Question

The reaction $ Ar{N_2}^ + C{l^ - }$ $\underrightarrow {Cu/HCl}\;$ $ArCl + {N_2} + CuCl $ is named as ____________.
A. Carbylamine reaction
B. Gatterman reaction
C. Claisen reaction
D. Sandmeyer reaction

Answer 1

Hint: In a Carbylamine reaction, isocyanide is formed from primary amine, aromatic compounds associated with formyl group $ \left( { - CHO} \right) $ is formed in a Gatterman reaction, diketone group is formed in a Claisen reaction and aryl halide is formed from aryl diazonium salts in the Sandmeyer reaction.

Complete Step by step answer:
In the reaction, $ Ar{N_2}^ + C{l^ - }$ $\underrightarrow {Cu/HCl}\;$ $ArCl + {N_2} + CuCl $, Ar represents aromatic compounds.

Now, we’ll go according to the options:
- In option A, Carbylamine reaction is defined as the reaction in which an isocyanide(-CN- group) is synthesized by the reaction of a primary amine, chloroform $ \left( {CHC{l_3}} \right) $, base. Primary amines means when one of three hydrogen atoms in ammonia is replaced by an alkyl or aromatic group. This reaction is also known as Hofmann isocyanide synthesis.
- In option B, Gatterman reaction is defined as the chemical reaction in which aromatic compounds are formulated by a mixture of hydrogen cyanide $ \left( {HCN} \right) $ or hydrogen chloride $ \left( {HCl} \right) $ in the presence of a Lewis acid catalyst such as $ AlC{l_3} $.
- In option C, Claisen reaction is defined as the carbon-carbon bond formed reaction that occurs between two esters or one ester and another carbonyl compound in the presence of a strong base which results in the formation of diketone.
- In option D, Sandmeyer reaction is a chemical reaction which is used to synthesize aryl halides $ \left( {R - Cl} \right) $ from aryl diazonium $ \left( {R - {N_2}^ + C{l^ - }} \right) $ salts using copper salts as reagents or catalysts. This reaction provides transformations on benzene such as halogenations, cyanation, etc. R represents the aryl group.
Hence, the reaction given in the question is named as Sandmeyer reaction. The products formed in this reaction are aryl chloride $ \left( {ArCl} \right) $, nitrogen gas $ \left( {{N_2}} \right) $ and copper chloride $ \left( {CuCl} \right) $.

Therefore, option D is correct.

Note: Remember the definitions of all these reactions i.e., type of products formed, reactants used and types of catalysts or reagents used. In the given reaction, Cu acts as a reagent or catalyst. Both aryl and alkyl halides can be formed from Sandmeyer reaction.