Unexpected formation of Cp* IrCl 2PPh 3 from the reaction of [Cp* Ir( η5-C 6H 5O)][BF 4] with PPh 3 in dichloroethane involving C-Cl bond activation

Abstract

The reaction of [Cp* Ir( η 5-C 6H 5O)][BF 4] ( 1) with PPh 3 in refluxing C 2H 4Cl 2 afforded unexpectedly but reproducibly the known compound Cp* IrCl 2PPh 3 ( 2) which was identified by 1H-NMR spectroscopy and single crystal X-ray diffraction. This unexpected chemical transformation to give 2 involves ‘C-Cl’ abstraction from dichloroethane mediated by the ‘Cp* Ir’ fragment. A rationale for this surprising transformation is advanced.