EFFICIENT METHOD FOR THE PREPARATION OF NUCLEOSIDE PHOSPHOROFLUORIDATES AND NUCLEOSIDE PHOSPHOROFLUORIDOTHIOATES

Dinucleoside H-phosphonates and dinucleoside H-phosphonothioates can b e efficiently transformed to the fluorophosphate and fluorothiophospha te diester derivatives rin iodine promoted oxidation in the presence o f fluoride anions. An analogous oxidation of the presilylated nucleosi de H-phosphonate or nucleoside H-phosphonothioate monoesters furnished rapid formation of the corresponding phosphorofluoridate or the phosp horofluoridothioate monoesters.