Glyceric Aldehyde Acetal

Submitted by E. J. Witzemann, Wm. Lloyd Evans, Henry Hass, and 

The oxidation is very sensitive to changes in temperature. The best results are obtained at 50 a slight variation causes a marked decrease in the yield. 

If the mixture does not set to a gel, the yield is likely to be poor. This is usually due to poor temperature control. 

Sometimes two layers appear at first, but these disappear when the potassium carbonate is added. 

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Glutaric anhydride, 13, r3 /-Glyceric aldehyde, 11, 50 14, 86 dl-GLYCERIC ALDEHYDE ACETAL, 11, 50, 52... 

A mixture of 50 g. (0.3 mole) of dZ-glyceric aldehyde acetal (p. 52) and 500 cc. of 0.1 N sulfuric acid is allowed to stand for one week at about 20 0 (Note 1). The mixture is then treated with 30 cc. of glacial acetic acid and neutralized carefully with barium hydroxide solution (Note 2). The mixture is stirred with 5 g. of decolorizing carbon and filtered. The filtrate is evaporated at 10 mm. pressure (Note 3). When no more water can be removed, the residue is treated with an equal volume of absolute alcohol to hasten crystallization. The crystals are collected on a filter and dried in a vacuum desiccator over soda-lime and calcium chloride. The yield of product melting at 137-1390 is 22 g. (80 per cent of the theoretical amount) (Note 4). 

Glutaric anhydride, 13, 13 (ZZ-GLyCERIC ALDEHYDE, 11, SO 14, 86 (ZZ-Glyceric aldehyde ACETAL, 11, SO,... 

Glutamic acid, 10, in Glutaric AdD, 10, S8 (W-Glyceric aldehyde, 11, SO d/-GLYCERIC aldehyde ACETAL, 11, JO) S2... 

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