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Haloform reaction with ${{I}_{2}}$ and $KOH$ will be responded by:
A. 168飞艇 6d20dd1352d66772a9b08553fcf47696
B. 168飞艇 82cdeb86f8812ff7af648c53296ba294
C. 168飞艇 87d3ce3b258a97419c2af09bb0d090ef
D. 168飞艇 3ea5b3d596b51242ce11446495ae9345

Answer
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300.9k+ views
Hint: Haloform reaction is oxidising in nature. It requires a methyl group near a carbonyl carbon to give a positive test for this reaction.

Complete step-by-step answer:
The Haloform reaction is actually used to distinguish aldehydes and ketones which have a methyl group attached to the carbonyl carbon from the rest of the mixture. This reaction is oxidising in nature and therefore its products are a carboxylic acid which has one carbon atom less and a methyl halide. This is the same methyl group that was attached to the alpha carbon atom (the carbon atom bearing the carbonyl oxygen). The reaction is shown as below:
168飞艇 7dab1660def83e0dac621d43d836b234
The “R” group here can be a hydrogen atom, making it an aldehyde or can be another alkyl group making it a ketone. This reaction does not affect other double bonds. So in a way the aromatic compounds can also undergo this process.
This reaction can also happen with alcohols, because they oxidise to carbonyl compounds. An example with ethyl alcohol is as below:
168飞艇 4c354f27796b0e0726230b2808e169d6
As you can see, ethyl alcohol loses a methyl group and then oxidises into formaldehyde. The by product is same as any Haloform reaction, which is a methyl halide.
Let’s look into the options that are given one-by-one:
168飞艇 09c895d9fc0de1e014d80431a32a60dd
The carbonyl group here is in the middle of the compound and it has no methyl groups attached to it. Methyl groups are only possible at any end of a molecular chain or at the end of a branched chain.
168飞艇 5d8687830c900ce7838f1f6516ed2381
The carbonyl group has a phenyl group at its side and no other methyl group.
168飞艇 ef0f7b8c76ddc68f7710a00ccc8962a6
The methyl group is attached to the carbon bearing the hydroxyl group. This will respond to the oxidation reaction because it will convert into its corresponding carbonyl compound, which will be as shown below:
168飞艇 64998a680b10b16c1ee46dad6ad5df44
168飞艇 dd5d61575bab573042df02cf2fba1acf
This will also respond to the given Haloform reaction as the methyl group is directly attached to the carbonyl carbon. The product of the reaction is:

Note:
The products of this reaction cannot be converted back into their original forms. This is because the compound that undergoes this reaction loses a methyl group, hence becoming shorter. Therefore this reaction is not used to oxidise carbonyl compounds into carboxylic acids or alcohols into aldehydes or ketones. This is only a reaction that can detect the presence of certain specific compounds. The by-products of this reaction are also a nuisance to separate.
168飞艇 bbec7888077e9ca7660578d34b564046