Investigation of the kinetics of the synthesis of methylheptenone under conditions of homogeneous acid catalysis

1981 ◽  
Vol 15 (11) ◽  
pp. 798-801
Author(s):  
M. M. Avrutskii ◽  
M. A. Miropol'skaya ◽  
M. G. Romanyuk ◽  
I. B. Tikhova ◽  
N. I. Zakharova ◽  
...  
Keyword(s):  
Acid Catalysis ◽  
Homogeneous Acid ◽  
Kinetics Of

Kinetics and mechanism of cyclization of N-(2-methoxycarbonylphenyl)-N’-methylsulphonamide to 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide

1991 ◽  
Vol 56 (8) ◽  
pp. 1701-1710 ◽  
Author(s):  
Jaromír Kaválek ◽  
Vladimír Macháček ◽  
Miloš Sedlák ◽  
Vojeslav Štěrba
Keyword(s):  
Potassium Hydroxide ◽  
Acid Catalysis ◽  
Potassium Hydroxide Solution ◽  
Hydroxide Solution ◽  
General Base ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
Cyclization Kinetics ◽  
Rate Limiting ◽  
Kinetics Of

The cyclization kinetics of N-(2-methylcarbonylphenyl)-N’-methylsulfonamide (IIb) into 3-methyl-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide (Ib) has been studied in ethanolamine, morpholine, and butylamine buffers and in potassium hydroxide solution. The cyclization is subject to general base and general acid catalysis. The value of the Bronsted coefficient β is about 0.1, which indicates that splitting off of the proton from negatively charged tetrahedral intermediate represents the rate-limiting and thermodynamically favourable step. In the solutions of potassium hydroxide the cyclization of dianion of the starting ester IIb probably becomes the rate-limiting step.

Kinetics of the Acid Catalysis of the Hydration of Fumaric Acid to Malic Acid

1957 ◽  
Vol 61 (12) ◽  
pp. 1637-1640 ◽  
Author(s):  
Lee T. Rozelle ◽  
Robert A. Alberty
Keyword(s):  
Fumaric Acid ◽  
Malic Acid ◽  
Acid Catalysis ◽  
Kinetics Of

scholarly journals FATTY ACID ESTERIFICATION: EFFECTS OF UNSATURATION AND SYNTHESIS WITH THERMAL HEATING VIA ULTRASON AND MICROWAVES

2018 ◽  
Vol 15 (30) ◽  
pp. 447-462
Author(s):  
M. C. de M. SOUZA ◽  
L. DI SOUZA ◽  
V. P. da S. Caldeira ◽  
A. G. D. SANTOS ◽  
B. ADILSON
Keyword(s):  
Fatty Acids ◽  
Oleic Acid ◽  
Fatty Acid ◽  
Energy Demand ◽  
Fossil Fuels ◽  
Acid Catalysis ◽  
Thermal Heating ◽  
Ultrasonic Methods ◽  
Homogeneous Acid ◽  
Acid Esterification

With the increasing selective energy demand, fossil fuels are becoming scarce and environmentally incorrect, a viable alternative to this problem being the production of biodiesel. However, the esterification and transesterification reactions used are slow, expensive and ecologically incorrect because they produce polluting waste. Thus, it is necessary to develop techniques, reagents and equipment that make them fast, cheap and environmentally friendly. This work evaluated the performance of the thermal heating, microwave and ultrasonic methods in the esterification efficiency of oleic and stearic fatty acids via homogeneous acid catalysis. The efficiency of the reaction was certificated with the variables: time, yield and conversion and the biodiesel characterization were done with TG / DTG, FTIR and NMR. Conversions were determined by TG and 1H NMR and the yield by gravimetry. The results showed conversion with all methods with differences in the analyzed variables. The yields decrease in the microwave order (52%) conduction (33%) ultrasound (30%) for reactions with oleic acid and are practically the same (22, 22 and 20), independently of the stearic acid. Among the methods used, the most efficient is the microwave, because it has a higher yield in the case of oleic acid and reducing the reaction time.

scholarly journals Mechanism and theory of d-glucopyranose homogeneous acid catalysis in the aqueous solution phase

2019 ◽  
Vol 21 (32) ◽  
pp. 17993-18011 ◽  
Author(s):  
Manik Kumer Ghosh ◽  
Mícheál Séamus Howard ◽  
Karla Dussan ◽  
Stephen Dooley
Keyword(s):  
Aqueous Solution ◽  
Acid Hydrolysis ◽  
Acid Catalysis ◽  
Theoretical Study ◽  
Solution Phase ◽  
Homogeneous Acid ◽  
Hydrolysis Of

Theoretical study of the mechanism of acid hydrolysis of β-d-glucopyranose in the aqueous solution.

Reaction kinetics of 1,2-diaminobenzene with ethyl 2-oxopropanoate and 2,3-butanedione

1988 ◽  
Vol 53 (12) ◽  
pp. 3154-3163 ◽  
Author(s):  
Jiří Klicnar ◽  
Jaromír Mindl ◽  
Ivana Obořilová ◽  
Jaroslav Petříček ◽  
Vojeslav Štěrba
Keyword(s):  
Reaction Kinetics ◽  
Acid Catalysis ◽  
Reaction Pathway ◽  
Hydroxide Ion ◽  
Tetrahedral Intermediate ◽  
Rate Limiting Step ◽  
Limiting Step ◽  
General Acid ◽  
Rate Limiting ◽  
Kinetics Of

The reaction of 1,2-diaminobenzene with 2,3-butanedione is subject to general acid catalysis in acetate and phosphate buffers (pH 4-7). The rate-limiting step of formation of 2,3-dimethylquinoxaline consists in the protonation of dipolar tetrahedral intermediate. In the case of the reaction of 1,2-diaminobenzene with ethyl 2-oxopropanoate, the dehydration of carbinolamine gradually becomes rate-limiting with increasing pH in acetate buffers, whereas in phosphate buffers a new reaction pathway makes itself felt, viz. the formation of amide catalyzed by the basic buffer component and by hydroxide ion.

Kinetics of the hydrolysis of the dichromate ion. V. General acid catalysis

1969 ◽  
Vol 73 (12) ◽  
pp. 4391-4394 ◽  
Author(s):  
R. Baharad ◽  
Berta Perlmutter-Hayman ◽  
Michael A. Wolff
Keyword(s):  
Acid Catalysis ◽  
General Acid ◽  
Kinetics Of ◽  
Hydrolysis Of

Synthesis of terpineol from α-pinene by homogeneous acid catalysis

2005 ◽  
Vol 107-108 ◽  
pp. 310-314 ◽  
Author(s):  
M. Román-Aguirre ◽  
L. De la Torre-Sáenz ◽  
Wilber Antúnez Flores ◽  
A. Robau-Sánchez ◽  
A. Aguilar Elguézabal
Keyword(s):  
Acid Catalysis ◽  
Homogeneous Acid
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