Fig. 5. Substrate scope for late-stage fluorination of alkyl phosphonates via electrophilic activation.

a Fluorination of diethyl phosphonates. ^aConversions determined by ³¹P NMR. ^bIsolated yield. ^cTf₂O (3.0 eq.), Py (4.0 eq.). b An exemplification of the method’s application in the synthesis of FPBP, a fatty acid amide hydrolase inhibitor. c Fluorination of monoethyl phosphonates. d Late-stage fluorination of alkyl phosphonates derived from drug molecules.