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Chemistry. — Mr. G. VAN DER SLEEN: “On a@-hydroxybutenoic acid 
(vinylglycollic acid) and its decompositions”. (Communicated 
by Prof. Lopry DE BRUYN). 
The investigation of vinylglycollic acid CH, : CH . CH (OHM) COOH, 
commenced in 1885 by Losry DE Bruyn!) has been again taken 
up?) in 1898; the various preparations were then obtained in large 
quantities. 600 grams of acroldehyde (acrolein) could be easily prepa- 
red in one day and converted by addition of HCN into the nitrile 
of «-hydroxybutenoic acid CH,: CH .CH (OH) CN. 
This substance, when pure, forms a colourless liquid b. p. (93—94° at 
16—17 mm.), and when freshly distilled it is free from HCN. It 
does not solidify at a temperature of — 70° to — 80° and is soluble 
in water in any proportion. By heating with acetic anhydride it was 
converted into the acetate. 
Both the nitrile and its acetate are converted by very careful treatment 
with fuming hydrochloric acid into the amide CH, : CH. CH(OH) CO N Ho, 
which melts at 80.8°. This pure amide has served as the starting point 
for all further experiments. It may be converted into e-hydroxybu- 
tenoie acid by different means, such as by boiling with normal sul- 
phurie acid or strong aqueous sodiumhydroxide. This acid was also 
obtained in fairly large quantities as a bye-product in the preparation 
of the said amide and purified by distillation in vacuum (125°—130° 
and 12—13 mm.) although not without partial decomposition into 
laetone-like substances. 
The acid crystallises in the form of needles which, however, cannot 
be obtained perfectly anhydrous by distillation ; it is exceedingly 
hygroscopic and but sparingly soluble in the ordinary organic solvents. 
The ester of a-hydroxybutenoie acid was obtained by treating the 
alcoholic solution of the nitrile with HCI: b.p. 173° (at 756.5 mm.). 
This ester is isomeric with that of aceto-acetic acid but gives no 
reaction with Fe Cls. 
Although the nitrile and the acetate absorb bromine with difficulty 
(they however strongly reduce an alkaline solution of potassium 
permanganate), the dibromide may be readily prepared from the 
amide and the acid. The dibromo-amide does not melt but chars at 
a higher temperature, the dibromo-acid melts at 12!—121.5° and 
yields «-hydroxybutyric acid when reduced with sodium amalgam. 
a-Hydroxybutenoic acid is one of the strongest organic acids com- 
posed of C, H and O;; its dissociation-constant was found to be 0.046. 
1) Rec. 4. 221. 
2) Preliminary communication Rec. 18. 302. 
