Suggested Improvement in the Ing−Manske Procedure and Gabriel Synthesis of Primary Amines:  Kinetic Study on Alkaline Hydrolysis ofN-Phthaloylglycine and Acid Hydrolysis ofN-(o-Carboxybenzoyl)glycine in Aqueous Organic Solvents

1996 ◽  
Vol 61 (23) ◽  
pp. 8063-8068 ◽  
Author(s):  
M. Niyaz Khan
Keyword(s):  
Kinetic Study ◽  
Acid Hydrolysis ◽  
Organic Solvents ◽  
Alkaline Hydrolysis ◽  
Primary Amines

SYNTHÈSES DE DÉRIVÉS DE LA LYSINE

1962 ◽  
Vol 40 (8) ◽  
pp. 1626-1631 ◽  
Author(s):  
Louis-Marie Babineau ◽  
Louis Berlinguet
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Barium Hydroxide ◽  
Primary Amines ◽  
Gaseous Ammonia ◽  
Hydrolysis Of

New N-ε-substituted lysines have been synthetized as follows: by condensing 5-δ-bromobutylhydantoin with different primary amines, 5-δ-alkylaminobutylhydantoins were obtained, the alkaline hydrolysis of which gave the corresponding N-ε-substituted lysines. N-α-Substituted hexahomoserines have also been prepared by acid hydrolysis of the reaction product between α,ε-dihydroxycaproic nitrile and primary amines. 5-Amino-5-carboxypentane sulphonamide has been prepared in the following way: 5-δ-bromobutylhydantoin was reacted with thiourea, and the resulting isothiouronium salt was oxidized with chlorine. Gaseous ammonia was then bubbled through an ethereal suspension of the 5-δ-chlorosulphonyl butylhydantoin and the resulting sulphonamide was hydrolyzed under pressure with barium hydroxide. 5-Amino-5-carboxypentane sulphonamide was then isolated and crystallized.

Kinetic Study of Hydrolysis of Benzoates. Part XXVI. Variation of the Substituent Effect with Solvent in Alkaline Hydrolysis of Substituted Alkyl Benzoates

2006 ◽  
Vol 71 (11-12) ◽  
pp. 1557-1570 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Ilmar A. Koppel
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Rate Constants ◽  
Substituent Effect ◽  
Substituent Effects ◽  
Alkyl Substituent ◽  
Solvent Parameters ◽  
Substituent Constants ◽  
Hydrolysis Of ◽  
Main Factor

The second-order rate constants k2 (dm3 mol-1 s-1) for the alkaline hydrolysis of substituted alkyl benzoates C6H5CO2R have been measured spectrophotometrically in aqueous 0.5 M Bu4NBr at 50 and 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH, CH2C6H5, CH2CH2Cl, CH2CH2OCH3, CH2CH3) and in aqueous 5.3 M NaClO4 at 25 °C (R = CH3, CH2Cl, CH2CN, CH2C≡CH). The dependence of the alkyl substituent effects on different solvent parameters was studied using the following equations:      ∆ log k = c0 + c1σI + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆EσI + c7∆YσI + c8∆PσI     ∆ log k = c0 + c1σ* + c2EsB + c3∆E + c4∆Y + c5∆P + c6∆Eσ* + c7∆Yσ* + c8∆Pσ* .  ∆ log k = log kR - log kCH3. σI and σ* are the Taft inductive and polar substituent constants. E, Y and P are the solvent electrophilicity, polarity and polarizability parameters, respectively. In the data treatment ∆E = ES - EH2O , ∆Y = YS - YH2O , ∆P = PS - PH2O were used. The solvent electrophilicity, E, was found to be the main factor responsible for changes in alkyl substituent effects with medium. When σI constants were used, variation of the polar term of alkyl substituents with the solvent electrophilicity E was found to be similar to that observed earlier for meta and para substituents, but twice less when σ* constants were used. The steric term for alkyl substituents was approximately independent of the solvent parameters.

