Tartaric acid, formula

Ordinary (that is, dextrorotatory) tartaric acid (XX) corresponds to XXI and not to XXII, as is often stated erroneously in textbooks. Formula XXII applies to the enantiomorph of natural tartaric acid. Formulas XXI and XXIII are drawn in conformity with Fischer s first convention but formula XXII does not follow it. 

Racemic and Mesotartaric Acids.—These two acids represent two inactive types of compounds containing a< yminct7 ic carbon atoms (see above). Apart from certain well-marked differences in physical properties they also differ in one important feature racemic acid can be lesoh-ed into its optical enantiomorphs, whereas mesotartaric acid cannot. The latter belongs to what is termed the inactive indivisible type. If we examine the structuial formula of tartaric acid it will l>e seen that it possesses two asyimnetric carbon atoms, denoted in the formula by thick type. 

As the story goes, a wine production batch gone bad provided fairly large amounts of a new organic compound, the study of which was deemed of practical importance for the French wine industry. The new material had the same molecular formula as tartaric acid, which to some experts of the time meant it had to be the same as tartaric acid. Solutions of salts of the new material, however, did not rotate the plane of polarization of plane-polarized light, as solutions of salts of tartaric acid were known to do. The new material was named para tartaric acid, or racemic acid (the name racemic acid being derived from the Latin racemus bunch of grapes). 

The internal arrangement is knovm only in the case of ordi nary and inactive tartaric acids, which are both represented by the above formula. 

It now became clear that the (-H-tartaric acid produced by oxidation of n-saccharic (n-glucaric) acid is formed from its first four carbon atoms, and that racemic tartaric acid (31 + 32) is produced in the same manner, from mucic (galactaric) acid (19). The choice of formula (31) for (+)-... 

Thus, in cases where four different atoms or groups are attached to the same atom, it is possible to have two arrangements in space that cannot be made to coincide geometrically. This situation can be demonstrated by use of a special type of formula, shown in Fig. 2 for the two forms of the compound fluoroehlorobromomethane. This existence of two forms due to a difference in orientation in space is called stereoisomerism, and is discussed in the entry on Isomerism. It also follows that for compounds containing more than one atom bonded to four unlike groups, the number of different forms increases rapidly, as is shown by the three possible forms of tartaric acid, HOOC-CH-OH-CHOH-COOH. as portrayed by the three formulas shown in Fig. 3. 

CITRIC ACID. [CAS 77-92-9J. C.tH.,(OH)(COOH),. formula weight 192.12. white crystalline solid, mp 153. decomposes at higher temperatures, sp gr 1.542. Citric acid is soluble In H.O or alcohol and slightly soluble in ether. The compound is a trihasic acid, forming mono-, di-, and Iri- scries of salts and esters. Citric acid may be obtained (I) from some natural products, e.g., the free acid in the juice of citrus and acidic fruits, often in conjunction with malic or tartaric acid the juice of unripe lemons... 

The projection formulas of the four forms of tartaric acids are shown below. Note that the arrows indicate the direction of rotation of light by the asymmetric carbon atoms. 

Proceeding as we did for threonine, we can write four projection formulas for tartaric acid, 2,3-dihydroxybutanedioic acid, as shown by 23-26 ... 

The condition that makes possible the existence of meso compounds is an appropriate degree of molecular symmetry. There are several kinds of such molecular symmetry. In the case of projection formulas 25 (or 26) there is a plane of symmetry, which means that a plane can be placed through the molecule such that one half of the molecule is a mirror image of the other half The mirror plane for meso-tartaric acid can be seen easily from its projection formulas 25b and 26b. These two formulas are superimposable if one is rotated 180° in the plane of the paper. 

The Newman representation 25a or 26a of meso-tartaric acid does not have a mirror plane. Why is it different from the Fischer projections in this respect The reason is that the projection formulas represent a particular eclipsed conformation 27 of tartaric acid that does have a mirror plane ... 

Figure 1. Zig-zag formula of (R,R)-tartaric acid and its derivatives. X = NH2 for the diamide and X =N(CH3)2 for theN,N,N ,N -tetramethyldiamide.

