Question

Give the major product obtained from the reaction of each of the following with excess HCI:

a.CH₃CH₂C≡CH

b.CH₃CH₂C≡CCH₂CH₃

c.CH₃CH₂C≡CCH₂CH₂CH₃

Short answer

a)

b)

c)

Step-by-step solution

How will reaction proceed

Excess HCl is used which do markoniv addition and replaces triple bond to single bond by chlorine.

In unsymmetrical alkynes two products will form as Cl can attached with any triple bonded carbon atom but not with terminal carbon atom.

Final answer

a) Excess HCl is used which do markoniv addition and replaces triple bond to single bond by chlorine.

b) In symmetrical alkyne in excess HCl Cl can attach with any carbon atom as product will be same.

c) In unsymmetrical alkynes two products will form as Cl can attached with any triple bonded carbon atom but not with terminal carbon atom.