Question

Match the following:

• A. A-III, B-I, C-II, D-IV
• B. A-II, B-III, C-I, D-IV
• C. A-II, B-IV, C-I, D-III
• D. A-III, B-IV, C-II, D-I

Hint:

Remember: Rosenmund--Pd/BaSO\(_4\), Stephen--SnCl\(_2\)/HCl, Etard--CrO\(_2\)Cl\(_2\), Gattermann-Koch--CO + HCl/AlCl\(_3\).

Answer 1

The Correct Option is C

Concept: Important named reactions of aldehyde preparation:
• Rosenmund reduction : \(H_2/Pd-BaSO_4\)
• Stephen reaction : \(SnCl_2/HCl\) followed by hydrolysis
• Etard reaction : \(CrO_2Cl_2\)
• Gattermann-Koch reaction : \(CO+HCl/AlCl_3\)

Step 1: Match Rosenmund reaction.
\[ RCOCl \xrightarrow{H_2/Pd-BaSO_4} RCHO \] Therefore, \[ A \rightarrow II \]

Step 2: Match Stephen reaction.
\[ RCN \xrightarrow{SnCl_2/HCl} RCH=NH \] followed by hydrolysis gives aldehyde. Hence, \[ B \rightarrow IV \]

Step 3: Match Etard reaction.
\[ C_6H_5CH_3 \xrightarrow{CrO_2Cl_2} C_6H_5CHO \] Therefore, \[ C \rightarrow I \]

Step 4: Match Gattermann-Koch reaction.
\[ ArH + CO + HCl \xrightarrow{AlCl_3/CuCl} ArCHO \] Thus, \[ D \rightarrow III \] \[ \boxed{A-II,\ B-IV,\ C-I,\ D-III} \] Hence, \[ \boxed{\text{Correct Option (3)}} \]