Alkyl Sulfoxides as Radical Precursors and Their Use in the Synthesis of Pyridine Derivatives

We report here the use of simple and readily available alkyl sulfoxides as precursors to radicals and their application in the preparation of pyridine derivatives. We show that alkyl sulfoxides form EDA complexes with N-methoxy pyridinium salts, which upon visible light irradiation, undergo a cascade of radical processes to afford pyridine derivatives smoothly. This method displays broad scope with respect to both reactants. The synthetic versatility of sulfoxides as a handle in chemistry adds to the power of this transformation. The method is further applied in the synthesis of various pyridyl C–glycosides that are previously difficult to access.