Give a brief account of the following reaction. (i) esterification, (ii) Riemer Tiemann reaction.

Explanation

When an alkyl halide is heated with an alcoholic solution of sodium alkoxide, the corresponding ethers are obtained. The reaction involves `SN^(2)` mechanism.
`CH_(3)-Ona + Br - C_(2)H_(5) overset(Delta) to CH_(3) - O -C_(2)H_(5) + NaBr`
Mechanism:
`CH_(3) -O^(-)Na^(+) + CH_(3) - CH_(2)-Br overset(-NaBr) underset(Delta) to underset("methoxyethane")(CH_(3)-CH_(2)-overset(..)underset(..)O -CH_(3)`
Primary allkyl halides are more susceptible for `SN^(2)` reaction. Hence for the preparation of mixed ether having primary and tertiary alkyl group, primary alkyl halide and tertiary alkoxide are used. On the other hand, if we use tertiary alkyl halide and primary alkoxide are used. On the other hand, if we use tertiary alkyl halide and primary alkoxide, elimination domiantes and succedes over substitution to form an an alkene.