4. Electrochemical chlorination of 1,3-dicarbonyls

A recent paper of Prof. Fumitoshi Kakiuchi et al. (from Keio University in Yokohama, Japan) deals with the copper-catalysed α-chlorination of 1,3-dicarbonyl compounds.

You might be thinking that it is just another paper on an overused method, but there is a twist here that I particularly liked. The source of chlorine here is nothing but hydrochloric acid, probably the cheapest and simplest source of chlorine atoms, without the issue of handling a toxic gas like Cl2. I guess there is no point in mentioning N-chlorosuccinimide. The trick for the transformation of a fairly inert Cl into a formal Cl+ is the use of electrochemistry. A mild current at the appropriate intensity provides just enough oxidation to provide monochlorinated 1,3-dicarbonyls in ok-to-high yields.

4.a

While I doubt I will ever use this method in a lab (I am not too experienced with organic electrochemistry), I can see the potential of it on an industrial scale: reducing costs of reagents, reducing waste, and perhaps you could even use the H2 produced by the reaction to power an auxiliary generator or something.

Asian J. Org. Chem. 2013, 2, 935-937 link

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