U. Meier, F. Hollmann, U. Thewalt
Aug 9, 2003
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0
Influential Citations
12
Citations
Journal
Organometallics
Abstract
Five new nonsymmetric 1-diphenylphosphino-3-{bis[aryl]phosphino}propane ligands 1b−f [aryl: b = 3,5-bis(trifluoromethyl)phenyl, c = 3,5-dimethylphenyl, d = 3,5-difluorophenyl, e = 2-(trifluoromethyl)phenyl, f = 2,4,6-trifluorophenyl] and their corresponding neutral dichloro palladium(II) 2b−f, diiodo palladium(II) 3d,e, and dicationic diacetonitrile palladium(II) ditetrafluoroborate complexes 4b−f were synthesized. The symmetric ligand 1,3-bis{bis[3,5-bis(trifluoromethyl)phenyl]phosphino}propane (1a) and the related palladium(II) complexes 2a and 4a were prepared for comparison. Solid state structures of new ligands were determined by X-ray structure analysis in the form of the dichloro (2a−c,f) and diiodo (3d,e) compounds. The properties of the symmetric (4a) and nonsymmetric catalysts (4b−f) were tested in propene/CO copolymerization experiments. A clear correlation between primarily steric effects of these ligands and the catalyst activity as well as the molecular weight of the resulting polyketone ma...