Rhodium(III) and iridium(III) half-sandwich complexes with tertiary arsine and stibine ligands

The syntheses of rhodium(III) and iridium(III) half-sandwich complexes containing tertiary arsine and stibine ligands of the form [Cp*M(L)Cl-2] (M = Rh, ft; L = AsEt3, AsPh3, SbPh3) are reported. These compounds represent infrequent examples of rhodium and iridium metal complexes bearing arsenic or antimony ligands. All new compounds were fully characterised using H-1 and C-13 NMR spectroscopy, mass spectrometry and single crystal X-ray diffraction. DFT calculations show the formation of the complexes from (Cp*MCl2)(2) and EPh3 (E = P, As, Sb) to be highly exothermic, although the enthalpic driving force is decreasing in the expected sequence P > As > Sb. (C) 2015 Elsevier BY. All rights reserved.