Acetone cyanohydrin

Structural formula
General
Surname	Acetone cyanohydrin
other names	2-hydroxy-2-methylpropionitrile 2-cyanopropan-2-ol 2-methyl-lactonitrile
Molecular formula	C 4 H 7 NO
Brief description	colorless to yellowish liquid with a faint bitter almond odor
External identifiers / databases
CAS number 75-86-5 EC number 200-909-4 ECHA InfoCard 100,000,828 PubChem 6406 ChemSpider 6166 DrugBank DB02203 Wikidata Q222936
properties
Molar mass	85.11 g mol −1
Physical state	liquid
density	0.93 g cm −3 (20 ° C)
Melting point	−20 ° C
boiling point	82 ° C (30.7 hPa)
Vapor pressure	1.1 h Pa (20 ° C)
solubility	miscible with water
Refractive index	1.3992 (20 ° C)
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 300-310-330-370-410 P: 280-284-302 + 350-403 + 233-501
Toxicological data	18.65 mg kg −1 ( LD 50 ,  rat ,  oral )
Thermodynamic properties
ΔH f 0	−120.9 kJ / mol
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . Refractive index: Na-D line , 20 ° C

Acetone cyanohydrin is a colorless, water-soluble liquid with a slight smell of hydrocyanic acid , which is mostly yellow in color due to impurities resulting from the synthesis . Acetone cyanohydrin is an important C4 component in the chemical industry. It is the nitrile of 2-hydroxyisobutyric acid .

Extraction and presentation

Acetone cyanohydrin is produced by the addition of hydrogen cyanide to acetone .

use

Acetone cyanohydrin is used for the production of methyl methacrylate (starting material for the production of Plexiglas ) and azobisisobutyronitrile as well as a masking agent. Acetone cyanohydrin is also used in the production of insecticides, pharmaceutical products and fragrances and flavorings. The C4 building block hydroxyisobutyric acid amide can be synthesized from acetone cyanohydrin by hydrolysis .

Biological importance

Plants such as B. flax , cassava , lima beans or the rubber tree contain the cyanogenic glycoside linamarine , which is converted into acetone cyanohydrin and then into hydrogen cyanide as a defense strategy if the plants are damaged.

safety instructions

Acetone cyanohydrin breaks down easily into acetone and the highly toxic hydrocyanic acid when heated and in contact with alkaline substances (soap). Acetone cyanohydrin penetrates the skin.

Individual evidence

1. ↑ ^{a b c d e f g h} Entry on acetone cyanohydrin in the GESTIS substance database of the IFA , accessed on January 10, 2017(JavaScript required) .
2. ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compounds, pp. 3-4.
3. ↑ Entry on 2-hydroxy-2-methylpropionitrile in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
4. ↑ Entry on acetone cyanohydrin in the ChemIDplus database of the United States National Library of Medicine (NLM)
5. ↑ David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 90th edition. (Internet version: 2010), CRC Press / Taylor and Francis, Boca Raton, FL, Standard Thermodynamic Properties of Chemical Substances, pp. 5-26.
6. ↑ Entry on cyanohydrins. In: Römpp Online . Georg Thieme Verlag, accessed on May 27, 2014.
7. ↑ Entry on cyanogenic glycosides. In: Römpp Online . Georg Thieme Verlag, accessed on May 27, 2014.