Crystal and molecular structure of acb[1,2-bis(trifluoromethyl)-3-acetyl-4-oxopent-1-enyl-O′,O,C1]-fde{1,4–5,β-η-[bis(trifluoromethyl)-ethylene]oct-4-enyl}iridium(III): an addition product of hexafluorobut-2-yne with co-ordinated cyclo-octa-1,5-diene

Abstract

The structure of the title compound has been determined from X-ray diffractometer data by the heavy-atom method. Crystals are triclinic, space group P, with a= 13.415 ± 0.015, b= 11.448 ± 0.012, c= 8.435 ± 0.009 Å. α= 70.2 ± 0.4, β= 113.6 ± 0.5. γ= 103.5 ± 0.5°. Block-diagonal least-squares refinement of the atomic-parameters converged at R 0.048 for 4 642 reflections. The compound is shown to have been formed by 1.4-addition of hexafluorobut-2-yne to an acetylacetonatoiridium ring, with a second acetylene molecule inserted between the metal and an olefinic carbon atom. Bond lengths are: Ir–O 2.183, 2.240; Ir–C 2.061, 2.006, 2.075; and Ir–C (olefin) 2.269, 20347Å. The molecular geometry is compared with that in related molecules.