metal-organic compounds
cis-Dichlorido(1,3-dimesitylimidazolidin-2-ylidene)(2-formylbenzylidene-κ2C,O)ruthenium diethyl ether solvate
aInstitute for Chemistry and Technology of Materials (ICTM), Graz University of Technology, Stremayrgasse 16, A-8010 Graz, Austria, and bInstitute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/164SC, A-1060 Vienna, Austria
*Correspondence e-mail: kurt.mereiter@tuwien.ac.at
The title compound, [RuCl2(C8H6O)(C21H26N2)]·C4H10O, contains a catalytically active ruthenium carbene complex of the `second-generation Grubbs/Hoveyda' type with Ru in a square-pyramidal coordination, the apex of which is formed by the benzylidene carbene atom with Ru=C 1.827 (2) Å. The complex shows the uncommon cis, rather than the usual trans, arrangement of the two chloride ligands, with Ru—Cl bond lengths of 2.3548 (6) and 2.3600 (6) Å, and a Cl—Ru—Cl angle of 89.76 (2)°. This cis configuration is desirable for certain applications of ring-opening metathesis polymerization (ROMP) of strained cyclic The crystalline solid is a diethyl ether solvate, which is built up from a porous framework of Ru complexes held together by π–π stacking and C—H⋯Cl and C—H⋯O interactions. The disordered diethyl ether solvent molecules are contained in two independent infinite channels, which extend parallel to the c axis at x,y = 0,0 and x,y = , and have solvent-accessible void volumes of 695 and 464 Å3 per unit cell.
Related literature
For the synthesis and application of the title compound in ring-opening metathesis polymerization (ROMP), see: Slugovc et al. (2004); Burtscher et al. (2006). For thermally switchable initiators for olefin metathesis polymerization, see: Gstrein et al. (2007); Szadkowska & Grela (2008). For a recent authoritative review on ruthenium-based heterocyclic carbene-coordinated olefin metathesis catalysts, see: Vougioukalakis & Grubbs (2010).
Experimental
Crystal data
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Data collection: SMART (Bruker, 2003); cell SAINT (Bruker, 2003); data reduction: SAINT, SADABS and XPREP (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004), PLATON and publCIF (Westrip, 2010).
Supporting information
https://doi.org/10.1107/S1600536810000826/bt5164sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810000826/bt5164Isup2.hkl
The title compound was synthesized as described by Slugovc et al. (2004). It was then dissolved in a small amount of CHCl3 and crystallized at room temperature by the vapour diffusion method using diethyl ether as the anti-solvent. Small green prismatic crystals were obtained, which remained stable at room temperature under oil for at least one hour. They were accompanied by some larger green crystals of different morphology, which after removal from the mother liquor crumbled by solvent loss within minutes and were probably a CHCl3 containing solvate.
All H atoms were placed in calculated positions and thereafter treated as riding. A torsional parameter was refined for each methyl group. Uiso(H) = 1.2Ueq(Cnon-methyl) and Uiso(H) = 1.5Ueq(Cmethyl) were used. The diethyl ether solvent molecules, which reside in two different infinite channels extending about the 4 axes parallel to the c-axis were disordered. The presence of CHCl3 was ruled out because solvent Fourier peaks did not exceed 2.2 e Å-3 in height. The solvent was initially approximated by 10 partly occupied carbon positions, which indicated the presence of about 4.7 diethyl ether molecules per in the larger and about 3.2 molecules per in the smaller channel. The solvent accessible void volumes of the two channels were 695 and 464 Å3 per (program PLATON; Spek, 2009). In the final the solvent peaks were omitted and the contribution of the solvent to the structure factors was removed with procedure SQUEEZE of program PLATON (version-250809; Spek, 2009). Chemical formula and quantities derived thereof are given in the crystal data for an idealized solvent content of 1 molecule of diethyl ether per formula unit.
