UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper III
Q6(b). Stability of primary carbocations
Question
Order I CH₃CH₂⁺, II CH₃CH₂CH₂⁺, III CH₃OCH₂⁺ and IV CH₃OCH₂CH₂⁺ by decreasing stability.
Answer in brief
The conventional open-ion comparison is III > I > II > IV.
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CoversStability of primary carbocationsElectronic effects
All parts of Question 6
- 6(a) Ozonolysis of an exocyclic alkene4 marks
- 6(b) Stability of primary carbocations4 marks
- 6(c) Dehydration of pentan-2-ol4 marks
- 6(d) Peroxide effect4 marks
- 6(e) Fused cyclobutene opening4 marks
- 6(f) Benzyne substitution of p-iodotoluene4 marks
- 6(g) Inductive ether fragmentation4 marks
- 6(h) Schmidt reaction of cinnamic acid4 marks
- 6(i) Heterocycle aromaticity4 marks
- 6(j) Cyanohydrin acyl-anion equivalent4 marks