Illustrate with example the limitations of Williamson synthesis for the prepartion of certain types of ethers

Explanation

If the alkyl halide is tertiary then the major product is an alkene and alkoxide then acts as a strong base not as a nucelophile
figure
Chlorobenzene does not give Williamson synthsis due to partial double bond character of C-Cl bond.So, aromatic ethers are prepared from sodium phenoxide
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