The synthesis of some monofluorophosphite esters from the appropriate hydroxy compound and PCl2F in the presence of a tertiary amine is described. The reaction of 2,2′-dihydroxy-biphenyl with PCl3 in the presence of triethylamine did not furnish the expected chlorophosphite 9; instead, the bridged bisphosphite ester, 10, was obtained. Reaction of the fluorophosphite ester 8 with 3,5-di-tert-butyl-benzoquinone furnished the spiromonofluorophosphorane 12 in which λ5P is part of a five-membered and a seven-membered ring system. Single crystal X-ray diffraction studies were conducted on compounds 2, 10 and 13. In the case of 2, crystallographic 2/m symmetry and short intermolecular P · · · O distances were observed. Compound 10 shows short intramolecular P · · · O contacts. The catechyl phosphate 13, similarly to other dialkylphosphate esters, was found to be a hydrogen-bonded dimer.