Rhodium– and iridium–perfluorobenzenethiolato complexes, [(C5Me5)Ir(SC6F5)2], [(C5Me5)Ir(SC6F4H-p)2] and [(C5Me5)2Rh2(µ-SC6F5)3][(C5Me5)Rh(SC6F5)3]: syntheses, crystal structures and solution behaviour
Abstract
Reaction of [(C5Me5)2M2(µ-Cl)2Cl2](M = Rh 1a or Ir 1b) with Pb(SRF)2 gave [(C5Me5)Ir(SRF)2]2b(RF= C6F5 or C6F4H-p) containing five-co-ordinate IrIII, or ionic [(C5Me5)2Rh2(µ-SRF)3][(C5Me5)Rh(SRF)3]3a(RF= C6F5 or C6F4H-p) containing six-co-ordinate RhIII in both the anion and cation. Complexes 2b and 3a(RF= C6F5) were characterised by single-crystal X-ray determinations; the structures of 2b(RF= C6F5 or C6F4H-p) are very similar, but in the former the SC6F5 ligands are related by a plane of symmetry. The NMR spectra of 2b in solution are consistent with the mirror-symmetric solid-state structure. However, those of the rhodium complexes 3a, while consistent with the ionic solid-state structures in methanol, show quite different features in less-polar solvents, indicating that they participate in the equilibrium [(C5Me5)2Rh2(µ-SRF)3][(C5Me5)Rh(SRF)3]⇌ 3[(C5Me5)Rh(SRF)2] where [(C5Me5)Rh(SRF)2] has a similar structure to that of 2b(RF= C6F5). Complexes 1a and 1b reacted with Pb(SC6H4F-p)2 to give salts formulated as the triply bridged [(C5Me5)2M2(µ-SC6H4F-p)3]Cl·H2O (M = Rh 4a cr Ir 4b), while 1b reacted with Ag(SCF3) to afford the diiridium complexes [(C5Me5)2Ir2(µ-SCF3)2(SCF3)2]5b and [(C5Me5)2Ir2(µ-SCF3)3]Cl·H2O 6b.