Inductive effect, electromeric effect, resonance, hyperconjugation
- A tertiary butyl carbocation is more stable than a secondary butyl carbocation because of which of the following ? Answer: 4. Hyperconjugation Methyl groups attached to the positive carbon stabilise it by hyperconjugation: C-H sigma electrons delocalise i... 1
- Which of the following is correct with respect to -I effect of the substituents ? (R = alkyl) Answer: 3. - NR ₂ < - OR < - F The -I effect increases with the electronegativity of the atom attached to the carbon chain: N < O < F. Since... 1
- In pyrrole [figure: five-membered ring, N1 with H, carbons 2,3,4,5] the electron density is maximum on Answer: 3. 2 and 5 Key idea: in pyrrole the N lone pair is part of the aromatic sextet, so the ring carbons are electron-rich, most of all t... 1