LITHIUM CHLORIDE CATALYZED DECARBOXYLATION OF OXALACETIC ACID IN ETHANOL

1964 ◽  
Vol 42 (12) ◽  
pp. 2806-2810 ◽  
Author(s):  
G. W. Kosicki ◽  
S. N. Lipovac ◽  
R. G. Annett
Keyword(s):  
Hydrogen Chloride ◽  
Lithium Chloride ◽  
Pyruvic Acid ◽  
Metal Salt ◽  
Enol Form ◽  
Absorption Peak ◽  
Oxalacetic Acid ◽  
Monovalent Metal

The monovalent metal salt lithium chloride promotes the decarboxylation of oxalacetic acid in ethanol. The absorption peak which appears at 230 mμ during the reaction is interpreted to be the enol form of pyruvic acid. Hydrogen chloride has a similar effect on the decarboxylation.

scholarly journals Pyranoanthocyanin Derived Pigments in Wine: Structure and Formation during Winemaking

2013 ◽  
Vol 2013 ◽  
pp. 1-15 ◽  
Author(s):  
Ana Marquez ◽  
María P. Serratosa ◽  
Julieta Merida
Keyword(s):  
Pyruvic Acid ◽  
Formation Process ◽  
Second Generation ◽  
Type A ◽  
Enol Form ◽  
Hydroxycinnamic Acids ◽  
The Other ◽  
Yeast Fermentation ◽  
Type B ◽  
Initial Compound

In recent years many studies have been carried out on new pigments derived from anthocyanins that appear in wine during processing and aging. This paper aims to summarize the latest research on these compounds, focusing on the structure and the formation process. The main pyranoanthocyanins are formed from the reaction between the anthocyanins and some metabolites released during the yeast fermentation: carboxypyranoanthocyanins or type A vitisins, formed upon the reaction between the enol form of the pyruvic acid and the anthocyanins; type B vitisins, formed by the cycloaddition of an acetaldehyde molecule on an anthocyanin; methylpyranoanthocyanins, resulted from the reaction between acetone and anthocyanins; pinotins resulted from the covalent reaction between the hydroxycinnamic acids and anthocyanins; and finally flavanyl-pyranoanthocyanins. On the other hand, the second generation of compounds has also been reviewed, where the initial compound is a pyranoanthocyanin. This family includes oxovitisins, vinylpyranoanthocyanins, pyranoanthocyanins linked through a butadienylidene bridge, and pyranoanthocyanin dimers.

Hydrogen chloride partial pressure of dilute hydrogen chloride-concentrated lithium chloride aqueous solutions

1971 ◽  
Vol 43 (2) ◽  
pp. 206-211 ◽  
Author(s):  
Elio. Scarano ◽  
Giovanni. Gay ◽  
Michele. Forina
Keyword(s):  
Aqueous Solutions ◽  
Partial Pressure ◽  
Hydrogen Chloride ◽  
Lithium Chloride

Dissociation constant of hydrochloric acid from partial vapor pressures over hydrogen chloride-lithium chloride solutions

1971 ◽  
Vol 43 (7) ◽  
pp. 969-970 ◽  
Author(s):  
Robert Anthony. Robinson ◽  
Roger G. Bates
Keyword(s):  
Hydrochloric Acid ◽  
Dissociation Constant ◽  
Hydrogen Chloride ◽  
Lithium Chloride ◽  
Vapor Pressures ◽  
Chloride Solutions

ISOTOPE RATE EFFECTS IN THE ENOLIZATION OF OXALACETIC ACID

1962 ◽  
Vol 40 (7) ◽  
pp. 1280-1284 ◽  
Author(s):  
George W. Kosicki
Keyword(s):  
Direct Evidence ◽  
Aqueous System ◽  
Enol Form ◽  
Rate Effect ◽  
Keto Form ◽  
Oxalacetic Acid ◽  
Rate Determining Step ◽  
Rate Effects ◽  
Acid Catalyzed ◽  
Catalyzed Reactions

Acid-catalyzed enolization of oxalacetic acid in H2O and D2O gives rise to a constant isotope rate effect [Formula: see text] of 2.4 over the pH (pD) range of 5.5 to 7.5. Base-catalyzed enolization of oxalacetic acid in H2O and D2O gives rise to a constant isotope rate effect [Formula: see text] of 4.5 over the pH (pD) range of 7.0 to 8.0. The percentage of enol form of oxalacetic acid was calculated to be 15.3% at pH 8.0, using the absorption of the enol form in ether at 255 mμ and the absorption of the keto form at pH 0.5 in an aqueous system. The spectrophotometric measurement of the isotope rate effect involved in the enolization of oxalacetic acid gives direct evidence for the rate-determining step in both the acid- and the base-catalyzed reactions without subsequent reactions.

Decomposition of Organic Acids During Processing and Storage

1976 ◽  
Vol 39 (7) ◽  
pp. 477-480 ◽  
Author(s):  
N. T. CHU ◽  
F. M. CLYDESDALE
Keyword(s):  
Acetic Acid ◽  
Organic Acids ◽  
Pyruvic Acid ◽  
Tissue Concentration ◽  
Process Time ◽  
Oxalacetic Acid ◽  
High Temperature Short Time ◽  
Aconitic Acid ◽  
Processing And Storage ◽  
Short Time

Solutions (0.1 N) of organic acids as well as tissue concentration levels were processed at several temperatures with varyious F0 values. Analyses were done using an automatic organic acid analyzer and paper chromatography. Pyrrolidone-carboxylic acid was produced from glutamic acid, fumaric from maleic acid, itaconic and trans-aconitic from cis-aconitic acid, malonic acid decomposed to acetic acid, and oxalacetic to pyruvic acid. At tissue concentration level oxalacetic acid decomposed completely at all process temperatures to pyruvic acid and to a lesser degree during storage without processing. Decomposition of other organic acids increased with increasing process time. The decompositon of malonic to acetic acid was the only reaction which was decreased significantly by use of a High-temperature Short-time process. However, the amount of decomposition of all acids, except oxalacetic, was low both after processing and during storage.

Efficient synthesis of some oxalacetic acid and pyruvic acid derivatives from the reactions of 2,3-furandiones with 2-phenylindole

2008 ◽  
Vol 49 (17) ◽  
pp. 2828-2831 ◽  
Author(s):  
Ahmet Şener ◽  
Nurettin Mengeş ◽  
Mehmet Akkurt ◽  
Selvi Karaca ◽  
Orhan Büyükgüngör
Keyword(s):  
Pyruvic Acid ◽  
Efficient Synthesis ◽  
Oxalacetic Acid

scholarly journals Metal Complexes in Acetic Acid. I. Kinetics and Mechanism of Reactions of Tetra-μ-acetato-dicopper(II) with Lithium Chloride and Hydrogen Chloride

1980 ◽  
Vol 53 (6) ◽  
pp. 1555-1559 ◽  
Author(s):  
Shigenobu Funahashi ◽  
Tetsuo Nishimoto ◽  
Pradyot Banerjee ◽  
Kiyoshi Sawada ◽  
Motoharu Tanaka
Keyword(s):  
Acetic Acid ◽  
Metal Complexes ◽  
Hydrogen Chloride ◽  
Lithium Chloride ◽  
Kinetics And Mechanism
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