Tartronic acid

Tartronic Acid HOOC—CH(OH) — COOH Mono-hydroxy Malonic Acid 

S30ithesis from Malonic Acid.—Tartronic Acid is obtained from malonic acid directly through mono-chlor malonic acid, 

Mono-hydrozy malonic acid (Tartronic acid) 

From Glycerol.—This synthesis shows tartronic acid to have the constitution given, i.e., mono-hydroxy malonic acid. It may also be obtained from glycerol by oxidation. In this reaction the two primary alcohol groups in glycerol are both oxidized to carboxyl while the secondary alcohol group remains unchanged. 

Mesoxalic Acid HOOC—C(OH)2—COOH Di— hydroxy Malonic Acid 

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Rea.ctlons, When free (R-R, R -tartaric acid (4) is heated above its melting point, amorphous anhydrides are formed which, on boiling with water, regenerate the acid. Further heating causes simultaneous formation of pymvic acid, CH COCOOH pyrotartaric acid, HOOCCH2CH(CH2)COOH and, finally, a black, charred residue. In the presence of a ferrous salt and hydrogen peroxide, dihydroxymaleic acid [526-84-1] (7) is formed. Nitrating the acid yields a dinitro ester which, on hydrolysis, is converted to dihydroxytartaric acid [617 8-1] (8), which upon further oxidation yields tartronic acid [80-69-3] (9). 

The reduced catalyst deactivation compared to the analogous oxidations of glycerol and tartronic acid was attributed to the use of the calcium salt rather than the free acid. A recent publication describes a similar observation for the oxidation of sodium gluconate [15]. Sodium ions were assumed to counter catalyst deactivation by neutralizing the acid species responsible. 

Tartronic acid was oxidised to mesoxalic acid on 6%Pt2%Bi/C, prepared by exchange/redox, under acidic conditions (reaction f, Scheme 1) (29% yield at 53% conversion, pH=1.5). Figure 10 shows that the conversion rate of tartronic acid is high at first but decreases as the reaction proceeds, probably because the formed mesoxalic acid is more strongly adsorbed on the surface than tartronic acid. The initial high selectivity tapers off due to over-oxidation. 

Figure 10. Product composition for the oxidation of tartronic acid, obtained at pH=1.5 on 6%Pt2%Bi/C, as a function of time.

The reaction described is of considerable general utility for the preparation of benzoyloxy derivatives of /8-carbonyl compounds. Thus 0-benzoyl tartronates have been prepared, from which routes to diethyl tartronates and tartronic acids have been developed. Ethyl benzoyloxy cyanoacetates have similarly been prepared and are of potential interest in connection with the chemistry of amino acid precursors. Similarly the benzoyloxy... 

Onl two acids belonging to this series are known, viz. tartronic acid and. malic acid. Like lactic acid, thejr both contain an atom of fwnhom Uo hydroxyl —... 

Tartronic acid 0.0608 d, Lr-jS-Hydroxy butyric acid No effect... 

The Au-catalyzed glycerol oxidation was influenced by the kind of support, the size of Au particles and the reaction conditions such as concentration of glycerol, p02 and molar ratio of NaOH to glycerol. As metal oxide supports showed inferior selectivity to glyceric acid compared to carbons, due to successive oxidation and C—C bond cleavage to form di-adds such as tartronic acid and glycolic acid, research has focused on Au NPs supported on carbon, as in the case of ethylene glycol oxidation [182]. Indeed, the catalytic activity was influenced by the kind of carbon support in terms of porous texture [183]. 

N1 - TARTRONIC ACID, DIETHYL ESTEP, eompd. with N-( (BENZYLOXY)CARBONYDGLYCINE... 

In the a approach by Mombarg et a/.,[59] oxidation of disaccharides, such as trehalose and sucrose (25 mmol), was performed in 25 ml of water at 70 °C, with 100 mg of Ti-MCM-41 (7.2 pmol of Ti) and 25 g of 35 wt% H2O2, at pH = 4. After 20 h of reaction, a deep oxidation is observed leading to C1-C4 mono- and dicarboxylic acids, formic acid, glycolic acid, tartronic acid and tartaric acid. The absence of selectivity is then a major drawback compared with other oxidation processes, but another drawback was identified with Ti leaching from the molecular sieve framework. 

Figure 2.2.12 Reaction network of glycerol oxidation (GLY, glycerol DHA, dihydroxyace-tone GLA, glyceric aldehyde GLS, glyceric acid HBT, hydroxypyruvic acid MOS, mesoxalic acid TS, tartronic acid GOX, glyoxal GOS, glycolic acid GYS, glyoxylic acid OS, oxalic acid).

Piperonylic acid 1,3-Benzodioxole-5-carboxylic acid Tartronic acid Propanedioic acid, hydroxy-... 

By the introduction of one more hydroxyl group into malic acid we obtain a di-hydroxy succinic acid which, as a di-hydroxy compound, is analogous to mesoxalic acid and bears the same relation to succinic acid and to malic acid that mesoxalic acid bears to malonic acid and to tartronic acid. The acid of this constitution is the commonly occurring substance tartaric acid.. That tartaric acid contains two carboxyl groups and at the same time two alcohol hydroxyl groups and that it is in fact di-hydroxy succinic acid is proven by several syntheses and reactions. 

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