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Williamson synthesis

Explanation

Williamson ether synthesis
This is one of the best method for the preparation symmetrical and unsymmetrical ethers. In this method, sodium or potassium alkoxide is heated with an alkyl halide to form an ether.
`C_(2)H_(5)-X+C_(2)H_(5)overset(-)Ooverset(+)NararrC_(2)H_(5)OC_(2)H_(5)+NaX[X=Br,Cl]`
Mechanism
It involves nucleophilic attack of alkoxide ion on alkyl halide according to `S_(N)2` mechanism.
`undersetunderset("(alkoxide ion)")("Nucleophile")(H_(3)C-O^(-))+undersetunderset(("alkyl halide"))("Substrate")(CH_(3)-X)overset("Slow")rarr[CH_(3)-overset(delta-)O-CH_(3)....overset(delta-)(X)]CH_(3)-underset("Ether")overset(darr"Fast")O-CH_(3)+X^(-)`