Glyoxylic acid periodate oxidation

On the basis of experiments with myoinositol (50), it has been suggested that triose reductone should be oxidized by periodate to yield two molar equivalents of formic acid and one molar equivalent of carbon dioxide. However, it has been reported by two groups (1,29) that crystalline triose reductone is oxidized by two moles of periodic acid to give formic acid and glyoxylic acid, free iodine being liberated during the... 

Hesse and Mix (29) oxidized a relatively concentrated solution of triose reductone using limited amounts of free periodic acid. In these conditions, the iodic acid formed by the initial reduction of periodic acid could be further reduced and the reduction product could then, in turn, react with the remaining periodic acid and liberate iodine. Thus glyoxylic acid could be isolated from the oxidation mixture, as no periodate was available for its oxidation. 

Mesoxalic dialdehyde can be reasonably expected (16,28,50) to undergo normal glycol cleavage and give one mole of formic acid and one mole of glyoxylic acid in fact, when a second molar equivalent of periodate was added to the above solution, two molar equivalents of titratable acid were formed. If an excess of periodate is now added, two molar equivalents of titratable acid remain, but in addition, one molar equivalent of carbon dioxide can be expelled from the solution. Thus, in the overall reaction, one mole of triose reductone is oxidized by three moles of periodate to give two moles of formic acid and one mole of carbon dioxide ... 

The oxidation of aqueous ethanedial to glyoxylic acid is inclined to induction periods and then runaway, cessation and renewed runaway, as the nitric acid is progessively added. Probably this is the same problem as with formic acid, oxalic acid (above). 

Measurement of the acidity produced in the periodate oxidation of carbohydrates is confined mainly to the determination of formic acid. Only from unsubstituted ketoses is the formation of such acids as glyoxylic and glycolic to be expected in carbohydrate chemistry.274... 

In a critical study of the periodate oxidation of raffinose and related oligosaccharides, Courtois and Wickstrom showed78 that 1 mole of raffinose reduces 5 moles of periodate, with the formation of 2 moles of formic acid plus a hexaldehyde. Conversion of the aldehyde to the hexa-carboxylic acid, followed by hydrolysis, gave the expected amounts of glyoxylic acid, glyceric acid, hydroxypyruvic acid, and glycolaldehyde (by decarboxylation of hydroxypyruvic acid). 

The action of periodic acid on ketohexoses98 shows a rapid consumption of 4 atoms of oxygen, slowly approaching 5 atoms of oxygen per mole of sugar. In this oxidation two moles each of formaldehyde and formic acid are produced immediately and a third mole of formic acid as well as carbon dioxide are slowly formed by further oxidation of the preformed glyoxylic acid. 

Recently, Sprinson and Chargaff97 have inferred that periodate oxidation of L-sorbose gives rise to two esters of glycolaldehyde, namely the glyoxylic acid ester (XLII) and probably the glycolic acid ester (XLIII). 

Confirmatory evidence for streptosonic acid diamide existing as structure XXI was obtained by a study of the oxidation products of streptosonic acid monolactone (XXIII). When this compound was oxidized with two moles of periodic acid, two of the cleavage products were identified as glyoxylic acid (XXIV) and oxalic acid (XXV). The suggested course of the oxidation, on the basis of structure XXIII, is shown... 

A similar route has been suggested to account for the formation of glyoxylic acid (18, R = H) and methyl glyoxylate (18, R = Me) during the periodate oxidation of inositols and (9-methylinositols, respectively. Formation of these carboxy derivatives was depicted by sequences involving enolization to such reductones as 16, which are hydroxylated to 17 and then cleaved oxidatively. 

The above structure is confirmed by the results obtained by periodic acid oxidation 93), Sucrose consumes three moles of periodic acid, and one mole of formic acid is formed. (See earlier discussion in this chapter.) After bromine oxidation of the tetraaldehyde and subsequent hydrolysis, hydroxy-pyruvic, D-glyceric, and glyoxylic acids are obtained. (For a discussion of this method see p. 215.)... 

An improved method has been described for the preparation of glyoxylic acid esters by oxidative cleavage of the corresponding tartrates use of ethereal periodic acid necessitates no work-up procedure, obviating the problem of water solubility of the lower glyoxylates. j8-Keto-csters are dehy ated to the corresponding acetylenic esters by oxidation of the derived 5-pyrazolones with thallium(in) nitrate (Scheme 36). 

They proposed a number of mechanisms for oxidation of the intermediate product which is acetone dicarboxylic acid. In one route, acetone dicarboxylic acid is oxidized by periodic acid to give 2-hydroxy-3-ketoglutaric acid, HOOCCH(OH) COCH2COOH, which further can be oxidized to glyoxylic acid, HOOCCOH and finally to malonic acid HOOCCH2COOH. In the second path, acetone dicarboxylic acid is oxidized to y-lactone which in a series of consecutive reactions finally gives carbon dioxide, formic and oxalic acids. 

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