CONVERSION OF NUCLEOSIDE H-PHOSPHONATE MONOESTERS TO THE CORRESPONDING H-PHOSPHONOTHIOATES - P-31 NMR-STUDIES

P-31 NMR Studies on the conversion of nucleoside H-phosphonate monoest ers into the corresponding H-phosphonothioates revealed that the key i ntermediate, the nucleoside trimethylsilyl pivaloyl phosphite 3, may u ndergo under the reaction conditions at least two parallel transformat ions to, most likely, the nucleoside trimethylsilyl chlorophosphite 6 and the monosilylated nucleoside H-phosphonate 5.