3-Hydroxy-4-pyridones, which are easily prepared from commercially available 3-hydroxy-4- pyrones, can be readily transformed into 4-methoxy-3-oxidopyridinium ylides by treatment with methyl trifluoromethanesulfonate and subsequent deprotonation with a non- nucleophilic base. These ylides are capable of undergoing cycloaddition to several electron- deficient alkenes, thus allowing the synthesis of highly functionalized azabicyclo [3.2. 1] ...
