vicinal dihalide

chemical compound

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July 14, 2026

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A vicinal dihalide is an organic compound containing two halogen atoms bonded to adjacent carbon atoms. These compounds are a type of organohalogen, which are organic molecules with at least one halogen atom (fluorine, chlorine, bromine, or iodine) attached to carbon.123

Vicinal dihalides can be prepared by treating geminal dihalides (where both halogens are on the same carbon) or vicinal dihalides with a base. This process can yield vinylic halides, which have halogens attached to carbons involved in a double bond. A common example is 1,2-dichloroethane, which can be used to produce vinyl chloride, a key component in the production of polyvinyl chloride (PVC).24

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organohalogen compound
Synthesis
Vicinal dihalides, compounds that have halogens on adjacent carbons, are prepared by the reaction between a halogen and an alkene. The simplest example is the reaction between ethylene and chlorine to give 1,2-dichloroethane (ethylene dichloride). 1,2-Dichloroethane leads all other organohalogen compounds in terms of its…
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Vicinal dihalides, compounds that have halogens on adjacent carbons, are prepared by the reaction between a halogen and an alkene. The simplest example is the reaction between ethylene and chlorine to give 1,2-dichloroethane (ethylene dichloride). 1,2-Dichloroethane leads all other organohalogen compounds in terms of its…
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organohalogen compound
Dehydrohalogenation of a dihalide
…the same carbon) or a vicinal dihalide (halogens on adjacent carbons) with a base such as sodium ethoxide (NaOCH₂CH₃) yields a vinylic halide.
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…the same carbon) or a vicinal dihalide (halogens on adjacent carbons) with a base such as sodium ethoxide (NaOCH₂CH₃) yields a vinylic halide.
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