The epoxide shown is treated first with NaCN in aqueous ethanol and then with excess LiAlH4, followed by aqueous work-up. Which structure is the final product?

JEE Advanced levelSingle correct optionDifficulty 3 of 3o3275

The epoxide shown is treated first with $NaCN$ in aqueous ethanol and then with excess $LiAlH X_{4}$ , followed by aqueous work-up. Which structure is the final product?

The compound is 2,2-dimethyloxirane. Cyanide attacks the less hindered CH2, giving 3-hydroxy-3-methylbutanenitrile,

HOC (CH X_{3}) X_{2} CH X_{2} CN

LiAlH X_{4}

reduces the nitrile to a primary amine without affecting the tertiary alcohol, giving 4-amino-2-methylbutan-2-ol, CC(C)(O)CCN.