| Autor: |
Chalmers, Brian A., Nejman, Phillip S., Llewellyn, Alice V., Felaar, Adrian M., Griffiths, Ben L., Portman, Eden I., Gordon, Emma-Jane L., Fan, Kenny J. H., Woollins, J. Derek, Bühl, M., Malkina, Olga L., Cordes, David B., Slawin, Alexandra M. Z., Kilian, Petr |
| Zdroj: |
Inorganic Chemistry; March 2018, Vol. 57 Issue: 6 p3387-3398, 12p |
| Abstrakt: |
A series of representative late d-block metal complexes bearing a rigid bis(phosphine) ligand, iPr2P-Ace-PPh2(L, Ace = acenaphthene-5,6-diyl), was prepared and fully characterized by various techniques, including multinuclear NMR and single-crystal X-ray diffraction. The heteroleptic nature of the peri-substituted ligand Lallows for the direct observation of the JPPcouplings in the 31P{1H} NMR spectra. Magnitudes of JPPare correlated with the identity and geometry of the metal and the distortions of the ligand L. The forced overlap of the phosphine lone pairs due to the constraints imposed by the rigid acenaphthene skeleton in Lresults in a large 4JPPof 180 Hz. Sequestration of the lone pairs, either via oxidation of the phosphine or via metal chelation, results in distinct changes in the magnitude of JPP. For tetrahedral d10complexes ([LMCl2], M = Zn, Cd, Hg), the JPPis comparable to or larger than (193–309 Hz) that in free ligand L, although the P···P separation in these complexes is increased by ca. 0.4 Å (compare to free ligand L). The magnitude of JPPdiminishes to 26–117 Hz in square planar d8complexes ([LMX2], M = Ni, Pd, Pt; X = Cl, Br) and the octahedral Mo0complex ([LMo(CO)4], 33 Hz). Coupling deformation density calculations indicate the through-space interaction dominates in free L, while in metal complexes the main coupling pathway is via the metal atom. |
| Databáze: |
Supplemental Index |
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