In which of the following reactions is the less substituted alkene (Hofmann product) the major one?

A2-bromo-2-methylbutane with $(CH X_{3}) X_{3} COK$ in $(CH X_{3}) X_{3} COH$
B2-bromobutane with $NaOEt$ in $EtOH$
Cbutan-2-yltrimethylammonium hydroxide, heated
D2-chloro-2-methylbutane with $NaOEt$ in $EtOH$

Answer: A, C

A bulky base (tert-butoxide) removes the more accessible terminal hydrogen, giving the Hofmann alkene, and so does the Hofmann elimination of a quaternary ammonium hydroxide (poor, bulky

N (CH X_{3}) X_{3}

leaving group). Ethoxide with a secondary bromide or with a tertiary chloride gives mainly the Saytzeff alkene.

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In which of the following reactions is the less substituted alkene (Hofmann product) the major one?

Answer: A, C

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