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metal-organic compounds
| CRYSTALLOGRAPHIC COMMUNICATIONS |
accessBis(η5-pentamethylcyclopentadienyl)cobalt(II)
aDepartment of Chemistry, University of Rochester, Rochester, NY 14627, USA
*Correspondence e-mail: brennessel@chem.rochester.edu
The of the title compound, decamethylcobaltocene, [Co(C10H15)2], has been determined. High-quality single crystals were grown from a cold saturated hexamethyldisiloxane solution. The structure is related to the manganese and iron analogs. The molecule has D5d symmetry, with the Co atom in a crystallographic 2/m position. The cobalt–centroid(C5) distance is 1.71Å and the centroid(C5)–Co–centroid(C5) angle is 180°, by symmetry.
Related literature
For the synthesis of the title compound and its electrochemical and magnetic properties, see: Robbins et al. (1982![[Robbins, J. L., Edelstein, N., Spencer, B. & Smart, J. C. (1982). J. Am. Chem. Soc. 104, 1882-1893.]](../../../../../../logos/arrows/e_arr.gif "Robbins, J. L., Edelstein, N., Spencer, B. & Smart, J. C. (1982). J. Am. Chem. Soc. 104, 1882-1893.")
). For its and use as a reducing agent, see: Connelly & Geiger (1996). For the isotypic manganese and iron structures, see: Struchkov et al. (1978); Freyburg et al. (1979); Augart et al. (1991); Arrais et al. (2003).
![[Scheme 1]](sj2590scheme1.gif)
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL.
Supporting information
contains datablocks I, global. DOI: 10.1107/S1600536809007971/sj2590sup1.cif
Structure factors: contains datablock I. DOI: 10.1107/S1600536809007971/sj2590Isup2.hkl
All operations were performed under an inert atmosphere (dinitrogen). Hexamethyldisiloxane was stirred over CaH2 and vacuum transferred from sodium benzophenone ketyl. (I) was purchased from Sigma-Aldrich and used as is. Hexamethyldisiloxane (1 ml) was added to (I) (10 mg, 30 µmol), most of which dissolved over the course of a few hours at room temperature. After filtration through Celite, the filtrate was stored at -38 °C, resulting in dark yellow-brown crystals of (I) after a few hours.
Hydrogen atoms were found from the difference Fourier map and refined independently from their respective carbon atoms with individual isotropic displacement parameters.
Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).
![[Figure 1]](./sj2590fig1thm.gif) | Fig. 1. A displacement ellipsoid (50% probability) drawing of (I). The cobalt atom is in a crystallographic 2/m position. |
| [Co(C10H15)2] | F(000) = 708 |
| Mr = 329.37 | Dx = 1.259 Mg m−3 |
| Orthorhombic, Cmca | Mo Kα radiation, λ = 0.71073 Å |
| Hall symbol: -C 2bc 2 | Cell parameters from 4000 reflections |
| a = 15.0848 (16) Å | θ = 3.0–37.5° |
| b = 11.5031 (12) Å | µ = 0.98 mm−1 |
| c = 10.0105 (10) Å | T = 100 K |
| V = 1737.0 (3) Å3 | Block, dark yellow-brown |
| Z = 4 | 0.28 × 0.28 × 0.14 mm |
