Question

Identify the suitable reagent for the following conversion: $Ph-C(=O)-OCH_3$ $\longrightarrow$ $Ph-CHO$

• A. (i) $AlH(iBu)_{2}$ (ii) $H_{2}O$
• B. (i) $NaBH_{4}$, (ii) $H^{+}H_{2}O$
• C. $H_{2}$ $Pd-BaSO_{4}$
• D. (i) $LiAlH_{4}$, (ii) $H^{+}$$H_{2}O$

Hint:

Use DIBAL-H for selective reduction of esters to aldehydes; LiAlH\textsubscript{4} over-reduces to alcohols.