The reaction of tetrahydrofuran-2,2-dimethanol (I) with 1 mole of octadecyl bromide (II) by means of KOH in DMSO gives the monoether (III), which is finally condensed with 2-chloro-2-oxo-1,3,2-dioxaphospholane (IV) and triethylamine in benzene to afford the target compound.