Catalytic acetylation of (+)-cedrol with heterogeneous catalyst H2SO4/SiO2 under solvent free conditions

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Acetic Anhydride ◽  
Heterogeneous Catalyst ◽  
Silica Gel ◽  
Solvent Free ◽  
Molar Ratio ◽  
Optimum Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Solvent Free Conditions ◽  
Bet Method

Heterogeneous catalyst, H2SO4/SiO2 was synthesized by immobilizing sulfuric acid on silica gel as solid support. Silica gel was prepared from kaolin, originating from Belitung island Indonesia. The synthesized catalyst was characterized by various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform Infrared spectroscopy and BET method and was applied for the acetylation of (+)-cedrol compound using acetic anhydride under solvent free conditions. The optimum conditions for catalytic acetylation were found at 353 K for 20 h reaction period, the molar ratio (+)-cedrol/acetic anhydride 1:10 in the presence of 5%-w of catalyst converted 88,7% (+)-cedrol into cedryl acetate. Results revealed catalyst could possibly be used for cedryl acetate synthesis from (+)-cedrol.

Silica-supported barium chloride (SiO2–BaCl2) — Efficient and heterogeneous catalyst for the environmentally friendly preparation of N,N′-alkylidene bisamides under solvent-free conditions

2011 ◽  
Vol 89 (5) ◽  
pp. 555-561 ◽  
Author(s):  
Mohammad Reza Mohammad Shafiee
Keyword(s):  
Heterogeneous Catalyst ◽  
Aromatic Aldehyde ◽  
Environmentally Friendly ◽  
Barium Chloride ◽  
Solvent Free ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phenyl Acetylene ◽  
Solvent Free Conditions

A series of N,N′-alkylidene bisamides were prepared via a green and environmentally friendly synthetic protocol from the reaction of phenyl acetylene or hex-1-yne, aromatic aldehyde, and benzamide or acetamide. Silica-supported barium chloride (SiO2–BaCl2) catalyzes the process of the reaction. The prepared catalysts were characterized by X-ray diffraction, and the products were obtained with high conversions and yields.

scholarly journals Acetylation of Eugenol on Functionalized Mesoporous Aluminosilicates Synthesized from Amazonian Flint Kaolin

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 478 ◽  
Author(s):  
Alex de Nazaré de Oliveira ◽  
Erika Tallyta Leite Lima ◽  
Eloisa Helena de Aguiar Andrade ◽  
José Roberto Zamian ◽  
Geraldo Narciso da Rocha Filho ◽  
...  
Keyword(s):  
Acetic Anhydride ◽  
Textural Properties ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Mesoporous Catalyst ◽  
Reaction Conditions ◽  
Alternative Source ◽  
X Ray ◽  
Acidic Sites ◽  
Catalyst Temperature

The present work was aimed to investigate the catalytic activity of a mesoporous catalyst synthesized from 3-mercaptopropyltrimethoxysilane (MPTS) functionalized Amazonian flint kaolin in the acetylation of eugenol with acetic anhydride. Materials were characterized by thermogravimetry (TGA), N2 adsorption (BET), X-ray dispersive energy spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and acid-base titration. The results presented proved the efficiency of flint kaolin as an alternative source in the preparation of mesoporous materials, since the material exhibited textural properties (specific surface area of 1071 m2 g−1, pore volume of 1.05 cm3 g−1 and pore diameter of 3.85 nm) and structural properties (d100 = 4.35 nm, a0 = 5.06 nm and Wt = 1.21 nm) within the required and characteristic material standards. The catalyst with the total amount of acidic sites of 4.89 mmol H+ g−1 was efficient in converting 99.9% of eugenol (eugenol to acetic anhydride molar ratio of 1:5, 2% catalyst, temperature and reaction time 80 °C and 40 min reaction). In addition, the reused catalyst could be successfully recycled with 92% conversion activity under identical reaction conditions.

scholarly journals 1D Zn(II) Coordination Polymers as Effective Heterogeneous Catalysts in Microwave-Assisted Single-Pot Deacetalization-Knoevenagel Tandem Reactions in Solvent-Free Conditions

Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 90
Author(s):  
Anup Paul ◽  
Anirban Karmakar ◽  
M. Fátima C. Guedes da Silva ◽  
Armando J. L. Pombeiro
Keyword(s):  
Carboxylic Acid ◽  
Diffraction Analysis ◽  
Heterogeneous Catalysts ◽  
Topological Analysis ◽  
Solvent Free ◽  
Tandem Reactions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Assisted ◽  
Solvent Free Conditions

