Carbonylbis(triphenylphosphane-κP)(η2-1-vinylpyrrolidin-2-one-κO)ruthenium(0)

The 1-vinylpyrrolidin-2-one ligand in the title compound, [Ru(C6H9NO)(C18H15P)2(CO)], coordinates to the Ru0 atom with the olefin double bond and the ketone O atom. The Ru0 atom adopts a distorted trigonal–bipyramidal coordination geometry, with the C O ligand and the ketone O atom occupying the axial positions. The two triphenylphosphane ligands are cis to each other. The olefinic C=C bond is almost coplanar with the Ru0 atom and the two P atoms (maximum deviation of 0.0516 Å from the mean plane defined by the five constituent atoms). The coordinated C=C bond has a length of 1.449 (3) Å, which is significantly longer than that of a free C=C bond (1.34 Å). There are two C—H⋯π interactions involving neighbouring phenyl rings in the molecule. In the crystal, molecules are linked via two further C—H⋯π interactions.

The 1-vinylpyrrolidin-2-one ligand in the title compound, [Ru(C 6 H 9 NO)(C 18 H 15 P) 2 (CO)], coordinates to the Ru 0 atom with the olefin double bond and the ketone O atom. The Ru 0 atom adopts a distorted trigonal-bipyramidal coordination geometry, with the C O ligand and the ketone O atom occupying the axial positions. The two triphenylphosphane ligands are cis to each other. The olefinic C C bond is almost coplanar with the Ru 0 atom and the two P atoms (maximum deviation of 0.0516 Å from the mean plane defined by the five constituent atoms). The coordinated C C bond has a length of 1.449 (3) Å , which is significantly longer than that of a free C C bond (1.34 Å ). There are two C-HÁ Á Á interactions involving neighbouring phenyl rings in the molecule. In the crystal, molecules are linked via two further C-HÁ Á Á interactions.

Si Jia Ma and Po Niu Comment
Ortho-alkylation of acetophenone with vinyl silanes via ruthenium catalyzed C-H activation has been reported by (Murai et al., 1993) Cylometallation of the aromatic ketone with the catalytically active ruthenium(0) species, Ru(CO) (PPh 3 ) 3 , generated from dehydrogenation of RuH 2 (CO)(PPh 3 ) 3 , is proposed as the key step (Murai et al., 1993). On exploring the feasibility of cyclometallation of N-vinyl-2-pyrrolidone with the ruthenium hydride complex RuH 2 (CO) (PPh 3 ) 3 , the title compound was obtained instead of the cyclometallated product.
The molecular structure of the title compound is illustrated in Fig. 1. The N-Vinyl-2-pyrrolidone ligand is bound to the ruthenium(0) center via the olefin double bond (C6═C7) and the ketone O atom (O2). The ruthenium (0)  There are two C-H···π interactions involving neighbouring phenyl rings in the molecule, and in the crystal, molecules are linked via two further C-H···π interactions (Table 1).

Experimental
To a solution of RuH 2 (CO)(PPh 3 ) 3 (0.40 g, 0.44 mmol) in toluene (20 ml) and under a nitrogen atmosphere was added Nvinyl-2-pyrrolidone (0.40 ml, 3.6 mmol). The reaction mixture was then refluxed for 1 h to give a yellow solution. After filtration, the filtrate was concentrated to ca. 1 ml under reduced pressure. 20 ml n-hexane were added to the residue with stirring to give a yellow solid. The solid was collected by filtration, washed with n-hexane and diethyl ether, and dried under vacuum [Yield: 0.24 g, 72%]. Yellow block-like crystals, suitable for X-ray analysis, were obtained by layering a dichloromethane solution of the title compound with hexane.

Refinement
The H atoms were included in calculated positions and treated as rding atoms: C-H = 0.95, 0.99, 0.99 and 1.00 Å for phenyl, pyrrolidone, CH 2 and CH H atoms, respectively, with U iso (H) = k × U eq (C), where k = 1.5 for pyrrolidone H supplementary materials sup-2 . E68, m608 atoms, and = 1.2 for other H atoms. In the final difference Fourier map the highest and lowest residual electron density peaks were 0.94 and 0.92 Å, respectively, from atom Ru1.

Figure 1
The molecular structure of the title compound with the atom-labelling. The displacement ellipsoids are drawn at the 40% probability level displacement ellipsoids (H atoms have been omitted for clarity).

Carbonylbis(triphenylphosphane-κP)(η 2 -1-vinylpyrrolidin-2-one-κO)ruthenium(0)
Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. 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 > σ(F 2 ) is used only for calculating R-factors(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.