Question

In the given reaction;
\[C{H_3}\, - \,CN\,\xrightarrow{{Na/\,{C_2}{H_5}OH}}A\xrightarrow{{HN{O_2}}}\,B\,\xrightarrow{\begin{subarray}{l}
  Cu \\
  573k
\end{subarray} }\,C\,\]
identify C.

Answer 1

Hint:\[C{H_3}\, - \,CN\,\]- methyl cyanide and cyanides (this is a reduction reaction).
Ethylamine is a primary amine which acts as a base on reaction with an acid.

Complete step by step answer:
Here methyl cyanide is reduced by using sodium in alcohol which is a strong reducing agent and it converts nitrites into amines. In this particular case
consider the given below reaction;
\[C{H_3}\, - \,CN\,\xrightarrow{{Na/\,{C_2}{H_5}OH}}{C_2}{H_5}\, - \,N{H_2}\]
This reaction is also known as Mendius Reduction reaction.
The product obtained is Ethyl amine
A = Ethyl amine \[{C_2}{H_5}\, - \,N{H_2}\] (after reduction of methyl cyanide in the presence of strong reducing agent that is, sodium in alcohol)
Now A which is Ethyl amine reacts with \[HNO_{_2}^{}\](Nitrous acid) to form ethyl alcohol
consider the given below reaction;
\[{C_2}{H_5}\, - \,N{H_2}\xrightarrow{{HN{O_2}}}\,{C_2}{H_5}OH\]
When ethylamine reacts with nitrous acid, it forms diazonium salt which is unstable, liberating nitrogen gas and ethanol.
B = Ethyl alcohol
ethyl alcohol reacts with Cu at 573K to produce Ethanal or Acetaldehyde.
Consider the given below reaction;
\[{C_2}{H_5}OH\,\xrightarrow{\begin{subarray}{l}
  Cu \\
  573k
\end{subarray} }\,C{H_3}\, - \,CHO\]
When ethanol is treated with Cu at 573 kelvin, it gets oxidized into ethanol or acetaldehyde.
Now consider the whole reaction altogether to check your products in each step.
The complete reaction is as follows;
\[C{H_3}\, - \,CN\,\xrightarrow{{Na/\,{C_2}{H_5}OH}}{C_2}{H_5}\, - \,N{H_2}\xrightarrow{{HN{O_2}}}\,{C_2}{H_5}OH\,\xrightarrow{\begin{subarray}{l}
  Cu \\
  573k
\end{subarray} }\,C{H_3}\, - \,CHO\]
In the first step methyl cyanide reacts with Na + alcohol and gets reduced to ethyl amine and then this ethyl amine gets converted into ethanol or ethyl alcohol and then this ethyl alcohol reacts with Cu at 573 kelvin to produce acetaldehyde.

Note: Solve such questions in step by step manner. Start solving them from the very first step and keep identifying the products in each step to reach the final answer. Always keep in mind the reagents with which the substances are reacting and the kind of reaction that can take place in order to get an appropriate product.