Acetone cyanohydrin

Last updated
Acetone cyanohydrin
Aceton cyanhydrine Structural formula V.2.svg
Ball and stick model of acetone cyanohydrin Acetone-cyanohydrin-3D-balls.png
Ball and stick model of acetone cyanohydrin
Spacefill model of acetone cyanohydrin Acetone-cyanohydrin-3D-spacefill.png
Spacefill model of acetone cyanohydrin
Names
Preferred IUPAC name
2-Hydroxy-2-methylpropanenitrile [1]
Other names
  • Cyanohydrin-2-propanone [2]
  • α-Hydroxyisobutyronitrile [2]
  • 2-Hydroxy-2-methyl-propionitrile [2]
Identifiers
3D model (JSmol)
3DMet
605391
ChEBI
ChemSpider
DrugBank
ECHA InfoCard 100.000.828 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 200-909-4
KEGG
MeSH acetone+cyanohydrin
PubChem CID
RTECS number
  • OD9275000
UNII
UN number 1541
  • InChI=1S/C4H7NO/c1-4(2,6)3-5/h6H,1-2H3 Yes check.svgY
    Key: MWFMGBPGAXYFAR-UHFFFAOYSA-N Yes check.svgY
  • CC(C)(O)C#N
Properties
C4H7NO
Molar mass 85.106 g·mol−1
AppearanceColourless 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)
1.399
Thermochemistry
−121.7 to −120.1 kJ·mol−1
−2.4514 to −2.4498 MJ·mol−1
Hazards
GHS labelling:
GHS-pictogram-skull.svg GHS-pictogram-pollu.svg
Danger
H300, H310, H330, H410
P260, P273, P280, P284, P301+P310
NFPA 704 (fire diamond)
NFPA 704.svgHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
4
1
2
Flash point 75 °C (167 °F; 348 K)
Explosive limits 2.25–11%
Lethal dose or concentration (LD, LC):
  • 15.8 mg·kg−1(dermal, rabbit)
  • 18.65 mg·kg−1(oral, rat)
NIOSH (US health exposure limits):
PEL (Permissible)
None [2]
REL (Recommended)
C 1 ppm (4 mg·m−3) [15-minute] [2]
IDLH (Immediate danger)
N.D. [2]
Safety data sheet (SDS) fishersci.com
Related compounds
Related alkanenitriles
Related compounds
DBNPA
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

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. It liberates hydrogen cyanide easily, so it is used as a source of such. For this reason, this cyanohydrin is also highly toxic.

Contents

Preparation

In the laboratory, this compound may be prepared by treating sodium cyanide with acetone, followed by acidification: [3]

Synthesis of acetone cyanohydrin.png

Considering the high toxicity of acetone cyanohydrin, a lab scale production has been developed using a microreactor-scale flow chemistry [4] to avoid needing to manufacture and store large quantities of the reagent. Alternatively, 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, one that is nonetheless suitable for most syntheses. [5]

Reactions

Acetone cyanohydrin is an intermediate en route to methyl methacrylate. [6] Treatment with sulfuric acid gives the sulfate ester of the methacrylamide,[ clarification needed ] methanolysis of which gives ammonium bisulfate and methyl methacrylate. [7]

It is used as a surrogate in place of HCN, as illustrated by its use as a precursor to lithium cyanide: [8]

(CH3)2C(OH)CN + LiH → (CH3)2CO + LiCN + H2

In transhydrocyanation, an equivalent of HCN is transferred from acetone cyanohydrin to another acceptor, with acetone as byproduct. The transfer is an equilibrium process, initiated by base. The reaction can be driven by trapping reactions or by the use of a superior HCN acceptor, such as an aldehyde. [9] In the hydrocyanation reaction of butadiene, the transfer is irreversible. [10]

Natural occurrence

Cassava tubers contain linamarin, a glucoside of acetohydrin, and the enzyme linamarase for hydrolysing the glucoside. Crushing the tubers releases these compounds and produces acetone cyanohydrin.

Safety

Acetone cyanohydrin is classified as an extremely hazardous substance in the US Emergency Planning and Community Right-to-Know Act and carries an RCRA P069 waste code. The principal hazards of acetone cyanohydrin arise from its ready decomposition on contact with water, which releases highly toxic hydrogen cyanide.

Related Research Articles

<span class="mw-page-title-main">Ketone</span> Organic compounds of the form >C=O

In organic chemistry, a ketone is an organic compound with the structure R−C(=O)−R', where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group −C(=O)−. The simplest ketone is acetone, with the formula (CH3)2CO. Many ketones are of great importance in biology and in industry. Examples include many sugars (ketoses), many steroids, and the solvent acetone.

