UPSC Combined Geo-Scientist, Mains · 2017 · Mains Paper III
Q6(e). Steric inhibition of resonance
Question
Explain the enhanced basicity of the depicted 2,6-di-tert-butylaniline relative to aniline.
Answer in brief
Bulky ortho groups twist the amino group away from effective conjugation, making its lone pair more available for protonation.
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CoversSteric inhibition of resonanceAmine basicity
All parts of Question 6
- 6(a) Nitrophenol acidity5 marks
- 6(b) Benzene and cyclooctatetraene orbitals5 marks
- 6(c) Aldehyde electrophilicity5 marks
- 6(d) Carbocation stability5 marks
- 6(e) Steric inhibition of resonance5 marks
- 6(f) Cyclopropenone dipole5 marks
- 6(g) SN1 and aromatic cations5 marks
- 6(h) Exhaustive methylation of piperidine5 marks