An unknown aldehyde ‘A’ on reacting with alkali gives a - hydroxy… - Vidyadip

Question

An unknown aldehyde ‘$A’$ on reacting with alkali gives a $ \beta-$ hydroxy aldehyde, which loses water to form an unsaturated aldehyde, $ 2-$ butenal. Another aldehyde ‘$B’$ undergoes disproportionation reaction in the presence of conc. alkali to form products $C$ and $D. C$ is an arylalcohol with the formula, $\ce{C_7H_8O}$.

Identify $A$ and $B$.
Write the sequence of reactions involved.
Name the product, when ‘$B$’ reacts with zinc amalgam and hydrochloric acid.

✓

Answer

is $\ce{CH_3CHO} \ ($ethanal$)$.
is $\ce{C_6H_5CHO} \ ($benzaldehyde$)$.
Toluene.

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