β-Halovinylsilanes in oligoyne synthesis: a fluoride-catalysed unmasking of alkynes from β-fluorovinylsilanes

A stereoselective halodestannylation of (E)-β-stannylvinylsilane 6 has been used to access a range of (E)-β-halovinylsilanes. Most notably, the β-fluorovinylsilane 14 was accessed in high yield using the Selectfluor® reagent, and subsequently converted into a masked hexayne 22. Release of the hexayne 25 was achieved by exposing 22 to sub-stoichiometric quantities of fluoride.