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Chapter 17 AROMATIC SUBSTITUTION REACTIONS 17.1 CH₃ + CH₃ : CH₃ -- CH₃ H H + H H NO₂ NO₂ NO₂ NO₂ + + The last structure is especially stable because the octet rule is satisfied at all atoms. 17.2 CH₃ CH₃ CH₃ :0 + + NO₂ NO₂ NO₂ H H + H No especially stable resonance structure is formed because the positive charge is never located on the carbon that is bonded to the methoxy group. + 17.3 a) The electron pair on the N can NH₂ NH₂ stabilize a positive charge on the + H H adjacent carbon by resonance. E E b) The ethyl group stabilizes a positive charge on the CH₂CH₃ adjacent carbon by hyperconjugation. + H E 247