Dehydroxylative Reduction of Pyridinemethanols in Water by a Diazabenzacenaphthenium Photoredox Catalyst

Abstract

Water represents an ideal reaction medium for green chemistry. However, the scarcity of water‐soluble catalysts has long hampered the expansion of organic synthesis in water as a sole solvent. Herein, we report that the diazabenzacenaphthenium cation N‐BAP serves as a water‐soluble photoredox catalyst that enables the visible light‐induced dehydroxylative reduction of pyridinemethanol derivatives in water. Notably, N‐BAP is sufficiently potent to reduce pyridinemethanol derivatives without requiring strong acidic additives to enhance the electron‐accepting ability. This study highlights the utility of N‐BAP as a highly reducing photoredox catalyst capable of operating efficiently in aqueous environments.