Halogenation of the Hexaphosphabenzene Complex [(Cp*Mo) (μ,η :η -P )]: Snapshots on the Reaction Progress.

The oxidation of [(Cp*Mo) (μ,η :η -P )] (1) with halogens or halogen sources was investigated. The iodination afforded the ionic complexes [(Cp*Mo) (μ,η :η -P )(μ,η :η :η :η -P I )][X] (X=I , I ) (2) and [(Cp*Mo) (μ,η :η -P )(μ-PI )][I ] (3), while the reaction with PBr led to the complexes [(Cp*Mo) (μ,η :η -P )(μ-Br) ][Cp*MoBr ] (4) [(Cp*MoBr) (μ,η :η -P )(μ,η -P Br )] (5) and [(Cp*Mo) (μ-PBr )(μ-PHBr)(μ-Br) ] (6). The reaction of 1 with the far stronger oxidizing agent PCl was followed via time- and temperature-dependent P{ H} NMR spectroscopy. One of the first intermediates detected at 193 K was [(Cp*Mo) (μ,η :η -P )(μ-PCl ) ][PCl ] (8) which rearranges upon warming to [(Cp*Mo) (μ-PCl ) (μ-Cl) ] (9), [(Cp*MoCl) (μ,η :η -P )(μ-PCl )] (10) and [(Cp*Mo) (μ,η :η -P )(μ-PCl )][Cp*MoCl ] (11), which could be isolated at room temperature. All complexes were characterized by single-crystal X-ray diffraction, NMR spectroscopy and their electronic structures were elucidated by DFT calculations.