Acetyl cyanide

Last updated
Acetyl cyanide
Acetyl cyanide.png
Names
Preferred IUPAC name
Acetyl cyanide [1]
Systematic IUPAC name
Ethanoyl cyanide
Other names
2-Oxopropanenitrile [1]
Pyruvonitrile
Propanenitrile, 2-oxo-
α-Oxopropionitrile
Oxopropionitrile
Oxypropionitrile
Pyruvic acid nitrile
2-Oxopropionitrile
2-Oxopropiononitrile
Identifiers
3D model (JSmol)
1737633
ChemSpider
ECHA InfoCard 100.010.146 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 211-159-2
PubChem CID
UNII
  • InChI=1S/C3H3NO/c1-3(5)2-4/h1H3 Yes check.svgY
    Key: QLDHWVVRQCGZLE-UHFFFAOYSA-N Yes check.svgY
  • CC(=O)C#N
Properties
C3H3NO
Molar mass 69.063 g·mol−1
AppearanceClear, yellow liquid
Density 0.9745 g/cm3
Boiling point 92.3 °C (198.1 °F; 365.4 K)
Vapor pressure 51.93 mmHg
1.3764
40.86 Å2
Hazards
Occupational safety and health (OHS/OSH):
Ingestion hazards
Toxic if swallowed
Inhalation hazards
Toxic if inhaled. Causes respiratory tract irritation
Eye hazards
Causes eye irritation
Skin hazards
May be harmful if absorbed through skin. Causes skin irritation.
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-skull.svg
Danger
H225, H301, H315, H331, H335, H401, H412
P210, P261, P273, P301+P310, P311
NFPA 704 (fire diamond)
NFPA 704.svgHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 3: Liquids and solids that can be ignited under almost all ambient temperature conditions. Flash point between 23 and 38 °C (73 and 100 °F). E.g. gasolineInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
3
0
Flash point 14.44 °C (57.99 °F; 287.59 K)
Safety data sheet (SDS) External MSDS
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 ?)

Acetyl cyanide is the organic compound with the formula CH3C(O)CN. It is an acyl cyanide. Acetyl cyanide is a colorless liquid. [2]

Contents

Structure

Its structure was determined through the use of electron diffraction intensities and rotational spectroscopy. [3]

Reactions

Two main types of reactions can occur with acetyl cyanide as a reactant; aldol condensation and enolate substitution. Aldol condensation can occur when acetyl cyanide reacts with (Z)-but-2-enal to form (2E,4E)-hexa-2,4-dienoyl cyanide:

Aldol condensation of Acetyl cyanide.png

The photochemical and thermal reactions of acetyl cyanide have been extensively studied. For example, formyl cyanide does not undergo unimolecular decomposition to HCN and CO spontaneously. However, acetyl cyanide, also a member of this family, breaks down through this unimolecular decomposition at 470 °C. This reaction occurs through decarbonylation. This division of the molecule to a ketone and hydrogen cyanide were noted to be under competitive circumstances. This caused a study of the thermal unimolecular reactions that acetyl cyanide undergoes.

The unimolecular decompositions that acetyl cyanide undergo have been confirmed to be less energetically favorable than the molecule undergoing isomerization to acetyl isocyanide. However, through other photolysis experiments have resulted in the formation of a CN radical through acetyl cyanide decomposing into CH3CO + CN or CH3COCN. [4]

Synthesis

Acetyl cyanide is prepared from acetyl chloride and cyanide sources, often in the presence of copper catalysts. [2] Acetyl cyanide is also synthesized at 350 °C from ketene and hydrogen cyanide. [4]

Acyl cyanide synthesis.png

Related Research Articles

<span class="mw-page-title-main">Cyanide</span> Any molecule with a cyano group (–C≡N)

In chemistry, cyanide is a chemical compound that contains a C≡N functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom.

<span class="mw-page-title-main">Chemical bond</span> Association of atoms to form chemical compounds

A chemical bond is the association of atoms or ions to form molecules, crystals, and other structures. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds, or some combination of these effects. Chemical bonds are described as having different strengths: there are "strong bonds" or "primary bonds" such as covalent, ionic and metallic bonds, and "weak bonds" or "secondary bonds" such as dipole–dipole interactions, the London dispersion force, and hydrogen bonding.

<span class="mw-page-title-main">Aldehyde</span> Organic compound containing the functional group R−CH=O

In organic chemistry, an aldehyde is an organic compound containing a functional group with the structure R−CH=O. The functional group itself can be referred to as an aldehyde but can also be classified as a formyl group. Aldehydes are a common motif in many chemicals important in technology and biology.

<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 highly toxic 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. A solution of hydrogen cyanide in water, represented as HCN, is called hydrocyanic acid. The salts of the cyanide anion are known as cyanides.

<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.

Cyanogen is the chemical compound with the formula (CN)2. The simplest stable carbon nitride, it is a colorless and highly toxic gas with a pungent odor. The molecule is a pseudohalogen. Cyanogen molecules consist of two CN groups ‒ analogous to diatomic halogen molecules, such as Cl2, but far less oxidizing. The two cyano groups are bonded together at their carbon atoms: N≡C‒C≡N, though other isomers have been detected. The name is also used for the CN radical, and hence is used for compounds such as cyanogen bromide (NCBr) (but see also Cyano radical). When burned at increased pressure with oxygen, it is possible to get a blue tinted flame, the temperature of which is about 4800°C (a higher temperature is possible with ozone). It is as such regarded as the gas with the second highest temperature of burning (after dicyanoacetylene).

