MgBr₂·OEt₂-Promoted Coupling of Ketones and Activated Acyl Donors via Soft Enolization: A Practical Synthesis of 1,3-Diketones

 

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Abstract

Ketones undergo soft enolization and acylation on treatment with MgBr₂·OEt₂, i-Pr₂NEt, and various acylating agents to give 1,3-diketones. The process is particularly efficient for N-acylbenzotriazoles and O-pentafluorophenyl esters, and, in these cases, is conducted using untreated, reagent grade CH₂Cl₂ open to the air, thus providing an exceptionally simple approach to the synthesis of this important class of compounds.

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