Two-centre oxidative addition of hexafluorobut-2-yne to a bis(µ-pyrazolyl)di-iridium(I) complex leading to bridge-elimination via H-transfer from co-ordinated cyclo-octa-1,5-diene: X-ray crystal structure of a mixed-bridge, mixed-valence iridium dimer incorporating a 1–3,5,6-η-C8H11 lignad

Abstract

Reaction of the unsymmetrically-bridged di-iridium(I) complex [(cod)Ir(µ-pz)(µ-fpz)Ir(cod)], [cod = cyclo-octa-1,5-diene; pzH = pyrazole; fpzH = 3,5-bis(trifluoromethyl)pyrazole] with hexafluorobut-2-yne (C₄F₆) leads to bridge-replacement of µ-fpz by C₄F₆; the latter is incorporated in a parallel-type bonding mode to give a di-iridium product having Ir–Ir 2.85 Å and one Ir centre terminally co-ordinated by a 1–3,5,6-η-C₈H₁₁(i.e.-dienyl) unit.