Stereoselective Synthesis of Glycosyl Phosphonates from Saccharides Via Selenium-Catalyzed Dehydrogenations.

Glycosyl diphenylphosphonates are a type of glycosyl donor featuring a phosphorus-containing leaving group at the anomeric carbon, and their coupling reaction has been extensively studied in oligosaccharide synthesis. Herein, we have developed an efficient and green synthetic method for the direct dehydrogenative coupling of glucose derivatives with secondary phosphine oxides under ambient air, using a catalytic amount of diaryl diselenide. This method eliminates the need for glycosyl chlorides and phosphorochloridates, as well as preactivated reagents such as N-methylimidazole. Water is generated as the sole byproduct. The system exhibits broad compatibility with monosaccharides and furanose derivatives (e.g., glucose, mannose, and galactose), enabling the synthesis of glycosyl phosphonate compounds in high yields (up to 93%) and with excellent β-selectivity.