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CH₃ OCH₃ CH₃ CH₃ OCCH₃ g) h) + CH₃ C CH₃ OCH₃ major product H₃C Cl + i) j) NH₃ I HS first step second step C H k) 1) Ph CH₃ O Cl CH₃ m) CH₃CH₂CH₂CH₂I 8.28 a) The substrates are tertiary, so they follow the SN1 mechanism. The right reaction is faster because bromide ion is a better leaving group than chloride ion. b) The substrates are primary, so they follow the SN2 mechanism. The left reaction is faster because the nucleophile is more reactive in an aprotic solvent. c) The leaving group is on a secondary carbon and the benzene ring can provide resonance stabilization of the carbocation. With a weak nucleophile and a polar solvent, the SN1 mechanism is favored. The right reaction is faster because the methyl group provides added stability to the resonance stabilized cation. d) Primary substrates follow the SN2 mechanism. The right reaction is faster because it has less steric hindrance at the electrophilic carbon. e) Secondary substrates with a weak nucleophile and a polar solvent favor the SN1 mechanism. The left reaction is faster because the carbocation is resonance stabilized. 119