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Amongst the following compounds, the one that will not respond to Cannizzaro reaction upon treatment with alkali is
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The correct answer is:
$\mathrm{Cl}_{3} \mathrm{CCHO}$
For a carbonyl group to give Cannizaro reaction, it should not have an $\alpha$ -hydrogen atom. Among the given compound $\mathrm{Ne}_{3} \mathrm{CCHO}, \mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CHO}$ and HCHO respond
to Cannizaro reaction but $\mathrm{Cl}_{3} \mathrm{CCHO}$ do not due to the following reason.
When hydroxyl group attacks the carbonyl group a tetrahedral intermediate forms. This tetrahedral intermediate will revert to a carbonyl compound by
expelling the best leaving group. The CCl $_{3}$ carbonium is resonance stabilised therefore it is better leaving group than OH. These initial products exchange a proton to give ion of carboxylic acid and trichloromethane ($CHCl_{3}$).
to Cannizaro reaction but $\mathrm{Cl}_{3} \mathrm{CCHO}$ do not due to the following reason.
When hydroxyl group attacks the carbonyl group a tetrahedral intermediate forms. This tetrahedral intermediate will revert to a carbonyl compound by
expelling the best leaving group. The CCl $_{3}$ carbonium is resonance stabilised therefore it is better leaving group than OH. These initial products exchange a proton to give ion of carboxylic acid and trichloromethane ($CHCl_{3}$).
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