  
High Yields ◽  
Green Procedure ◽  
Work Up ◽  
Fe3o4 Mnps

In this study, a convenient, appropriate and eco-friendly method for the synthesis of quinoline derivatives via Friedl?nder reaction has been developed by using ZrO2/Fe3O4-MNPs as an effective and reusable heterogeneous catalyst. The morphology of ZrO2/Fe3O4-MNPs has been studied by XRD, FT-IR, SEM, TEM and VSM techniques. Green procedure, straight and easy work-up, high yields of the products and good reaction times are the benefits of this procedure. Further, the catalyst can be recovered by external magnetic field and reused at least for three times without a considerable decrease in its catalytic activity.

Sign in / Sign up

Export Citation Format

Share Document