JEE Main levelSingle correct optionDifficulty 2 of 3g3015
The major product of the reaction of 3,3-dimethylbut-1-ene with HCl (carbocation intermediate allowed to rearrange) is:
A2-chloro-3,3-dimethylbutane
B3-chloro-2,2-dimethylbutane
C1-chloro-3,3-dimethylbutane
D2-chloro-2,3-dimethylbutane
Answer: D
Proton addition gives the secondary 3,3-dimethylbutan-2-yl cation. A 1,2-methyl shift gives the tertiary 2,3-dimethylbutan-2-yl cation, which is captured by chloride to give 2-chloro-2,3-dimethylbutane.