The ruthenium complex RuCl2(C8H6O)(C21H26N2), which is the main constituent of the title compound, (I), was prepared by a carbene exchange reaction of (H2IMes)(pyridine)2(Cl)2RuCHPh (1eq.; H2IMes = 1,3-bismesityl-4,5-dihydroimidazol-2-ylidene) with 2-vinylbenzaldehyde (2 eq.) in CH2Cl2 at room temperature (Slugovc et al., 2004). In sharp contrast to most of the ruthenium carbene complexes bearing two halides and neutral donor co-ligands (phosphines or N-heterocyclic carbenes), which exhibit a trans stereochemistry of the two halide ligands, the ruthenium complex of the title compound bears them in a cis-disposition of a square pyramidal coordination about Ru, the apex of which is formed by the benzylidene carbon C41 with a characteristically short Ru—C bond of 1.827 (2) Å whereas the bond to the N-heterocyclic carbene carbon C11 is longer by 0.077 Å (Fig. 1 and Table 1). It has been shown, that cis-isomer is thermodynamically favoured over its trans-dichlorido counterpart (Slugovc et al., 2004). Ruthenium carbene complexes bearing a cis-dichlorido arrangement are particularly interesting, because they exhibit distinctly lower initiation rates in ring opening metathesis polymerization (ROMP) of strained cyclic
when compared to their trans-dichlorido counterparts (Gstrein et al., 2007). This feature is used to design latent ROMP initiators and catalysts for e.g. ring closing metathesis at elevated temperatures (Szadkowska & Grela, 2008; Burtscher et al., 2006; Vougioukalakis & Grubbs, 2010).A view of the Ru complex in the title compound is presented in Fig. 1. Bond lengths and angles about Ru (Table 1) are in good agreement with the bis-dichloromethane solvate of the same complex, RuCl2(C8H6O)(C21H26N2).2CH2Cl2, which crystallizes in a moclinic lattice, β = 108.181 (1)°, V = 3469.1 (3) Å3, Z = 4 (Slugovc et al., 2004). Both complexes, in (I) and in the dichloromethane solvate, show similar conformations and are stabilized by significant intramolecular π-π stacking interactions between the 2-formylbenzylidene and the adjacent mesityl moiety with the shortest intramolecular π-π contacts of C41···C21 = 3.00 Å, C42···C22 = 3.40 Å, and C43···C24 = 3.45 Å in (I) and 2.99, 3.42, and 3.43 Å in the dichloromethane solvate. Moreover, both complexes show intramolecular C—H···O,Cl interactions, e.g. in (I) between C37 and Cl1 and and C29 and Cl1 (Fig. 1 and Table 2). In contrast to the dichloromethane solvate, where the Ru complexes do not show any intermolecular π-π-stacking but are held together mainly by C—H···π and C—H···Cl intercations, intermolecular π-π-stacking is an important factor in the of (I). Fig. 2 demonstrates that the structure of (I) contains columnar stacks of molecules extending along the c-axis and showing intermolecular π-π-stacking between the formylbenzylidene and one of the two mesityl groups [corresponding π-π-contacts are C44···C33(x,1 - y,-1/2 + z) = 3.59 Å and C43···C32(x,1 - y,-1/2 + z) = 3.81 Å]. Further π-π-stacking interactions arise from the mutual indentation of these stacks [corresponding π-π-contacts are C22···C24(y,x,1/2 - z) = 3.82 Å, C23···C23(y,x,1/2 - z) = 3.64 Å and C24···C22(y,x,1/2 - z) = 3.82 Å]. Finally, the Ru-complexes are also held together by a larger number of weak intermolecular C—H···Cl,O interactions (Table 2). The result of all these interactions between the Ru complexes in (I) is a framework-like structure of tetragonal symmetry containing continuous channels which extend along the c-axis and contain the diethyl ether solvent molecules. As shown in Fig. 3, there are two different kinds of continuous channels in the this framework, both coinciding with the two crystallographically different sets of 4 axes of the lattice. The larger channel in this framework is centered at x,y = 0,0 and has a minimal net-diameter in the (001)-projection of 5.6 Å and a solvent-accessible volume per of 695 Å3 (program PLATON; Spek, 2009). The smaller channel is centered at x,y = 1/2,1/2, has in the projection a minimal net-diameter of 4.2 Å and a solvent-accessible volume per of 464 Å3. As described in the experimental section, the diethyl ether solvent molecules inside these channels are disordered with about 5 molecules per in the large and about 3 molecules per in the small channel.
