Copper-Catalyzed Phosphonation-Annulation Approaches to the Synthesis of β-Phosphonotetrahydrofurans Involving C-P and C-O Bonds Formation.

Substituted tetrahydrofuran derivatives play important roles as biological activities. A versatile method for the synthesis of β-phosphonotetrahydrofurans has been developed based on Cu-catalyzed difunctionalization of alkenes. This transformation would provide a new pathway for the formation of Csp(3)-P and Csp(3)-O bonds in one step. Furthermore, this copper catalyst system can be used in the synthesis of β-phosphonotetrahydropyrans and phosphono-γ-butyrolactones. These reactions were also performed well by using 3 equiv of Mn(OAc)3·2H2O as the oxidant without copper catalyst.