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Carboxylic acids tartaric

Fig. 1 Absorption scan of a chromatogram with 10 pg ( ) per chromatogram zone of the carboxylic acids tartaric acid (1), malic acid (2), lactic acid (3), succinic acid (4), fumaric acid (5), stearic acid + front (6). Fig. 1 Absorption scan of a chromatogram with 10 pg ( ) per chromatogram zone of the carboxylic acids tartaric acid (1), malic acid (2), lactic acid (3), succinic acid (4), fumaric acid (5), stearic acid + front (6).
The carboxylic acids tartaric acid hRflS — 20), malic acid hRf 25 — 30), lactic acid hRf 45 — 50), succinic acid (hRf 60—65), fumaric acid (hRf 80) and stearic acid hRf 95 — 100) yielded orange-red zones on a violet background. [Pg.259]

Tartrates are salts of the diprotic carboxylic acid (+)-tartaric acid (Figure 3.33.1) (or L-tartaric acid). This tartaric acid is the natural occurring form, but the (-)-tartaric acid and the racemate are commercially available as well. The two acid groups have pKa values of 2.93 and 4.43, respectively. The tartaric acid is a crystalline solid, with a high water solubility. Their ammonium and potassium salt has a limited solubility, a fact that in the pharmacopoeia is used for the identification of potassium in 3.27. Potassium. The salts of the other alkali metals are soluble, but salts of most other inorganic cations are sparingly soluble. ... [Pg.82]

Similar polyacetal structures were prepared by BASF scientists from general dialdehydes and aliphatic hydroxycarboxylic acids derived from sugars [156, 157], shown in Scheme 15. Alternatively, carboxypolyacetals are available by the addition of polyhydroxy carboxylic acids, tartaric acid, for example, to divinyl ethers [158]. [Pg.509]

Take two test-tubes A and B in A place about 5 ml. of neutralised tartaric acid solution and in B place 5 ml. of distilled water. To each solution add 3-4 drops of ferric chloride solution. Place a piece of white paper under the tubes, look down their length and note that A is definitely yellow compared with the control tube B. This yellow colour is given by a-hydroxy-carboxylic-acids, lactic acid, tartaric acid, citric acid. [Pg.333]

Supplement (combined with Volume IV) III, 2nd 1929 195-449 Hydroxy-carboxylic acids Carbonic acid, 3. GlycoUic acid, 228. Lactic acid, 261. Tartaric acid, 481. Citric acid, 556. Urea, 42. Cyanamide, 74. Thiocyemic acid, 140. [Pg.1119]

Bromophenol blue (3.0...4.6) aliphatic carboxylic acids [225 — 228] malonic and lactic acids [229] palmitic and lactic acids [230] malonic, glycolic, malic, citric, tartaric, ketoglutaric, galacturonic and oxalic acids [196] dicarboxylic acids, succinic acid [231] indoleacetic acid, trichloroacetic acid [232] palmitic acid, palmityl- and stearyllactic acid [223] benzoic, sorbic and salicylic acid [234] metabolites of ascorbic acid [235] chloropropionic acid [236] oligogalacturonic acids [237] amino acids, hydrocarbons, mono-, di- and triglycerides [238] xylobiose, xylose, glucose and derivatives [239] sugar alcohols [91] toxaphene [240]... [Pg.45]

Enantiopure (R)- and (S)-nipecotic acid (Nip) derivatives 64 were obtained following classical resolution of ethyl nipecotate with either enantiomer of tartaric acid and successive recrystallization of the corresponding salts [153, 154, 156] or by resolution of racemic nipecotic acid with enantiomerically pure camphorsul-fonic acid [154]. N-Boc protected pyrrolidine-3-carboxylic acid (PCA) 65 for the synthesis of homo-ohgomers [155] was prepared by GeUman from trans-4-hydroxy-L-prohne according to a known procedure [157]. [Pg.49]

Carboxylic acids present no exceptional problems in reversed phase analysis, although detectability may be a limitation in the analysis of simple fatty acids. Wine acids, including succinic, acetic, citric, lactic, malic, and tartaric,... [Pg.161]

It should be emphasized that citric acid is not the only possible acid employed in Pechini-type syntheses. Other polybasic carboxylic hydroxy acids (malic, tartaric, hydroxyglutaric, etc.) and polybasic carboxylic acids (e.g., succinic) have been probed in Refs. [4, 13-16], As far as amino acids are concerned, glycine seems to remain the only representative [13, 14]. However, the choice of each particular organic acid has never been justified, and no comparative studies are performed in order to find possible dependencies of the process (ability to form a sol, a gel, or a resin, easiness of thermal decomposition of precursors, etc.) on the steric factors, specifically, on the number of hydroxy and carboxylic groups in the molecule of an acid, as well as on the length of its carbon skeleton. [Pg.503]

