Kinetics of the reaction of ethanol and lauric acid catalyzed by deep eutectic solvent based on benzyltrimethylammonium chloride

Kinetics of formation of 2-imino-4-thiazolidone from S-ethoxycarbonylmethylisothiouronium chloride has been studied in aqueous buffers and dilute hydrochloric acid. The reaction is subject to general base catalysis, the β value being 0.65. Its rate limiting step consists in acid-catalyzed splitting off of ethoxide ion from dipolar tetrahedral intermediate. At pH < 2 formation of this intermediate becomes rate-limiting; rate constant of its formation is 2 . 104 s-1.

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Cyclization and acid-catalyzed hydrolysis of O-benzoylbenzamidoximes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19862786 ◽

1986 ◽

Vol 51 (12) ◽

pp. 2786-2797

Author(s):

František Grambal ◽

Jan Lasovský

Keyword(s):

Reaction Rate ◽

Kinetic Isotope ◽

Acid Base Equilibrium ◽

Mineral Acids ◽

Kinetics Of Formation ◽

Acid Catalyzed ◽

Ph Scale ◽

Kinetics Of ◽

Hydrolysis Of ◽

Derivatives Of

Kinetics of formation of 1,2,4-oxadiazoles from 24 substitution derivatives of O-benzoylbenzamidoxime have been studied in sulphuric acid and aqueous ethanol media. It has been found that this medium requires introduction of the Hammett H0 function instead of the pH scale beginning as low as from 0.1% solutions of mineral acids. Effects of the acid concentration, ionic strength, and temperature on the reaction rate and on the kinetic isotope effect have been followed. From these dependences and from polar effects of substituents it was concluded that along with the cyclization to 1,2,4-oxadiazoles there proceeds hydrolysis to benzamidoxime and benzoic acid. The reaction is thermodynamically controlled by the acid-base equilibrium of the O-benzylated benzamidoximes.

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Comparison of Corn Stover Pretreatments with Lewis Acid Catalyzed Choline Chloride, Glycerol and Choline Chloride-Glycerol Deep Eutectic Solvent

Polymers ◽

10.3390/polym13071170 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1170

Author(s):

Yuan Zhu ◽

Benkun Qi ◽

Xinquan Liang ◽

Jianquan Luo ◽

Yinhua Wan

Keyword(s):

Corn Stover ◽

Lewis Acid ◽

Choline Chloride ◽

Deep Eutectic Solvent ◽

Enzymatic Saccharification ◽

Glycerol Solution ◽

Cellulose Conversion ◽

Biomass Processing ◽

Acid Catalyzed ◽

Highly Correlated

Herein, corn stover (CS) was pretreated by less corrosive lewis acid FeCl3 acidified solutions of neat and aqueous deep eutectic solvent (DES), aqueous ChCl and glycerol at 120 °C for 4 h with single FeCl3 pretreatment as control. It was unexpected that acidified solutions of both ChCl and glycerol were found to be more efficient at removing lignin and xylan, leading to higher enzymatic digestibility of pretreated CS than acidified DES. Comparatively, acidified ChCl solution exhibited better pretreatment performance than acidified glycerol solution. In addition, 20 wt% water in DES dramatically reduced the capability of DES for delignification and xylan removal and subsequent enzymatic cellulose saccharification of pretreated CS. Correlation analysis showed that enzymatic saccharification of pretreated CS was highly correlated to delignification and cellulose crystallinity, but lowly correlated to xylan removal. Recyclability experiments of different acidified pretreatment solutions showed progressive decrease in the pretreatment performance with increasing recycling runs. After four cycles, the smallest decrease in enzymatic cellulose conversion (22.07%) was observed from acidified neat DES pretreatment, while the largest decrease (43.80%) was from acidified ChCl pretreatment. Those findings would provide useful information for biomass processing with ChCl, glycerol and ChCl-glycerol DES.