<span class="mw-page-title-main">Hydrogen cyanide</span> Highly toxic chemical with the formula HCN

Hydrogen cyanide is a chemical compound with the formula HCN and structural formula H−C≡N. It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at 25.6 °C (78.1 °F). HCN is produced on an industrial scale and is a highly valued precursor to many chemical compounds ranging from polymers to pharmaceuticals. Large-scale applications are for the production of potassium cyanide and adiponitrile, used in mining and plastics, respectively. It is more toxic than solid cyanide compounds due to its volatile nature.

<span class="mw-page-title-main">Sodium cyanide</span> Chemical compound

Sodium cyanide is a poisonous compound with the formula NaCN. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.

<span class="mw-page-title-main">Potassium ferricyanide</span> Chemical compound

Potassium ferricyanide is the chemical compound with the formula K3[Fe(CN)6]. This bright red salt contains the octahedrally coordinated [Fe(CN)6]3− ion. It is soluble in water and its solution shows some green-yellow fluorescence. It was discovered in 1822 by Leopold Gmelin.

Mesitylene or 1,3,5-trimethylbenzene is a derivative of benzene with three methyl substituents positioned symmetrically around the ring. The other two isomeric trimethylbenzenes are 1,2,4-trimethylbenzene (pseudocumene) and 1,2,3-trimethylbenzene (hemimellitene). All three compounds have the formula C6H3(CH3)3, which is commonly abbreviated C6H3Me3. Mesitylene is a colorless liquid with sweet aromatic odor. It is a component of coal tar, which is its traditional source. It is a precursor to diverse fine chemicals. The mesityl group (Mes) is a substituent with the formula C6H2Me3 and is found in various other compounds.

<span class="mw-page-title-main">Cyanohydrin</span> Functional group in organic chemistry

In organic chemistry, a cyanohydrin or hydroxynitrile is a functional group found in organic compounds in which a cyano and a hydroxy group are attached to the same carbon atom. The general formula is R2C(OH)CN, where R is H, alkyl, or aryl. Cyanohydrins are industrially important precursors to carboxylic acids and some amino acids. Cyanohydrins can be formed by the cyanohydrin reaction, which involves treating a ketone or an aldehyde with hydrogen cyanide (HCN) in the presence of excess amounts of sodium cyanide (NaCN) as a catalyst:

In organic chemistry, a nitrile is any organic compound that has a −C≡N functional group. The name of the compound is composed of a base, which includes the carbon of the −C≡N, suffixed with "nitrile", so for example CH3CH2C≡N is called "propionitrile". The prefix cyano- is used interchangeably with the term nitrile in industrial literature. Nitriles are found in many useful compounds, including methyl cyanoacrylate, used in super glue, and nitrile rubber, a nitrile-containing polymer used in latex-free laboratory and medical gloves. Nitrile rubber is also widely used as automotive and other seals since it is resistant to fuels and oils. Organic compounds containing multiple nitrile groups are known as cyanocarbons.

<span class="mw-page-title-main">Diazomethane</span> Simplest diazo compound and methylating agent

Diazomethane is an organic chemical compound with the formula CH2N2, discovered by German chemist Hans von Pechmann in 1894. It is the simplest diazo compound. In the pure form at room temperature, it is an extremely sensitive explosive yellow gas; thus, it is almost universally used as a solution in diethyl ether. The compound is a popular methylating agent in the laboratory, but it is too hazardous to be employed on an industrial scale without special precautions. Use of diazomethane has been significantly reduced by the introduction of the safer and equivalent reagent trimethylsilyldiazomethane.

In organic chemistry, hydrocyanation is a process for conversion of alkenes to nitriles. The reaction involves the addition of hydrogen cyanide and requires a catalyst. This conversion is conducted on an industrial scale for the production of precursors to nylon.

<span class="mw-page-title-main">Methyl methacrylate</span> Chemical compound

Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA).

<span class="mw-page-title-main">Methyl isobutyl ketone</span> Chemical compound

Methyl isobutyl ketone (MIBK, 4-methylpentan-2-one) is an organic compound with the condensed chemical formula (CH3)2CHCH2C(O)CH3. This ketone is a colourless liquid that is used as a solvent for gums, resins, paints, varnishes, lacquers, and nitrocellulose.

<span class="mw-page-title-main">Mesityl oxide</span> Chemical compound

Mesityl oxide is a α,β-unsaturated ketone with the formula CH3C(O)CH=C(CH3)2. This compound is a colorless, volatile liquid with a honey-like odor.

