Which acts as poison for Pd-charcoal in Lindlar’s catalyst

• A) BaSO₄
• B) Quinoline
• C) Both A and B
• D) None of the above

In the context of Lindlar's catalyst, which is used for the selective hydrogenation of alkynes to alkenes, certain substances can inhibit its activity. The correct answer to your question is:

Answer

C) Both A and B

Explanation

Both barium sulfate (BaSO₄) and quinoline act as poisons for palladium (Pd) on charcoal in Lindlar's catalyst. BaSO₄ serves to limit the surface area of palladium, while quinoline is a ligand that can bind to the metal, reducing its catalytic activity.

Key Points

• Barium sulfate helps control the reaction selectivity.
• Quinoline prevents over-hydrogenation by poisoning the catalyst.

Understanding these components is crucial for effectively using Lindlar's catalyst in organic synthesis.