A facile method to construct cyclic α,α-difluoromethylenephosphonate—A novel cyclic phosphate mimic

A facile and efficient synthesis of cyclic α,α-difluoromethylenephosphonates by halogen-induced intramolecular cyclization of β-allenic α,α-difluoromethylenephosphonates is described. The protocol gives multi-substituted six-membered phosphonates with high regioselectivity, providing a new entry to the cyclic phosphate mimics which is still an unexplored but promising area.