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NEET levelSingle correct optionDifficulty 1 of 3o2172

3-Methylbut-1-ene reacts with $HBr$ in the absence of peroxide. The major product is

A2-bromo-3-methylbutane
B1-bromo-2-methylbutane
C1-bromo-3-methylbutane
D2-bromo-2-methylbutane

Answer: D

Protonation gives the secondary cation

(CH X_{3}) X_{2} CH - CH X^{+} - CH X_{3}

. A 1,2-hydride shift converts it into the tertiary cation

(CH X_{3}) X_{2} C X^{+} - CH X_{2} CH X_{3}

, which is captured by bromide to give 2-bromo-2-methylbutane.

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