67. Acetone Cyanohydrin

Nomenclature

CAS number: 75-86-5
2-Hydroxy-2-methylpropanenitrile; 2-methyllactonitrile; α-hydroxyisobutyronitrile.
C4H7NO; mol wt 85.10.
C 56.45%, H 8.29%, N 16.46%, O 18.80%.

Description and references

Prepd by adding acetone to sodium or potassium cyanide in water and treating with H2SO4 at below 20°: Welch, Clemo, J. Chem. Soc. 1928, 2629; Cox, Stormont, Org. Synth. coll. vol. II, 7 (1943). Continuous production from HCN and aq acetone: G. Barsky, US 2731490 (1956). Toxicity study: H. F. Smyth et al., Am. Ind. Hyg. Assoc. J. 23, 95 (1962).

Chemical structure

Properties

Liquid. Poisonous. d425 0.9267; d419 0.932. mp 19°. bp15 81°; bp20 88-90°; bp23 82°; bp760 95°. nD19 1.40002; nD15 1.3980. Freely sol in water and in the usual organic solvents. Practically insol in petr ether and carbon disulfide. Decomposes readily to form hydrogen cyanide, q.v., which is highly toxic. LD50 orally in rats: 0.17 g/kg (Smyth).

Caution

Potential symptoms of overexposure are irritation of eyes, skin, respiratory system; dizziness, weakness, headache, confusion, convulsions; liver, kidney injury; pulmonary edema, asphyxia. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 4.

Use

In preparative organic chemistry for transcyanohydrination, such as preparing the 17-monocyanohydrin of a 3,17-diketo steroid by hydrogen cyanide exchange with the reagent, e.g. Ercoli, de Ruggieri, J. Am. Chem. Soc. 75, 650 (1953).