150266-91-4Relevant academic research and scientific papers
Fluxional Behavior of Cationic cis-Bis(ether-phosphane)palladium(II) Complexes. - 31P-DNMR Spectroscopic Investigations, Line-Shape Analysis, and Determination of Rearrangement Barriers
Lindner, Ekkehard,Dettinger, Johannes,Mayer, Hermann August,Kuehbauch, Hartwig,Fawzi, Riad,Steimann, Manfred
, p. 1317 - 1324 (2007/10/02)
Reaction of X2Pd(PO)2 (X = Cl: 1a-g, k-n, p; X = Br: l'; X = I: k'', l'', o'') with stoichiometric amounts of AgClO4 results in the formation of the monochelate complexes cis-O)(PO)> (2a-g, k-n, p, l', l'') (PO: η1-P-coordinated; PO: η2-O,P-chelated).In the case of compounds 1o, 1k'', and 1o'', which are provided with less basic ether-phosphanes, the halide-bridged dimers O)2>22 (3o, k'', o'') are obtained.Temperature-dependent 31P-NMR spectra of the fluxional complexes 2a-g, k-n, p, l', l'' lead to ΔG(excit.)values.By using modified versions of DNMR5, computer-generated spectra of 2a, b, f, k, l, p, l', l'' were obtained and fitted to the experimental spectra.Graphic application of the Eyring equation to the kinetic data afforded the thermodynaic parameters ΔH(excit.), ΔS(excit.), and ΔG(excit.).The ΔS(excit.) values are in agreement with an associative exchange mechanism for 2a, b, f, l, p, l', l'' and with a dissociative exchange mechanism for 2k. 2k and 3o crystallize in the monoclinic and triclinic space group P21/c and P with Z = 4 and Z = 2, respectively.Key Words: Palladium complexes / Ether-phosphanes / NMR, 31P, dynamic, line-shape analysis / Fluxional behavior
