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[DPEPhosbcpCu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
Halogenation of the Hexaphosphabenzene Complex [(Cp*Mo)2 (μ,η6 :η6 -P6 )]: Snapshots on the Reaction Progress
Anna Garbagnati1, Michael Seidl1, Gábor Balázs1
1Institute of Inorganic Chemistry, University of Regensburg, 93040, Regensburg, Germany.
Abstract:
The oxidation of [(Cp*Mo)2 (μ,η6 :η6 -P6 )] (1) with halogens or halogen sources was investigated. The iodination afforded the ionic complexes [(Cp*Mo)2 (μ,η3 :η3 -P3 )(μ,η1 :η1 :η1 :η1 -P3 I3 )][X] (X=I3 - , I- ) (2) and [(Cp*Mo)2 (μ,η4 :η4 -P4 )(μ-PI2 )][I3 ] (3), while the reaction with PBr5 led to the complexes [(Cp*Mo)2 (μ,η3 :η3 -P3 )(μ-Br)2 ][Cp*MoBr4 ] (4) [(Cp*MoBr)2 (μ,η3 :η3 -P3 )(μ,η1 -P2 Br3 )] (5) and [(Cp*Mo)2 (μ-PBr2 )(μ-PHBr)(μ-Br)2 ] (6). The reaction of 1 with the far stronger oxidizing agent PCl5 was followed via time- and temperature-dependent 31 P{1 H} NMR spectroscopy. One of the first intermediates detected at 193 K was [(Cp*Mo)2 (μ,η3 :η3 -P3 )(μ-PCl2 )2 ][PCl6 ] (8) which rearranges upon warming to [(Cp*Mo)2 (μ-PCl2 )2 (μ-Cl)2 ] (9), [(Cp*MoCl)2 (μ,η3 :η3 -P3 )(μ-PCl2 )] (10) and [(Cp*Mo)2 (μ,η4 :η4 -P4 )(μ-PCl2 )][Cp*MoCl4 ] (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.
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