We propose the new approach to the synthesis of 5'-triphosphate derivatives of natural and modified dinucleotides with expanded functionality. Our strategy includes the combination of the solution phase synthesis of necessary dimers using the wide range of nucleic acids chemistry methods and the subsequent introduction of the triphosphate residue. A number of the new potential substrates for the template dependent synthesis of nucleic acids with expanded functionality are obtained, namely, 5'-triphosphates of dinucleotides containing the functionally active groups in heterocyclic bases, in carbohydrate-phosphate backbone, and the groups mimicking the residues of natural amino acids. The abilities of the proposed synthetic route are also demonstrated by the synthesis of 5'-triphosphates of dinucleotides with modified carbohydrate-phosphate backbone.