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JEE Advanced levelSingle correct optionDifficulty 3 of 3o4159

2-Bromo-2-methylpropane is heated with $NaOEt$ in ethanol to give a gas X. X is then treated with $HBr$ in the presence of an organic peroxide. The final product is

A1-bromo-2-methylpropane
B2-bromo-2-methylpropane
C1-bromobutane
D2-bromobutane

Answer: A

E2 elimination gives X = 2-methylpropene. With peroxide,

HBr

adds by a radical path in an anti-Markovnikov manner:

Br

goes to the less substituted carbon, giving

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

, 1-bromo-2-methylpropane.

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