Kinetic Study of Hydrolysis of Benzoates. Part XXV. Ortho Substituent Effect in Alkaline Hydrolysis of Phenyl Esters of Substituted Benzoic Acids in Water

2006 ◽  
Vol 71 (1) ◽  
pp. 107-128 ◽  
Author(s):  
Vilve Nummert ◽  
Mare Piirsalu ◽  
Vahur Mäemets ◽  
Ilmar Koppel
Keyword(s):  
Acid Hydrolysis ◽  
Alkaline Hydrolysis ◽  
Substituent Effect ◽  
Ethyl Esters ◽  
Benzoic Acids ◽  
Neat Water ◽  
Substituted Benzoic Acids ◽  
Hydrolysis Of Esters ◽  
Hydrolysis Of

The second-order rate constants k2 for alkaline hydrolysis of phenyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2C6H5 (X = H, 3-Cl, 3-NO2, 3-CH3, 4-NO2, 4-Cl, 4-F, 4-CH3, 4-OCH3, 4-NH2, 2-NO2, 2-CN, 2-F, 2-Cl, 2-Br, 2-I, 2-CH3, 2-OCH3, 2-CF3, 2-NH2), and of substituted phenyl esters of benzoic acid, C6H5CO2C6H4-X (X = 2-I, 2-CF3, 2-C(CH3)3, 4-Cl, 4-CH3, 4-OCH3, 4-NH2), have been measured spectrophotometrically in water at 25 °C. The substituent effect in alkaline hydrolysis of phenyl esters of para-substituted benzoic acids, similar to that for ethyl esters of para-substituted benzoic acids, was found to be precisely described by the Hammett relationship (ρ = 1.7 in water). The log k value for alkaline hydrolysis of phenyl and ethyl esters of meta-, para- and ortho-substituted benzoic acids, X-C6H4CO2R, was nicely correlated with log km,p,ortho = log ko + (ρ)m,pσ + (ρI)orthoσI + (ρ°R)orthoσ°R + δorthoEsB where σ, σI, σ°R are the Hammett polar, Taft inductive and Taft resonance (σ°R = σ° - σI) substituent constants, respectively. EsB is the steric scale for ortho substituents calculated on the basis of the log k values for the acid hydrolysis of ortho- substituted phenyl benzoates in water owing to the ortho substituent in the phenyl of phenyl benzoates. In water, the main factors responsible for changes in the ortho substituent effect in alkaline hydrolysis of phenyl and ethyl esters of ortho-substituted benzoic acids, X-C6H4CO2R, were found to be the inductive and steric factors while the role of the resonance term was negligible ((ρ°R)ortho ca. 0.3). In alkaline hydrolysis of substituted benzoates in neat water, the ortho inductive effect appeared to be 1.5 times and steric influence 2.7 times higher than the corresponding influences from the ortho position in the phenyl of phenyl benzoates. The contributions of the steric effects in alkaline hydrolysis of esters of ortho-substituted benzoic acids was found to be approximately the same as in acid hydrolysis of esters of ortho-substituted benzoic and acid esterification of ortho-substituted benzoic acids.

A kinetic study of the acid autoxidation of tryptophan

1972 ◽  
Vol 25 (10) ◽  
pp. 2139 ◽  
Author(s):  
M Stewart ◽  
CH Nicholls
Keyword(s):  
Free Radical ◽  
Amino Acid ◽  
Kinetic Study ◽  
Acid Hydrolysis ◽  
Soda Glass ◽  
Glass Containers ◽  
Hydrolysis Of

The decomposition of tryptophan in aqueous HC1 at 100�C has been shown to proceed by a free-radical autoxidation mechanism. The acid functions by protonating the amino acid at either the 1- or 3-positions prior to autoxidation and so 1-methyltryptophan is also decomposed under these conditions. Impurities present in the soda glass containers used are shown to be responsible for the initiation of the reaction. The decomposition of tryptophan during the acid hydrolysis of proteins is considered in the light of these results.

Kinetic study on the alkaline hydrolysis of Co(NH3)5O2C2Cl32+ and Co(NH3)5O2C2Cl2H2+

1967 ◽  
Vol 6 (2) ◽  
pp. 379-382 ◽  
Author(s):  
Neil S. Angerman ◽  
Robert B. Jordan
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Hydrolysis Of

A kinetic study of the depolymerisation of poly(ethylene terephthalate) by phase transfer catalysed alkaline hydrolysis

2009 ◽  
Vol 84 (1) ◽  
pp. 92-99 ◽  
Author(s):  
R. López-Fonseca ◽  
M. P. González-Marcos ◽  
J. R. González-Velasco ◽  
J. I. Gutiérrez-Ortiz
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Ethylene Terephthalate ◽  
Phase Transfer ◽  
Poly Ethylene Terephthalate ◽  
Poly Ethylene

Kinetic study of microwave-assisted alkaline hydrolysis of Jatropha curcas oil

2016 ◽  
Author(s):  
Nur’aini Raman Yusuf ◽  
Ruzaimah Nik Mohamad Kamil ◽  
Suzana Yusup
Keyword(s):  
Kinetic Study ◽  
Alkaline Hydrolysis ◽  
Jatropha Curcas ◽  
Jatropha Curcas Oil ◽  
Microwave Assisted ◽  
Hydrolysis Of
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