Dichlorido(η6-p-cymene)(4-fluoroaniline-κN)ruthenium(II)

The title compound, [RuCl2(C10H14)(C6H6FN)], a pseudo-octahedral d 6 complex, has the expected piano-stool geometry around the Ru(II) atom. The fluoroaniline ring forms a dihedral angle of 19.3 (2)° with the p-cymene ring. In the crystal, two molecules form an inversion dimer via a pair of N—H⋯Cl hydrogen bonds. Weak intermolecular C—H⋯Cl interactions involving the p-cymene ring consolidate the crystal packing.

The title compound, [RuCl 2 (C 10 H 14 )(C 6 H 6 FN)], a pseudooctahedral d 6 complex, has the expected piano-stool geometry around the Ru(II) atom. The fluoroaniline ring forms a dihedral angle of 19.3 (2) with the p-cymene ring. In the crystal, two molecules form an inversion dimer via a pair of N-HÁ Á ÁCl hydrogen bonds. Weak intermolecular C-HÁ Á ÁCl interactions involving the p-cymene ring consolidate the crystal packing.
Our interest in studying relative binding affinities of soft metal centers for ligands of moderate and weak donor power using 19 F and 31 P NMR spectroscopy (Hoffman et al., 2009;Carter et al., 2004) to monitor ligand-substitution equilibria led us to prepare the title complex. Single crystals were grown from vapor diffusion of heptane into a benzene solution of the 4-fluoroaniline complex. The nitrogen atom in the 4-fluoroaniline ligand is essentially coplanar with its aromatic ring, whose plane is oriented slightly down and away from the plane of the p-cymene ring. Structural parameters were similar to those reported for the other (η 6 -p-cymene)Ru(4-X-C 6 H 4 NH 2 )Cl 2 piano-stool complexes above. The Ru-Cl, Ru-N, and Ru-C distances are quite ordinary. Somewhat greater differences exist between structural parameters of interest in the 4-fluoroaniline complexes of the divalent Pd and Ni moieties, likely because of their dissimilar combinations of d n configurations, coordination geometry, and ligand sets.
Dripped slowly into the resulting dark-orange solution with stirring were 2.0 ml methyl tert-butyl ether and then 50 ml heptane. The yellow-orange crystals afforded were filtered and washed with two 5-ml portions of hexanes and air-dried (88% yield).
NMR analysis of this product in CDCl 3 (Cambridge Laboratories) showed the following signals. Suitable single crystals were grown from vapor diffusion of 30 ml heptane into a benzene solution of the 4-fluoroaniline complex (25 mg in 5 ml) over six days at room temperature. Traces of remaining liquid were removed by disposable glass pipet from the resulting red crystals which were washed twice with 5.0 ml hexanes and air-dried overnight in the dark.

Refinement
Hydrogen atoms were placed in calculated positions and allowed to ride during subsequent refinement, with U iso (H) = 1.2U eq (C) and C-H distances of 0.93 Å for the aromatic H atoms, U iso (H) = 1.5U eq (C) and C-H distances of 0.96 Å for the methyl H atoms, U iso (H) = 1.2U eq (C) and a C-H distance of 0.98 Å for the methine H atom, and U iso (H) = 1.2U eq (N) and N-H distances of 0.90 Å for the amine H atoms.  Amounts of (η 6 -p-cymene)Ru(4-F-C 6 H 4 NH 2 )Cl 2 and P(O-2,4-Bu t 2 -C 6 H 3 ) 3 in CDCl 3 at 23 °C. supplementary materials sup-3
Dichlorido(η 6 -p-cymene)(4-fluoroaniline-κN)ruthenium(II) Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å 2 )
x y z U iso */U eq