A direct synthesis of 3-acyl-4-hydroxy-2-pyranone derivatives via palladium-catalyzed carbonylation of α-chloroketones. A cascade reaction involving acylketenes

A simple and direct method to obtain 3-acyl-4-hydroxy-2-pyranone derivatives by the palladium-catalyzed carbonylation of a-chloroketones has been described. The methodology can be applied to a variety of aromatic and aliphatic ketones to afford valuable products from both a synthetic and a biological point of view. A mechanistic hypothesis involving an acylketene intermediate has also been proposed