| Bruker APEXII CCD diffractometer | 2386 independent reflections |
| Radiation source: fine-focus sealed tube | 1903 reflections with I > 2σ(I) |
| Graphite monochromator | Rint = 0.046 |
| ϕ and ω scans | θmax = 38.0°, θmin = 2.7° |
| Absorption correction: multi-scan (SADABS; Sheldrick, 2008a) | h = −25→25 |
| Tmin = 0.771, Tmax = 0.875 | k = −19→19 |
| 19672 measured reflections | l = −16→17 |
| Refinement on F2 | Primary atom site location: structure-invariant direct methods |
| Least-squares matrix: full | Secondary atom site location: difference Fourier map |
| R[F2 > 2σ(F2)] = 0.031 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.089 | All H-atom parameters refined |
| S = 1.07 | w = 1/[σ2(Fo2) + (0.0525P)2 + 0.2743P] where P = (Fo2 + 2Fc2)/3 |
| 2386 reflections | (Δ/σ)max < 0.001 |
| 84 parameters | Δρmax = 0.70 e Å−3 |
| 0 restraints | Δρmin = −0.74 e Å−3 |
| [Co(C10H15)2] | V = 1737.0 (3) Å3 |
| Mr = 329.37 | Z = 4 |
| Orthorhombic, Cmca | Mo Kα radiation |
| a = 15.0848 (16) Å | µ = 0.98 mm−1 |
| b = 11.5031 (12) Å | T = 100 K |
| c = 10.0105 (10) Å | 0.28 × 0.28 × 0.14 mm |
| Bruker APEXII CCD diffractometer | 2386 independent reflections |
| Absorption correction: multi-scan (SADABS; Sheldrick, 2008a) | 1903 reflections with I > 2σ(I) |
| Tmin = 0.771, Tmax = 0.875 | Rint = 0.046 |
| 19672 measured reflections |
| R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
| wR(F2) = 0.089 | All H-atom parameters refined |
| S = 1.07 | Δρmax = 0.70 e Å−3 |
| 2386 reflections | Δρmin = −0.74 e Å−3 |
| 84 parameters |
Experimental. The crystal was examined under N2 and affixed to the end of a glass capillary with viscous oil, which protected the crystal during transfer to the cold stream. |
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 | ||
| Co1 | 0.0000 | 0.0000 | 0.0000 | 0.01533 (7) | |
| C1 | 0.0000 | −0.17732 (10) | 0.04617 (12) | 0.0228 (2) | |
| C2 | −0.07677 (6) | −0.12416 (7) | 0.10364 (8) | 0.02149 (15) | |
| C3 | −0.04749 (5) | −0.03551 (7) | 0.19244 (8) | 0.01843 (13) | |
| C4 | 0.0000 | −0.27361 (12) | −0.05429 (14) | 0.0348 (3) | |
| H4A | 0.0000 | −0.352 (3) | −0.013 (2) | 0.045 (8)* | |
| H4B | −0.0486 (10) | −0.2711 (18) | −0.1133 (16) | 0.063 (5)* | |
| C5 | −0.17089 (8) | −0.15651 (11) | 0.07606 (12) | 0.0340 (2) | |
| H5A | −0.1798 (16) | −0.184 (2) | −0.0134 (18) | 0.053 (6)* | |
| H5B | −0.2119 (12) | −0.0926 (16) | 0.0778 (19) | 0.059 (5)* | |
| H5C | −0.1896 (11) | −0.2189 (15) | 0.1358 (16) | 0.047 (4)* | |
| C6 | −0.10544 (7) | 0.04079 (10) | 0.27607 (9) | 0.02731 (18) | |
| H6A | −0.1134 (15) | 0.0057 (13) | 0.360 (3) | 0.045 (6)* | |
| H6B | −0.1638 (11) | 0.0562 (13) | 0.2287 (15) | 0.039 (4)* | |
| H6C | −0.0774 (11) | 0.1158 (14) | 0.2912 (14) | 0.037 (4)* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Co1 | 0.01811 (10) | 0.01380 (9) | 0.01409 (9) | 0.000 | 0.000 | −0.00032 (6) |
