Synthesis of γ-butyrolactones containing α,α-difluoromethylenyl bisphosphonate initiated by Na2S2O4

Diethyl iododifluoromethylphosphonate (1) reacted with 4-pentenoic acids in the presence of Na2S2O4 in aqueous acetonitrile solution at ambient temperature to afford various γ-butyrolactones containing α,α-difluoromethylenyl bisphosphonate moiety in moderate to good yields.