JEE Main · 2024 · 31 Jan 2024 · Shift 2 · Aldehydes Ketones and Carboxylic Acids

Identify the name reaction.

(A)Stephen reaction
(B)Etard reaction
(C)Gatterman-koch reaction✓ Correct
(D)Rosenmund reduction

Answer: (C)

Solution

Passing CO and HCl gas into benzene in the presence of anhydrous

AlC l_{3} /CuCl

generates formyl chloride in situ, which serves as the electrophile in an electrophilic aromatic substitution and installs a

- CHO

group directly on the ring, giving benzaldehyde.

This direct formylation of an aromatic ring using CO and HCl with a Lewis acid catalyst is the Gattermann–Koch reaction.

JEE Main · 2024 · 31 Jan 2024 · Shift 2 · Single correct option

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