Structure of (η-allyl)dicarbonyl(pentane-2,4-dionato)pyridine-molybdenum(II) in the solid and solution states

Structure and Dynamic Behavior of (η3-Allyl)bromodicarbonylmolybdenum(II) Complexes Containing Polydentate 2-Pyridylphosphanes or Their Oxides as Chelating Ligands: Occurrence of Three Fluxional Processes

“…The structure is shown in Figure 4, and Table 1 lists relevant distances and angles. The P-O distance is slightly elongated compared to those found in palladium(II) complexes containing the OPPy 2 Ph ligand, where the oxygen atom is not coordinated to the metal: P-O ϭ 1.480(2) and 1.482(2) Å in [Pd(C 6 F 5 )X(OPPy 2 Ph-N 2 )] (X ϭ Br and C 6 and angles of the allyl group found in 5 are very similar to those reported for [Mo(η 3 -allyl)(acac)(CO) 2 (py)], [18] which also contains an oxygen donor ligand and a nitrogen donor ligand in the equatorial positions. The two carbonyls and the allyl are mutually cis, with the terminal carbon atoms of the allyl moiety oriented over the carbonyls, as usually found for this class of complex.…”

Structure and Dynamic Behavior of (η3-Allyl)bromodicarbonylmolybdenum(II) Complexes Containing Polydentate 2-Pyridylphosphanes or Their Oxides as Chelating Ligands: Occurrence of Three Fluxional Processes

“…1.501(4) Å in 5. The donor atoms of the OPPy 3 ligand coordinated in the equatorial positions have different donor properties, but this seems to induce very little asymmetry in the trans carbonyl groups: the Mo-C distances are equal [1.934 (7) and angles of the allyl group found in 5 are very similar to those reported for [Mo(η 3 -allyl)(acac)(CO) 2 (py)], [18] which also contains an oxygen donor ligand and a nitrogen donor ligand in the equatorial positions.…”

Fluxional Processes in Diamagnetic and Paramagnetic Allyl Dicarbonyl and 2-Methylallyl Dicarbonyl Molybdenum Histidinato Complexes as Revealed by Spectroscopic Data and Density Functional Calculations

“…[34,35,39,40] Also, the activation barriers of interconversion are in the range reported for trigonal twists of other pseudooctahedral Mo(allyl)(CO) 2 compounds. [39,40] Unlike all previous examples with a higher symmetry, three different positions of the allyl ligand with respect to the Mo(His) plane are possible in 1 ± 4. Even in very clean 1 H NMR spectra we could not detect signals of a third isomer in solution.…”