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Updated: Jun 17, 2026
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Single-crystal XRD characterization, physicochemical properties and catalytic activity of rhodium(III/IV)
Kacper Pobłocki1,2, Marzena Białek2, Katarzyna N Jarzembska3
1Department of Environmental Technology, University of Gdansk, Faculty of Chemistry, 63 Wita Stwosza, 80-308 Gdansk, Poland. kacper.poblocki@phdstud.ug.edu.pl.
Abstract:
Two novel rhodium(III) and rhodium(IV) coordination compounds incorporating dipicolinate anion, 1,10-phenanthroline, and 2-phenylpyridine are presented. The crystal structure of the compounds was confirmed by single-crystal X-ray diffraction (XRD). Their physicochemical properties were investigated by potentiometric and conductometric titrations. Stability constants were determined using Hyperquad fitting analyses. In addition, the newly synthesized complexes were used as precatalysts for the polymerization of ethylene and the copolymerization of ethylene with α-olefins and methyl acrylate. Moderate catalytic activities of up to 3.13 × 105 gPE molRh-1 h-1 were achieved. The addition of comonomers reduces the catalytic activity but allows for control over the copolymer's microstructure and properties. These results establish clear structure-activity relationships in the (co)polymerization of olefins process.
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