acyl halide can also give ketones by reacting with grignard's reagent but this is not done y?i didnt understand...once mam answered the ques but i didnt got the answer n replied to answer in more detalis but i didnt got reply so m postiing it once agian

Yes! Acyl halide can also give ketones by reacting with Grignard's reagent but this is not done due to the following reason.

 if we use Grignard's reagent to acid chloride, the carbon part of the Grignard's reagent will go to the carbonyl carbon of the acid chloride , and the MgX part of the grignard reagent goes to the Cl part of acid chloride , but the ClMgX part is not a good leaving group hence grignard reagent is not used.

But, if we use dialkyl cadmium, the alkyl group goes to the carbonyl carbon and cadmium reacts with Cl and removes it from the acid chloride and forms cadmium dichloride which is a stable compound.

2R'COCl + R2Cd →  2R'COR + CdCl2

The another reason to use dialkyl cadmium in place of Grignard reagent to derive ketone from acid chlorides is that Grignard reagent is more reactive than dialkyl cadmium. If Grignard reagent is used, it will react with ketone formed in the reaction to give ultimately 3° alcohol.

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