question_answer

2-bromopentane is heated with potassium ethoxide in ethanol. The major product obtained is

A) pent-1-ene

B) 2-ethoxypentane

C) trores-pent-2-ene

D) cis-pent-2-ene

Correct Answer: C

Solution :

Secondary alkyl halides on treatment with alcoholic \[KOH\]preferably undergo elimination rather than substitution to give alkenes in accordance with Saytzeffrule. Usually the more stable (roras-alkenes predominate in this reaction. Thus, 2-bromopentane on heating potassium ethoxide in ethanol gives (raras-pent-2-ene.