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Since the mechanism involves formation of free radical so is it possible to yield a ketone from wurtz reaction of acyl chloride Such as CH3COCl reacts with Na in dry ether so can it yield CH3COCH3

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  • $\begingroup$ No, and if someone tried it could end up quite badly. And ketones themselves react with sodium... Also don't write posts like were scribbling. $\endgroup$
    – Mithoron
    Commented Feb 28, 2023 at 16:56
  • $\begingroup$ @Mithoron if we speak ok theoritical grounds only , and take 1 mol of each quantity then ? $\endgroup$ Commented Feb 28, 2023 at 17:21
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    $\begingroup$ The answer is: Boom! Or theoretically ist could be: Bang! $\endgroup$ Commented Feb 28, 2023 at 17:52

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Acid chlorides are completely different entity compared to alkyl chlorides. You cannot expect both give similar (or closely related) products when reacted with metallic sodium. But, interestingly there are a reaction between acid chloride and sodium or potassium metal, yet it is not a boom or bang (sorry Martin!) according to reference 1. Ref. 1 states that:

Sodium reacts with benzoyl chloride in anhydrous ether solution to give ethyl benzoate as the main product. This reaction, with other metals, was reported by Varvoglis (Ref.2). However, sodium or potassium reacts with benzoyl chloride in dry xylene to give benzoic anhydride and sodium chloride.

Under the same conditions in dry xylene, the reaction of p-toluenesulfonyl chloride with potassium or sodium behave differently to give disulfone instead of anhydride (Ref.1).

Lucky for Martin (:-)), these mixtures are not safe enough if you don't know what you are doing. For instance, if you mix propionyl chloride and diisopropyl ether, there would be a bang even without sodium or potassium metal (Ref.3). Just for your information:

Mixtures of propionyl chloride with diisopropyl ether are very unstable. The exothermic reaction giving isopropyl propionate and isopropyl chloride has a $\Delta H_\pu{25 ^\circ C}$ of $\pu{-10 kcal mol-1}$ and a $\Delta G_\pu{25 ^\circ C}$ of $\pu{-11 kcal mol-1}$ , and can proceed spontaneously.

The reaction also has catalyzed by some metal salts such as $\ce{ZnCl2}$ in very dilute conditions (even about $\pu{4 ppm}$ levels). Thus, as you have seen, you may not allowed to react any acid chlorides in any ether of choice in the presence of alkali metals.

Edit:

In a recent publication suggested that the reaction of benzoyl chloride in THF/benzene in the presence of magnesium metal has undergone to form the corresponding diketone, $\ce{PhC(O)C(O)Ph}$ (Ref.4).


References:

  1. Irwin A. Pearl, Theodore W. Evans, and William M. Dehn, "Reactions of Sodium and Potassium on Acid Chlorides," J. Am. Chem. Soc. 1938, 60(10), 2478–2480 (ODI: https://doi.org/10.1021/ja01277a054).
  2. According to the authors of Ref.1, Varvogli has treated acid chlorides in absolute ether with a large number of metals. Of all the metals tried, only iron and zinc were effective, and these yielded ethyl esters of the respective adds. On the basis of this work, potassium and sodium probably would have been predicted to be without action: G. A. Varvoglis, "Uber die Einwirkung von Metallen auf Samechlorid," Ber. 1937, 70, 2391-2396.
  3. W. M. B. Könst, "The hazard of a propionyl chloride-diisopropyl ether mixture," Journal of Hazardous Materials 1981, 4(3), 291-298 (ODI: https://doi.org/10.1016/0304-3894(81)80007-6).
  4. S. V. Maslennikov, V. P. Sergeeva, I. V. Spirina, and S. V. Kazakina, "Oxidation of Magnesium with Benzoyl Chloride in a Mixture of Tetrahydrofuran and Benzene," Russian Journal of General Chemistry 2002, 72(5), 678-680 (ODI: https://doi.org/10.1023/A:1019583513232).
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    $\begingroup$ It's mostly the difference in reactivity between aromatic and aliphatic acyl chlorides. Still, I think reaction with pure chloride could be overly even for aromatic one and you overestimate this reaction with ether. Pretty interesting nonetheless. $\endgroup$
    – Mithoron
    Commented Mar 1, 2023 at 22:21

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