Question

In the following reaction CH3-CH2-CH(Br)-CH3 alc.KOH heat- CH3-CH-CH CH3[A] + CH3-CH2-CH=CH2 [B]

(a) (A) is major product and (B) is minor product

(b) (A) is minor product and (B) is major procut

(c) Both (A) and (B) are major products

(d) Only (B) is formed and (A) is not formed​

Answer 1

Answer:

option a will be correct

Answer 2

Reaction of 2-Bromo butane with alcoholic KOH.

Explanation:

• Reaction of 2-Bromo butane reacts is treated with alcoholic KOH then But-1-ene(B) and But-2-ene(A) is formed.
• But-1-ene is formed as major product.
• It is a dehydrohalogenation reaction of alkyl halide and major product will be least substituted alkene.
• In this reaction transition state is formed which consist of two types of carbanion.
• First type of carbanion is primary carbanion like transition state is formed which leads to But-1-ene which is more stable.
• Second type of carbanion is secondary carbanion like transition state is formed leading to But-2-ene which is not much stable.

So, Option(b) is correct i.e. (A) is a minor product and (B) is a major product.