QuestionOrganic / E2 elimination
Which one of the following bromides CANNOT form an alkene by E2 process?
- (a) 1-Bromo-2,2-dimethylpropane
- (b) 2-Bromo-2-methylbutane
- (c) 2-Bromo-3-methylbutane
- (d) 1-Bromo-3-methylbutane
Answer: (a) 1-Bromo-2,2-dimethylpropane
E2 needs a β-hydrogen. 1-Bromo-2,2-dimethylpropane (neopentyl bromide, (CH₃)₃C–CH₂Br): the β-carbon is quaternary, no β-H → cannot form an alkene by E2 → (a).