Abstract
Reported herein is the development of an intramolecular oxidative cyclization of ketoximes with alkenes for the preparation of isoquinoline N-oxides. The reaction, which utilizes phenyliodine bis(trifluoroacetate) (PIFA) as an oxidant and 2,2,2-trifluoroethanol (TFE) as a solvent, proceeds to afford various N-heterocyclic products, including aryl/heteroaryl-fused pyridine N-oxides, isoindole N-oxides, and 2-benzazepine derivatives. Preliminary experimental and computational mechanistic studies suggest that the ionic pathway is the primary mechanism. The synthetic utility of the developed method was highlighted via several product transformations.