P21/c, a = 12.1933 (6), b = 15.4520 (7), c = 19.3799 (9) Å,For the synthesis and application of the title compound in ring-opening metathesis polymerization (ROMP), see: Slugovc et al. (2004); Burtscher et al. (2006). For thermally switchable initiators for olefin metathesis polymerization, see: Gstrein et al. (2007); Szadkowska & Grela (2008). For a recent authoritative review on ruthenium-based heterocyclic carbene-coordinated olefin metathesis catalysts, see: Vougioukalakis & Grubbs (2010).
Data collection: SMART (Bruker, 2003); cell
SAINT (Bruker, 2003); data reduction: SAINT, SADABS and XPREP (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).Fig. 1. The structure of (I) with displacement ellipsoids for the non-hydrogen atoms drawn at the 50% probability level. | |
Fig. 2. Packing diagram of (I) viewed along the b-axis. The Ru complexes in the center are shown in space-filling representation in order to emphasize their column-like stacking along the c-axis and part of their π-π stacking interactions. | |
Fig. 3. Packing diagram of (I) viewed down the c-axis showing the two different kinds of channels which are occupied by disordered diethyl ether molecules. |
[RuCl2(C8H6O)(C21H26N2)]·C4H10O | Dx = 1.443 Mg m−3 |
Mr = 670.66 | Mo Kα radiation, λ = 0.71073 Å |
Tetragonal, P4c2 | Cell parameters from 8875 reflections |
a = 19.8603 (4) Å | θ = 2.3–29.6° |
c = 15.6582 (7) Å | µ = 0.71 mm−1 |
V = 6176.1 (3) Å3 | T = 100 K |
Z = 8 | Prism, green |
F(000) = 2784 | 0.43 × 0.25 × 0.22 mm |
Bruker SMART APEX CCD diffractometer | 8992 independent reflections |
Radiation source: normal-focus sealed tube | 7306 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.058 |
φ and ω scans | θmax = 30.0°, θmin = 2.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | h = −27→27 |
Tmin = 0.78, Tmax = 0.86 | k = −27→27 |
90504 measured reflections | l = −21→21 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.029 | H-atom parameters constrained |
wR(F2) = 0.067 | w = 1/[σ2(Fo2) + (0.0309P)2 + 1.9302P] where P = (Fo2 + 2Fc2)/3 |
S = 1.01 | (Δ/σ)max = 0.001 |
8992 reflections | Δρmax = 0.42 e Å−3 |
322 parameters | Δρmin = −0.31 e Å−3 |
0 restraints | Absolute structure: Flack (1983), 4175 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.02 (2) |
[RuCl2(C8H6O)(C21H26N2)]·C4H10O | Z = 8 |
Mr = 670.66 | Mo Kα radiation |
Tetragonal, P4c2 | µ = 0.71 mm−1 |
a = 19.8603 (4) Å | T = 100 K |
c = 15.6582 (7) Å | 0.43 × 0.25 × 0.22 mm |
V = 6176.1 (3) Å3 |
Bruker SMART APEX CCD diffractometer | 8992 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | 7306 reflections with I > 2σ(I) |
Tmin = 0.78, Tmax = 0.86 | Rint = 0.058 |
90504 measured reflections |
R[F2 > 2σ(F2)] = 0.029 | H-atom parameters constrained |
wR(F2) = 0.067 | Δρmax = 0.42 e Å−3 |
S = 1.01 | Δρmin = −0.31 e Å−3 |
8992 reflections | Absolute structure: Flack (1983), 4175 Friedel pairs |
322 parameters | Absolute structure parameter: −0.02 (2) |
0 restraints |
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 F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Ru | 0.163541 (9) | 0.497964 (9) | 0.046582 (10) | 0.02129 (4) | |
Cl1 | 0.27041 (3) | 0.53239 (3) | −0.00175 (4) | 0.02852 (11) | |
Cl2 | 0.11254 (3) | 0.57173 (3) | −0.05230 (4) | 0.03066 (12) | |
C11 | 0.20523 (12) | 0.48129 (11) | 0.16118 (14) | 0.0236 (5) | |
N12 | 0.23047 (10) | 0.42655 (10) | 0.19933 (12) | 0.0262 (4) | |
C13 | 0.25911 (14) | 0.44070 (13) | 0.28464 (16) | 0.0346 (6) | |
H13A | 0.3083 | 0.4328 | 0.2854 | 0.042* | |
H13B | 0.2376 | 0.4125 | 0.3291 | 0.042* | |
C14 | 0.24273 (15) | 0.51526 (12) | 0.29779 (18) | 0.0345 (6) | |