The new 1D CPs [Zn(L1)(H2O)4]n.nH2O (1) and [Zn(L2)(H2O)2]n (2) [L1 = 1,1′-(ethane-1,2-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid); L2 = 1,1′-(propane-1,3-diyl)bis(6-oxo-1,6-dihydropyridine-3-carboxylic acid)] were prepared from flexible dicarboxylate pro-ligands (H2L1 and H2L2). Both CPs 1 and 2 were characterized by elemental, FTIR, and powder X-ray diffraction analysis. Their geometry and the structural features were unveiled by single-crystal X-ray diffraction analysis. The underlying topology of the CPs was illustrated by the topological analysis of the H-bonded structure of CP 1, which revealed a 3,4,6-connected trinodal net. On the other hand, topological analysis on the hydrogen-bonded network of CP 2 showed a 2,3,3,4,6,7-connected hexanodal net. The thermal stability of the CPs was investigated by thermogravimetric analysis. CPs 1 and 2 act as heterogeneous catalysts in one-pot tandem deacetalization–Knoevenagel condensation reactions under environmentally mild conditions. CPs 1 exhibits a yield of ca. 91% in a microwave-assisted solvent-free medium, whereas a slightly lower yield was obtained for CP 2 (87%) under the same experimental protocol. The recyclability of catalyst 1 was also assessed. To our knowledge, these are the first Zn(II)-based CPs to be applied as heterogeneous catalysts for the above tandem reactions under environmentally friendly conditions.

scholarly journals An Ecofriendly Synthesis of 2-oxazolidinone From 2-aminoethanol and Urea Under Solvent-free Condition Using CeO2 Nanoparticles

2021 ◽  
Author(s):  
ALI NEMATI KHARAT ◽  
Mehrnaz Aliahmadi
Keyword(s):  
Gas Adsorption ◽  
Sol Gel ◽  
Solvent Free ◽  
X Ray Diffraction ◽  
Nitrogen Gas ◽  
X Ray ◽  
Solvent Free Condition ◽  
Solvent Free Conditions ◽  
Adsorption Desorption ◽  
Desorption Method

Abstract Cerium dioxide nanoparticles were prepared by the sol-gel method using cellulose as a template and used in the synthesis of 2-oxazolidinone from urea and 2-aminoethanol under solvent-free conditions. All the reaction parameters were optimized to obtain the best selectivity and conversion. The selectivity of 100 % to 2-oxazolidinone with a pretty complete conversion of about 98.4 % was achieved. The prepared catalyst was characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and volumetric isothermal nitrogen gas adsorption-desorption method (BET).

Friedel–Crafts alkylation of 4-hydroxycoumarin over silica-bonded 1,4-diaza-bicyclo[2.2.2] octane-sulfonic acid chloride as nanostructured heterogeneous catalyst

2017 ◽  
Vol 95 (1) ◽  
pp. 16-21 ◽  
Author(s):  
Ehsan Noroozizadeh ◽  
Ahmad Reza Moosavi-Zare ◽  
Mohammad Ali Zolfigol ◽  
Abdolkarim Zare ◽  
Mahmoud Zarei
Keyword(s):  
Heterogeneous Catalyst ◽  
Acid Chloride ◽  
Sulfonic Acid ◽  
Condensation Reaction ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
X Ray Diffraction ◽  
Efficient Catalyst ◽  
X Ray ◽  
Solvent Free Conditions

A novel nanostructured heterogeneous catalyst, namely silica-bonded 1,4-diaza-bicyclo[2.2.2]octane-sulfonic acid chloride (SBDBSAC), has been synthesized and fully characterized by several techniques, including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), differential thermal gravimetric (DTG), scanning electron microscope (SEM), and energy dispersive X-ray analysis (EDX). Afterward, the nanostructured catalyst was utilized as an efficient catalyst for the synthesis of bis-coumarin derivatives by the condensation reaction of arylaldehydes with 4-hydroxycoumarin at 70 °C under solvent-free conditions.

Efficient thioacetalisation of carbonyl compounds

2014 ◽  
Vol 68 (3) ◽  
Author(s):  
Davood Habibi ◽  
Payam Rahmani ◽  
Ziba Akbaripanah
Keyword(s):  
Reaction Time ◽  
Heterogeneous Catalyst ◽  
Sulphuric Acid ◽  
Silica Gel ◽  
Carbonyl Compounds ◽  
Solvent Free ◽  
Short Reaction Time ◽  
Solvent Free Conditions ◽  
Derivatives Of ◽  
Efficient Heterogeneous Catalyst

AbstractThe thioacetalisation of a variety of heterocyclic, aromatic, and aliphatic carbonyl compounds (1 mmol) with ethane-1,2-dithiol (1 mmol) using silica sulphuric acid (SSA) is presented as an efficient heterogeneous catalyst under mild and solvent-free conditions at 60°C. The thioacetals were formed within a short reaction time (1–34 min) and isolated with 90–98 % yield following an extractive procedure and chromatography on silica gel. The competitive protection reaction between aldehyde and ketone with ethane-1,2-dithiol afforded the protected derivatives of benzaldehyde and acetophenone with 92 % and 8 % yields, respectively, indicating some selectivity.

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