Names | |||
---|---|---|---|
Preferred IUPAC name Cyclohexanone | |||
Other names oxocyclohexane, pimelic ketone, ketohexamethylene, cyclohexyl ketone, ketocyclohexane, hexanon, Hydrol-O, Sextone, K, Anone | |||
Identifiers | |||
3D model (JSmol) | |||
ChEBI | |||
ChEMBL | |||
ChemSpider | |||
DrugBank | |||
ECHA InfoCard | 100.003.302 | ||
EC Number |
| ||
KEGG | |||
PubChem CID | |||
UNII | |||
CompTox Dashboard (EPA) | |||
| |||
| |||
Properties | |||
C6H10O | |||
Molar mass | 98.15 g/mol | ||
Appearance | Colorless liquid [3] | ||
Odor | Peppermint or acetone-like | ||
Density | 0.9478 g/mL, liquid | ||
Melting point | −47 °C (−53 °F; 226 K) [4] | ||
Boiling point | 155.65 °C (312.17 °F; 428.80 K) | ||
8.6 g/100 mL (20 °C) | |||
Solubility in all organic solvents | Miscible | ||
log P | 0.81 | ||
Vapor pressure | 5 mmHg (20 °C) [5] | ||
−62.04·10−6 cm3/mol | |||
Refractive index (nD) | 1.447 | ||
Viscosity | 2.02 cP at 25 °C [6] | ||
Thermochemistry | |||
Std molar entropy (S⦵298) | +229.03 J·K−1·mol−1 | ||
Std enthalpy of formation (ΔfH⦵298) | −270.7 kJ·mol−1 | ||
Std enthalpy of combustion (ΔcH⦵298) | −3519.3 kJ·mol−1 | ||
Hazards | |||
GHS labelling: | |||
Danger [7] | |||
H226, H302, H305, H312, H315, H318, H332 [7] | |||
P280, P305+P351+P338 [7] | |||
NFPA 704 (fire diamond) | |||
Flash point | 44 °C (111 °F; 317 K) | ||
420 °C (788 °F; 693 K) | |||
Explosive limits | 1.1–9.4% | ||
Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 1200 mg/kg (cat, orally); 2362 mg/kg (rat, orally) [8] | ||
LC50 (median concentration) | 8000 ppm (rat, 4 hr) [9] | ||
LCLo (lowest published) | 4706 ppm (mouse, 1.5 hr) [9] | ||
NIOSH (US health exposure limits): | |||
PEL (Permissible) | TWA 50 ppm (200 mg/m3) [5] | ||
REL (Recommended) | TWA 25 ppm (100 mg/m3) [skin] [5] | ||
IDLH (Immediate danger) | 700 ppm [5] | ||
Related compounds | |||
Related ketones | Cyclopentanone, cycloheptanone | ||
Related compounds | Cyclohexanol | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Cyclohexanone is the organic compound with the formula (CH2)5CO. The molecule consists of six-carbon cyclic molecule with a ketone functional group. This colorless oily liquid [3] has a sweet odor reminiscent of benzaldehyde. Over time, samples of cyclohexanone assume a pale yellow color. [10] Cyclohexanone is slightly soluble in water and miscible with common organic solvents. Millions of tonnes are produced annually, mainly as a precursor to nylon. [11]
Cyclohexanone is produced by the oxidation of cyclohexane in air, typically using cobalt catalysts: [11]
This process forms cyclohexanol as a by-product, and this mixture, called "KA Oil" for ketone-alcohol oil, is the main feedstock for the production of adipic acid. The oxidation involves radicals and the hydroperoxide C6H11O2H as an intermediate. In some cases, purified cyclohexanol, obtained by hydration of cyclohexene, is the precursor. Alternatively, cyclohexanone can be produced by the partial hydrogenation of phenol:
This process can also be adjusted to favor the formation of cyclohexanol. [11]
ExxonMobil developed a process in which benzene is hydroalkylated to cyclohexylbenzene. This latter product is oxidized to a hydroperoxide and then cleaved into phenol and cyclohexanone. [12] Therefore, this newer process without producing the acetone by-product appears attractive and is similar to the cumene process as a hydroperoxide is formed and then decomposed to yield two key products. [13]
Cyclohexanone can be prepared from cyclohexanol by oxidation with chromium trioxide (Jones oxidation). An alternative method utilizes the safer and more readily available oxidant sodium hypochlorite. [14] [15]
The great majority of cyclohexanone is consumed in the production of precursors to Nylon 6,6 and Nylon 6. About half of the world's supply is converted to adipic acid, one of two precursors for nylon 6,6. For this application, the KA oil (see above) is oxidized with nitric acid. The other half of the cyclohexanone supply is converted to cyclohexanone oxime. In the presence of sulfuric acid catalyst, the oxime rearranges to caprolactam, a precursor to nylon 6: [11]
In addition to the large scale reactions conducted in service of the polymer industry, many reactions have been developed for cyclohexanone.
In the presence of light, it undergoes alpha-chlorination to give 2-chlorocyclohexanone. [16] It forms a trimethylsilylenol ether upon treatment with trimethylsilylchloride in the presence of base. [17]
It forms an enamine with pyrrolidine. [18]
Treatment with nitrosyl chloride and ethanol in sulfur dioxide gives the oximinecarboxylic ester: [19]
Cyclohexanone has been used in the illicit production of phencyclidine and its analogs [20] and is often subject to purchase restrictions, such as being listed on the Special Surveillance List in the US. [21]
Like cyclohexanol, cyclohexanone is not carcinogenic and is moderately toxic, with a TLV of 25 ppm for the vapor. It is an irritant. [11]
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.
