[1,1′-Bis(diphenylphosphino)ferrocene]carbonyl[dihydrobis(pyrazol-1-yl)borato]hydridoruthenium(II) acetone solvate

In the title compound, [FeRu(C17H14P)2(C6H8BN4)H(CO)]·C3H6O, the RuII ion is coordinated in a distorted octahedral environment involving a hydride ligand, a carbonyl ligand and two bidentate ligands. Of the two bidentate ligands, the bulky 1,1′-bis(diphenylphosphino)ferrocene (dppf) ligand chelates with a larger bite angle of 101.90 (2)°, whereas the bite angle of the [H2Bpz2]− ligand (pz = pyrazolyl) is 85.67 (7)°. The latter ligand creates an RuN4B six-membered ring with a boat conformation, which puckers towards the site of the small hydride ligand. The hydride ligand is cis with respect to the carbonyl ligand and trans to one of the P atoms of the dppf ligand. In the crystal structure, there are weak intermolecular C—H⋯O hydrogen bonds between complex molecules and acetone solvent molecules.

In the title compound, [FeRu(C 17 H 14 P) 2 (C 6 H 8 BN 4 )H(CO)]Á-C 3 H 6 O, the Ru II ion is coordinated in a distorted octahedral environment involving a hydride ligand, a carbonyl ligand and two bidentate ligands. Of the two bidentate ligands, the bulky 1,1 0 -bis(diphenylphosphino)ferrocene (dppf) ligand chelates with a larger bite angle of 101.90 (2) , whereas the bite angle of the [H 2 Bpz 2 ] À ligand (pz = pyrazolyl) is 85.67 (7) . The latter ligand creates an RuN 4 B six-membered ring with a boat conformation, which puckers towards the site of the small hydride ligand. The hydride ligand is cis with respect to the carbonyl ligand and trans to one of the P atoms of the dppf ligand. In the crystal structure, there are weak intermolecular C-HÁ Á ÁO hydrogen bonds between complex molecules and acetone solvent molecules.
As the dihydrobis(pyrazol-1-yl)borate ligand usually occupies no more than two coordination sites of a transition metal ion, it may be advantageous to introduce additional chelate ligands to further control the electronic and steric factors of the Ru II complex (Huh et al., 1996). In this regard, we successfully prepared and characterized a new Ru II compound with two different bidentate ligands. A ligand displacement reaction of RuH(PPh 3 ) 2 (η 2 -H 2 Bpz 2 )(CO) by 1,1'bis(diphenylphosphino)ferrocene (dppf) yielded the title compound RuH(CO)(dppf)(η 2 -H 2 Bpz 2 ).CH 3 COCH 3 , (I), which contains two different bidentate ligands, a neutral dppf ligand with two P donor atoms and an anionic [H 2 Bpz 2 ]ligand with two N donor atoms. The two mutually trans-positioned PPh 3 ligands of the starting Ru II complex were successfully replaced by the dppf ligand.
The dppf ligand coordinates to the Ru II ion in the normal bidentate chelation mode as shown in Figure 1. The dppf ligand is bulkier than the [H 2 Bpz 2 ]ligand and hence the bite angle for the dppf ligand, P1-Ru1-P2, is 101.90 (2)°. This value is not significantly different from that in the known structure of [RuH(dppf)(NCCH 3 )(PPh 3 )(CO)] + , 102.15 (9)° (Han et al., 1996). The N1-Ru1-N3 bite angle is much smaller with a value of 85.67 (7)° A six-membered ring consisting of atoms of Ru1/N1-N4/B1 is in a boat conformation which is puckered towards the hydride ligand.
The longer Ru1-P2 bond (compared to Ru1-P1) may be attributed to the stronger trans effect of the hydride ligand than nitrogen donor atom of [H 2 Bpz 2 ] -. The overall coordination environment of Ru II ion is a distorted octahedral geometry.
The two cyclopentadienyl rings of the dppf ligand show a staggered geometry.

Refinement
H atoms bonded to C atoms were placed in calculated positions, with C-H = 0.95 -1.00 Å and were included in a ridingmodel approximation with U iso (H) = 1.2U eq (C) or 1.5U eq (C) for methyl H atoms. The positional parameters of the H atoms bonded to B1 were refined with U iso (H) = 1.2U eq (B), while the hydride H atom (H1) was refined independently with an isotropic displacement parameter. Fig. 1. The molecular structure of the title compound with 30% ellipsoids for non-hydrogen atoms. The solvent acetone molecule is not shown and H atoms bonded to C atoms have been omitted.