scholarly journals LiHSO4/SiO2as a New, Efficient and Reusable Catalytic System for the Chemoselective Conversion of Aldehydes to Acylals under Solvent-Free Conditions

2009 ◽  
Vol 6 (s1) ◽  
pp. S390-S396 ◽  
Author(s):  
Abdolkarim Zare ◽  
Alireza Hasaninejad ◽  
Esmael Rostami ◽  
Ahmad Reza Moosavi-Zare ◽  
Maria Merajoddin ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Acetic Anhydride ◽  
Catalytic System ◽  
Catalytic Amount ◽  
Significant Loss ◽  
Solvent Free ◽  
Reaction Conditions ◽  
Highly Efficient ◽  
Solvent Free Conditions

A highly efficient, green and expeditious solvent-free method is described for the chemoselective conversion of aldehydes to the corresponding acylals in excellent yields, using acetic anhydride in the presence of catalytic amount (20 mol%) of silica-supported LiHSO4. Ketones does not react under these reaction conditions. LiHSO4/SiO2can be recovered and reused without any significant loss of its catalytic activity.

Al(OTf)3 — A highly efficient catalyst for the tetrahydropyranylation of alcohols under solvent-free conditions

2008 ◽  
Vol 86 (12) ◽  
pp. 1099-1104 ◽  
Author(s):  
Ahmed Kamal ◽  
M Naseer A Khan ◽  
Y VV Srikanth ◽  
K Srinivasa Reddy
Keyword(s):  
Comparative Study ◽  
Efficient Method ◽  
Catalytic Amount ◽  
Solvent Free ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Efficient Catalyst ◽  
Highly Efficient ◽  
Solvent Free Conditions ◽  
The Comparative Study

A simple and highly efficient method has been developed for the tetrahydropyranylation of alcohols by their reaction with 3,4-dihydro-2H-pyran (DHP) using a catalytic amount (0.01–1 mol%) of aluminium triflate under solvent-free conditions. The effect of various factors like temperature, amount of the catalyst, and molar ratio of substrates on the reaction conditions has also been studied. The comparative study of tetrahydropyranylation of benzyl alcohol using various catalysts including some reported ones shows the efficiency of this catalyst.Key words: tetrahydropyranylation, aluminium triflate, alcohols, catalysis.

Iron (III) chloride hexahydrate as a highly efficient catalyst for acetylation of protic nucleophiles with acetic anhydride under solvent-free conditions

2020 ◽  
Vol 07 ◽  
Author(s):  
Naoures Jamel Eddine ◽  
Fayçal Jennen ◽  
Yakdhane Kacem ◽  
Jamil Kraiem
Keyword(s):  
Acetic Anhydride ◽  
Room Temperature ◽  
Catalytic Amount ◽  
Solvent Free ◽  
Environmentally Benign ◽  
Efficient Catalyst ◽  
Highly Efficient ◽  
Solvent Free Conditions ◽  
Chloride Hexahydrate ◽  
New Methodologies

Background: Acetylation of protic nucleophiles is used to protect these functional groups. Most of the methods described in the literature use solvents, one equivalent or more of toxic bases or expensive and toxic catalysts. Therefore, new methodologies are still in demand, above all, greener and more economical procedures. Objective: An eco-efficient method developed for acetylation of alcohols, phenols, thiols, amines and carbohydrates, using acetic anhydride and a catalytic amount of the environmentally benign and inexpensive FeCl3.6H2O under solvent free conditions. Methods: Acetylation of a variety of protic nucleophiles was performed using 0.2 mol % of FeCl3.6H2O as the catalyst, and 1.2 equiv. as the acetylating agent at room temperature and under solvent free conditions. Results: Our procedure appears to be highly efficient and promoted rapid and quantitative acetylation under simple and minimum manipulation. Chromatography or recrystallization were generally not necessary for the purification of products. Conclusion: This eco-friendly protocol appears to be potentially universally applicable in organic design to protect protic nucleophiles and potentially scalable for industrial fields.

Rapid synthesis of homoallylic alcohol from aldehyde with allyltributylstannane under solvent-free conditions

2012 ◽  
Vol 90 (2) ◽  
pp. 167-172 ◽  
Author(s):  
Pranjal P. Bora ◽  
H. Atoholi Sema ◽  
Barisha Wahlang ◽  
Ghanashyam Bez
Keyword(s):  
Reaction Time ◽  
Phosphotungstic Acid ◽  
Catalytic Amount ◽  
Solvent Free ◽  
Reaction Conditions ◽  
Rapid Synthesis ◽  
Short Reaction Time ◽  
Solvent Free Conditions ◽  
Solvent Free Reaction

A catalytic amount (2 mol %) of phosphotungstic acid (PTA) is sufficient to synthesize homoallylic alcohol in excellent yields from aldehyde with allyltributylstannane upon grinding under solvent-free reaction conditions. Easy handling, very short reaction time, solvent-free reaction conditions, and aqueous workup free isolation protocol may make our method very useful for synthetic chemists.