H14A | 0.2094 | 0.5216 | 0.3442 | 0.041* | |
H14B | 0.2838 | 0.5415 | 0.3111 | 0.041* | |
N15 | 0.21431 (10) | 0.53461 (9) | 0.21391 (12) | 0.0262 (4) | |
C21 | 0.23113 (12) | 0.35894 (11) | 0.16561 (14) | 0.0253 (5) | |
C22 | 0.17748 (12) | 0.31643 (12) | 0.18503 (14) | 0.0269 (5) | |
C23 | 0.17985 (12) | 0.25113 (12) | 0.15293 (15) | 0.0288 (5) | |
H23 | 0.1435 | 0.2214 | 0.1646 | 0.035* | |
C24 | 0.23375 (13) | 0.22794 (12) | 0.10419 (16) | 0.0302 (5) | |
C25 | 0.28701 (12) | 0.27169 (12) | 0.08777 (16) | 0.0296 (5) | |
H25 | 0.3243 | 0.2562 | 0.0553 | 0.035* | |
C26 | 0.28676 (12) | 0.33789 (12) | 0.11807 (15) | 0.0285 (5) | |
C27 | 0.11903 (14) | 0.33958 (13) | 0.23832 (17) | 0.0348 (6) | |
H27A | 0.1354 | 0.3547 | 0.2941 | 0.052* | |
H27B | 0.0874 | 0.3022 | 0.2462 | 0.052* | |
H27C | 0.0962 | 0.3769 | 0.2094 | 0.052* | |
C28 | 0.23392 (14) | 0.15699 (12) | 0.06930 (18) | 0.0359 (6) | |
H28A | 0.2786 | 0.1464 | 0.0464 | 0.054* | |
H28B | 0.2004 | 0.1532 | 0.0237 | 0.054* | |
H28C | 0.2229 | 0.1253 | 0.1152 | 0.054* | |
C29 | 0.34414 (13) | 0.38489 (13) | 0.09885 (18) | 0.0350 (6) | |
H29A | 0.3799 | 0.3602 | 0.0691 | 0.052* | |
H29B | 0.3619 | 0.4033 | 0.1524 | 0.052* | |
H29C | 0.3281 | 0.4218 | 0.0626 | 0.052* | |
C31 | 0.18137 (13) | 0.59830 (11) | 0.20283 (15) | 0.0275 (5) | |
C32 | 0.11424 (13) | 0.60492 (12) | 0.22833 (15) | 0.0303 (5) | |
C33 | 0.08306 (13) | 0.66723 (13) | 0.21854 (17) | 0.0339 (6) | |
H33 | 0.0371 | 0.6719 | 0.2344 | 0.041* | |
C34 | 0.11702 (15) | 0.72254 (13) | 0.18645 (17) | 0.0355 (6) | |
C35 | 0.18389 (14) | 0.71537 (13) | 0.16534 (17) | 0.0361 (6) | |
H35 | 0.2076 | 0.7535 | 0.1447 | 0.043* | |
C36 | 0.21842 (14) | 0.65417 (13) | 0.17305 (16) | 0.0317 (5) | |
C37 | 0.07556 (14) | 0.54747 (13) | 0.26922 (17) | 0.0359 (6) | |
H37A | 0.0719 | 0.5101 | 0.2286 | 0.054* | |
H37B | 0.0304 | 0.5630 | 0.2849 | 0.054* | |
H37C | 0.0994 | 0.5322 | 0.3205 | 0.054* | |
C38 | 0.08123 (17) | 0.78913 (15) | 0.1766 (2) | 0.0498 (8) | |
H38A | 0.1139 | 0.8259 | 0.1818 | 0.075* | |
H38B | 0.0470 | 0.7936 | 0.2213 | 0.075* | |
H38C | 0.0596 | 0.7911 | 0.1204 | 0.075* | |
C39 | 0.29151 (14) | 0.64977 (14) | 0.15142 (18) | 0.0384 (6) | |
H39A | 0.3106 | 0.6089 | 0.1767 | 0.058* | |
H39B | 0.3150 | 0.6893 | 0.1741 | 0.058* | |
H39C | 0.2969 | 0.6482 | 0.0892 | 0.058* | |
C41 | 0.17781 (11) | 0.41460 (11) | 0.00063 (15) | 0.0247 (4) | |
H41 | 0.2229 | 0.4046 | −0.0152 | 0.030* | |
C42 | 0.12846 (11) | 0.36162 (11) | −0.01471 (14) | 0.0237 (4) | |
C43 | 0.14811 (12) | 0.30477 (12) | −0.06108 (16) | 0.0291 (5) | |
H43 | 0.1929 | 0.3017 | −0.0820 | 0.035* | |
C44 | 0.10326 (13) | 0.25294 (13) | −0.07703 (17) | 0.0349 (6) | |
H44 | 0.1178 | 0.2150 | −0.1091 | 0.042* | |
C45 | 0.03799 (13) | 0.25513 (12) | −0.0475 (2) | 0.0382 (6) | |
H45 | 0.0079 | 0.2189 | −0.0584 | 0.046* | |
C46 | 0.01669 (12) | 0.31127 (12) | −0.00132 (19) | 0.0329 (5) | |
H46 | −0.0283 | 0.3135 | 0.0191 | 0.039* | |
C47 | 0.06097 (12) | 0.36413 (11) | 0.01500 (15) | 0.0254 (5) | |
C48 | 0.03578 (12) | 0.42013 (11) | 0.06446 (14) | 0.0256 (5) | |
H48 | −0.0097 | 0.4179 | 0.0830 | 0.031* | |
O49 | 0.06864 (8) | 0.47089 (8) | 0.08469 (10) | 0.0247 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ru | 0.02463 (9) | 0.01835 (8) | 0.02089 (6) | 0.00016 (7) | −0.00329 (7) | 0.00037 (7) |
Cl1 | 0.0282 (3) | 0.0274 (3) | 0.0299 (3) | −0.0055 (2) | −0.0025 (2) | 0.0014 (2) |
Cl2 | 0.0356 (3) | 0.0285 (3) | 0.0279 (2) | 0.0077 (2) | −0.0004 (2) | 0.0049 (2) |
C11 | 0.0246 (11) | 0.0228 (10) | 0.0234 (11) | −0.0010 (8) | −0.0020 (8) | 0.0002 (8) |
N12 | 0.0320 (10) | 0.0237 (10) | 0.0230 (8) | 0.0054 (8) | −0.0083 (8) | −0.0013 (8) |
C13 | 0.0451 (15) | 0.0300 (13) | 0.0288 (13) | 0.0075 (11) | −0.0136 (11) | −0.0045 (10) |
C14 | 0.0486 (16) | 0.0283 (14) | 0.0265 (11) | 0.0037 (10) | −0.0150 (12) | −0.0027 (11) |
N15 | 0.0354 (11) | 0.0215 (10) | 0.0218 (9) | −0.0018 (8) | −0.0085 (8) | −0.0018 (7) |
C21 | 0.0306 (12) | 0.0206 (11) | 0.0248 (11) | 0.0079 (9) | −0.0075 (9) | −0.0015 (9) |
