Question

Nitroalkanes are obtained in laboratory from primary or secondary alkyl halides by the action of:
A.$AgN{O_2}$
B.$NaN{O_3}$
C.$AgN{O_3}$
D.$HN{O_3}$

Answer 1

To answer this question, you should recall the concept of nitro compounds. The organic compounds that have one or more groups that are nitro functional $( - N{O_2})$ are called nitro compounds. Simply put, any group of chemical compounds that has the nitro group $\left( { - O - N = O} \right)$ becoming a member of the structure of molecules is a nitro compound.

Complete answer:
The reaction named nitration by the mixing of an organic compound and nitric acid helps in the formation of the nitro compound. Toluene or benzene which are the aromatic compounds in nitration is affected usually when they are treated with the mix of sulphuric and nitric acids. The amine is produced by reduction mostly owing to the acidic conditions. Hydroxylamine is produced by reduction when the conditions are neutral. Nitrogen to nitrogen bond compounds are formed in an alkaline solution.
Nitroalkanes are obtained by the action of silver nitrite $AgN{O_2}$ ​ on alkyl halides as follow: $R - X + AgN{O_2} \to R - N{O_{2}} + AgX$.
Example of this reaction: ${C_2}{H_5} - I + AgN{O_2} \to {C_2}{H_{5}}N{O_2} + AgI$.

Hence, the correct option is option A.

Note:
Alkyl halides react with silver nitrite in ethanolic solution to give nitro compounds. Alkyl nitrite is formed in a minor quantity. This reaction is used to prepare ${1^o}$ nitro compounds primarily while ${2^o}$and${3^o}$ halides give the major proportion of alkenes due to $\beta$ elimination. Contrary to this alkali nitrites give alkyl nitrites as the major product. This is due to the ionic nature of alkali nitrite. But if the reaction is carried out in solvents like DMF or DMSO, then even $NaN{O_2}$ or$KN{O_2}$ give good yield (about 60%) of the nitro compound.