Ligand Sphere Conversions in Terminal Carbide Complexes
Thorbjørn
J. Morsing
Anders Reinholdt
Stephan P. A. Sauer
Jesper Bendix
10.1021/acs.organomet.5b00803.s002
https://acs.figshare.com/articles/dataset/Ligand_Sphere_Conversions_in_Terminal_Carbide_Complexes/2084308
Metathesis
is introduced as a preparative route to terminal carbide
complexes. The chloride ligands of the terminal carbide complex [RuC(Cl)<sub>2</sub>(PCy<sub>3</sub>)<sub>2</sub>] (<b>RuC</b>) can be exchanged,
paving the way for a systematic variation of the ligand sphere. A
series of substituted complexes, including the first example of a
cationic terminal carbide complex, [RuC(Cl)(CH<sub>3</sub>CN)(PCy<sub>3</sub>)<sub>2</sub>]<sup>+</sup>, is described and characterized
by NMR, MS, X-ray crystallography, and computational studies. The
experimentally observed irregular variation of the carbide <sup>13</sup>C chemical shift is shown to be accurately reproduced by DFT, which
also demonstrates that details of the coordination geometry affect
the carbide chemical shift equally as much as variations in the nature
of the auxiliary ligands. Furthermore, the kinetics of formation of
the sqaure pyramidal dicyano complex, <i>trans</i>-[RuC(CN)<sub>2</sub>(PCy<sub>3</sub>)<sub>2</sub>], from <b>RuC</b> has
been examined and the reaction found to be quite sluggish and of first
order in both <b>RuC</b> and cyanide with a rate constant of <i>k</i> = 0.0104(6) M<sup>–1</sup> s<sup>–1</sup>. Further reaction with cyanide
leads to loss of the carbide ligand and formation of <i>trans</i>-[Ru(CN)<sub>4</sub>(PCy<sub>3</sub>)<sub>2</sub>]<sup>2–</sup>, which was isolated and structurally characterized as its PPh<sub>4</sub><sup>+</sup> salt.
2016-01-25 00:00:00
RuC
Terminal Carbide ComplexesMetathesis
carbide 13 C chemical shift
Ligand Sphere Conversions
ligand sphere
carbide ligand
terminal carbide complexes
DFT
variation
carbide chemical shift
cationic terminal carbide
NMR
coordination geometry
terminal carbide
MS
chloride ligands