UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper III
Q6(i). Heterocycle aromaticity
Question
Classify the depicted I pyrimidine, II oxazole, III 1H-azepine and IV glutarimide as aromatic, antiaromatic or nonaromatic.
Answer in brief
I and II are aromatic; equilibrium III and IV are nonaromatic.
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CoversHeterocycle aromaticityAromaticity
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