Photochemical C–H Silylation and Hydroxymethylation of Pyridines and Related Structures: Synthetic Scope and Mechanisms
Fatima Rammal, Di Gao, Sondes Boujnah, Aqeel A. Hussein, Jacques Lalevée, Annie−Claude Gaumont, Fabrice Morlet‐Savary, Sami Lakhdar
Abstract
Considering the synthetic relevance of heteroarenes in various areas ranging from organic synthesis to medicinal chemistry, developing practically simple methodologies to access functionalized heteroarenes is of a significant value. Described herein is an efficient approach for C–H silylation and hydroxymethylation of pyridines and related heterocycles by the combination of silanes or methanol with readily available N-methoxypyridinium ions with a low catalyst loading (2 mol %) under blue light irradiation. The synthetic importance of the developed reactions is demonstrated by the synthesis of biologically relevant compounds. Electron paramagnetic resonance spectroscopy, quantum yield measurements, and density-functional theory calculations allowed us to understand reaction mechanisms of both photocatalytic reactions.