Question

Identify $A$ and $B$ and rewrite the reaction $[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}{{I}^{-}}]\xrightarrow[{{H}_{2}}O]{A{{g}_{2}}O}A\xrightarrow{\Delta }B+{{(C{{H}_{3}})}_{3}}N+{{H}_{2}}O$ What is the action of benzene diazonium Chloride on phenol in alkaline medium?

Answer 1

Hint: In the given question it is asked about the product that would form at the reaction of Benzene diazonium chloride and phenol. Now as the medium is basic then it indicates that the product that will form would be of the nature of ortho-substituted and acid reduced which gives us the right option and the final-product as the P-hydroxy azobenzene.

Complete step by step answer:
In the question it is given that phenol is prepared from benzene diazonium chloride. We must find which type of reaction benzene diazonium chloride undergoes to form phenol. - Benzene diazonium chloride on heating in presence of aqueous solution gives phenol as a main product and nitrogen gas a by-product.
Benzene diazonium chloride is hydrolysed to phenols by treating it with dilute acids. Therefore, the preparation of phenol from benzene diazonium chloride involves hydrolysis reaction.
And the A and B from the given reaction is given by,
$[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}{{I}^{-}}]\xrightarrow[{{H}_{2}}O]{A{{g}_{2}}O}[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}O{{H}^{-}}]+AgCl$
Thus, compound A is $[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}O{{H}^{-}}]$ i.e. ethyltrimethyl ammonium hydroxide.
$[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}O{{H}^{-}}]\xrightarrow{\Delta }{{C}_{2}}H={{C}_{2}}H+{{(C{{H}_{3}})}_{3}}N+{{H}_{2}}O$ and compound B is ${{C}_{2}}H={{C}_{2}}H$ i.e. Ethylene.
Therefore, product A and B is $[{{C}_{2}}{{H}_{5}}{{N}^{+}}{{(C{{H}_{3}})}_{3}}O{{H}^{-}}]$ and ${{C}_{2}}H={{C}_{2}}H$ respectively.

Additional Information:
Benzene diazonium chloride is ionic in nature (contains positive charge on nitrogen and a negative charge on chlorine).
Benzene diazonium chloride is water-soluble.
Benzene diazonium chloride is colourless and crystalline solid.
Benzene diazonium chloride is soluble in water and reacts only when it is heated.

Note: Benzenediazonium chloride is an organic compound. It is a salt of a diazonium cation and chloride. It exists as a colourless solid that is soluble in polar solvents including water. It is the parent member of the aryl diazonium compounds, which are widely used in organic chemistry.