An E1cB mechanism for the alkaline hydrolysis of thiolesters of fluorene-9-carboxylic acid: effect of ester conjugate base structure on differential eliminative reactivity of oxygen and sulphur nucleofuges

1982 ◽  
pp. 1467 ◽  
Author(s):  
Manoochehr Alborz ◽  
Kenneth T. Douglas ◽  
Fouad M. Said
Keyword(s):  
Carboxylic Acid ◽  
Alkaline Hydrolysis ◽  
Acid Effect ◽  
Hydrolysis Of ◽  
Conjugate Base ◽  
Base Structure

Thiohydantoins. XI Kinetic Studies of the Alkaline Hydrolysis of 1-Acyl-2-thiohydantoins

1972 ◽  
Vol 50 (23) ◽  
pp. 3780-3788 ◽  
Author(s):  
Wayne I. Congdon ◽  
John T. Edward
Keyword(s):  
Carboxylic Acid ◽  
Alkaline Solution ◽  
Alkaline Hydrolysis ◽  
Ground State ◽  
Kinetic Studies ◽  
Steric Effects ◽  
Hydroxide Ion ◽  
Entropy Of Activation ◽  
Hydrolysis Of ◽  
Conjugate Base

1-Acyl-2-thiohydantoins ionize in alkaline solution (pK ∼ 7). In solutions more alkaline than pH > 11 they are rapidly hydrolyzed to 2-thiohydantoin and a carboxylic acid, by attack of a hydroxide ion on the conjugate base of the 1-acyl-2-thiohydantoin. Possible mechanisms to accord with the entropy of activation, which is less negative than usual for base-catalyzed amide hydrolyses, are discussed. 1-Benzoyl-2-thiohydantoin hydrolyzes more rapidly than 1-acetyl-2-thiohydantoin, possibly because the ground state of the former molecule is destabilized by steric effects.

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.

Studies on the BAL2 mechanism for ester hydrolysis

1993 ◽  
Vol 71 (11) ◽  
pp. 1841-1844 ◽  
Author(s):  
Judy E. Douglas ◽  
Grant Campbell ◽  
Donald C. Wigfield
Keyword(s):  
Spectral Analysis ◽  
Carboxylic Acid ◽  
Alkaline Hydrolysis ◽  
Ester Hydrolysis ◽  
Mass Spectral Analysis ◽  
Mass Spectral ◽  
Hydrolysis Of

The preparation and alkaline hydrolysis of 18O-methyl 2,2-dimethylpropanoate and 18O-methyl triphenylacetate are reported. From mass spectral analysis of the carboxylic acid products, it is concluded that the former substrate is hydrolyzed exclusively by the BAC2 mechanism, whereas the latter substrate proceeds 95% by the BAC2 mechanism and 5% by the BAL2 mechanism. The balance between these two mechanisms is discussed.

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.

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