<span class="mw-page-title-main">Aldol condensation</span> Type of chemical reaction

An aldol condensation is a condensation reaction in organic chemistry in which two carbonyl moieties react to form a β-hydroxyaldehyde or β-hydroxyketone, and this is then followed by dehydration to give a conjugated enone.

An isocyanide is an organic compound with the functional group –N+≡C. It is the isomer of the related nitrile (–C≡N), hence the prefix is isocyano. The organic fragment is connected to the isocyanide group through the nitrogen atom, not via the carbon. They are used as building blocks for the synthesis of other compounds.

<span class="mw-page-title-main">Cyanate</span> Anion with formula OCN and charge –1

The cyanate ion is an anion with the chemical formula OCN. It is a resonance of three forms: [O−C≡N] (61%) ↔ [O=C=N] (30%) ↔ [O+≡C−N2−] (4%).

The Claisen condensation is a carbon–carbon bond forming reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base. The reaction produces a β-keto ester or a β-diketone. It is named after Rainer Ludwig Claisen, who first published his work on the reaction in 1887. The reaction has often been displaced by diketene-based chemistry, which affords acetoacetic esters.

The E1cB elimination reaction is a type of elimination reaction which occurs under basic conditions, where the hydrogen to be removed is relatively acidic, while the leaving group is a relatively poor one. Usually a moderate to strong base is present. E1cB is a two-step process, the first step of which may or may not be reversible. First, a base abstracts the relatively acidic proton to generate a stabilized anion. The lone pair of electrons on the anion then moves to the neighboring atom, thus expelling the leaving group and forming a double or triple bond. The name of the mechanism - E1cB - stands for Elimination Unimolecular conjugate Base. Elimination refers to the fact that the mechanism is an elimination reaction and will lose two substituents. Unimolecular refers to the fact that the rate-determining step of this reaction only involves one molecular entity. Finally, conjugate base refers to the formation of the carbanion intermediate, which is the conjugate base of the starting material.

<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:

<span class="mw-page-title-main">Tetracyanoethylene</span> Organic compound with formula C2(CN)4

Tetracyanoethylene (TCNE) is organic compound with the formula C2(CN)4. It is a colorless solid, although samples are often off-white. It is an important member of the cyanocarbons.

<span class="mw-page-title-main">Molecular solid</span> Solid consisting of discrete molecules

A molecular solid is a solid consisting of discrete molecules. The cohesive forces that bind the molecules together are van der Waals forces, dipole–dipole interactions, quadrupole interactions, π–π interactions, hydrogen bonding, halogen bonding, London dispersion forces, and in some molecular solids, coulombic interactions. Van der Waals, dipole interactions, quadrupole interactions, π–π interactions, hydrogen bonding, and halogen bonding are typically much weaker than the forces holding together other solids: metallic, ionic, and network solids.

A carbon–nitrogen bond is a covalent bond between carbon and nitrogen and is one of the most abundant bonds in organic chemistry and biochemistry.

Hydrogen isocyanide is a chemical with the molecular formula HNC. It is a minor tautomer of hydrogen cyanide (HCN). Its importance in the field of astrochemistry is linked to its ubiquity in the interstellar medium.

Methylene is an organic compound with the chemical formula CH
2
. It is a colourless gas that fluoresces in the mid-infrared range, and only persists in dilution, or as an adduct.

Cyanometallates or cyanometalates are a class of coordination compounds, most often consisting only of cyanide ligands. Most are anions. Cyanide is a highly basic and small ligand, hence it readily saturates the coordination sphere of metal ions. The resulting cyanometallate anions are often used as building blocks for more complex structures called coordination polymers, the best known example of which is Prussian blue, a common dyestuff.

Structural chemistry is a part of chemistry and deals with spatial structures of molecules and solids. For structure elucidation a range of different methods is used. One has to distinguish between methods that elucidate solely the connectivity between atoms (constitution) and such that provide precise three dimensional information such as atom coordinates, bond lengths and angles and torsional angles.

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

Bicyclohexyl, also known as dicyclohexyl or bicyclohexane, is an organic chemical with the formula C12H22 and a molecular mass of 166.303 g mol−1. It is a nonvolatile liquid at room temperature, with a boiling point of 227 °C (441 °F). Its structure consists of two cyclohexane rings joined by a single carbon-carbon bond.

References

  1. 1 2 Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. pp. 796–797, 903. doi:10.1039/9781849733069-FP001. ISBN   978-0-85404-182-4.
  2. 1 2 Morris, Joel (2001). "Acetyl Cyanide". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.ra026. ISBN   0-471-93623-5.
  3. Sugié, Masaaki; Kuchitsu, Kozo (1974). "Molecular structure of acetyl cyanide as studied by gas electron diffraction". Journal of Molecular Structure. 20 (3): 437–448. Bibcode:1974JMoSt..20..437S. doi:10.1016/0022-2860(74)85121-5.
  4. 1 2 R. Sumathi; Minh Tho Nguyen (1998). "Theoretical Study on Unimolecular Reactions of Acetyl Cyanide and Acetyl Isocyanide" (PDF). J. Phys. Chem. A. 102 (2): 412–421. Bibcode:1998JPCA..102..412S. doi:10.1021/jp9724582. Archived from the original (PDF) on 17 April 2007. Retrieved 7 March 2022.

Further reading