428. α-Aminobutyric Acid

Nomenclature

CAS number: 2835-81-6
2-Aminobutanoic acid; α-amino-n-butyric acid.
C4H9NO2; mol wt 103.12.
C 46.59%, H 8.80%, N 13.58%, O 31.03%.

Description and references

Prepn of the dl-form from α-bromobutyric acid and ammonia: Fisher, Mounegrat, Ber. 33, 2388 (1900); from potassium cyanide, ammonium chloride and propionaldehyde: Zelinsky, Stadnikow, Ber. 41, 2062 (1908); by reduction of α-oxobutyric acid: Knoop, Oesterlin, Z. Physiol. Chem. 148, 305 (1925); from α-ethylacetoacetic ester and hydrazoic acid: Schmidt, Ber. 57, 706 (1924). The l(+)-form has been isolated from proteins: Oikawa, Chem. Zentralbl. 1926, 1, 148. Configuration: Clough, J. Chem. Soc. 113, 544, 551; Levene, Chem. Rev. 2, 203 (1926); Vogler, Helv. Chim. Acta 30, 1766 (1947).

Chemical structure

Derivative

dl-Form.

Properties

Crystals, mp 304° (begins to sublime when heated above 300°). Sol in water. One liter of water will dissolve 210.5 g at 25°. Sparingly sol in alcohol. One liter of boiling ethanol dissolves about 1.8 g. Insol in ether.

Derivative

dl-Form ethyl ester.

Properties

Viscous liquid. bp11 61°. Sol in water and in organic solvents.

Derivative

l-Form.

Properties

Leaflets from dil alc. Sweet taste. mp 270-280° (depending on speed of heating, see Vogler, loc. cit.). [M]D +21.2° (5N HCl); [M]D +43.3° (glacial acetic acid). [α]D16 +8.40° (c = 4); [α]D16 +18.65° (c = 4.8 in 6N HCl).

Derivative

l-Form hydrochloride.

Properties

Needles; [α]D19 +12.90° (c = 3.64). Readily sol in water.