Phenol is an aromatic organic compound with the molecular formula C6H5OH. It is a white crystalline solid that is volatile. The molecule consists of a phenyl group bonded to a hydroxy group. Mildly acidic, it requires careful handling because it can cause chemical burns.
Cyclohexane is a cycloalkane with the molecular formula C6H12. Cyclohexane is non-polar. Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products. Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon.
Cyclohexene is a hydrocarbon with the formula (CH2)4C2H2. It is an example of a cycloalkene. At room temperature, cyclohexene is a colorless liquid with a sharp odor. It has few practical applications.
Cyclohexanol is the organic compound with the formula HOCH(CH2)5. The molecule is related to cyclohexane by replacement of one hydrogen atom by a hydroxyl group. This compound exists as a deliquescent colorless solid with a camphor-like odor, which, when very pure, melts near room temperature. Millions of tonnes are produced annually, mainly as a precursor to nylon.
Adipic acid or hexanedioic acid is the organic compound with the formula (CH2)4(COOH)2. From an industrial perspective, it is the most important dicarboxylic acid: about 2.5 billion kilograms of this white crystalline powder are produced annually, mainly as a precursor for the production of nylon. Adipic acid otherwise rarely occurs in nature, but it is known as manufactured E number food additive E355. Salts and esters of adipic acid are known as adipates.
Caprolactam (CPL) is an organic compound with the formula (CH2)5C(O)NH. This colourless solid is a lactam (a cyclic amide) of caproic acid. Global demand for this compound is approximately five million tons per year, and the vast majority is used to make Nylon 6 filament, fiber, and plastics.
Pimelic acid is the organic compound with the formula HO2C(CH2)5CO2H. Pimelic acid is one CH
2 unit longer than a related dicarboxylic acid, adipic acid, a precursor to many polyesters and polyamides. However compared to adipic acid, pimelic acid is relatively small in importance industrially. Derivatives of pimelic acid are involved in the biosynthesis of the amino acid lysine and the vitamin biotin.
Adiponitrile is an organic compound with the chemical formula (CH2)4(CN)2. This viscous, colourless dinitrile is an important precursor to the polymer nylon 66. In 2005, about one million tonnes of adiponitrile were produced.
1,4-Benzoquinone, commonly known as para-quinone, is a chemical compound with the formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, and hot plastic or formaldehyde. This six-membered ring compound is the oxidized derivative of 1,4-hydroquinone. The molecule is multifunctional: it exhibits properties of a ketone, being able to form oximes; an oxidant, forming the dihydroxy derivative; and an alkene, undergoing addition reactions, especially those typical for α,β-unsaturated ketones. 1,4-Benzoquinone is sensitive toward both strong mineral acids and alkali, which cause condensation and decomposition of the compound.
Hydroperoxides or peroxols are compounds of the form ROOH, where R stands for any group, typically organic, which contain the hydroperoxy functional group. Hydroperoxide also refers to the hydroperoxide anion and its salts, and the neutral hydroperoxyl radical (•OOH) consist of an unbond hydroperoxy group. When R is organic, the compounds are called organic hydroperoxides. Such compounds are a subset of organic peroxides, which have the formula ROOR. Organic hydroperoxides can either intentionally or unintentionally initiate explosive polymerisation in materials with unsaturated chemical bonds.
Crotonaldehyde is a chemical compound with the formula CH3CH=CHCHO. The compound is usually sold as a mixture of the E- and Z-isomers, which differ with respect to the relative position of the methyl and formyl groups. The E-isomer is more common (data given in Table is for the E-isomer). This lachrymatory liquid is moderately soluble in water and miscible in organic solvents. As an unsaturated aldehyde, crotonaldehyde is a versatile intermediate in organic synthesis. It occurs in a variety of foodstuffs, e.g. soybean oils.
Nitrosyl chloride is the chemical compound with the formula NOCl. It is a yellow gas that is commonly encountered as a component of aqua regia, a mixture of 3 parts concentrated hydrochloric acid and 1 part of concentrated nitric acid. It is a strong electrophile and oxidizing agent. It is sometimes called Tilden's reagent, after William A. Tilden, who was the first to produce it as a pure compound.
Isophorone is an α,β-unsaturated cyclic ketone. It is a colorless liquid with a characteristic peppermint-like odor, although commercial samples can appear yellowish. Used as a solvent and as a precursor to polymers, it is produced on a large scale industrially.
Cyclohexenone is an organic compound which is a versatile intermediate used in the synthesis of a variety of chemical products such as pharmaceuticals and fragrances. It is colorless liquid, but commercial samples are often yellow.
In nitrile reduction a nitrile is reduced to either an amine or an aldehyde with a suitable chemical reagent.
Cyclohexanone oxime is an organic compound containing the functional group oxime. This colorless solid is an important intermediate in the production of nylon 6, a widely used polymer.
1-Tetralone is a bicyclic aromatic hydrocarbon and a ketone. In terms of its structure, it can also be regarded as benzo-fused cyclohexanone. It is a colorless oil with a faint odor. It is used as starting material for agricultural and pharmaceutical agents. The carbon skeleton of 1-tetralone is found in natural products such as Aristelegone A (4,7-dimethyl-6-methoxy-1-tetralone) from the family of Aristolochiaceae used in traditional Chinese medicine.
Cyclohexylbenzene is the organic compound with the structural formula C6H5−C6H11. It is a derivative of benzene with a cyclohexyl substituent (C6H11). It is a colorless liquid.
Hydroxymethylation is a chemical reaction that installs the CH2OH group. The transformation can be implemented in many ways and applies to both industrial and biochemical processes.