aluminum chloride

chemical compound

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June 18, 2026

Quick Summary

Aluminum chloride (AlCl₃) is a chemical compound that exists as yellowish-white to colorless crystals or powder. It is a deliquescent hydrate, meaning it absorbs moisture from the air.1

Aluminum chloride has various applications, including in salting out glycerin lyes in soapmaking, carbonizing wool, and as a disinfectant, deodorant, and astringent. It is also commonly used as a catalyst in Friedel-Crafts reactions, which are synthetic organic reactions used in preparing a wide range of compounds. Hydrated aluminum chloride, known as aluminum chlorohydrate, is used in antiperspirants.12

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aluminum
Compounds
… with molten aluminum metal produces aluminum chloride; the latter is the most commonly used catalyst in Friedel-Crafts reactions—i.e., synthetic organic reactions involved in the preparations of a wide variety of compounds, including aromatic ketones and anthroquinone and its derivatives. Hydrated aluminum chloride, commonly known as aluminum chlorohydrate, AlCl₃∙H₂O, is used…
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… with molten aluminum metal produces aluminum chloride; the latter is the most commonly used catalyst in Friedel-Crafts reactions—i.e., synthetic organic reactions involved in the preparations of a wide variety of compounds, including aromatic ketones and anthroquinone and its derivatives. Hydrated aluminum chloride, commonly known as aluminum chlorohydrate, AlCl₃∙H₂O, is used…
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hydrocarbon
Chemical reactions
known as isomerization employs an aluminum chloride (AlCl₃) catalyst to convert unbranched alkanes to their branched-chain isomers. In one such application, butane is isomerized to 2-methylpropane for use as a starting material in the preparation of 2,2,4-trimethylpentane (isooctane), which is a component of high-octane gasoline.
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known as isomerization employs an aluminum chloride (AlCl₃) catalyst to convert unbranched alkanes to their branched-chain isomers. In one such application, butane is isomerized to 2-methylpropane for use as a starting material in the preparation of 2,2,4-trimethylpentane (isooctane), which is a component of high-octane gasoline.
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acid–base reaction
Aldol condensation, base-catalyzed
…such as boron trifluoride (BF₃), aluminum chloride (AlCl₃), and titanium tetrachloride (TiCl₄), is believed to be caused by their interaction with proton acids (for example, traces of water) and the olefin to give a carbonium ion, which then reacts further with more olefin:
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…such as boron trifluoride (BF₃), aluminum chloride (AlCl₃), and titanium tetrachloride (TiCl₄), is believed to be caused by their interaction with proton acids (for example, traces of water) and the olefin to give a carbonium ion, which then reacts further with more olefin:
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