See image — GOC and Organic Chemistry Basics Chemistry Question

💡 Solution & Explanation

# Basicity Order Analysis **Step 1: Identify the nitrogen lone pair character in each compound** - **I: $(F_3C)_3N$** — Nitrogen lone pair is delocalized/withdrawn by three electron-withdrawing $CF_3$ groups → **very weak base** - **II: Pyridine** — Aromatic $sp^2$ nitrogen; lone pair in $p$-orbital, involved in aromaticity → **weak base** - **III: Quinuclidine** — Saturated $sp^3$ nitrogen; lone pair freely available, not delocalized → **strong base** - **IV: Pyrrole** — Nitrogen lone pair is delocalized into the aromatic ring to maintain aromaticity → **very weak base** **Step 2: Apply basicity principles** Basicity increases with: - Lone pair availability (saturated > aromatic) - Less delocalization/withdrawal - Higher $s$-character in lone pair orbital **Step 3: Rank basicity** $$\text{III (quinuclidine)} > \text{II (pyridine)} > \text{IV (pyrrole)} > \text{I (tris-CF}_3\text{)}$$ Quinuclidine is the strongest (isolated $sp^3$ lone pair), pyridine is moderate, pyrrole's lone pair is trapped in aromaticity, and $(F_3C)_3N$ is the weakest due to electron withdrawal. **Answer: (B) III > II > IV > I**