ChemInform Abstract: An Efficient Esterification Reaction Between Equimolar Amounts of Free Carboxylic Acids and Alcohols by the Combined Use of Octamethylcyclotetrasiloxane and a Catalytic Amount of Titanium(IV) Chloride Tris(trifluoromethanesulfonate).

ChemInform ◽  
2010 ◽  
Vol 26 (29) ◽  
pp. no-no
Author(s):  
J. IZUMI ◽  
I. SHIINA ◽  
T. MUKAIYAMA
Keyword(s):  
Carboxylic Acids ◽  
Catalytic Amount ◽  
Esterification Reaction ◽  
Combined Use

Reversing Reactivity: Stereoselective Desulfurative β-O-Glycosylation of Anomeric Thiosugars with Carboxylic Acids Under Copper or Cobalt Catalysis

2019 ◽  
Author(s):  
Samir Messaoudi ◽  
Nedjwa Bennai ◽  
Amelie Chabrier ◽  
Maha Fatthalla ◽  
Expédite Yen-Pon ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Late Stage ◽  
Catalytic Amount ◽  
Broad Scope ◽  
Wide Range ◽  
Glycosylation Reaction

We have discovered a new mode of reactivity of 1-thiosugars in the presence of Cu(II) or Co(II) for a stereoselective <i>O</i>-glycosylation reaction. The process involves the use of a catalytic amount of Cu(acac)2 or Co(acac)2 and Ag2CO3 as an oxidant in α,α,α-trifluorotoluene (TFT). Moreover, this protocol turned out to have a broad scope, allowing to prepare a wide range of com-plex substituted <i>O</i>-glycoside esters in good to excellent yields with an exclusive β-selectivity. The late-stage modification of phar-maceuticals by this method was also demonstrated.

A New and Efficient Esterification Reaction via Mixed Anhydrides by the Promotion of a Catalytic Amount of Lewis Acid

1993 ◽  
Vol 66 (5) ◽  
pp. 1516-1527 ◽  
Author(s):  
Mitsutomo Miyashita ◽  
Isamu Shiina ◽  
So Miyoshi ◽  
Teruaki Mukaiyama
Keyword(s):  
Lewis Acid ◽  
Catalytic Amount ◽  
Esterification Reaction ◽  
Mixed Anhydrides

Studies on Iron-Catalyzed Aerobic Oxidation of Benzylic Alcohols to Carboxylic Acids

Synthesis ◽  
2018 ◽  
Vol 50 (08) ◽  
pp. 1629-1639 ◽  
Author(s):  
Shengming Ma ◽  
Xingguo Jiang
Keyword(s):  
Carboxylic Acids ◽  
Large Scale ◽  
Aerobic Oxidation ◽  
Catalytic Amount ◽  
Steric Effects ◽  
Benzylic Alcohols ◽  
Academic Laboratory ◽  
Electron Donating Groups ◽  
Electronic And Steric Effects ◽  
Comprehensive Study

A comprehensive study on aerobic oxidation of benzylic alcohols­ to carboxylic acids with a catalytic amount each of Fe(NO3)3·9H2O, TEMPO, and KCl is conducted. Various synthetically useful functional groups are well tolerated in the reaction. Distinct electronic and steric effects are observed in the reaction: electron-withdrawing groups accelerate the reaction while electron-donating groups make the reaction slower, and ortho-substituted substrates react slower than meta-substituted substrates. Several large-scale reactions (100 mmol) are conducted using a slow air flow of 30 mL/min to demonstrate the practicality of this method in an academic laboratory.

Ag/CdS Nanocomposite: An Efficient Recyclable Catalyst for the Synthesis of Novel 8-Aryl-8H-[1,3]dioxolo[4,5-g]chromene-6-carboxylic Acids under Mild Reaction Conditions

2018 ◽  
Vol 21 (5) ◽  
pp. 323-328 ◽  
Author(s):  
Shahrzad Abdolmohammadi ◽  
Seyed Reza Rasouli Nasrabadi ◽  
Ahmad Seif ◽  
Narges Elmi Fard
Keyword(s):  
Carboxylic Acids ◽  
Condensation Reaction ◽  
Sol Gel ◽  
Aqueous Media ◽  
Chemical Properties ◽  
Catalytic Amount ◽  
13C Nmr Spectroscopy ◽  
Biological Properties ◽  
Recyclable Catalyst ◽  
Reaction Conditions

Aim and Objective: Chromene derivatives are privileged heterocyclic systems that exhibit various types of biological properties such as antioxidant, anticancer, antimicrobial, hypotensive, and local anesthetic. Cadmium sulfide nanoparticles (CdS NPs) as an efficient heterogeneous catalyst is used in various organic transformations because of its certain unique and unusual physico-chemical properties. The effectiveness of catalytic activity of CdS NPs can be improved due to the combined effect of Ag particles. Results: Ag/CdS nanocomposite is a readily available, recyclable, and non-toxic catalyst used for the highly efficient synthesis of novel 8-aryl-8H-[1,3]dioxolo[4,5-g]chromrne-6-carboxylic acids. This reaction is conveniently performed under mild reaction conditions. All synthesized compounds were well characterized by their satisfactory elemental analyses, IR, 1H and 13C NMR spectroscopy. The synthesized catalyst was fully characterized by XRD, SEM, and EDX techniques. Materials and Methods: The present methodology focuses on the condensation reaction of arylmethylidenepyruvic acids with 3,4-methylenedioxyphenol, using a catalytic amount of Ag/CdS nanocomposite (15 mol%) in aqueous media at room temperature to afford 8-aryl-8H-[1,3]dioxolo [4,5-g]chromrne-6-carboxylic acids in high yields (90-97%) within short reaction times (2-4 h). The Ag/CdS nanocomposite was also prepared by an ultrasonic-assisted sol-gel method. Conclusion: In conclusion, we have successfully synthesized novel 8-aryl-8H-[1,3]dioxolo[4,5- g]chromrne-6-carboxylic acid derivatives by the Ag/CdS nanocomposite catalyzed cyclocondensation reaction of arylmethylidenepyruvic acids with 3,4-methylenedioxyphenol under mild reaction conditions. Environmentally benign procedure, high to excellent yields of products, simplicity of operation, and use of readily available and recyclable catalyst are the advantages of this new practical reaction.

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