The given reaction \(\mathrm{C}_{6} \mathrm{H}_{5}-\stackrel{\oplus}{\mathrm{N}} \equiv \mathrm{NCl}^{\ominus} \xrightarrow{\mathrm{Cu}_{2} \mathrm{Cl}_{2} / \mathrm{HCl}} \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{Cl}+\mathrm{N}_{2}\) is known as

Concept:

• Glaser Reaction:

  • The Glaser reaction is a coupling reaction used to form a conjugated di-yne from two terminal alkynes, facilitated by a copper(I) catalyst:

  • \(2 \text{RC}≡\text{CH} \xrightarrow{\text{O}_2, \text{CuCl, Py}} \text{RC}≡\text{C}−\text{C}≡\text{CR}\)

• Schiemann Reaction:

  • The Schiemann reaction is a method to prepare aryl fluorides from aryl diazonium salts. A diazonium salt reacts with fluoroboric acid (HBF₄) and is then thermally decomposed to produce an aryl fluoride:

  • ​\(\text{C}_6\text{H}_5−\text{N}_2^+\text{BF}_4^- \xrightarrow{Δ} \text{C}_6\text{H}_5\text{F} + \text{BF}_3 + \text{N}_2 \)

• Sandmeyer Reaction:

  • The Sandmeyer reaction involves the synthesis of aryl halides from aryl diazonium salts using copper(I) chloride (Cu₂Cl₂) or copper(I) bromide (Cu₂Br₂) in the presence of hydrochloric or hydrobromic acid:

  • \( \text{C}_6\text{H}_5−\text{N}_2^+\text{Cl}^- \xrightarrow[\text{Cu}_2\text{Cl}_2]{\text{HCl}} \text{C}_6\text{H}_5\text{Cl} + \text{N}_2\)

• Chlorination:

  • Chlorination is a broad term that refers to any chemical reaction involving the introduction of chlorine atoms into a molecule, either through addition, substitution, or oxidation processes.