New iridium(I) complexes with labile ligands: Reactivity and structural characterization by atmospheric pressure mass and tandem mass spectrometry

Article abstract of DOI:10.1016/j.ica.2003.12.025

Reaction of diphosphine complexes [IrCl{(C₆F₅) ₂P(CH₂)₂P(C₆F₅) ₂}]₂ (I) and [IrCl(dppe)]₂ (II) with coordinating solvents (acetonitrile, acetone, DMSO) leads to several square-planar complexes of the type [IrCl(diphosphine)(solvent)] which are stable only in solution ([IrCl{(C₆F₅)₂P(CH ₂)₂P(C₆F₅)₂}(NCCH ₃)] (III) and [IrCl{(C₆F₅)₂P(CH ₂)₂P(C₆F₅)₂}(acetone)], IV) and/or can be detected only under APCI-MS/MS conditions ([IrCl(dppe) (solvent)]). When III is allowed to react with CO for at least 30 min, the unusual five coordinated trans-dicarbonyl complex [IrCl{(C₆F ₅)₂P(CH₂)₂P(C₆F ₅)₂}(CO)₂] (Vb) is formed, as characterized by ¹H and ³¹P NMR, FT-IR, TGA and APCI-MS/MS. A new and stable square-planar complex [Ir(OCH₃)(cod)(PClPh₂)] (IX) was also synthesized. Its APCI-MS/MS spectrum is simple and unique as it shows exclusively the loss of a neutral C₃H₂ species. Along with the APCI-MS and APCI-MS/MS analyses, whenever it was possible all complexes were also characterized by ¹H and ³¹P NMR spectroscopy.