Iridium(III)-vinylidene chemistry: Conversion of an iridacyclopentadiene-chlorido complex and terminal alkynes to iridacyclopentadiene-vinyl complexes

Under anhydrous conditions, reaction of [κ2(C1,C4)-CRCRCRCR](PPh3)2Ir(Cl) and 2-propyn-1-ol generates a [2 + 2 + 2] cycloaromatization product. Under aqueous conditions the same reactants form iridium-vinyl complexes bearing the general structure [κ2(C1,C4)-CRCRCRCR](PPh3)2Ir(CO)(κ1-vinyl). In these, the CO ligand is derived from a terminal alkyne carbon and an oxygen atom from water.