scholarly journals Hemiacetal Ester Exchanges, Study of Reaction Conditions and Mechanistic Pathway

Reactions ◽  
2020 ◽  
Vol 1 (2) ◽  
pp. 89-101
Author(s):  
David Boucher ◽  
Jeppe Madsen ◽  
Nicolas Caussé ◽  
Nadine Pébère ◽  
Vincent Ladmiral ◽  
...  
Keyword(s):  
Exchange Rate ◽  
Carboxylic Acid ◽  
Exchange Reaction ◽  
Carboxylic Acids ◽  
Vinyl Ether ◽  
Dihydrogen Phosphate ◽  
Reaction Conditions ◽  
Kinetics Studies ◽  
Mechanistic Pathway ◽  
Reaction Proceeds

A range of hemiacetal esters were synthesized by the reaction between carboxylic acids and butyl vinyl ether using n-dodecyl dihydrogen phosphate as catalyst. Specifically, nonanoic, propionic, acrylic, sebacic, and fumaric acids were used as substrates to prepare the corresponding hemiacetalesters. These compounds were used as model molecules to demonstrate the ability of hemiacetal ester functional groups to undergo the exchange reaction in the presence of weak carboxylic acids without any catalyst. Kinetics studies examined the eect of the carboxylic acid concentration on the exchange rate, and revealed that the exchange reaction proceeds through an associative mechanism.

scholarly journals Novel sustainable synthesis of vinyl ether ester building blocks, directly from carboxylic acids and the corresponding hydroxyl vinyl ether, and their photopolymerization

RSC Advances ◽  
2018 ◽  
Vol 8 (44) ◽  
pp. 24716-24723 ◽  
Author(s):  
Maja Finnveden ◽  
Sara Brännström ◽  
Mats Johansson ◽  
Eva Malmström ◽  
Mats Martinelle
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Vinyl Ether ◽  
Building Blocks ◽  
Ether Ester

Synthesis of bifunctional vinyl ether ester monomers directly from the corresponding alcohol and carboxylic acid.

One Pot Conversion of Carboxylic Acid to Ketone Using Trimethylsilyl Chloride

2020 ◽  
Vol 07 ◽  
Author(s):  
Habtamu Gelaw Mekonnen ◽  
Samaresh Jana
Keyword(s):  
Organic Chemistry ◽  
Natural Products ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Organometallic Reagent ◽  
Trimethylsilyl Ester ◽  
Reaction Conditions ◽  
One Pot ◽  
Simple Process ◽  
Organolithium Reagents

Background: Ketone is abundant in many natural products and in pharmaceuticals. It is believed to be one of the important functional groups in organic chemistry. Till date,several research approaches have been made to access ketone from a readily available starting materials. One such notable transformation consists of the conversion of carboxylic acid to the corresponding ketone in a one pot manner. Objective: We aimed to develop a simple one pot reaction for the conversion of carboxylic acid to ketone. This reaction could be useful to convert all types of carboxylic acid to ketone in a facile manner. Methods: In this procedure, a carboxylic acid has been converted to the corresponding trimethylsilyl ester using trimethylsilyl chloride in the presence of a base. A suitable organometallic reagent can interact with the ester formed at 20°C to produce the corresponding ketone. Results: Under the optimized reaction conditions, various aromatic, aliphatic and heteroaromatic carboxylic acids have been converted to the corresponding ketones using organolithium reagents, in a one pot manner. Moderate to good yields of the desired ketones were observed in most of the transformations. Conclusion: Conversion of carboxylic acid to ketone has been reported in a one pot fashion, where carboxylic acid has been transformed to its silyl ester. Organolithium reagents were used as nucleophile for our reaction purpose, whereas the organomagnesium reagents were not useful for this transformation. Aliphatic, aromatic and heteroaromatic carboxylic acids have been converted to the ketones following a simple process.

Exploration of Mesyl Chloride in a One Pot Conversion of Carboxylic Acids to Ketones

2020 ◽  
Vol 7 (3) ◽  
pp. 242-247
Author(s):  
Habtamu Gelaw Mekonnen ◽  
Debasis Sahoo ◽  
Samaresh Jana ◽  
Sanjoy Kumar Maji
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Functional Group ◽  
Reaction Times ◽  
Mixed Anhydride ◽  
Organometallic Reagent ◽  
Reaction Conditions ◽  
One Pot ◽  
Organometallic Reagents ◽  
Organolithium Reagents

