Hydrolysis of amides to carboxylic acids catalyzed by Nb2O5

2021 ◽  
Author(s):  
S. M. A. Hakim Siddiki ◽  
Md. Nurnobi Rashed ◽  
Abeda Sultana Touchy ◽  
Md. A. R. Jamil ◽  
Yuan Jing ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Catalytic System ◽  
Hydrolysis Reaction ◽  
Amide Hydrolysis ◽  
Hydrolysis Of

An efficient heterogeneous Nb2O5 catalytic system has been developed for industrially important and challenging amide hydrolysis reaction to carboxylic acid through cleavage of resonance stabilized amidic C–N bond.

Isocarbostyrils. II. The Conversion of 2-Methyl-4-acyl-5-nitroisocarbostyrils to 2-Substituted Indole-4-carboxylic Acids

1971 ◽  
Vol 49 (17) ◽  
pp. 2797-2802 ◽  
Author(s):  
D. E. Horning ◽  
G. Lacasse ◽  
J. M. Muchowski
Keyword(s):  
Sulfuric Acid ◽  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Alkaline Hydrolysis ◽  
Mannich Reaction ◽  
Reductive Cyclization ◽  
Acid Catalyzed ◽  
Acid Anhydrides ◽  
Hydrolysis Of ◽  
Derivatives Of

The sulfuric acid catalyzed acylation of 2-methyl-5-nitroisocarbostyril with carboxylic acid anhydrides gave the corresponding 4-acylated derivatives 3, which underwent reductive cyclization to 2-substituted derivatives of 4-methyl-1,3,4,5-tetrahydropyrrolo[4.3.2.de]isoquinolin-5-one (4). Alkaline hydrolysis of the six-membered lactam in 4 was accompanied by a retro-Mannich reaction to produce 2-substituted indole-4-carboxylic acids in about 40 % overall yield from 3.

Ribonucleosides of 3-amino- and 3,5-diaminopyrazole-4-carboxylic acid and their open-chain analogues: Synthesis and reactions

1986 ◽  
Vol 51 (7) ◽  
pp. 1512-1531 ◽  
Author(s):  
Maria K. Spassova ◽  
Antonín Holý ◽  
Milena Masojídková
Keyword(s):  
Carboxylic Acid ◽  
Acid Hydrolysis ◽  
Carboxylic Acids ◽  
Sodium Salt ◽  
Alkaline Hydrolysis ◽  
Trimethylsilyl Derivative ◽  
Open Chain ◽  
Silyl Derivatives ◽  
Hydrolysis Of

Bis(trimethylsilyl) derivative of ethyl 3-aminopyrazole-4-carboxylate (VI) and tris(trimethylsilyl) derivative of ethyl 3,5-diaminopyrazole-4-carboxylate (VII) on reaction with 2,3,5-tri-O-benzoyl-D-ribofuranolyl chloride and subsequent debenzoylation afforded the respective β-D-ribofuranosyl derivatives VIIIa and Xa. Their alkaline hydrolysis led to 1-(β-D-ribofuranosyl)-3-aminopyrazole-4-carboxylic acid (VIIIc) and 1-(β-D-ribofuranosyl)-3,5-diaminopyrazole-4-carboxylic acid (Xb). The esters VIIIa and Xa were not ammonolyzed under normal conditions. Contrary to nucleosidation of the silyl derivatives VI and VII, sodium salt of ethyl 3-aminopyrazole-4-carboxylate was alkylated with 4-chloromethyl-2,2-dimethyl-1,3-dioxolane (XI) or 5-(p-toluenesulfonyloxy)-1,3-dioxane (XVIIb) to give a mixture of the N-isomeric derivatives XIIIa, XIXa and XIIa, XVIIIa, respectively; sodium salt of the 3,5-diamino derivative V reacted with these synthons under formation of the corresponding compounds XIIIb and XXa. Subsequent alkaline and acid hydrolysis of XIIa and XIIIb gave the open-chain analogs of nucleosides XV and XVI. The N-(1,3-dioxan-5-yl) derivatives XVIIIc and XXa resisted acid hydrolysis, giving rise only to carboxylic acids XVIIIb and XXb.

scholarly journals Synthesis of higher carboxylic acids from ethers, CO2 and H2

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Ying Wang ◽  
Qingli Qian ◽  
Jingjing Zhang ◽  
Bernard Baffour Asare Bediako ◽  
Zhenpeng Wang ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Catalytic System ◽  
Acid Synthesis ◽  
Alternative Strategy ◽  
Mechanistic Study ◽  
Rwgs Reaction ◽  
Alkyl Iodides

AbstractSynthesis of higher carboxylic acids using CO2 and H2 is of great importance, because CO2 is an attractive renewable C1 resource and H2 is a cheap and clean reductant. Herein we report a route to produce higher carboxylic acids via reaction of ethers with CO2 and H2. We show that the reaction can be efficiently catalyzed by an IrI4 catalyst with LiI as promoter at 170 °C, 5 MPa of CO2 and 2 MPa of H2. The catalytic system applies to various ether substrates. The mechanistic study indicates that the ethers are converted to olefins, which are further transformed into alkyl iodides. The higher carboxylic acids are produced by carbonylation of alkyl iodides with CO generated in situ via RWGS reaction. This report offers an alternative strategy of higher carboxylic acid synthesis and CO2 transformation.

Investigation of Readily Available Chiral Compounds for Preparative Scale Resolutions

1987 ◽  
Vol 40 (10) ◽  
pp. 1641 ◽  
Author(s):  
CC Duke ◽  
RJ Wells
Keyword(s):  
Carboxylic Acid ◽  
Carboxylic Acids ◽  
Preparative Scale ◽  
Chiral Compounds ◽  
Optically Pure ◽  
Hydrolysis Of

Diastereoisomeric esters were formed by reaction of racemic carboxylic acids with the readily available hydroxy lactone derivatives, 2,3-O-isopropylidene-D(+)-ribono-l,4-lactone, D(-)-2- hydroxy-3,3-dimethylbutyro-1,4-lactone (D(-)-pantolactone) and 1,2-O-isopropylidene-(+)-α-D-glucofuranurono-6,3-lactone. In all cases separation of the diastereoisomeric esters was achieved by crystallization and/or chromatography. Purity of the diastereoisomers could be determined by h.p.l.c. or by 1H n.m.r. Hydrolysis under mild basic conditions followed by treatment with acid gave optically pure carboxylic acids. The facile separation by crystallization and/or chromatography of diastereoisomers prepared from racemic endo-1,4,5,6,7,7-hexachlorobicyclo[2.2.l]hept-5-ene-2-carboxylic acid suggested that the resolved acid may be useful as a resolving agent. This was shown by separation of diastereoisomers formed from the resolved acid and racemic 1-(3′-phenoxyphenyl)prop-2- yn-1-ol and racemic 1-cyano-1-(3'-phenoxypheny1)methanol respectively. Optically pure 1-(3'-phenoxypheny1)prop-2-yn-1-ol was obtained by hydrolysis of the separated diastereoisomers.

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.

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.

Carboxylic acid-catalysed hydrolysis of rhamnogalacturonan in subcritical water media

2021 ◽  
pp. 105268
Author(s):  
Carla S. Valdivieso Ramirez ◽  
Feral Temelli ◽  
Marleny D.A. Saldaña
Keyword(s):  
Carboxylic Acid ◽  
Subcritical Water ◽  
Water Media ◽  
Hydrolysis Of
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