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Kinetic modelling of reactions for the synthesis of 2-methyl-5-ethyl pyridine

Reaction Chemistry & Engineering ◽

10.1039/d1re00085c ◽

2021 ◽

Author(s):

Emanuele Moioli ◽

Leo Schmid ◽

Peter Wasserscheid ◽

Hannsjoerg Freund

Keyword(s):

Kinetic Modelling ◽

Acid Catalyst ◽

Acid Catalyzed ◽

Catalyzed Reactions ◽

Kinetics Of

The kinetics of the acid catalyzed reactions of acetaldehyde ammonia trimer (AAT) and paraldehyde (para) to 2-methyl-5-ethyl pyridine (MEP) in the presence of an acid catalyst were investigated systematically. A...

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Meso tetrakis ortho-, meta-, and para-N-alkylpyridiniopor-phyrins: kinetics of copper(II) and zinc(II) incorporation and zinc porphyrin demetalation

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424603000197 ◽

2003 ◽

Vol 07 (03) ◽

pp. 139-146 ◽

Cited By ~ 6

Author(s):

Peter Hambright ◽

Ines Batinić-Haberle ◽

Ivan Spasojević

Keyword(s):

Aqueous Solution ◽

Ionic Strength ◽

Effective Charge ◽

Methyl Ethyl ◽

Ionic Strength Dependence ◽

Zinc Porphyrin ◽

Cationic Porphyrin ◽

Strength Dependence ◽

Acid Catalyzed ◽

Kinetics Of

The relative reactivities of the tetrakis( N -alkylpyridinium- X - yl )-porphyrins where X = 4 (alkyl = methyl, ethyl, n -propyl) , X = 3 (methyl) , and X = 2 (methyl, ethyl, n -propyl, n -butyl, n -hexyl, n -octyl) were studied in aqueous solution. From the ionic strength dependence of the metalation rate constants, the effective charge of a particular cationic porphyrin was usually larger when copper(II) rather than zinc(II) was the reactant. The kinetics of ZnOH + incorporation and the acid catalyzed removal of zinc from the porphyrins in 1.0 M HCl were also studied. In general, the more basic 4- (para-) and 3- (meta-) isomers were the most reactive, followed by the less basic 2- (ortho-) methyl to n -butyl derivatives, with the lipophilic ortho n -hexyl and n -octyl porphyrins the least reactive.

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Kinetics of the acid-catalyzed isomerization of phenylbutenes in glacial acetic acid

Journal of the American Chemical Society ◽

10.1021/ja00759a034 ◽

1972 ◽

Vol 94 (4) ◽

pp. 1247-1249 ◽

Cited By ~ 4

Author(s):

R. S. Schwartz ◽

H. Yokokawa ◽

E. W. Graham

Keyword(s):

Acetic Acid ◽

Glacial Acetic Acid ◽

Acid Catalyzed ◽

Kinetics Of

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High field 1H NMR Studies of Sol-Gel Kinetics

MRS Proceedings ◽

10.1557/proc-73-157 ◽

1986 ◽

Vol 73 ◽

Cited By ~ 7

Author(s):

Bruce D. Kay ◽

Roger A. Assink

Keyword(s):

Equilibrium Distribution ◽

Sol Gel ◽

Nmr Studies ◽

H Nmr ◽

Rate Limiting Step ◽

Rate Of Hydrolysis ◽

Acid Catalyzed ◽

Product Species ◽

Rate Limiting ◽

Kinetics Of

ABSTRACTHigh resolution 1H NMR spectroscopy at high magnetic fields is employed to study the reaction kinetics of the Si(OCH3)4:CH3OH:H2O sol-gel system. Both the overall extent of reaction as a function of time and the equilibrium distribution of species are measured. In acid catalyzed solution, condensation is the rate limiting step while in base catalyzed solution, hydrolysis becomes rate limiting. A kinetic model in which the rate of hydrolysis is assumed to be independent of the adjacent functional groups is presented. This model correctly predicts the distribution of product species during the initial stages of the sol-gel reaction.

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