Coupling of terminal alkynes with 5-iodo-1-(2, 3, 5-tri-Op-toluyl-~-~-arab~ nofuranosyl) uracil and 5-iodo-3', 5'-di-0-p-toluyl-2'-deoxyuridine proceeded readily in triethylamine with catalytic quantities of bis (tripheny1phosphine)-palladium (I1) chloride and copper (1) iodide. The resulting products were deprotected to give 5-alkynyl-l-@-~- arabinofuranosyluracil and 5-alkynyl-2'-deoxyuridine nucleosides. The 5-ethynyl, followed ...