We report on the successful synthetic procedure for the conversion of 5'-monophosphorylated 2'-deoxydinucleotides into their 5'-triphosphate derivatives in satisfactory to excellent yields. The activation of the terminal phosphate group was achieved under the Mukaiyama conditions in the presence of a nucleophilic catalyst. The reaction conditions (solvent, counter ions, activation time and reagent excess) were optimized for all dinucleotides.