Herbs mixture formula and type of vermouth Color (at 420 nm) Total acidity tartaric acid / pH 100 mL Volatile acidity (g. AA/100 mL) Alcohol (%, v/v) Total aldehyde (ppm) Total phenols (%) Organoleptic scores (out of 20)... 

To 5 cc. of IN CuSCh add 10 cc. of a molal solution of tartaric acid then add sodium hydroxide solution, as in (1), and compare the results with those in (1) and (2), but do not attempt to ascribe a definite formula to the complex compound formed. 

There are two chirality centers, so the formula predicts that there are four stereoisomers. However, because the chirality centers are identical, we expect that there are actually fewer than four stereoisomers. In fact, the analysis is identical to the one we just did for tartaric acid. There are three stereoisomers a d,l-pair of enantiomers and a meso-diastereomer. 

Its empirical formula is C2H3O3. If 1.00 mol of tartaric acid contains 3.61 x 1024 oxygen atoms, what is the molecular formula of tartaric acid ... 

Assay Mix 50.0 mL of sample with 500 mg of tartaric acid, shake for 5 min, and filter. Dry the filtered oil over anhydrous sodium sulfate, and then pipet 10.0 mL of the clear, treated oil into a 150-mL cassia flask. Add 75 mL of a 30% solution of sodium bisulfite, stopper the flask, and shake until a semisolid to solid sodium bisulfite addition product has formed. Allow the mixture to stand at room temperature for 5 min, then loosen the stopper, and immerse the flask in a water bath heated to between 85° and 90°. Maintain the water bath at this temperature, shaking the flask occasionally, until the addition product dissolves, and then continue heating and intermittently shaking for another 30 min. When the liquids have separated completely, add enough 30% sodium bisulfite solution to raise the lower level of the oily layer within the graduated portion of the flask s neck. Calculate the percentage, by volume, of the citral by the formula... 

The colour is due to the formation of a condensation product of resorcinol, C6H4(OH)2, and glycollic aldehyde, CH2OH.CHO, the latter arising from the action of the sulphuric acid upon the tartaric acid. The formula of the condensation product is CH2OH.CH[C6H3(OH)2]2. 

The results presented here suggest that a rich complex chemistry of pentacoordinate silicon with ligands derived from a-hydroxycarboxylic acids (including tartaric acid), hydroximic acids, and oxalic acid may be developed. As most of these ligands derive from natural products and as some of these X Si-silicon(IV) complexes were shown to exist in aqueous solution, compounds of this formula type are of particular interest it has been speculated in the literature [16] that silicon transport in biological systems might be based on higher coordinate Si species, and complexes such as the title compounds could be of interest as model systems in this respect. 

So far the most promising chiral Diels-Alder catalyst has been obtained in situ by treatment of monoacylated tartaric acid (470) with BHs-THF (1 mol equiv.)." The resulting non-isolated acyloxyborane was assumed to feature a five-membeied ring derived from the a-hydroxy acid moiety of (470) with die boron atom bound to the carboxylate and (Za-positioned oxygen atoms cf. formula 471) (Scheme 111, Table 32). 

By combining molecule to molecule, right-handed tartaric acid and left-handed tartaric acid form a polymery racemic acid. This acid, whose stereochemical formula is then superposable upon its image in a mirror, gives holoedric crystals gifted with the same property by dissolving it, one obtains a liquid devoid of rotary power. 

Fischer did not state his first convention in a fully generalized form instead, he indicated the manner in which he proposed to write the formulas for the three tartaric acids and he then wrote the formulas for the substances of the hexose and pentose series in an analogous way. The following is a free translation of his statement. 

Fischer then shows that when the arrangements for the enantio-morphous forms of saccharic acid that are specified by his use in his first article of Van t Hoff s -f and — signs (number 5 = 11 and 9 = 15 of Table I) are given to models, and these are projected as in the case of the tartaric acids, the formulas XII and XIII result. The present author has added the diagrams XI (= XII) and XIV (= XIII) in which the dotted straight line indicates those edges of the tetrahedra that lie in the plane of the paper this line is dotted to indicate that these edges are not... 

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