Explain the ammonolysis of alkyl halide compounds.

(N/A) The carbon-halogen bond in alkyl or benzyl halides can be easily cleaved by a nucleophile. Hence,an alkyl or benzyl halide on reaction with an ethanolic solution of ammonia undergoes a nucleophilic substitution reaction in which the halogen atom is replaced by an amino $(-NH_{2})$ group. This process of cleavage of the $C-X$ bond by an ammonia molecule is known as ammonolysis.
The reaction is carried out in a sealed tube at $373 \ K$. The primary amine thus obtained behaves as a nucleophile and can further react with alkyl halide to form secondary and tertiary amines,and finally a quaternary ammonium salt.
The free amine can be obtained from the ammonium salt by treatment with a strong base: $R-NH_{3}^{+}X^{-} + NaOH \rightarrow R-NH_{2} + H_{2}O + Na^{+}X^{-}$.
Ammonolysis has the disadvantage of yielding a mixture of primary,secondary,and tertiary amines and also a quaternary ammonium salt.
However,a primary amine is obtained as a major product by taking a large excess of ammonia.
The order of reactivity of halides with amines is $R-I > R-Br > R-Cl$.