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Halohydrin Formation

Halohydrin Formation (Addition.) Converts CC=CC to CC(O)C(Br)C using Br₂/H₂O (or Cl₂/H₂O). Stereochemistry: Anti addition.

Addition

Reaction details

Name

Halohydrin Formation

Type

Addition

Starting Material

CC=CC

Product

CC(O)C(Br)C

Reagents
  • Br₂/H₂O (or Cl₂/H₂O)

Mechanism
  1. Smiles

    CC=CC

    Description

    2-Butene

  2. Smiles

    CC1C(C)Br1

    Description

    Bromonium ion forms

  3. Smiles

    CC(O)C(Br)C

    Description

    Water (nucleophile) opens ring at more substituted carbon

Stereochemistry

Anti addition

Regiochemistry

OH on more substituted carbon (Markovnikov-like)

Tips
  1. Water is nucleophile, not halide

  2. Product can be converted to epoxide with base

  3. Mechanism shown for Br₂; Cl₂ works analogously

Related Reactions
  • halogenation-alkene

  • epoxidation

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