<span class="mw-page-title-main">Thiophenol</span> Chemical compound

Thiophenol is an organosulfur compound with the formula C6H5SH, sometimes abbreviated as PhSH. This foul-smelling colorless liquid is the simplest aromatic thiol. The chemical structures of thiophenol and its derivatives are analogous to phenols. An exception is the oxygen atom in the hydroxyl group (-OH) bonded to the aromatic ring is replaced by a sulfur atom. The prefix thio- implies a sulfur-containing compound and when used before a root word name for a compound which would normally contain an oxygen atom, in the case of 'thiol' that the alcohol oxygen atom is replaced by a sulfur atom.

<span class="mw-page-title-main">Methacrylic acid</span> Chemical compound

Methacrylic acid, abbreviated MAA, is an organic compound with the formula CH2=C(CH3)CO2H. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced industrially on a large scale as a precursor to its esters, especially methyl methacrylate (MMA), and to poly(methyl methacrylate) (PMMA).

<span class="mw-page-title-main">Trimethylsilyl cyanide</span> Chemical compound

Trimethylsilyl cyanide is the chemical compound with the formula (CH3)3SiCN. This volatile liquid consists of a cyanide group, that is CN, attached to a trimethylsilyl group. The molecule is used in organic synthesis as the equivalent of hydrogen cyanide. It is prepared by the reaction of lithium cyanide and trimethylsilyl chloride:

Diisopropylamine is a secondary amine with the chemical formula (Me2CH)2NH (Me = methyl). Diisopropylamine is a colorless liquid with an ammonia-like odor. Its lithium derivative, lithium diisopropylamide, known as LDA is a widely used reagent.

<span class="mw-page-title-main">Diethylaluminium cyanide</span> Chemical compound

Diethylaluminium cyanide is the organoaluminium compound with formula ( 2AlCN)n. This colorless compound is usually handled as a solution in toluene. It is a reagent for the hydrocyanation of α,β-unsaturated ketones.

<span class="mw-page-title-main">Chloromethyl methyl ether</span> Chemical compound

Chloromethyl methyl ether (CMME) is a compound with formula CH3OCH2Cl. A colorless liquid, it is a chloroalkyl ether. It is used as an alkylating agent. In organic synthesis, it is used for introducing the methoxymethyl ether (MOM) protecting group, and is thus often called MOM-Cl or MOM chloride. It also finds application as a chloromethylating agent in some variants of the Blanc chloromethylation.

In organic synthesis, cyanation is the attachment or substitution of a cyanide group on various substrates. Such transformations are high-value because they generate C-C bonds. Furthermore nitriles are versatile functional groups.

<span class="mw-page-title-main">Lithium cyanide</span> Toxic crystalline salt

Lithium cyanide is an inorganic compound with the chemical formula LiCN. It is a toxic, white coloured, hygroscopic, water-soluble salt that finds only niche uses.

References

  1. "acetone cyanohydrin - Compound Summary". PubChem Compound. USA: National Center for Biotechnology Information. 16 September 2004. Identification. Retrieved 8 June 2012.
  2. 1 2 3 4 5 6 NIOSH Pocket Guide to Chemical Hazards. "#0005". National Institute for Occupational Safety and Health (NIOSH).
  3. Cox, R. F. B.; Stormont, R. T. "Acetone Cyanohydrin". Organic Syntheses ; Collected Volumes, vol. 2, p. 7.
  4. Heugebaert, Thomas S. A.; Roman, Bart I.; De Blieck, Ann; Stevens, Christian V. (2010-08-11). "A safe production method for acetone cyanohydrin". Tetrahedron Letters. 51 (32): 4189–4191. doi:10.1016/j.tetlet.2010.06.004.
  5. Wagner, E. C.; Baizer, Manuel. "5,5-Dimethylhydantoin". Organic Syntheses ; Collected Volumes, vol. 3, p. 323.
  6. Wiley, Richard H.; Waddey, Walter E. (1949). "Methacrylamide". Organic Syntheses. 29: 61. doi:10.15227/orgsyn.029.0061.
  7. Bauer, William Jr. "Methacrylic Acid and Derivatives". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_441. ISBN   978-3527306732..
  8. Tom Livinghouse (1981). "Trimethylsilyl Cyanide: Cyanosilylation of p-Benzoquinone". Org. Synth. 60: 126. doi:10.15227/orgsyn.060.0126.
  9. Haroutounian, Serkos A. (2001). "Acetone Cyanohydrin". Encyclopedia of Reagents for Organic Synthesis. eEROS. doi:10.1002/047084289X.ra014. ISBN   0471936235.
  10. Bini, L.; Müller, C.; Wilting, J.; von Chrzanowski, L.; Spek, A. L.; Vogt, D. (October 2007). "Highly selective hydrocyanation of butadiene toward 3-pentenenitrile". J. Am. Chem. Soc. 129 (42): 12622–12623. doi:10.1021/ja074922e. hdl: 1874/26892 . PMID   17902667.