Figure 4.7 Anion exchange separation of carboxylic acids in red wine. Column, Shodex C811, 100 cm x 7.6 mm i.d. eluent, 3 mM perchloric acid flow rate, 0.9 ml min-1 temperature, 60 °C detection, reaction detection using chloro-phenol red at 430 nm. Peaks 1, citric acid 2, tartaric acid 3, malic acid 4, succinic acid 5, lactic acid 6, formic acid and 1, acetic acid. Figure 4.7 Anion exchange separation of carboxylic acids in red wine. Column, Shodex C811, 100 cm x 7.6 mm i.d. eluent, 3 mM perchloric acid flow rate, 0.9 ml min-1 temperature, 60 °C detection, reaction detection using chloro-phenol red at 430 nm. Peaks 1, citric acid 2, tartaric acid 3, malic acid 4, succinic acid 5, lactic acid 6, formic acid and 1, acetic acid.
Box recommends the addition of oxalic acid, tartaric acid or another di-carboxylic acid, to sulfuric acid for plating technetium either as a metal or oxide. On copper electrodes in 0.7 M oxalate and 0.45 M sulfuric acid, more than 99% of technetium metal is plated at 1.0-1.3 A/cm from a pertechnetate solution. However, from 0.4 M oxalate and 1.9 M sulfuric acid it is the oxide that is deposited. [Pg.130]

The initial medicinal chemistry route to the azabicyclo[3.3.0]octane-3-carboxylic acid produced the azabicyclo system in a diastereoselective but racemic manner, and required a classical resolution to achieve enantioenriched material (Teetz et al., 1984a, b 1988). Reaction of (R)-methyl 2-acetamido-3-chloropropanoate (43) and 1-cyclopentenylpyrrolidine (44) in DMF followed by an aqueous acidic work-up provided racemic keto ester 45 in 84% yield (Scheme 10.11). Cyclization of 45 in refluxing aqueous hydrochloric acid provided the bicyclic imine, which was immediately reduced under acidic hydrogenation conditions. The desired cis-endo product 46 was obtained upon recrystaUization. The acid was protected as the benzyl ester using thionyl chloride and benzyl alcohol, providing subunit 47 as the racemate. Resolution of 47 was accomplished by crystallization with benzyloxy-carbonyl-L-phenylalanine or L-dibenzoyl-tartaric acid. [Pg.152]

Ions released into the matrix as the cement sets may interact with the organic part of the matrix. Metal ions, such as Ca + and AP+, may be chelated by car-boxylate groups, either on the polymer or on the tartaric acid additive. These have been considered in reasonable detail in the literature [230]. What has received far less attention is the possibility that fluoride ions might interact with carboxylic acid groups, either to modify the setting reaction or to become relatively securely anchored within the set cement. This possibility was raised in a review published in 1998 [230], but has not been followed up subsequently. It is based on the well-established observation that fluoride ion will form extremely strong hydrogen bonds with carboxylic acids in aqueous solution. They are of the type ... [Pg.358]

In carboxylic acid solutions, the corrosion rate increases with acid concentration (acetic, lactic) however, in oxalic and tartaric acid solutions, the dissolution of metal is associated with the formation of passive lead salt layer [341]. [Pg.824]

Access to racemic thiazolidine-2-carboxylic acid (3-thiaproline, 12) is obtained by reacting cysteamine (49) with glyoxylic acid ester (Scheme 9), 165>182>1831 whilst the reaction of (R)-cysteine with glyoxylic acid 184 1851 leads to (2/ /S,5/ )-thiazolidine-2-carboxylic acid. 185 The diastereomers of thiazolidine-2-carboxylic add (12) are rapidly interconverting and therefore cannot be separated. 185 In the presence of (2R,3R)- and (2S,3S)-tartaric acid, reaction of cysteamine with glyoxylic acid leads to the enantiomerically pure (2/ )- and (2S)-thia-zolidine-2-carboxylic acid salts. 186 The acids undergo fast racemization in acetic acid. 186 ... [Pg.74]

Similar polyacetals were prepared by BASF scientists from CO-aldehydic aliphatic carboxylic acids (189,190) and by the addition of poly(hydroxycarboxylic acid)s such as tartaric acid to divinyl ethers (191) as biodegradable detergent polymers. [Pg.482]


See other pages where Carboxylic acids tartaric is mentioned: [Pg.331]    [Pg.481]    [Pg.1045]    [Pg.72]    [Pg.103]    [Pg.580]    [Pg.464]    [Pg.5]    [Pg.237]    [Pg.156]    [Pg.332]    [Pg.396]    [Pg.276]    [Pg.434]    [Pg.31]    [Pg.412]    [Pg.1045]    [Pg.129]    [Pg.117]    [Pg.481]   
See also in sourсe #XX -- [ Pg.381 ]




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