The product $A$ in the following reaction is:
$CH_3-CH=CH-CH_2-CN \xrightarrow[(2) H_3O^+]{(1) DIBAL-H, -78^{\circ}C} A$

Among the following reagents,which one can convert an ester into an aldehyde?

Match the following:
| List-$I$ | List-$II$ |
| :--- | :--- |
| $(A)$ Acid chloride to aldehyde | $(I)$ $DIBAL-H$ |
| $(B)$ Benzene to benzaldehyde | $(II)$ $CO, HCl, \text{anhyd. } AlCl_3$ |
| $(C)$ Acetylene to aldehyde | $(III)$ $HgSO_4, H_2SO_4$ |
| $(D)$ Ester to aldehyde | $(IV)$ $H_2, Pd-BaSO_4$ |

Which of the following is a Stephen reaction?

What is the product formed when side chain chlorination of toluene is carried out followed by acid hydrolysis at $373 \ K$?

Identify the name of the following reaction: $C_6H_5CH_3$ $\xrightarrow[CS_2]{CrO_2Cl_2} A$ $\xrightarrow{H_3O^+} C_6H_5CHO$