Question

By which reaction Freon-12 is manufactured from tetrachloromethane?

• A. Finkelstein reaction
• B. Grignard reaction
• C. Stephen reaction
• D. Swarts reaction

Hint:

Swarts reaction is specifically used to prepare alkyl fluorides from alkyl chlorides or bromides using metal fluorides. It is commonly used in the preparation of refrigerants like Freon.

Answer 1

The Correct Option is D

Step 1: Identify the compound and process.
Freon-12 (dichlorodifluoromethane, \( \text{CCl}_2\text{F}_2 \)) is prepared from tetrachloromethane (\( \text{CCl}_4 \)) by replacing chlorine atoms with fluorine atoms. This type of reaction involves halogen exchange. Step 2: Understand the Swarts reaction.
The Swarts reaction is specifically used for the preparation of alkyl fluorides from alkyl chlorides or bromides using metallic fluorides such as \( \text{SbF}_3 \), \( \text{AgF} \), or \( \text{Hg}_2\text{F}_2 \). This reaction replaces chlorine atoms with fluorine atoms. Step 3: Analyze the options.

• (A) Finkelstein reaction: Incorrect. It is used for halogen exchange (Cl/Br to I) using sodium iodide in acetone.
• (B) Grignard reaction: Incorrect. It involves formation of organomagnesium compounds.
• (C) Stephen reaction: Incorrect. It is used for reduction of nitriles to aldehydes.
• (D) Swarts reaction: Correct. It replaces chlorine atoms with fluorine atoms to form Freon-12.

Step 4: Conclusion.
Since Freon-12 is obtained by replacing chlorine atoms in tetrachloromethane with fluorine atoms, the reaction involved is the Swarts reaction.
Final Answer:Swarts reaction.