C22 | 0.0309 (12) | 0.0255 (11) | 0.0243 (11) | 0.0063 (10) | −0.0056 (9) | 0.0027 (9) |
C23 | 0.0302 (12) | 0.0252 (12) | 0.0309 (12) | 0.0012 (10) | −0.0049 (10) | 0.0026 (9) |
C24 | 0.0339 (13) | 0.0264 (12) | 0.0301 (12) | 0.0075 (10) | −0.0114 (10) | −0.0025 (10) |
C25 | 0.0271 (12) | 0.0280 (12) | 0.0336 (13) | 0.0081 (10) | −0.0057 (10) | −0.0046 (10) |
C26 | 0.0256 (12) | 0.0297 (12) | 0.0304 (12) | 0.0064 (9) | −0.0070 (9) | 0.0008 (10) |
C27 | 0.0401 (15) | 0.0304 (14) | 0.0341 (13) | 0.0037 (11) | 0.0033 (11) | 0.0010 (10) |
C28 | 0.0401 (15) | 0.0213 (12) | 0.0463 (15) | 0.0069 (10) | −0.0076 (12) | −0.0069 (10) |
C29 | 0.0273 (13) | 0.0310 (13) | 0.0466 (15) | 0.0039 (10) | −0.0056 (11) | −0.0010 (12) |
C31 | 0.0368 (13) | 0.0207 (10) | 0.0251 (10) | −0.0017 (9) | −0.0081 (10) | −0.0005 (9) |
C32 | 0.0367 (14) | 0.0260 (12) | 0.0282 (12) | −0.0048 (10) | −0.0084 (10) | −0.0026 (9) |
C33 | 0.0305 (13) | 0.0312 (13) | 0.0400 (15) | 0.0000 (10) | −0.0047 (11) | −0.0042 (11) |
C34 | 0.0450 (16) | 0.0234 (12) | 0.0381 (14) | 0.0018 (11) | −0.0060 (12) | −0.0022 (10) |
C35 | 0.0461 (16) | 0.0215 (12) | 0.0406 (14) | −0.0065 (11) | −0.0035 (12) | 0.0008 (10) |
C36 | 0.0393 (14) | 0.0267 (12) | 0.0290 (12) | −0.0050 (11) | −0.0072 (11) | −0.0034 (10) |
C37 | 0.0401 (15) | 0.0320 (14) | 0.0356 (13) | −0.0036 (12) | 0.0013 (11) | −0.0002 (11) |
C38 | 0.0548 (19) | 0.0303 (15) | 0.064 (2) | 0.0097 (13) | 0.0022 (16) | 0.0049 (14) |
C39 | 0.0403 (15) | 0.0334 (14) | 0.0416 (14) | −0.0077 (11) | −0.0017 (12) | −0.0058 (11) |
C41 | 0.0244 (10) | 0.0235 (10) | 0.0261 (11) | 0.0015 (8) | −0.0037 (9) | 0.0015 (9) |
C42 | 0.0253 (11) | 0.0220 (10) | 0.0238 (10) | −0.0001 (9) | −0.0036 (8) | 0.0035 (8) |
C43 | 0.0281 (11) | 0.0271 (12) | 0.0320 (12) | 0.0035 (9) | −0.0020 (10) | −0.0044 (10) |
C44 | 0.0342 (14) | 0.0253 (12) | 0.0453 (14) | 0.0042 (10) | −0.0057 (11) | −0.0082 (10) |
C45 | 0.0324 (13) | 0.0256 (12) | 0.0566 (16) | −0.0024 (10) | −0.0102 (14) | −0.0079 (12) |
C46 | 0.0271 (12) | 0.0255 (12) | 0.0461 (13) | −0.0006 (9) | −0.0040 (11) | −0.0006 (11) |
C47 | 0.0272 (11) | 0.0201 (10) | 0.0289 (11) | 0.0025 (8) | −0.0027 (9) | 0.0024 (9) |
C48 | 0.0240 (11) | 0.0246 (11) | 0.0282 (12) | 0.0025 (9) | 0.0000 (9) | 0.0016 (9) |
O49 | 0.0252 (8) | 0.0219 (8) | 0.0271 (8) | 0.0016 (6) | −0.0018 (6) | 0.0005 (6) |
Ru—C41 | 1.827 (2) | C31—C32 | 1.398 (4) |
Ru—C11 | 2.004 (2) | C31—C36 | 1.411 (3) |
Ru—O49 | 2.0487 (16) | C32—C33 | 1.392 (3) |
Ru—Cl1 | 2.3548 (6) | C32—C37 | 1.517 (4) |
Ru—Cl2 | 2.3600 (6) | C33—C34 | 1.383 (4) |
C11—N12 | 1.338 (3) | C33—H33 | 0.9500 |
C11—N15 | 1.355 (3) | C34—C35 | 1.376 (4) |
N12—C21 | 1.443 (3) | C34—C38 | 1.509 (4) |
N12—C13 | 1.479 (3) | C35—C36 | 1.401 (4) |
C13—C14 | 1.530 (3) | C35—H35 | 0.9500 |
C13—H13A | 0.9900 | C36—C39 | 1.493 (4) |
C13—H13B | 0.9900 | C37—H37A | 0.9800 |
C14—N15 | 1.480 (3) | C37—H37B | 0.9800 |
C14—H14A | 0.9900 | C37—H37C | 0.9800 |
C14—H14B | 0.9900 | C38—H38A | 0.9800 |
N15—C31 | 1.435 (3) | C38—H38B | 0.9800 |
C21—C22 | 1.393 (3) | C38—H38C | 0.9800 |
C21—C26 | 1.396 (3) | C39—H39A | 0.9800 |
C22—C23 | 1.392 (3) | C39—H39B | 0.9800 |
C22—C27 | 1.502 (3) | C39—H39C | 0.9800 |
C23—C24 | 1.393 (3) | C41—C42 | 1.458 (3) |
C23—H23 | 0.9500 | C41—H41 | 0.9500 |
C24—C25 | 1.393 (4) | C42—C43 | 1.398 (3) |
C24—C28 | 1.511 (3) | C42—C47 | 1.420 (3) |
C25—C26 | 1.398 (3) | C43—C44 | 1.384 (3) |
C25—H25 | 0.9500 | C43—H43 | 0.9500 |
C26—C29 | 1.504 (4) | C44—C45 | 1.377 (4) |
C27—H27A | 0.9800 | C44—H44 | 0.9500 |
C27—H27B | 0.9800 | C45—C46 | 1.395 (4) |
C27—H27C | 0.9800 | C45—H45 | 0.9500 |
C28—H28A | 0.9800 | C46—C47 | 1.393 (3) |
C28—H28B | 0.9800 | C46—H46 | 0.9500 |
C28—H28C | 0.9800 | C47—C48 | 1.445 (3) |
C29—H29A | 0.9800 | C48—O49 | 1.242 (3) |
C29—H29B | 0.9800 | C48—H48 | 0.9500 |
C29—H29C | 0.9800 | ||
C41—Ru—C11 | 97.98 (9) | C26—C29—H29C | 109.5 |
C41—Ru—O49 | 91.12 (8) | H29A—C29—H29C | 109.5 |
