Chemistry - Carbonyl compounds Question with Solution | TestHub

DIBAL-H i.e., Di isobutyl aluminium hydride causes partial reduction of cyanide group along with the ester group and further hydrolysis forms corresponding aldehyde as the product. The reaction is as follows,

${\mathrm{CH}}_3{\left({\mathrm{CH}}_2\right)}_5{\mathrm{COOC}}_2{\mathrm{H}}_5\stackrel{\text{ DIBAL- }\mathrm{H},{\mathrm{H}}_2\mathrm{O}}{\to }{\mathrm{CH}}_3{\left({\mathrm{CH}}_2\right)}_5\mathrm{CHO}$

The Clemmensen reduction is a reaction that is used to reduce aldehydes or ketones to alkanes using hydrochloric acid and zinc amalgam.

${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{COC}}_6{\mathrm{H}}_5\stackrel{\mathrm{Zn}\left(\mathrm{Hg}\right)\&\text{ conc. }\mathrm{HCl}}{\to }{\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{CH}}_2{\mathrm{C}}_6{\mathrm{H}}_5$

A Grignard reagent is an organomagnesium compound which can be described by the chemical formula ‘R-Mg-X’ . Here aldehyde will react with Grignard's reagent to give alcohol.

${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{CHO}\underset{{\mathrm{H}}_2\mathrm{O}}{\overset{{\mathrm{CH}}_3\mathrm{MgBr}}{\to }}{\mathrm{C}}_6{\mathrm{H}}_5\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_3$

${\mathrm{CH}}_3{\mathrm{COCH}}_2{\mathrm{COOC}}_2{\mathrm{H}}_5\stackrel{{\mathrm{NaBH}}_4,{\mathrm{H}}^{+}}{\to }{\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_2{\mathrm{COOC}}_2{\mathrm{H}}_5$

In this reaction, ${\mathrm{NaBH}}_4,{\mathrm{H}}^{+}$ is used as a reducing agent, to get ${\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right){\mathrm{CH}}_2{\mathrm{COOC}}_2{\mathrm{H}}_5$ as a product.

Hence option B is the answer.