Background: Due to the ubiquitous nature of the ketone functionality, it is considered an important functional group in organic chemistry. Hence, the synthesis of ketones from readily available starting materials is an important chemical transformation in organic synthesis. Consequently, several research efforts have been reported in the literature for the transformation of carboxylic acids to ketones in a one-pot synthesis. However, some of the procedures have limitations, such as long reaction times, harsh reaction conditions, and usage of expensive metal catalysts. Thus, a simple and convenient one-pot conversion of carboxylic acids to ketones remains desirable. Objective: We intended to develop a simple and convenient one-pot methodology for the synthesis of ketones from carboxylic acids. Our objective was to build up a carboxylic acid-based chemical template where various types of organometallic reagents can interact to produce the desired ketone. Methods: In this procedure, a carboxylic acid was converted to a mixed anhydride using mesyl chloride in the presence of a base. This mixed anhydride was then reacted with a suitable organometallic reagent at -20°C to obtain the desired ketone. The reaction was performed in a one-pot fashion. Results: Under the optimized reaction conditions, various aromatic and heteroaromatic carboxylic acids were converted to the corresponding ketones using organolithium and organomagnesium reagents with short reaction times. Moderate to good yields of the desired ketones were observed in many of these transformations. Conclusion: A simple and convenient one-pot method for the conversion of carboxylic acids to ketones has been reported. Specifically, various aromatic and `heteroaromatic carboxylic acids have been converted to the corresponding ketones in moderate to good yields. Organomagnesium and organolithium reagents were used as nucleophiles for this reaction.

Orthoamide, LVIII . Kondensationsreaktionen von CH2-aciden Verbindungen mit Orthoamiden von Carbonsäuren und Alkincarbonsäuren / Orthoamides, LVIII . Condensation Reactions of CH2-Acidic Compounds with Orthoamides of Carboxylic Acids and Alkyne Carboxylic Acids

2002 ◽  
Vol 57 (4) ◽  
pp. 399-419 ◽  
Author(s):  
Willi Kantlehner ◽  
Erwin Haug ◽  
Rüdiger Stieglitz ◽  
Wolfgang Frey ◽  
Ralf Kress ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Carboxylic Acid ◽  
Exchange Reaction ◽  
Carboxylic Acids ◽  
Benzoyl Chloride ◽  
Bond Distance ◽  
Condensation Reactions ◽  
Acidic Compounds ◽  
Anion Exchange Reaction ◽  
Guanidinium Salt

The orthoamide derivatives 1s and 2e were prepared from the guanidinium salt 7a and the appropriate carbanions. Cleavage of the orthoamide 2e with benzoyl chloride affords the amidinium salt 10a, which can be transformed into the amidinium salt 10b by an anion exchange reaction. The enamines 11a-i, 12a-c, 13a, b, 14a-c, 15a, b, 16, 17a, b, 18a, b, 19a, b, 20 were prepared by condensation of CH2-acidic compounds with the carboxylic acid orthoamides 2a-j. The orthoamide 2d reacts with 1-nitropropane to give the amidinium salt 27a which is transformed into the salt 27b. From benzyl cyanide and orthoamides 2g, i the enamines 30 and 32 were obtained. Similar condensation reactions were performed with the orthoamides of alkyne carboxylic acids 1b, 1c, 1d, 1e, 1p, 1s, giving the push-pull-butadiene derivatives 35a-f, 36a-f, 37a-j, 38a, b, 39a, b, 40a, b. Crystal structure analyses of the butadiene derivatives 37a, 39a, b, 40a, b and 42 were performed, showing that in 37a, 39b, 40a, b by far the shortest bond distance is between C-2 and C-3 of the butadiene system. In 39a the bonds between C1-C2, C2-C3 and C3-C4 are nearly of equal length, whereas in the 1,3-diene unit of 42 the shortest bonds are between C1-C2 and C3-C4.

scholarly journals Steric and Electronic Effects in the Synthesis and Regioselective Hydrolysis of Unsymmetrical Imides

2015 ◽  
Vol 68 (12) ◽  
pp. 1854 ◽  
Author(s):  
Jing Shang ◽  
Aysa Pourvali ◽  
James R. Cochrane ◽  
Craig A. Hutton
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Trifluoroacetic Acid ◽  
Coupling Reaction ◽  
Pivalic Acid ◽  
Electronic Effects ◽  
Subsequent Hydrolysis ◽  
Reaction Proceeds ◽  
Hydrolysis Of ◽  
Regioselective Hydrolysis

The AgI-promoted coupling reaction of thioamides and carboxylic acids is shown to be a useful method for the generation of unsymmetrical imides. The reaction proceeds efficiently with unhindered and electron-rich or neutral coupling partners, but not with hindered thioamides (such as thiopivalamides) or electron deficient thioamides (such as trifluorothioacetamides). Intriguingly, thioformamides are also ineffective coupling partners, despite having minimal steric or electronic influence. Hindered carboxylic acid coupling partners (such as pivalic acid) are tolerated, but electron deficient acids, such as trifluoroacetic acid, are ineffective coupling partners. Furthermore, an interplay of both steric and electronic effects is observed in the subsequent hydrolysis of unsymmetrical imides. Imides with a dimethoxybenzoyl group give high regioselectivity upon hydrolysis, favouring cleavage of the distal acyl group. Imides with a p-nitrobenzoyl or pivaloyl group give reversed selectivity, favouring cleavage of the proximal acyl group.

scholarly journals Palladium catalyzed oxidative aminations and oxylations: where are we?

