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| title | chunk | source | category | tags | date_saved | instance |
|---|---|---|---|---|---|---|
| Alkylation | 2/2 | https://en.wikipedia.org/wiki/Alkylation | reference | science, encyclopedia | 2026-05-05T10:45:52.443136+00:00 | kb-cron |
C
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CH
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{\displaystyle {\ce {C2H4 + CH3CO2H -> CH3CO2C2H5}}}
== In biology ==
Alkylation in biology causes DNA damage. It is the transfer of alkyl groups to the nitrogenous bases. It is caused by alkylating agents such as EMS (Ethyl methanesulfonate). Bifunctional alkyl groups which have two alkyl groups in them cause cross linking in DNA. Alkylation damaged ring nitrogen bases are repaired via the base excision repair (BER) pathway.
== Commodity chemicals == Several commodity chemicals are produced by alkylation. Included are several fundamental benzene-based feedstocks such as ethylbenzene (precursor to styrene), cumene (precursor to phenol and acetone), linear alkylbenzene sulfonates (for detergents).
== Gasoline production ==
In a conventional oil refinery, isobutane is alkylated with low-molecular-weight alkenes (primarily a mixture of propene and butene) in the presence of a Brønsted acid catalyst, which can include solid acids (zeolites). The catalyst protonates the alkenes (propene, butene) to produce carbocations, which alkylate isobutane. The product, called "alkylate", is composed of a mixture of high-octane, branched-chain paraffinic hydrocarbons (mostly isoheptane and isooctane). Alkylate is a premium gasoline blending stock because it has exceptional antiknock properties and is clean burning. Alkylate is also a key component of avgas. By combining fluid catalytic cracking, polymerization, and alkylation, refineries can obtain a gasoline yield of 70 percent. The widespread use of sulfuric acid and hydrofluoric acid in refineries poses significant environmental risks. Ionic liquids are used in place of the older generation of strong Bronsted acids.
== Dealkylation == Complementing alkylation reactions are the reverse, dealkylations. Prevalent are demethylations, which are prevalent in biology, organic synthesis, and other areas, especially for methyl ethers and methyl amines.
== See also == Hydrodealkylation Transalkylation Alkynylation Friedel–Crafts reaction Category:Alkylating agents Category:Ethylating agents Category:Methylating agents
== References ==
== External links == Macrogalleria page on polycarbonate production Alkylating+agents at the U.S. National Library of Medicine Medical Subject Headings (MeSH)