P-Cymene

Last updated
p-Cymene
Skeletal formula P-Cymol.svg
Skeletal formula
Ball-and-stick model Cymene-3D-balls.png
Ball-and-stick model
Names
Preferred IUPAC name
1-Methyl-4-(propan-2-yl)benzene [1]
Other names
para-Cymene
4-Isopropyltoluene
4-Methylcumene
Paracymene
Identifiers
3D model (JSmol)
3DMet
1903377
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.002.542 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 202-796-7
305912
KEGG
PubChem CID
RTECS number
  • GZ5950000
UNII
UN number 2046
  • InChI=1S/C10H14/c1-8(2)10-6-4-9(3)5-7-10/h4-8H,1-3H3 Yes check.svgY
    Key: HFPZCAJZSCWRBC-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C10H14/c1-8(2)10-6-4-9(3)5-7-10/h4-8H,1-3H3
    Key: HFPZCAJZSCWRBC-UHFFFAOYAD
  • c1cc(ccc1C(C)C)C
Properties
C10H14
Molar mass 134.222 g·mol−1
AppearanceColourless liquid
Density 0.857 g/cm3
Melting point −68 °C (−90 °F; 205 K)
Boiling point 177 °C (351 °F; 450 K)
23.4 mg/L
−1.028×10−4 cm3/mol
1.4908 (at 20 °C) [2]
Hazards
GHS labelling:
GHS-pictogram-flamme.svg GHS-pictogram-silhouette.svg GHS-pictogram-pollu.svg
Danger
H226, H304, H411
P210, P233, P240, P241, P242, P243, P273, P280, P301+P310, P303+P361+P353, P331, P370+P378, P391, P403+P235, P405, P501
Flash point 47 °C (117 °F; 320 K)
435 °C (815 °F; 708 K)
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 ?)

p-Cymene is a naturally occurring aromatic organic compound. It is classified as an alkylbenzene related to monocyclic monoterpenes. [3] Its structure consists of a benzene ring para-substituted with a methyl group and an isopropyl group. p-Cymene is insoluble in water, but miscible with organic solvents.

Contents

Isomers and production

In addition to p-cymene, two less common geometric isomers are o-cymene, in which the alkyl groups are ortho-substituted, and m-cymene, in which they are meta-substituted. p-Cymene is the only natural isomer, as expected from the terpene rule. All three isomers form the group of cymenes.

Cymene is also produced by alkylation of toluene with propene. [4]

It is a constituent of a number of essential oils, most commonly the oil of cumin and thyme. Significant amounts are formed in sulfite pulping process from the wood terpenes.

p-Cymene is a common ligand for ruthenium. The parent compound is [(η6-cymene)RuCl2]2. This half-sandwich compound is prepared by the reaction of ruthenium trichloride with the terpene α-phellandrene. The osmium complex is also known. [5]

Hydrogenation gives the saturated derivative p-menthane.

Related Research Articles

Cyclohexa-1,3-diene (also known as Benzane) is an organic compound with the formula (C2H4)(CH)4. It is a colorless, flammable liquid. Its refractive index is 1.475 (20 °C, D). A naturally occurring derivative of cyclohexa-1,3-diene is terpinene, a component of pine oil.

<span class="mw-page-title-main">2,2,4-Trimethylpentane</span> Chemical compound

2,2,4-Trimethylpentane, also known as isooctane or iso-octane, is an organic compound with the formula (CH3)3CCH2CH(CH3)2. It is one of several isomers of octane (C8H18). This particular isomer is the standard 100 point on the octane rating scale (the zero point is n-heptane). It is an important component of gasoline, frequently used in relatively large proportions (around 10%) to increase the knock resistance of fuel.

Aromatization is a chemical reaction in which an aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene. Aromatization includes the formation of heterocyclic systems.

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

1,3,5,7-Cyclooctatetraene (COT) is an unsaturated derivative of cyclooctane, with the formula C8H8. It is also known as [8]annulene. This polyunsaturated hydrocarbon is a colorless to light yellow flammable liquid at room temperature. Because of its stoichiometric relationship to benzene, COT has been the subject of much research and some controversy.

