alkyl halide

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alkyl halide

chemical compound

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June 18, 2026

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An alkyl halide is an organic compound containing at least one halogen (fluorine, chlorine, bromine, or iodine) bonded to a carbon atom. These compounds are classified as primary, secondary, or tertiary based on the substitution of the carbon atom bonded to the halogen.12

The halogen atom draws electrons, creating a polar covalent bond with a partial positive charge on the carbon and a partial negative charge on the halogen. This polarity influences their chemical behavior. Alkyl halides are important in organic chemistry because they can be easily converted into other types of compounds through reactions like nucleophilic substitution, elimination, and the formation of Grignard reagents. They are also used industrially as solvents, pesticides, and intermediates in the production of dyes, drugs, and polymers.132

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alcohol
Substitution to form alkyl halides
Alkyl halides are often synthesized from alcohols, in effect substituting a halogen atom for the hydroxyl group. Hydrochloric (HCl), hydrobromic (HBr), and hydroiodic (HI) acids are useful reagents for this substitution, giving their best yields with tertiary alcohols. Thionyl chloride (SOCl₂), phosphorus tribromide…
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Alkyl halides are often synthesized from alcohols, in effect substituting a halogen atom for the hydroxyl group. Hydrochloric (HCl), hydrobromic (HBr), and hydroiodic (HI) acids are useful reagents for this substitution, giving their best yields with tertiary alcohols. Thionyl chloride (SOCl₂), phosphorus tribromide…
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amine
Occurrence and sources of amines
The reaction of alkyl halides, R―X, where X is a halogen, or analogous reagents with ammonia (or amines) is useful with certain compounds. A mixture of mono-, di-, and trialkylated amines, and sometimes also the quaternary ammonium salt, often results:
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The reaction of alkyl halides, R―X, where X is a halogen, or analogous reagents with ammonia (or amines) is useful with certain compounds. A mixture of mono-, di-, and trialkylated amines, and sometimes also the quaternary ammonium salt, often results:
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carboxylic acid
Synthesis
…a carboxylic acid with an alkyl halide (RCOOM + R′Βr → RCOOR′, where M is a metal ion such as sodium or potassium) in the solvent hexamethylphosphoric triamide. Alternatively, a special process called phase-transfer catalysis, which involves a transfer of ions from an aqueous phase to an organic phase, can…
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…a carboxylic acid with an alkyl halide (RCOOM + R′Βr → RCOOR′, where M is a metal ion such as sodium or potassium) in the solvent hexamethylphosphoric triamide. Alternatively, a special process called phase-transfer catalysis, which involves a transfer of ions from an aqueous phase to an organic phase, can…
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organosulfur compound
Preparation
…procedures, including reaction of an alkyl halide (RX, where X is a halogen) with the sulfur reagent thiourea, (NH₂)₂C=S, or with thiocyanate salts; reaction of organomagnesium (RMgX) or organolithium (RLiX) compounds with elemental sulfur; or addition of hydrogen sulfide or thioacetic acid (CH₃C(O)SH) to alkenes (olefins). 1,2-Dithiols can be prepared…
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…procedures, including reaction of an alkyl halide (RX, where X is a halogen) with the sulfur reagent thiourea, (NH₂)₂C=S, or with thiocyanate salts; reaction of organomagnesium (RMgX) or organolithium (RLiX) compounds with elemental sulfur; or addition of hydrogen sulfide or thioacetic acid (CH₃C(O)SH) to alkenes (olefins). 1,2-Dithiols can be prepared…
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ether
Williamson ether synthesis
…alkoxide ion to attack an alkyl halide, substituting the alkoxy (―O―R) group for the halide. The alkyl halide must be unhindered (usually primary), or elimination will compete with the desired substitution.
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…alkoxide ion to attack an alkyl halide, substituting the alkoxy (―O―R) group for the halide. The alkyl halide must be unhindered (usually primary), or elimination will compete with the desired substitution.
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