Friedel-Crafts reaction

chemistry

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June 26, 2026

Quick Summary

The Friedel-Crafts reaction is a synthetic process in organic chemistry that typically uses anhydrous aluminum chloride as a catalyst. This reaction is used to synthesize hydrocarbons or ketones.1

There are two main types:
* Alkylation: An aromatic hydrocarbon reacts with an alkyl halide to form a hydrocarbon.1
* Acylation: An aromatic hydrocarbon reacts with an acyl chloride or acid anhydride to form a ketone.1

This reaction was discovered in 1877 by French chemist Charles Friedel and American chemist James M. Crafts. Acyl chlorides, a type of carboxylic acid derivative, are particularly reactive and can be used in Friedel-Crafts acylation to produce ketones.23

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aluminum
Compounds
…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 as a topical antiperspirant or body deodorant, which acts by constricting…
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…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 as a topical antiperspirant or body deodorant, which acts by constricting…
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carbonium ion
Reactions.
…benzene using isopropyl chloride (Friedel–Crafts reaction). Benzene acts as the donor molecule, with the donated electrons coming from the pi-bonded system of the benzene ring:
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…benzene using isopropyl chloride (Friedel–Crafts reaction). Benzene acts as the donor molecule, with the donated electrons coming from the pi-bonded system of the benzene ring:
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hydrocarbon
Reactions
…(AlCl₃) are referred to as Friedel-Crafts reactions after French chemist and mineralogist Charles Friedel and American chemist James M. Crafts, who discovered this reaction at the Sorbonne in 1877. Further substitution is possible, and under certain circumstances all six hydrogen atoms of benzene are capable of being replaced. The products…
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…(AlCl₃) are referred to as Friedel-Crafts reactions after French chemist and mineralogist Charles Friedel and American chemist James M. Crafts, who discovered this reaction at the Sorbonne in 1877. Further substitution is possible, and under certain circumstances all six hydrogen atoms of benzene are capable of being replaced. The products…
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