(R)-Butan-2-ol is treated with $SOCl X_{2}$ and pyridine to give X. X is then treated with excess hydroxide under conditions of pure SN2 to give Y. Y is

A(R)-butan-2-ol
B(S)-butan-2-ol
Cbutan-1-ol
Dracemic butan-2-ol

Answer: A

Step 1 (SOCl2/pyridine) inverts: (R)-alcohol gives (S)-2-chlorobutane. Step 2 (SN2 with OH-) inverts again: (S)-chloride gives (R)-alcohol. Two inversions return the original configuration.

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(R)-Butan-2-ol is treated with SOClX2​ and pyridine to give X. X is then treated with excess hydroxide under conditions of pure SN2 to give Y. Y is

Answer: A

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(R)-Butan-2-ol is treated with $SOCl X_{2}$ and pyridine to give X. X is then treated with excess hydroxide under conditions of pure SN2 to give Y. Y is