meta-Cresol, also 3-methylphenol, is an organic compound with the formula CH3C6H4(OH). It is a colourless, viscous liquid that is used as an intermediate in the production of other chemicals. It is a derivative of phenol and is an isomer of p-cresol and o-cresol.[3]
Together with many other compounds, m-cresol is traditionally extracted from coal tar, the volatile materials obtained in the production of coke from (bituminous) coal. This residue contains a few percent by weight of phenol and isomeric cresols. In the cymene-cresol process, toluene is alkylated with propylene to give isomers of cymene, which can be oxidatively dealkylated analogous to the cumene process. Another method, involves carbonylation of a mixture of methallyl chloride and acetylene in the presence of nickel carbonyl.[3]
m-Cresol is a precursor to numerous compounds. Important applications include:
- pesticides such as fenitrothion and fenthion
- synthetic vitamin E by methylation to give 2,3,6-trimethylphenol[3]
- antiseptics, such as amylmetacresol
- a solvent for polymers. For example, polyaniline is cast from a solution of m-cresol to form a polyaniline film with a superior conductivity than polyaniline alone. This phenomenon is known as secondary doping.[4]
- preservatives in some insulin preparations
- the starting point in the total synthesis of thymol,[5] an important synthetic chemical for regions lacking natural sources of the flavor compound:[6]
- synthesis of dicresulene and policresulen[citation needed]
- synthesis of toliprolol, tolamolol & cresatin[citation needed]
m-Cresol is a component found in temporal glands secretions during musth in male African elephants (Loxodonta africana).[7]
m-Cresol is a constituent of tobacco smoke.[8]
m-Cresol is a component found in secretions from the ant Colobopsis saundersi during Autothysis.[9][10]
- Cresol
- NIOSH Pocket Guide to Chemical Hazards cdc.gov
- Chemical and physical properties chemicalbook.com
