Mechanisms of Acid Catalysis. The Kinetics and Mechanisms of the Acid-catalyzed Reactions of Ethyl Diazoacetate with Ethanol and Acetic Acid1

1952 ◽  
Vol 74 (14) ◽  
pp. 3679-3683 ◽  
Author(s):  
John D. Roberts ◽  
Clare M. Regan ◽  
Inka Allen
Keyword(s):  
Acid Catalysis ◽  
Ethyl Diazoacetate ◽  
Acid Catalyzed ◽  
Catalyzed Reactions

Synthetic Scope of Brønsted Acid-Catalyzed Reactions of Carbonyl Compounds and Ethyl Diazoacetate

2021 ◽  
Author(s):  
Mizzanoor Rahaman ◽  
M. Shahnawaz Ali ◽  
Khorshada Jahan ◽  
Damon Hinz ◽  
Jawad Bin Belayet ◽  
...  
Keyword(s):  
Carbonyl Compounds ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Ethyl Diazoacetate ◽  
Brönsted Acid ◽  
Acid Catalyzed ◽  
Catalyzed Reactions

Kinetics and mechanism of hydrolysis of 3-diazobenzofuran-2-one and its hydrolysis product (3-hydroxybenzofuran-2-one)

2002 ◽  
Vol 80 (1) ◽  
pp. 82-88
Author(s):  
Y Chiang ◽  
A J Kresge ◽  
Q Meng
Keyword(s):  
Acid Catalysis ◽  
Hydrolysis Product ◽  
Diazo Compound ◽  
Acidity Function ◽  
Hydroxide Ion ◽  
Mechanism Of Hydrolysis ◽  
Acid Catalyzed ◽  
Catalyzed Reactions ◽  
Rate Profile ◽  
Hydrolysis Of

Rates of acid-catalyzed hydrolysis of 3-diazobenzofuran-2-one, measured in concentrated aqueous perchloric acid and hydrochloric acid solutions, were found to correlate well with the Cox–Yates Xo excess acidity function, giving kH+ = 1.66 × 10–4 M–1 s–1, m‡ = 0.86 and kH+ /kD+ = 2.04. The normal direction (kH/kD > 1) of this isotope effect indicates that hydrolysis occurs by rate-determining protonation of the substrate on its diazo-carbon atom. It was found previously that the next higher homolog of the present substrate, 4-diazoisochroman-3-one, also undergoes hydrolysis by this reaction mechanism but with a rate constant 15 times greater than that for the present substrate; this difference in reactivity can be understood in terms of the various resonance forms that contribute to the structures of these substrates. The product of the present hydrolysis reaction is 3-hydroxybenzofuran-2-one, which itself quickly undergoes subsequent acid-catalyzed hydrolysis to 2-hydroxymandelic acid. The acidity dependence of this subsequent hydrolysis is much shallower than that of the diazo compound precursor, and rates of reaction correlate as well with [H+] as with Xo. This is due in part to incursion of a nonproductive protonation on the hydroxy group of 3-hydroxy benzo furan-2-one that impedes hydrolysis and produces saturation of acid catalysis. Rates of hydrolysis of the hydroxy compound were also measured in dilute HClO4 and NaOH solutions as well as in CH3CO2H, H2PO4–, (CH2OH)3CNH3+, and NH4+ buffers, and the rate profile constructed from these data showed the presence of uncatalyzed and hydroxide ion-catalyzed reactions. This hydroxide-ion catalysis became saturated at [NaOH] [Formula: see text] 0.05 M, implying occurrence of yet another nonproductive substrate ionization. Key words: diazo compound hydrolysis, lactone hydrolysis, Cox–Yates excess acidity, acid catalysis, alcohol protonation.

Acid-Catalyzed Reactions of Aromatic Aldehydes with Ethyl Diazoacetate:  An Investigation on the Synthesis of 3-Hydroxy-2-arylacrylic Acid Ethyl Esters

2004 ◽  
Vol 69 (22) ◽  
pp. 7599-7608 ◽  
Author(s):  
Matthew E. Dudley ◽  
Md. Monzur Morshed ◽  
Courtney L. Brennan ◽  
M. Shahidul Islam ◽  
M. Syarhabil Ahmad ◽  
...  
Keyword(s):  
Aromatic Aldehydes ◽  
Ethyl Esters ◽  
Ethyl Diazoacetate ◽  
Acid Catalyzed ◽  
Catalyzed Reactions

scholarly journals Sulfonic Acid-Functionalized Inorganic Materials as Efficient Catalysts in Various Applications: A Minireview

Catalysts ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1143
Author(s):  
Maria Luisa Testa ◽  
Valeria La Parola
Keyword(s):  
Acid Catalysis ◽  
Solid Acid ◽  
Catalyst Particle ◽  
Mineral Acid ◽  
Magnetic Core ◽  
Inorganic Materials ◽  
Green Solvents ◽  
Acid Catalyzed ◽  
Catalyzed Reactions ◽  
Synthetic Approaches

Acid catalysis is widely used in the chemical industry, and nowadays many efforts are being focused on replacing the more common homogeneous catalysts with heterogeneous ones in order to make greener the industrial processes. In this perspective, sulfonic solid acid materials represent a valid alternative to the homogenous mineral acid in several acid catalyzed reactions. In this minireview, an overview of the recent advances on the preparation, stability and application of these materials is reported. Special attention is addressed to the sustainability of the considered processes, starting from the catalyst’s preparation, the use of green solvents and reducing the possible reaction steps. Ways to tackle the main drawback represented by easy leaching of acid groups are described. For an easy catalyst recovery, the use of a magnetic core in a catalyst particle, with the related synthetic approaches, is also illustrated. Finally, a section is dedicated to the principal characterization techniques to identify the structural properties of the catalysts.

Acid-Catalyzed Reactions of Aromatic Aldehydes with Ethyl Diazoacetate: An Investigation on the Synthesis of 3-Hydroxy-2-arylacrylic Acid Ethyl Esters.

ChemInform ◽  
2005 ◽  
Vol 36 (11) ◽  
Author(s):  
Matthew E. Dudley ◽  
Md. Monzur Morshed ◽  
Courtney L. Brennan ◽  
M. Shahidul Islam ◽  
M. Syarhabil Ahmad ◽  
...  
Keyword(s):  
Aromatic Aldehydes ◽  
Ethyl Esters ◽  
Ethyl Diazoacetate ◽  
Acid Catalyzed ◽  
Catalyzed Reactions
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