text: Although vinylidenes are only transient species, they are found as ligands in organometallic chemistry.  They typically arise by the protonation of metal acetylides or by the reaction of metal electrophiles with terminal alkynes.  The complex chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium readily forms such complexes:
  :CpRu(PPh)Cl  +  RCH  +  KPF   →    [CpRu(PPh)(=C=C(H)Ph]PF  +  KCl