C11—Ru—O49 | 94.35 (8) | H29B—C29—H29C | 109.5 |
C41—Ru—Cl1 | 89.81 (7) | C32—C31—C36 | 121.2 (2) |
C11—Ru—Cl1 | 87.90 (7) | C32—C31—N15 | 118.9 (2) |
O49—Ru—Cl1 | 177.42 (5) | C36—C31—N15 | 119.7 (2) |
C41—Ru—Cl2 | 111.76 (7) | C33—C32—C31 | 118.4 (2) |
C11—Ru—Cl2 | 150.16 (7) | C33—C32—C37 | 119.3 (2) |
O49—Ru—Cl2 | 87.66 (5) | C31—C32—C37 | 122.2 (2) |
Cl1—Ru—Cl2 | 89.76 (2) | C34—C33—C32 | 121.9 (2) |
N12—C11—N15 | 108.25 (19) | C34—C33—H33 | 119.0 |
N12—C11—Ru | 133.55 (16) | C32—C33—H33 | 119.0 |
N15—C11—Ru | 118.14 (16) | C35—C34—C33 | 118.4 (2) |
C11—N12—C21 | 126.60 (18) | C35—C34—C38 | 121.4 (3) |
C11—N12—C13 | 113.14 (19) | C33—C34—C38 | 120.2 (3) |
C21—N12—C13 | 120.26 (18) | C34—C35—C36 | 122.8 (2) |
N12—C13—C14 | 102.93 (18) | C34—C35—H35 | 118.6 |
N12—C13—H13A | 111.2 | C36—C35—H35 | 118.6 |
C14—C13—H13A | 111.2 | C35—C36—C31 | 117.1 (2) |
N12—C13—H13B | 111.2 | C35—C36—C39 | 120.5 (2) |
C14—C13—H13B | 111.2 | C31—C36—C39 | 122.4 (2) |
H13A—C13—H13B | 109.1 | C32—C37—H37A | 109.5 |
N15—C14—C13 | 102.29 (19) | C32—C37—H37B | 109.5 |
N15—C14—H14A | 111.3 | H37A—C37—H37B | 109.5 |
C13—C14—H14A | 111.3 | C32—C37—H37C | 109.5 |
N15—C14—H14B | 111.3 | H37A—C37—H37C | 109.5 |
C13—C14—H14B | 111.3 | H37B—C37—H37C | 109.5 |
H14A—C14—H14B | 109.2 | C34—C38—H38A | 109.5 |
C11—N15—C31 | 123.7 (2) | C34—C38—H38B | 109.5 |
C11—N15—C14 | 112.87 (19) | H38A—C38—H38B | 109.5 |
C31—N15—C14 | 120.67 (18) | C34—C38—H38C | 109.5 |
C22—C21—C26 | 122.7 (2) | H38A—C38—H38C | 109.5 |
C22—C21—N12 | 118.5 (2) | H38B—C38—H38C | 109.5 |
C26—C21—N12 | 118.8 (2) | C36—C39—H39A | 109.5 |
C23—C22—C21 | 117.4 (2) | C36—C39—H39B | 109.5 |
C23—C22—C27 | 120.8 (2) | H39A—C39—H39B | 109.5 |
C21—C22—C27 | 121.8 (2) | C36—C39—H39C | 109.5 |
C22—C23—C24 | 122.1 (2) | H39A—C39—H39C | 109.5 |
C22—C23—H23 | 118.9 | H39B—C39—H39C | 109.5 |
C24—C23—H23 | 118.9 | C42—C41—Ru | 127.91 (17) |
C25—C24—C23 | 118.6 (2) | C42—C41—H41 | 116.0 |
C25—C24—C28 | 120.9 (2) | Ru—C41—H41 | 116.0 |
C23—C24—C28 | 120.5 (2) | C43—C42—C47 | 117.5 (2) |
C24—C25—C26 | 121.4 (2) | C43—C42—C41 | 118.7 (2) |
C24—C25—H25 | 119.3 | C47—C42—C41 | 123.7 (2) |
C26—C25—H25 | 119.3 | C44—C43—C42 | 121.0 (2) |
C21—C26—C25 | 117.7 (2) | C44—C43—H43 | 119.5 |
C21—C26—C29 | 121.4 (2) | C42—C43—H43 | 119.5 |
C25—C26—C29 | 120.9 (2) | C45—C44—C43 | 121.5 (2) |
C22—C27—H27A | 109.5 | C45—C44—H44 | 119.3 |
C22—C27—H27B | 109.5 | C43—C44—H44 | 119.3 |
H27A—C27—H27B | 109.5 | C44—C45—C46 | 119.0 (2) |
C22—C27—H27C | 109.5 | C44—C45—H45 | 120.5 |
H27A—C27—H27C | 109.5 | C46—C45—H45 | 120.5 |
H27B—C27—H27C | 109.5 | C47—C46—C45 | 120.4 (2) |
C24—C28—H28A | 109.5 | C47—C46—H46 | 119.8 |
C24—C28—H28B | 109.5 | C45—C46—H46 | 119.8 |
H28A—C28—H28B | 109.5 | C46—C47—C42 | 120.6 (2) |
C24—C28—H28C | 109.5 | C46—C47—C48 | 117.4 (2) |
H28A—C28—H28C | 109.5 | C42—C47—C48 | 122.0 (2) |
H28B—C28—H28C | 109.5 | O49—C48—C47 | 125.4 (2) |
C26—C29—H29A | 109.5 | O49—C48—H48 | 117.3 |
C26—C29—H29B | 109.5 | C47—C48—H48 | 117.3 |
H29A—C29—H29B | 109.5 | C48—O49—Ru | 128.47 (15) |
C41—Ru—C11—N12 | −5.8 (3) | C14—N15—C31—C32 | −81.5 (3) |
O49—Ru—C11—N12 | 85.9 (2) | C11—N15—C31—C36 | −106.7 (3) |
Cl1—Ru—C11—N12 | −95.3 (2) | C14—N15—C31—C36 | 93.5 (3) |
Cl2—Ru—C11—N12 | 178.85 (15) | C36—C31—C32—C33 | 4.1 (4) |
C41—Ru—C11—N15 | 170.79 (18) | N15—C31—C32—C33 | 179.0 (2) |
O49—Ru—C11—N15 | −97.46 (18) | C36—C31—C32—C37 | −173.4 (2) |
Cl1—Ru—C11—N15 | 81.27 (17) | N15—C31—C32—C37 | 1.4 (3) |
Cl2—Ru—C11—N15 | −4.6 (3) | C31—C32—C33—C34 | −1.6 (4) |
N15—C11—N12—C21 | 179.8 (2) | C37—C32—C33—C34 | 176.1 (2) |
Ru—C11—N12—C21 | −3.4 (4) | C32—C33—C34—C35 | −1.2 (4) |
N15—C11—N12—C13 | 0.3 (3) | C32—C33—C34—C38 | 179.8 (3) |
Ru—C11—N12—C13 | 177.2 (2) | C33—C34—C35—C36 | 1.6 (4) |
C11—N12—C13—C14 | 4.1 (3) | C38—C34—C35—C36 | −179.5 (3) |
C21—N12—C13—C14 | −175.4 (2) | C34—C35—C36—C31 | 0.9 (4) |
N12—C13—C14—N15 | −6.4 (3) | C34—C35—C36—C39 | −178.3 (2) |
N12—C11—N15—C31 | −166.3 (2) | C32—C31—C36—C35 | −3.7 (4) |
