Modified nucleoside mono- (dA(R)MPs and dC(R)MPs) and triphosphates (dA(R)TPs and dC(R)TPs) bearing bipyridine or terpyridine ligands attached via acetylene linker were prepared by single-step aqueous-phase Sonogashira cross-coupling of 7-iodo-7-deaza-dAMP or -dATP, and 5-iodo-dCMP or -dCTP with the corresponding bipyridine- or terpyridine-linked acetylenes. The modified dN(R)TPs were successfully incorporated into the oligonucleotides by primer extension experiment (PEX) using different DNA polymerases and the PEX products were used for post-synthetic complexation with Fe(2+).