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JEE Main levelSingle correct optionDifficulty 2 of 3o2023

2-Methylbut-2-ene, $(CH X_{3}) X_{2} C = CH - CH X_{3}$ , reacts with HBr in the presence of peroxide. The major product is

A2-bromo-2-methylbutane
B1-bromo-2-methylbutane
C2-bromo-3-methylbutane
D1-bromo-3-methylbutane

Answer: C

Br \cdot

adds to the less hindered carbon (the CH carbon, C-3) so that the tertiary radical at C-2 forms. This radical abstracts H from HBr. The product is

CH X_{3} - CHBr - CH (CH X_{3}) X_{2}

, 2-bromo-3-methylbutane (anti-Markovnikov).

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