N-Aminopyrimidines: The Isomerization of 1-Aminobarbituric Acids to 2-(5-Oxo-4,5-dihydro-1H-1,2,4-triazol-3-yl) Aliphatic Acids

1979 ◽  
Vol 32 (1) ◽  
pp. 161 ◽  
Author(s):  
NW Jacobsen ◽  
BL McCarthy ◽  
S Smith
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Isomerization Reaction ◽  
Aliphatic Acids ◽  
Aqueous Acid

1-Aminobarbituric acid undergoes a facile isomerization in aqueous acid to 2-(5-oxo-4,5-dihydro-lH-l,2,4-triazol-3-yl)acetic acid which in turn can be decarboxylated to give 3-methyl-1H-1,2,4- triazol-5(4H)-one. The isomerization reaction is shown to be a general one, adaptable to the synthesis of oxotriazolyl aliphatic acids and their decarboxylated products. A reaction mechanism for the isomerization is proposed.

Theoretical study of the ketonization reaction mechanism of acetic acid over SiO2

2009 ◽  
Author(s):  
Mendel Fleisher ◽  
E. Lukevics ◽  
L. Leite ◽  
D. Jansone ◽  
K. Edolfa ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Theoretical Study

scholarly journals Synthesis of spiro[dihydropyridine-oxindoles] via three-component reaction of arylamine, isatin and cyclopentane-1,3-dione

2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Room Temperature ◽  
The Other ◽  
Other Hand ◽  
Three Component Reaction ◽  
High Yields

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.

scholarly journals Theoretical Study of the Isomerization Reaction Mechanism of Nitrile N-Oxide to Isocyanate under Basic Conditions

2019 ◽  
Vol 18 (5) ◽  
pp. 230-232
Author(s):  
Yuki ISHIYAMA ◽  
Yoshihiro HAYASHI ◽  
Toshikazu TAKATA ◽  
Susumu KAWAUCHI
Keyword(s):  
Reaction Mechanism ◽  
Theoretical Study ◽  
Isomerization Reaction

Reaction Mechanism of the Decomposition of Acetic Acid on Illuminated TiO2Powder Studied by Means ofin SituElectron Spin Resonance Measurements

Langmuir ◽  
1996 ◽  
Vol 12 (3) ◽  
pp. 736-738 ◽  
Author(s):  
Yoshio Nosaka ◽  
Katsuchika Koenuma ◽  
Kiminori Ushida ◽  
Akira Kira
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Spin Resonance

N-Methylamino Acids in Peptide Synthesis. III. Racemization during Deprotection by Saponification and Acidolysis

1973 ◽  
Vol 51 (15) ◽  
pp. 2555-2561 ◽  
Author(s):  
John R. McDermott ◽  
N. Leo Benoiton
Keyword(s):  
Acetic Acid ◽  
Sodium Hydroxide ◽  
Hydrogen Bromide ◽  
Aqueous Sodium Hydroxide ◽  
Acid Strength ◽  
Carboxyl Group ◽  
Aqueous Sodium ◽  
Aqueous Acid ◽  
Amino Acid Analyzer ◽  
Anhydrous Acetic Acid

The racemization of N-methylamino-acid derivatives in aqueous sodium hydroxide and hydrogen bromide in anhydrous acetic acid and other solvents has been investigated by determining the products of the reaction with an amino-acid analyzer after deprotection. Whereas MeIle-OMe, Z-MeIle, and the N-unmethylated derivatives were only slightly racemized ( <2%), Z-MeIle-OMe (18–24%), Z-Ala-MeLeu-OMe (22%), and Z-Ala-MeLeu-OBu′ (7%) were appreciably racemized by aqueous sodium hydroxide. It is suggested that these derivatives racemize because of the absence of an > N—H or carboxyl group whose ionization would suppress ionization of the neighboring α-C—H bond. Z-Melle and Z-Ala-MeLeu were substantially racemized (68% in 4 h and 34% in 1 h, respectively) by 5.6 N hydrogen bromide in acetic acid. The extent of racemization by acid varied with acid strength, polarity of solvent, and time. Incorporation of label into both isomers of Ala-MeLeu from a solution of the tritiated reagent established that ionization at the α-C—H bond had occurred. No racemization was caused by aqueous acid or by hydrogen chloride.

CO2 laser-induced decomposition of acetone, 2,3-butanedione and cyclobutanone sensitized by sulfur hexafluoride

1980 ◽  
Vol 45 (6) ◽  
pp. 1805-1811 ◽  
Author(s):  
Josef Pola ◽  
Josef Vítek ◽  
Milan Horák ◽  
Pavel Engst
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Partial Pressure ◽  
Decomposition Rate ◽  
Laser Power ◽  
Sulfur Hexafluoride ◽  
Buffer Gas ◽  
Sulphur Hexafluoride ◽  
Pyrolytic Products ◽  
Induced Decomposition

The CO2 cw laser powered homogeneous pyrolysis (LPHP) of acetone, 2,3-butanedione and cyclobutanone (all 1.3 - 4kPa) sensitized by sulphur hexafluoride (0.7-1.3kPa) was investigated. The decomposition course of the ketones is analogous to that occuring under conventional pyrolytic conditions. The decomposition rate and the product composition are affected by laser power, partial pressure of the sensitizer, and the buffer gas (helium) added. Besiedes the conventional pyrolytic products, the LPHP of acetone and 2,3-butanedione affords acetylene and that of cyclobutanone produces acetic acid. A possible reaction mechanism of the decompositions is discussed.

Study the reaction mechanism of catalytic reforming of acetic acid through the instantaneous gas production

2019 ◽  
Vol 44 (39) ◽  
pp. 21279-21289 ◽  
Author(s):  
Andong Zhang ◽  
Zhihe Li ◽  
Weiming Yi ◽  
Peng Fu ◽  
Lihong Wang ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Gas Production ◽  
Catalytic Reforming

The catalytic isomerization of allylbenzene in the presence of palladium(II) chloride

1966 ◽  
Vol 19 (5) ◽  
pp. 815 ◽  
Author(s):  
B Cruikshank ◽  
NR Davies
Keyword(s):  
Acetic Acid ◽  
Palladium Complex ◽  
Zero Order ◽  
Small Extent ◽  
Isomerization Reaction ◽  
Methyl Derivative ◽  
Initial Formation ◽  
First Order ◽  
Catalytic Isomerization ◽  
Cis Isomer

Allylbenzene has been shown to isomerize rapidly in the presence of palladmm(11) chloride in acetic acid, mainly to trans-β-methylstyrene but to a small extent to the cis isomer. The reaction is not simple. The initial formation of an olefin complex is succeeded by a further slow reaction involving the palladium complex before isomerization takes place. The isomerization reaction itself is zero order with respect to allylbenzene except nearing completion when it becomes first order in allylbenzene concentration. The reaction is first order with respect to catalyst. Rates have been measured by a technique involving N.M.R. spectrometry. Substitution in allylbenzene inhibits isomerization in the case of 2-bromoallylbenzene but not entirely in the case of the corresponding methyl derivative. The mechanism is discussed in the light of an intermediate hydrido complex.

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