Question

In the following sequence of reactions
\[C{H_3} - Br\xrightarrow{{KCN}}A\xrightarrow{{{H_3}{O^ + }}}B\xrightarrow[{LiAl{H_4}}]{{ETHER}}C\]
The end product C is
A.Acetone
B.Methane
C.Acetaldehyde
D.Ethyl alcohol

Answer 1

Hint: The products so obtained can be further represented through the equation:
\[C{H_3}Br\xrightarrow{{KCN}}C{H_3} - CN\xrightarrow{{{H_3}{O^ + }}}C{H_3} - COOH\xrightarrow{{LiAl{H_4}}}C{H_3} - C{H_2} - OH\]

Complete step by step answer:
 Firstly as we can see that we are given with the haloalkane so as we know that haloalkanes are the alkanes which are found to contain the halogen instead of the hydrogen in the alkanes. Here we are given the methyl bromide that is reacted with the \[KCN\] to form acetonitrile. Here we can say that the \[Br\] atom is replaced by the \[CN\] group.Further the hydrolysis process is carried out.here we must know about this process so it iis process in which the chemical compound breaks down due to the reaction with the water. When this process is carried out at that time the cyano group gives the carboxylic group. Then it is given that the product so obtained is further carried out with the process of reduction using the reagents like ether and lithium aluminium as reagent and finally gives the hydroxyl group. The products so obtained can be further represented through the equation:
\[C{H_3}Br\xrightarrow{{KCN}}C{H_3} - CN\xrightarrow{{{H_3}{O^ + }}}C{H_3} - COOH\xrightarrow{{LiAl{H_4}}}C{H_3} - C{H_2} - OH\]
The end product C is ethyl alcohol.
From this equation each and every reaction becomes more clear.From this we conclude that the correct answer for the above given question is option D.
Therefore, option (D) is correct.

Note:
Here we must note that some haloalkanes are useful themselves but many are valuable intermediates in the production of the other molecules.