<span class="mw-page-title-main">Ruthenium(III) chloride</span> Chemical compound

Ruthenium(III) chloride is the chemical compound with the formula RuCl3. "Ruthenium(III) chloride" more commonly refers to the hydrate RuCl3·xH2O. Both the anhydrous and hydrated species are dark brown or black solids. The hydrate, with a varying proportion of water of crystallization, often approximating to a trihydrate, is a commonly used starting material in ruthenium chemistry.

α-Pinene Chemical compound

α-Pinene is an organic compound of the terpene class. It is one of the two isomers of pinene, the other being β-pinene. An alkene, it contains a reactive four-membered ring. It is found in the oils of many species of many coniferous trees, notably the pine. It is also found in the essential oil of rosemary and Satureja myrtifolia. Both enantiomers are known in nature; (1S,5S)- or (−)-α-pinene is more common in European pines, whereas the (1R,5R)- or (+)-α-isomer is more common in North America. The enantiomers' racemic mixture is present in some oils such as eucalyptus oil and orange peel oil.

In chemistry, transfer hydrogenation is a chemical reaction involving the addition of hydrogen to a compound from a source other than molecular H2. It is applied in laboratory and industrial organic synthesis to saturate organic compounds and reduce ketones to alcohols, and imines to amines. It avoids the need for high-pressure molecular H2 used in conventional hydrogenation. Transfer hydrogenation usually occurs at mild temperature and pressure conditions using organic or organometallic catalysts, many of which are chiral, allowing efficient asymmetric synthesis. It uses hydrogen donor compounds such as formic acid, isopropanol or dihydroanthracene, dehydrogenating them to CO2, acetone, or anthracene respectively. Often, the donor molecules also function as solvents for the reaction. A large scale application of transfer hydrogenation is coal liquefaction using "donor solvents" such as tetralin.

<span class="mw-page-title-main">Sandwich compound</span> Chemical compound made of two ring ligands bound to a metal

In organometallic chemistry, a sandwich compound is a chemical compound featuring a metal bound by haptic, covalent bonds to two arene (ring) ligands. The arenes have the formula CnHn, substituted derivatives and heterocyclic derivatives. Because the metal is usually situated between the two rings, it is said to be "sandwiched". A special class of sandwich complexes are the metallocenes.

<span class="mw-page-title-main">(Cymene)ruthenium dichloride dimer</span> Chemical compound

(Cymene)ruthenium dichloride dimer is the organometallic compound with the formula [(cymene)RuCl2]2. This red-coloured, diamagnetic solid is a reagent in organometallic chemistry and homogeneous catalysis. The complex is structurally similar to (benzene)ruthenium dichloride dimer.

<span class="mw-page-title-main">Organoruthenium chemistry</span>

Organoruthenium chemistry is the chemistry of organometallic compounds containing a carbon to ruthenium chemical bond. Several organoruthenium catalysts are of commercial interest and organoruthenium compounds have been considered for cancer therapy. The chemistry has some stoichiometric similarities with organoiron chemistry, as iron is directly above ruthenium in group 8 of the periodic table. The most important reagents for the introduction of ruthenium are ruthenium(III) chloride and triruthenium dodecacarbonyl.

<span class="mw-page-title-main">Dichlorotris(triphenylphosphine)ruthenium(II)</span> Chemical compound

Dichlorotris(triphenylphosphine)ruthenium(II) is a coordination complex of ruthenium. It is a chocolate brown solid that is soluble in organic solvents such as benzene. The compound is used as a precursor to other complexes including those used in homogeneous catalysis.

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

Hexamethylbenzene, also known as mellitene, is a hydrocarbon with the molecular formula C12H18 and the condensed structural formula C6(CH3)6. It is an aromatic compound and a derivative of benzene, where benzene's six hydrogen atoms have each been replaced by a methyl group. In 1929, Kathleen Lonsdale reported the crystal structure of hexamethylbenzene, demonstrating that the central ring is hexagonal and flat and thereby ending an ongoing debate about the physical parameters of the benzene system. This was a historically significant result, both for the field of X-ray crystallography and for understanding aromaticity.

<span class="mw-page-title-main">Half sandwich compound</span> Class of coordination compounds

Half sandwich compounds, also known as piano stool complexes, are organometallic complexes that feature a cyclic polyhapto ligand bound to an MLn center, where L is a unidentate ligand. Thousands of such complexes are known. Well-known examples include cyclobutadieneiron tricarbonyl and (C5H5)TiCl3. Commercially useful examples include (C5H5)Co(CO)2, which is used in the synthesis of substituted pyridines, and methylcyclopentadienyl manganese tricarbonyl, an antiknock agent in petrol.