Ru—C11—N15—C31 | 16.3 (3) | N15—C31—C36—C35 | −178.6 (2) |
N12—C11—N15—C14 | −5.1 (3) | C32—C31—C36—C39 | 175.4 (2) |
Ru—C11—N15—C14 | 177.51 (17) | N15—C31—C36—C39 | 0.6 (4) |
C13—C14—N15—C11 | 7.4 (3) | C11—Ru—C41—C42 | 106.4 (2) |
C13—C14—N15—C31 | 169.2 (2) | O49—Ru—C41—C42 | 11.9 (2) |
C11—N12—C21—C22 | −91.5 (3) | Cl1—Ru—C41—C42 | −165.7 (2) |
C13—N12—C21—C22 | 87.9 (3) | Cl2—Ru—C41—C42 | −76.1 (2) |
C11—N12—C21—C26 | 91.2 (3) | Ru—C41—C42—C43 | 171.49 (18) |
C13—N12—C21—C26 | −89.4 (3) | Ru—C41—C42—C47 | −8.6 (3) |
C26—C21—C22—C23 | −1.8 (3) | C47—C42—C43—C44 | −0.2 (3) |
N12—C21—C22—C23 | −178.94 (19) | C41—C42—C43—C44 | 179.7 (2) |
C26—C21—C22—C27 | 178.3 (2) | C42—C43—C44—C45 | −0.5 (4) |
N12—C21—C22—C27 | 1.1 (3) | C43—C44—C45—C46 | 0.7 (4) |
C21—C22—C23—C24 | 0.9 (3) | C44—C45—C46—C47 | −0.3 (4) |
C27—C22—C23—C24 | −179.2 (2) | C45—C46—C47—C42 | −0.3 (4) |
C22—C23—C24—C25 | 0.4 (4) | C45—C46—C47—C48 | −179.0 (2) |
C22—C23—C24—C28 | −179.0 (2) | C43—C42—C47—C46 | 0.5 (3) |
C23—C24—C25—C26 | −0.9 (4) | C41—C42—C47—C46 | −179.3 (2) |
C28—C24—C25—C26 | 178.6 (2) | C43—C42—C47—C48 | 179.2 (2) |
C22—C21—C26—C25 | 1.4 (3) | C41—C42—C47—C48 | −0.7 (3) |
N12—C21—C26—C25 | 178.5 (2) | C46—C47—C48—O49 | 179.8 (2) |
C22—C21—C26—C29 | −179.5 (2) | C42—C47—C48—O49 | 1.1 (4) |
N12—C21—C26—C29 | −2.4 (3) | C47—C48—O49—Ru | 7.0 (3) |
C24—C25—C26—C21 | 0.0 (3) | C41—Ru—O49—C48 | −11.70 (19) |
C24—C25—C26—C29 | −179.1 (2) | C11—Ru—O49—C48 | −109.79 (19) |
C11—N15—C31—C32 | 78.3 (3) | Cl2—Ru—O49—C48 | 100.04 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
C29—H29C···Cl1 | 0.98 | 2.67 | 3.634 (3) | 166 |
C39—H39C···Cl1 | 0.98 | 2.76 | 3.371 (3) | 121 |
C37—H37A···O49 | 0.98 | 2.39 | 3.268 (3) | 150 |
C13—H13B···Cl1i | 0.99 | 2.94 | 3.395 (2) | 109 |
C14—H14A···Cl1i | 0.99 | 2.90 | 3.324 (3) | 107 |
C27—H27A···Cl2i | 0.98 | 2.85 | 3.724 (3) | 149 |
C37—H37C···Cl2i | 0.98 | 2.88 | 3.736 (3) | 146 |
C25—H25···Cl1ii | 0.95 | 2.98 | 3.831 (3) | 150 |
C29—H29A···Cl1ii | 0.98 | 2.71 | 3.673 (3) | 169 |
C46—H46···Cl2iii | 0.95 | 3.04 | 3.553 (2) | 115 |
C48—H48···O49iii | 0.95 | 2.50 | 3.014 (3) | 114 |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −y+1, x, −z; (iii) −x, −y+1, z. |
Experimental details
Crystal data | |
Chemical formula | [RuCl2(C8H6O)(C21H26N2)]·C4H10O |
Mr | 670.66 |
Crystal system, space group | Tetragonal, P4c2 |
Temperature (K) | 100 |
a, c (Å) | 19.8603 (4), 15.6582 (7) |
V (Å3) | 6176.1 (3) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.71 |
Crystal size (mm) | 0.43 × 0.25 × 0.22 |
Data collection | |
Diffractometer | Bruker SMART APEX CCD |
Absorption correction | Multi-scan (SADABS; Bruker, 2003) |
Tmin, Tmax | 0.78, 0.86 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 90504, 8992, 7306 |
Rint | 0.058 |
(sin θ/λ)max (Å−1) | 0.704 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.067, 1.01 |
No. of reflections | 8992 |
No. of parameters | 322 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.42, −0.31 |
Absolute structure | Flack (1983), 4175 Friedel pairs |
Absolute structure parameter | −0.02 (2) |
Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SAINT, SADABS and XPREP (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
C29—H29C···Cl1 | 0.98 | 2.67 | 3.634 (3) | 166.3 |
C39—H39C···Cl1 | 0.98 | 2.76 | 3.371 (3) | 121.2 |
C37—H37A···O49 | 0.98 | 2.39 | 3.268 (3) | 149.5 |
C13—H13B···Cl1i | 0.99 | 2.94 | 3.395 (2) | 109.1 |
C14—H14A···Cl1i | 0.99 | 2.90 | 3.324 (3) | 106.5 |
C27—H27A···Cl2i | 0.98 | 2.85 | 3.724 (3) | 149.0 |
C37—H37C···Cl2i | 0.98 | 2.88 | 3.736 (3) | 146.3 |
C25—H25···Cl1ii | 0.95 | 2.98 | 3.831 (3) | 149.9 |
C29—H29A···Cl1ii | 0.98 | 2.71 | 3.673 (3) | 168.7 |
C46—H46···Cl2iii | 0.95 | 3.04 | 3.553 (2) | 115.4 |
C48—H48···O49iii | 0.95 | 2.50 | 3.014 (3) | 114.1 |
Symmetry codes: (i) x, −y+1, z+1/2; (ii) −y+1, x, −z; (iii) −x, −y+1, z. |
Acknowledgements
Financial support by the EC Project `EuMet' (grant No. CPFP 211468-2) is gratefully acknowledged.
