Abstract: The preparation and characterization of the first acetylenic esters of any kind (alkynyl tosylates, RC= COTs, and mesylates, RCXOM s) is reported. A simple, two-step procedure, starting from commercially available iodosobenzene diacetate, was employed in the synthesis. The final step involved ligand-ligand coupling in a tricoordinate iodonium species, C6H51-(OTs) C= CR, via metal complexing. X-ray data indicate an ionic structure ...