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Question: **ASSERTION:** Ethyl acetoacetate will give the iodoform test. **REASON:** It contains the\[C{H_3}...

ASSERTION: Ethyl acetoacetate will give the iodoform test.
REASON: It contains theCH3COC{H_3}CO group linked to a Carbon atom.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
C. Assertion is incorrect but Reason is correct.
D. Both Assertion and Reason are incorrect.

Explanation

Solution

We need to see that ethyl acetoacetate gives iodoform test. We can find out by looking for CH3COC{H_3}CO group at the end of the chain which is necessary for an iodoform test. Acetoxy (CH3COC{H_3}CO) group as well as CH3CH(OH)C{H_3}CH(OH) - gives the iodoform test.

Complete step by step solution:
Carbonyl compounds (aldehydes and ketones having methyl group CH3C{H_3} group at position) give the iodoform test.
Ethyl acetoacetate CH3COCH2COOCH2CH3C{H_3}COC{H_2}COOC{H_2}C{H_3} is a carboxylic acid derivative, more specifically an ester.
Carboxylic acid derivatives do not give the iodoform test. This is due to resonance the does not remain freely available which is needed for the reaction to take place.
Even though ethyl acetoacetate contains CH3COC{H_3}CO, an acetoxy group yet it does not give the iodoform test. This is because the -atoms of the CH2C{H_2} group are attached to the electron-withdrawing group making them more acidic than the - atom of CH3C{H_3} group. As a result, the iodination will take place at the more acidic position, which is at CH2C{H_2} group and thus CH3IC{H_3}I will not be formed.
Thus, the assertion is incorrect.
Ethyl acetoacetate CH3COCH2COOCH2CH3C{H_3}COC{H_2}COOC{H_2}C{H_3} does have a CH3COC{H_3}CO attached to a Carbon atom. So, from the structure the reason is correct.

**Therefore, option C is correct.

Additional information: **
The iodoform test is used to detect carbonyl compounds. Some alcohols having the structure RCH(OH)CH3R - CH(OH) - C{H_3} always form precipitate, giving a positive iodoform test. Ethyl alcohol gives a positive iodoform test.

Note:
CH3IC{H_3}I precipitates as a yellow solid and confirms the iodoform test. The students need to pay attention that the mere presence of CH3COC{H_3}CO group in Ethyl acetoacetate is not a confirmatory parameter to decide whether or not the compound gives the iodoform test.
In reaction with Iodine in an alkaline medium, the CH2C{H_2} group reacts more rapidly than the methyl group of CH3COC{H_3}CO, preventing the formation of iodoform.