A highly efficient, solvent-free and energy-effective method of cellulose acetylation

e-Polymers ◽  
2005 ◽  
Vol 5 (1) ◽  
Author(s):  
Abdelmajid Memmi ◽  
Robert Granet ◽  
Yves Champavier ◽  
Pierre Krausz
Keyword(s):  
Nmr Spectroscopy ◽  
Acetic Anhydride ◽  
1H Nmr ◽  
1H Nmr Spectroscopy ◽  
Room Temperature ◽  
Solvent Free ◽  
Highly Efficient ◽  
Solvent Free Conditions ◽  
Cellulose Acetates

AbstractAcetylation of cellulose by acetic anhydride was found to be catalysed quantitatively by iodine under solvent-free conditions at room temperature. Cellulose acetates were characterised by 1H NMR spectroscopy.

scholarly journals Friedel-Crafts acylation of 2-methoxynaphthalene with acetic anhydride catalyzed by phosphotungstic acid in ionic liquid

2019 ◽  
Vol 51 (2) ◽  
pp. 289-295
Author(s):  
Y. Guo ◽  
J. Sun ◽  
F. Guo ◽  
Yu. He ◽  
P. Chen
Keyword(s):  
Ionic Liquid ◽  
Reaction Time ◽  
Acetic Anhydride ◽  
Catalytic System ◽  
Phosphotungstic Acid ◽  
Significant Loss ◽  
Good Stability ◽  
Optimal Conditions ◽  
Reaction Conditions

The Friedel-Crafts acylation of 2-methoxynaphthalene (2-MN) with acetic anhydride (AA) was carried out in the ionic liquid (IL) butylpyridinium tetrafluoroborate ([BPy]BF4) using phosphotungstic acid (H3PW12O40) as the catalyst. The [BPy]BF4-mediated 2-MN acylation displays good conversion and selectivity towards 1-acyl-2-methoxynaphthalene (1-AC-2-MN), with 70.4% conversion of 2-MN and 96.4% selectivity to 1-AC-2-MN obtained under the optimal conditions. Owing to the rearrangement of 1-AC-2-MN, 6-acyl-2-methoxynaphthalene (6-AC-2-MN) can be detected after 1 h of reaction time, with the highest 6-AC-2-MN yield of 11.3% obtained under the examined reaction conditions. The system can be recycled and reused at least 6 times without significant loss of activity, indicating the good stability of the H3PW12O40/[BPy]BF4 catalytic system.

Highly efficient solvent-free acetylation of alcohols with acetic anhydride catalyzed by recyclable sulfonic acid catalyst (SBA-15–Ph–Pr–SO3H) — An environmentally benign method

2012 ◽  
Vol 90 (5) ◽  
pp. 464-468 ◽  
Author(s):  
Daryoush Zareyee ◽  
Abdollah Razaghi Ghadikolaee ◽  
Mohammad A. Khalilzadeh
Keyword(s):  
Acetic Anhydride ◽  
Sulfonic Acid ◽  
Acid Catalyst ◽  
Solvent Free ◽  
Environmentally Benign ◽  
Reaction Conditions ◽  
Experimental Procedure ◽  
Solvent Free Conditions ◽  
Reaction Cycles ◽  
Thermal Stable

The catalytic activity of highly thermal stable, hydrophobic, and complete heterogeneous propylsulfonic acid functionalized nanostructured SBA-15 for excellent acetylation of alcohols and phenols with acetic anhydride at ambient temperature in solvent-free conditions was examined under environmentally benign reaction conditions. The salient features of this protocol are the absence of solvent, a green experimental procedure, and simple reusability of the catalyst (at least five reaction cycles).

Zirconium(IV) 4-sulphophenylethyliminobismethylphosphonate as an efficient and reusable catalyst for one-pot synthesis of 3,4-dihydropyrimidones under solvent-free conditions

2011 ◽  
Vol 65 (6) ◽  
Author(s):  
Xin-Bin Yang ◽  
Xiang-Kai Fu ◽  
Yu Huang ◽  
Ren-Quan Zeng
Keyword(s):  
Catalytic Activity ◽  
Elemental Analysis ◽  
Biginelli Reaction ◽  
Significant Loss ◽  
Solvent Free ◽  
Reusable Catalyst ◽  
One Pot ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
Simple Filtration

AbstractZirconium(IV) 4-sulphophenylethyliminobismethylphosphonate (ZSBEDP) was prepared and characterised by elemental analysis, IR, TG-DSC, and XRD. ZSBEDP was found to be an efficient catalyst for the Biginelli reaction of aromatic aldehyde, ethyl acetoacetate, and urea or thiourea under solvent-free conditions so as to give 3,4-dihydropyrimidones in good to excellent yields. The catalyst can be separated by simple filtration and reused without significant loss of its catalytic activity.

Commercial ZrO2 as a new, efficient, and reusable catalyst for the one-step synthesis of quinolines in solvent-free conditions

2009 ◽  
Vol 87 (8) ◽  
pp. 1122-1126 ◽  
Author(s):  
Mona Hosseini-Sarvari
Keyword(s):  
Catalytic Activity ◽  
Carbonyl Compound ◽  
Significant Loss ◽  
Solvent Free ◽  
Reusable Catalyst ◽  
Efficient Catalyst ◽  
Solvent Free Conditions ◽  
One Step ◽  
The One ◽  
High Yields

Commercially available zirconia (ZrO2) is reported as an extremely efficient catalyst for the synthesis of quinolines. A one-step reaction of 2-aminoarylketones and a carbonyl compound (Friedlander reaction) took place under solvent-free conditions to afford the corresponding quinolines in good-to-high yields in the presence of ZrO2. Furthermore, the catalyst is reused several times without any significant loss of its catalytic activity.

Sign in / Sign up

Export Citation Format

Share Document