Identify the compound which gives an optically active haloalkane on reaction with H ₂ / Ni on heating.

Step-by-step solution

H₂ /Ni reduces the double bond to give a haloalkane. The product is optically active only if it contains a chiral centre (4 different groups on the Cl-bearing carbon). A (3-chloropent-1-ene): Reduction gives 3-chloropentane. Cl-bearing carbon has two identical -CH₂CH₃ groups. Achiral — optically inactive. B (4-chloropent-2-ene): Reduction gives 2-chloropentane. Cl-bearing carbon has -H , -Cl , -CH₃ , and -CH₂CH₂CH₃ — four different groups. Chiral centre — optically active. C (3-chloro-2,4-dimethylpent-1-ene): Reduc