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Updated: May 19, 2026

Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Investigations into the formation and stability of cationic rhodium diphosphane η6-arene complexes
Christian Fischer1, Richard Thede, Hans-Joachim Drexler
1Leibniz-Institut für Katalyse e.V. Albert-Einstein-Strasse 29a, 18059 Rostock, Germany.
Abstract:
Rhodium-η(6)-arene complexes can be generated in the presence of arenes following the hydrogenation of the diolefin in rhodium catalyst precursors of the type [Rh(PP*)(diolefin)]X (PP* = chelating diphosphane, X = noncoordinating anion). In this paper we report the characterization of such arene complexes with the ligands DuPhos, dipamp, dppe, Tangphos, dppf, and diop by means of NMR spectroscopy ((31)P, (103)Rh) and X-ray analysis. A procedure that follows the approach to equilibrium as a function of time monitored by using an UV/Vis diode array was used to determine 20 stability constants. Analyses were accomplished directly from the spectra by either a numeric and/or a new analytic solution of the underlying system of differential equations. Additionally thermodynamic parameters were determined in the temperature range between 278 and 318 K.
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