Acetone cyanohydrin

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Acetone cyanohydrin
Skeletal formula of acetone cyanohydrin
Ball and stick model of acetone cyanohydrin Spacefill model of acetone cyanohydrin
Identifiers
CAS number 75-86-5 YesY
PubChem 6406
ChemSpider 6166 YesY
EC number 200-909-4
UN number 1541
DrugBank DB02203
KEGG C02659 YesY
MeSH acetone+cyanohydrin
ChEBI CHEBI:15348 YesY
RTECS number OD9275000
Beilstein Reference 605391
3DMet B00479
Jmol-3D images Image 1
Properties
Molecular formula C4H7NO
Molar mass 85.10 g mol−1
Appearance Colourless liquid
Density 932 mg mL−1
Melting point −21.2 °C; −6.3 °F; 251.9 K
Boiling point 95 °C (203 °F; 368 K)
Vapor pressure 2 kPa (at 20 °C)
Refractive index (nD) 1.399
Thermochemistry
Std enthalpy of
formation
ΔfHo298
−121.7–−120.1 kJ mol−1
Std enthalpy of
combustion
ΔcHo298
−2.4514–−2.4498 MJ mol−1
Hazards
MSDS fishersci.com
GHS pictograms The skull-and-crossbones pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) The environment pictogram in the Globally Harmonized System of Classification and Labelling of Chemicals (GHS)
GHS signal word DANGER
GHS hazard statements H300, H310, H330, H410
GHS precautionary statements P260, P273, P280, P284, P301+310
EU Index 608-004-00-X
EU classification Very Toxic T+ Dangerous for the Environment (Nature) N
R-phrases R26/27/28, R50
S-phrases (S1/2), S27, S45
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 4: Very short exposure could cause death or major residual injury. E.g., VX gas Reactivity code 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g., phosphorus Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 75 °C (167 °F; 348 K)
LD50
  • 15.8 mg kg−1 (dermal, rabbit)
  • 18.65 mg kg−1 (oral, rat)
Related compounds
Related alkanenitriles
Related compounds DBNPA
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Acetone cyanohydrin (ACH) is an organic compound used in the production of methyl methacrylate, the monomer of the transparent plastic polymethyl methacrylate (PMMA), also known as acrylic.

Preparation[edit]

The compound is generated as part of the acetone cyanohydrin route to methyl methacrylate. It is treated with sulfuric acid to give the sulfate ester of the methacrylamide, methanolysis of which gives ammonium bisulfate and MMA.[2] In the laboratory, this compound may be prepared by reacting sodium cyanide with acetone, followed by acidification:[3]

Synthesis of acetone cyanohydrin.png

A simplified procedure involves the action of sodium or potassium cyanide on the sodium bisulfite adduct of acetone prepared in situ. This gives a less pure product that is suitable for most syntheses.[4]

Natural occurrence[edit]

Cassava tubers contain linamarin, a glucoside of acetohydrin, and the enzyme linamarinase for hydrolysing the glucoside. Crushing the tubers releases these compounds and produces acetone cyanohydrin, which is potentially lethally toxic.

Safety[edit]

Acetone cyanohydrin is classified as an extremely hazardous substance in the US Emergency Planning and Community Right-to-Know Act. The principal hazards of acetone cyanohydrin arise from its ready decomposition on contact with water, which releases highly toxic hydrogen cyanide.

References[edit]

  1. ^ "acetone cyanohydrin - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification. Retrieved 8 June 2012. 
  2. ^ Bauer, Jr., William (2002), "Ullmann's Encyclopedia of Industrial Chemistry", Ullmann's Encyclopedia of Industrial Chemistry (Weinheim: Wiley-VCH), doi:10.1002/14356007.a16_441, ISBN 3-527-30673-0  |chapter= ignored (help).
  3. ^ Cox, R. F. B.; Stormont, R. T., "Acetone Cyanohydrin", Org. Synth. ; Coll. Vol. 2: 7 
  4. ^ Wagner, E. C.; Baizer, Manuel, "5,5-Dimethylhydantoin", Org. Synth. ; Coll. Vol. 3: 323 

External links[edit]