Abstract A rapid and diverse synthesis of biologically important 6-substituted-5, 6-dihydro-4- hydroxy-2-pyrones through a double Reformatsky reaction of aldehydes to δ-hydroxy-β- ketoesters followed by lactonization is described. Due to the high functional group tolerance and reaction site discrimination between aldehyde, nitrile, and ester groups in the substrate, the protocol can provide the dihydropyrones with bromo, nitro, carboxylic acid, and β- ...
