Question

Reaction of t-butyl bromide with sodium methoxide produces.

• A. Isobutane
• B. Isobutylene
• C. Sodium t-butoxide
• D. t-butyl methyl ether

Answer 1

Answer: (B)

Isobutylene

Answer 2

$CH_{3} - \overset{\underset{CH_{3}}{CH_{3}}}{\overset{\underset{|}{|}}{C -}} ⥂ Br + CH_{3}ONa\overset{\quad\text{Elimination}\quad}{\rightarrow}$

$\underset{\text{Isobutylene}}{CH_{3} - \overset{CH_{3}}{\overset{|}{C =}} ⥂ CH_{2}} + CH_{3}OH + NaBr$

$CH_{3}ONa \rightarrow CH_{3}O^{-} + Na^{+}$

methoxide ion $(CH_{3}O^{-})$ is a strong base, therefore it abstract proton from $3^{o}$alkyl halide and favours elimination reaction.