References
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The ruthenium complex RuCl2(C8H6O)(C21H26N2), which is the main constituent of the title compound, (I), was prepared by a carbene exchange reaction of (H2IMes)(pyridine)2(Cl)2RuCHPh (1eq.; H2IMes = 1,3-bismesityl-4,5-dihydroimidazol-2-ylidene) with 2-vinylbenzaldehyde (2 eq.) in CH2Cl2 at room temperature (Slugovc et al., 2004). In sharp contrast to most of the ruthenium carbene complexes bearing two halides and neutral donor co-ligands (phosphines or N-heterocyclic carbenes), which exhibit a trans stereochemistry of the two halide ligands, the ruthenium complex of the title compound bears them in a cis-disposition of a square pyramidal coordination about Ru, the apex of which is formed by the benzylidene carbon C41 with a characteristically short Ru—C bond of 1.827 (2) Å whereas the bond to the N-heterocyclic carbene carbon C11 is longer by 0.077 Å (Fig. 1 and Table 1). It has been shown, that cis-isomer is thermodynamically favoured over its trans-dichlorido counterpart (Slugovc et al., 2004). Ruthenium carbene complexes bearing a cis-dichlorido arrangement are particularly interesting, because they exhibit distinctly lower initiation rates in ring opening metathesis polymerization (ROMP) of strained cyclic olefins when compared to their trans-dichlorido counterparts (Gstrein et al., 2007). This feature is used to design latent ROMP initiators and catalysts for e.g. ring closing metathesis at elevated temperatures (Szadkowska & Grela, 2008; Burtscher et al., 2006; Vougioukalakis & Grubbs, 2010).
A view of the Ru complex in the title compound is presented in Fig. 1. Bond lengths and angles about Ru (Table 1) are in good agreement with the bis-dichloromethane solvate of the same complex, RuCl2(C8H6O)(C21H26N2).2CH2Cl2, which crystallizes in a moclinic lattice, space group P21/c, a = 12.1933 (6), b = 15.4520 (7), c = 19.3799 (9) Å, β = 108.181 (1)°, V = 3469.1 (3) Å3, Z = 4 (Slugovc et al., 2004). Both complexes, in (I) and in the dichloromethane solvate, show similar conformations and are stabilized by significant intramolecular π-π stacking interactions between the 2-formylbenzylidene and the adjacent mesityl moiety with the shortest intramolecular π-π contacts of C41···C21 = 3.00 Å, C42···C22 = 3.40 Å, and C43···C24 = 3.45 Å in (I) and 2.99, 3.42, and 3.43 Å in the dichloromethane solvate. Moreover, both complexes show intramolecular C—H···O,Cl interactions, e.g. in (I) between C37 and Cl1 and and C29 and Cl1 (Fig. 1 and Table 2). In contrast to the dichloromethane solvate, where the Ru complexes do not show any intermolecular π-π-stacking but are held together mainly by C—H···π and C—H···Cl intercations, intermolecular π-π-stacking is an important factor in the crystal structure of (I). Fig. 2 demonstrates that the structure of (I) contains columnar stacks of molecules extending along the c-axis and showing intermolecular π-π-stacking between the formylbenzylidene and one of the two mesityl groups [corresponding π-π-contacts are C44···C33(x,1 - y,-1/2 + z) = 3.59 Å and C43···C32(x,1 - y,-1/2 + z) = 3.81 Å]. Further π-π-stacking interactions arise from the mutual indentation of these stacks [corresponding π-π-contacts are C22···C24(y,x,1/2 - z) = 3.82 Å, C23···C23(y,x,1/2 - z) = 3.64 Å and C24···C22(y,x,1/2 - z) = 3.82 Å]. Finally, the Ru-complexes are also held together by a larger number of weak intermolecular C—H···Cl,O interactions (Table 2). The result of all these interactions between the Ru complexes in (I) is a framework-like structure of tetragonal symmetry containing continuous channels which extend along the c-axis and contain the diethyl ether solvent molecules. As shown in Fig. 3, there are two different kinds of continuous channels in the this framework, both coinciding with the two crystallographically different sets of 4 axes of the lattice. The larger channel in this framework is centered at x,y = 0,0 and has a minimal net-diameter in the (001)-projection of 5.6 Å and a solvent-accessible volume per unit cell of 695 Å3 (program PLATON; Spek, 2009). The smaller channel is centered at x,y = 1/2,1/2, has in the projection a minimal net-diameter of 4.2 Å and a solvent-accessible volume per unit cell of 464 Å3. As described in the experimental section, the diethyl ether solvent molecules inside these channels are disordered with about 5 molecules per unit cell in the large and about 3 molecules per unit cell in the small channel.