AIPMT – 2010

Hint: The compound containing methyl ketone and secondary alcohol gives the iodoform test.

The compound containing  and gives the iodoform test.

Step 1:

Compounds having ${\mathrm{H}}_3\mathrm{C}-\mathrm{CO}-$ group and ${\mathrm{CH}}_3\mathrm{CH}\left(\mathrm{OH}\right)-$ gives iodoform when heated with Iodine and NaOH.

Step 2:

Among the following compounds CH₃CH₂OH, CH₃COCH₃  and propan-2-ol  will give iodoform test.
Ethanol is the only primary alcohol to give the triiodomethane (iodoform) reaction.

Hence, the second option is the correct answer.

Hint: The first reaction is an oxidation reaction and the second reaction is an electrophilic aromatic substitution reaction.

Alkaline KMnO₄is a strong oxidizing agent and therefore it oxidizes the whole carbon chain directly attached to the benzene nucleus into the –COOH group.

Furthermore, the Br₂ group in the presence of a halogen carrier causes bromination whereas ethyl alcohol in an acidic medium results in esterification.