Regioselective Addition of 1,3-Dicarbonyl Dianions to Carbonyl Compounds: One Pot Lactonization and Ketalization of 8-Hydroxy-β-keto Esters to Protected Pyrone Derivatives

摘要

A simple and efficient strategy for the synthesis of 6-substituted-2-pyrone derivatives, by BF3·OEt2 mediated one pot cyclization and keto-protection of δ-hydroxy-β-keto esters, obtained via regioselective addition of 1,3-dicarbonyl dianion of ethyl acetoacetate to aldehydes and ketones is described.