Synthesis of α-Acyloxyketone Derivatives via the Platinum-Catalyzed Migration of Propargylic Esters

Abstract

The synthesis of α-acyloxyketones via the migration of a propargylic ester followed by the intramolecular nucleophilic addition of the resulting allene was achieved using a cationic platinum catalyst. The optimized conditions for this transformation were determined to be 3 mol% of Pt(cod)Cl₂, 3 mol% of AgNTf₂, and 3 eq of water in toluene at 100°C, and these conditions were successfully applied to the synthesis of a wide variety of α-aryl-α-acyloxyketones. The mechanism of this reaction was evaluated in detail based on the results of isotope labeling experiments using H₂¹⁸O.

Graphical Abstract