Complexes of iridium(III) and rhodium(III) with metallated and unmetallated dimethyl(1-naphthyl)- and methylphenyl(1-naphthyl)-phosphine

Abstract

Dimethyl(1-naphthyl)phosphine (L) is readily metallated in the 8-(peri-)position by iridium (III), (C₁₀H₆PMe₂ P–C). Thus iridium trichloride with L in 2-methoxyethanol gives [IrCl₂(P–C)L₂]. In the presence of a base and alcohol further metallation occurs to give [IrCl(P–C)₂L] and then [IrH(P–C)₂L], which on pyrolysis gives the trimetallated complex fac-[Ir(P–C)₃]. [IrHCl₂(cyclo-octa-1,5-diene)]₂ reacts with L to give [IrHCl₂L₃], which with chlorine gives mer-[IrCl₃L₃]. mer-[IrCl₃L₃] is converted by boiling 2-methoxyethanol into [IrCl₂(P–C)L₂] very rapidly. [IrCl(cyclo-octa-1,5-diene)]₂ reacts with L to give [IrHCl(P–C)L₂], which, in boiling 2-methoxyethanol, is converted to [IrCl(P-C)₂L]. The base-promoted metallations are readily reversed by HCl, e.g. [IrCl(P–C)₂L] gives [IrCl₂(P–C)L₂] and [IrHCl(P–C)L₂] gives [IrHCl₂L₃], etc. A few rhodium complexes were also prepared such as [RhCl₂(P–C)L₂] and [RhClL₃]. The configurations of these complexes were determined by ¹H and /or ³¹P n.m.r. spectroscopy. I.r. data are also recorded.