2016 ◽  
Vol 88 (4) ◽  
pp. 381-389 ◽  
Author(s):  
Mélanie M. Lorion ◽  
Julie Oble ◽  
Giovanni Poli
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Product Formation ◽  
Sigmatropic Rearrangement ◽  
Reaction Pathways ◽  
Reaction Conditions ◽  
Initial Substrate ◽  
Palladium Catalyzed ◽  
Oxidative Acetoxylation

AbstractSelective product formation in the Pd-catalyzed cyclization of unsaturated amide and carboxylic acid derivatives is an intriguing and challenging task. We recently discovered that the oxidative intramolecular Pd(II)-catalyzed amination or oxylation of unsaturated N-sulfonyl carbamates, N-sulfonyl carboxamides and carboxylic acids takes place through the involvement of cyclic (usually, 5- or 6-membered) aminopalladated (AmPIs) or oxypalladated (OxPI) intermediates. Such cyclic intermediates can undergo a variety of transformations such as distocyclic β-H elimination, oxidative acetoxylation or intramolecular carbopalladation, depending upon the substrate and/or the reaction conditions. In the absence of appropriate reaction pathways, the cyclic nucleopalladated intermediates (NuPIs) simply engage in an inconsequential equilibrium with the initial substrate and other transformations occur such as allylic C–H activation or, in the particular case of allyl carbamates, [3,3]-sigmatropic rearrangement.

Ketones from Nickel-Catalyzed Decarboxylative, Non-Symmetric Cross-Electrophile Coupling of Carboxylic Acid Esters

2019 ◽  
Author(s):  
Jiang Wang ◽  
Brian P. Cary ◽  
Peyton Beyer ◽  
Samuel H. Gellman ◽  
Daniel Weix
Keyword(s):  
Carboxylic Acid ◽  
Solid Support ◽  
Reaction Conditions ◽  
Decarboxylative Coupling ◽  
New Strategy ◽  
The Cross ◽  
Acyl Donors ◽  
Acid Esters

A new strategy for the synthesis of ketones is presented based upon the decarboxylative coupling of N-hydroxyphthalimide (NHP) esters with S-2-pyridyl thioesters. The reactions are selective for the cross-coupled product because NHP esters act as radical donors and the thioesters act as acyl donors. The reaction conditions are general and mild, with over 40 examples presented, including larger fragments and the 20-mer peptide Exendin(9-39) on solid support.

Synthesis of 3-(Cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8- carboxylic Acids Via an Efficient Three-component Condensation Reaction between Cyclohexylisocyanide and 2-Aminopyridine-3-carboxylic Acid in the Presence of Aromatic Aldehyde

2018 ◽  
Vol 21 (4) ◽  
pp. 298-301 ◽  
Author(s):  
Ghasem Marandi
Keyword(s):  
Biological Sciences ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
High Performance ◽  
Condensation Reaction ◽  
Aromatic Aldehydes ◽  
New Materials ◽  
One Pot ◽  
High Yields ◽  
Benzaldehyde Derivatives

Aim and Objective: The reaction of cyclohexylisocyanide and 2-aminopyridine-3- carboxylic acid in the presence of benzaldehyde derivatives in ethanol led to 3-(cyclohexylamino)-2- arylimidazo[1,2-a]pyridine-8-carboxylic acids in high yields. In a three component condensation reaction, isocyanide reacts with 2-aminopyridine-3-carboxylic acid and aromatic aldehydes without any prior activation. Material and Methods: The synthesized products have stable structures which have been characterized by IR, 1H, 13C and Mass spectroscopy as well as CHN-O analysis. Results: In continuation of our attempts to develop simple one-pot routes for the synthesis of 3- (cyclohexylamino)-2-arylimidazo[1,2-a]pyridine-8-carboxylic acids, aromatic aldehydes with divers substituted show a high performance. Conclusion: In conclusion, this study introduces the art of combinatorial chemistry using a simple one-pot procedure for the synthesis of new materials which are interesting compounds in medicinal and biological sciences.

scholarly journals Propylphosphonic acid anhydride–mediated amidation of Morita–Baylis–Hillman–derived indolizine-2-carboxylic acids

2021 ◽  
pp. 174751982098715
Author(s):  
Khethobole C Sekgota ◽  
Michelle Isaacs ◽  
Heinrich C Hoppe ◽  
Ronnett Seldon ◽  
Digby F Warner ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Coupling Agent ◽  
Methyl Esters ◽  
Acid Anhydride

Propylphosphonic acid anhydride has been successfully used as a coupling agent in the synthesis of a series of indolizine-2-carboxamido derivatives from indolizine-2-carboxylic acid and its 3-acetylated analogue. The acid substrates were obtained by saponification of the corresponding methyl esters produced, in turn, selectively and efficiently, by time-controlled cyclisation of a single Morita–Baylis–Hillman adduct. Various amino and hydrazino compounds with medicinal potential have been used to prepare indolizine-2-carboxamido and hydrazido derivatives.

Sign in / Sign up

Export Citation Format

Share Document