Question

What are the starting materials to get $2$-methylpropene as the major product?

• A. Sodium methoxide and sec-butyl bromide
• B. Sodium ethoxide and sec-butyl bromide
• C. Sodium tert-butoxide and ethyl bromide
• D. Sodium methoxide and tert-butyl bromide

Answer 1

Answer: (D)

Sodium methoxide and tert-butyl bromide

Answer 2

Alkoxide ions are both powerful nucleophiles and bases. Thus, when they are treated with a tert alkyl halide, they bring its dehydrohalogenation resulting in the formation of alkene. Hence, the alkyl halide taken must be tertiary.