Cymene describes organic compounds with the formula CH3C6H4CH(CH3)2. Three isomers exist: 1,2- 1,3-, and 1,4-. All are colorless liquids, immiscible in water, with similar boiling points. They are classified are aromatic hydrocarbons. The bearing two substituents: an isopropyl group and a methyl group.

<span class="mw-page-title-main">Organotantalum chemistry</span> Chemistry of compounds containing a carbon-to-tantalum bond

Organotantalum chemistry is the chemistry of chemical compounds containing a carbon-to-tantalum chemical bond. A wide variety of compound have been reported, initially with cyclopentadienyl and CO ligands. Oxidation states vary from Ta(V) to Ta(-I).

<span class="mw-page-title-main">(Benzene)ruthenium dichloride dimer</span> Chemical compound

(Benzene)ruthenium dichloride dimer is the organoruthenium compound with the formula [(C6H6)RuCl2]2. This red-coloured, diamagnetic solid is a reagent in organometallic chemistry and homogeneous catalysis.

Metal arene complexes are organometallic compounds of the formula (C6R6)xMLy. Common classes are of the type (C6R6)ML3 and (C6R6)2M. These compounds are reagents in inorganic and organic synthesis. The principles that describe arene complexes extend to related organic ligands such as many heterocycles (e.g. thiophene) and polycyclic aromatic compounds (e.g. naphthalene).

<i>o</i>-Cymene Organic compound

o-Cymene is an organic compound classified as an aromatic hydrocarbon. Its structure consists of a benzene ring ortho-substituted with a methyl group and an isopropyl group. It is a flammable colorless liquid which is nearly insoluble in water but soluble in organic solvents.

<i>m</i>-Cymene Organic compound

m-Cymene is an organic compound classified as an aromatic hydrocarbon. Its structure consists of a benzene ring meta-substituted with a methyl group and an isopropyl group. It is a flammable colorless liquid which is nearly insoluble in water but soluble in organic solvents.

RAPTA is a class of experimental cancer drugs. They consist of a central ruthenium(II) atom complexed to an arene group, chlorides, and 1,3,5-triaza-7-phosphaadamantane (PTA) forming an organoruthenium half-sandwich compound. Other related ruthenium anti-cancer drugs include NAMI-A, KP1019 and BOLD-100.

References

  1. Nomenclature of Organic Chemistry: IUPAC Recommendations and Preferred Names 2013 (Blue Book). Cambridge: The Royal Society of Chemistry. 2014. pp. 139, 597. doi:10.1039/9781849733069-FP001. ISBN   978-0-85404-182-4.
  2. Pabst, Florian; Blochowicz, Thomas (December 2022). "On the intensity of light scattered by molecular liquids - Comparison of experiment and quantum chemical calculations". The Journal of Chemical Physics . 157 (24): 244501. Bibcode:2022JChPh.157x4501P. doi: 10.1063/5.0133511 . PMID   36586992.
  3. Balahbib, Abdelaali; El Omari, Nasreddine; Hachlafi, Naoufal EL.; Lakhdar, Fatima; El Menyiy, Naoual; Salhi, Najoua; Mrabti, Hanae Naceiri; Bakrim, Saad; Zengin, Gokhan; Bouyahya, Abdelhakim (2021-07-01). "Health beneficial and pharmacological properties of p-cymene". Food and Chemical Toxicology. 153: 112259. doi:10.1016/j.fct.2021.112259. ISSN   0278-6915.
  4. Vora, Bipin V.; Kocal, Joseph A.; Barger, Paul T.; Schmidt, Robert J.; Johnson, James A. (2003). "Alkylation". Kirk‐Othmer Encyclopedia of Chemical Technology. doi:10.1002/0471238961.0112112508011313.a01.pub2. ISBN   0471238961.
  5. Bennett, M. A.; Huang, T.-N.; Matheson, T. W.; Smith, A. K. (1982). "(η6-Hexamethylbenzene)Ruthenium Complexes". Inorganic Syntheses . 21: 74–78. doi:10.1002/9780470132524.ch16. ISBN   9780470132524.