Cyclopentane is converted into Ctclopentyl Cyanaide in following two steps,
Step 1:
Cyclopentane is reacted with Chlorine in the presence of sunlight. A Free Radical Substitution Reaction results in the formation of Chlorocyclopentane.
Step 2:
In second step, Chlorocyclopentane is reacted with Potassium Cyanide which undergoes Nucleophilic Substitution Reaction resulting in the formation of Cyclopentyl Cyanide as shown below,