Ni–Pd Catalyzed Cyclization of Sulfanyl 1,6-Diynes: Synthesis of 1′‑Homonucleoside Analogues

The Ni–Pd catalyzed addition–cyclization of sulfanyl 1,6-diynes <b>2</b>–<b>9</b> with nucleobases is described. The reactions of <i>N</i>-tethered 1,6-diynes with <i>N</i>³-benzoylthymine, <i>N</i>⁴,<i>N</i>⁴-bis­(Boc)­cytosine, <i>N</i>³-benzoyluracil and <i>N</i>⁶,<i>N</i>⁶-bis­(Boc)­adenine exclusively afforded the pyrrolylmethyl and furylmethyl nucleotides in good yields. Deprotection of nucleobases was completed by treatment with acids or bases. Furthermore, the reactions of pyrroles and furans with nucleophiles such as alkoxides and amines underwent detosylation and conversion to the alkoxymethyl- and arylaminomethyl-pyrroles and furans in good yields