Q. Which of the following reactions would give propanal?

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Ethyl propanoate $+$ DBAH (diisobutyl aluminium hydride). $\left.\left[\left(i- C _{4} H _{9}\right)_{2} AlH \right)\right]$ at $-70^{\circ} C$, followed by hydrolysis.

Propyl propanoate + DIBAL-H/ $H _{2} O$

Ethyl cyanide + DBAH

Propanoyl chloride + LBAH

Solution:

Correct answer is (a) Ethyl propanoate $+$ DBAH (diisobutyl aluminium hydride). $\left.\left[\left(i- C _{4} H _{9}\right)_{2} AlH \right)\right]$ at $-70^{\circ} C$, followed by hydrolysis.Correct answer is (b) Propyl propanoate + DIBAL-H/ $H _{2} O$Correct answer is (c) Ethyl cyanide + DBAHCorrect answer is (d) Propanoyl chloride + LBAH

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