Octet

Octet / Reactions

Williamson Ether Synthesis

Williamson Ether Synthesis (Substitution.) Converts C[O-] to COC using R-X (alkyl halide), alkoxide.

Substitution

Reaction details

Name

Williamson Ether Synthesis

Type

Substitution

Starting Material

C[O-]

Product

COC

Reagents
  • R-X (alkyl halide)

  • alkoxide

Mechanism
  1. Smiles

    C[O-]

    Description

    Methoxide anion (from NaH + MeOH)

  2. Smiles

    CI

    Description

    Methyl iodide (1° halide works best)

  3. Smiles

    COC

    Description

    Dimethyl ether via SN2

Tips
  1. Best method for making ethers

  2. Use 1° or methyl halides (SN2 mechanism)

  3. Bulky alkoxide + 3° halide → elimination instead!

  4. Unsymmetrical ethers: put smaller group on halide

Related Reactions
  • sn2-bromide-hydroxide

This is one row of the Reaction roadmap sheet - print all 83 reactions on one page.