Question

Acetonitrile on reduction gives:
A. ethanamine
B. propanamine
C. methenamine
D. None of the above

Answer 1

Acetonitrile is the simplest organic nitrile. It plays the role of polar aprotic solvent. Acetonitrile is aliphatic in nature and it is a volatile compound. For acetonitrile to be reduced, hydrogens should be added in order to carry out the reaction.

Complete step-by-step answer:
Acetonitrile, also known as ethanenitrile, is given by the formula $C{H_3} - CN$. The reduction of acetonitrile takes place as follows,
$C{H_3} - CN + 4\left[ H \right]\xrightarrow{{reduction}}C{H_3} - C{H_2} - N{H_2}$
acetonitrile ethanamine
The reduction can be done by using $LiAl{H_4}$ that is lithium aluminium hydride and $Na$ in ${C_2}{H_5}OH$.
Lithium aluminium hydride, $LiAl{H_4}$, is grey solid. It is abbreviated to LAH. LAH is widely used in organic chemistry as a reducing agent. It reduces amides and nitriles to amines.
Sodium in ethyl alcohol that is $Na$ in ${C_2}{H_5}OH$ is also a strong reducing agent. It reduces $C{H_3} - CN$ to $C{H_3} - C{H_2} - N{H_2}$. This reaction is known as the Medius reaction.

Additional information:
Industrially, acetonitrile is used as a solvent for the manufacture of pharmaceuticals and photographic film.
Ethylamine is an organic compound and is a colourless gas and has a strong ammonia like odour. It is widely used in the chemical industry and organic synthesis.

Therefore, the correct option is (A) that is ethanamine.

Note: Reduction is a process in which hydrogens are added or electrons are gained by a compound. Reducing agent is a compound which donates electrons to the compound that has to be reduced and itself gets oxidized.
You can also solve this question by keeping in mind that acetonitrile is a two-carbon nitrile. Hence the reduced compound will also be a two-carbon amine that will be ethanamine.