| C1 | 0.0353 (6) | 0.0161 (4) | 0.0170 (4) | 0.000 | 0.000 | −0.0004 (4) |
| C2 | 0.0245 (3) | 0.0202 (3) | 0.0198 (3) | −0.0054 (3) | −0.0013 (3) | 0.0016 (3) |
| C3 | 0.0205 (3) | 0.0180 (3) | 0.0168 (3) | 0.0002 (3) | 0.0014 (2) | 0.0006 (2) |
| C4 | 0.0653 (11) | 0.0183 (5) | 0.0206 (5) | 0.000 | 0.000 | −0.0029 (4) |
| C5 | 0.0290 (4) | 0.0371 (5) | 0.0359 (5) | −0.0147 (4) | −0.0069 (4) | 0.0063 (4) |
| C6 | 0.0293 (4) | 0.0292 (4) | 0.0234 (4) | 0.0056 (4) | 0.0068 (3) | −0.0005 (3) |
| Co1—C1i | 2.0914 (12) | C2—C3 | 1.4231 (12) |
| Co1—C1 | 2.0914 (12) | C2—C5 | 1.4935 (14) |
| Co1—C3ii | 2.0955 (8) | C3—C3ii | 1.4328 (17) |
| Co1—C3 | 2.0956 (8) | C3—C6 | 1.4950 (13) |
| Co1—C3i | 2.0956 (8) | C4—H4A | 0.99 (3) |
| Co1—C3iii | 2.0956 (8) | C4—H4B | 0.942 (16) |
| Co1—C2iii | 2.1113 (8) | C5—H5A | 0.960 (18) |
| Co1—C2 | 2.1113 (8) | C5—H5B | 0.962 (18) |
| Co1—C2ii | 2.1113 (8) | C5—H5C | 0.976 (17) |
| Co1—C2i | 2.1113 (8) | C6—H6A | 0.94 (2) |
| C1—C2 | 1.4304 (12) | C6—H6B | 1.016 (16) |
| C1—C2ii | 1.4304 (12) | C6—H6C | 0.973 (16) |
| C1—C4 | 1.4961 (18) | ||
| C1i—Co1—C1 | 180.0 | C3—Co1—C2i | 140.46 (3) |
| C1i—Co1—C3ii | 113.16 (4) | C3i—Co1—C2i | 39.54 (3) |
| C1—Co1—C3ii | 66.84 (4) | C3iii—Co1—C2i | 66.67 (3) |
| C1i—Co1—C3 | 113.16 (4) | C2iii—Co1—C2i | 66.53 (5) |
| C1—Co1—C3 | 66.84 (4) | C2—Co1—C2i | 180.0 |
| C3ii—Co1—C3 | 39.98 (5) | C2ii—Co1—C2i | 113.47 (5) |
| C1i—Co1—C3i | 66.84 (4) | C2—C1—C2ii | 108.12 (10) |
| C1—Co1—C3i | 113.16 (4) | C2—C1—C4 | 125.94 (5) |
| C3ii—Co1—C3i | 140.02 (5) | C2ii—C1—C4 | 125.93 (5) |
| C3—Co1—C3i | 180.0 | C2—C1—Co1 | 70.85 (6) |
| C1i—Co1—C3iii | 66.84 (4) | C2ii—C1—Co1 | 70.85 (6) |
| C1—Co1—C3iii | 113.16 (4) | C4—C1—Co1 | 124.99 (9) |
| C3ii—Co1—C3iii | 180.0 | C3—C2—C1 | 107.84 (8) |
| C3—Co1—C3iii | 140.02 (5) | C3—C2—C5 | 126.09 (9) |
| C3i—Co1—C3iii | 39.98 (5) | C1—C2—C5 | 126.07 (9) |
| C1i—Co1—C2iii | 39.79 (3) | C3—C2—Co1 | 69.63 (5) |
| C1—Co1—C2iii | 140.21 (3) | C1—C2—Co1 | 69.36 (6) |
| C3ii—Co1—C2iii | 140.46 (3) | C5—C2—Co1 | 126.81 (7) |
| C3—Co1—C2iii | 113.34 (3) | C2—C3—C3ii | 108.08 (5) |
| C3i—Co1—C2iii | 66.66 (3) | C2—C3—C6 | 126.09 (8) |
| C3iii—Co1—C2iii | 39.54 (3) | C3ii—C3—C6 | 125.78 (5) |
| C1i—Co1—C2 | 140.21 (3) | C2—C3—Co1 | 70.82 (5) |
| C1—Co1—C2 | 39.79 (3) | C3ii—C3—Co1 | 70.01 (2) |
| C3ii—Co1—C2 | 66.67 (3) | C6—C3—Co1 | 126.88 (6) |
| C3—Co1—C2 | 39.54 (3) | C1—C4—H4A | 112.8 (13) |
| C3i—Co1—C2 | 140.46 (3) | C1—C4—H4B | 113.5 (11) |
| C3iii—Co1—C2 | 113.33 (3) | H4A—C4—H4B | 107.0 (15) |
| C2iii—Co1—C2 | 113.47 (5) | C2—C5—H5A | 112.8 (15) |
| C1i—Co1—C2ii | 140.21 (3) | C2—C5—H5B | 114.7 (11) |
| C1—Co1—C2ii | 39.79 (3) | H5A—C5—H5B | 100.5 (18) |
| C3ii—Co1—C2ii | 39.54 (3) | C2—C5—H5C | 110.1 (9) |
| C3—Co1—C2ii | 66.67 (3) | H5A—C5—H5C | 106.7 (16) |
| C3i—Co1—C2ii | 113.33 (3) | H5B—C5—H5C | 111.4 (14) |
| C3iii—Co1—C2ii | 140.46 (3) | C3—C6—H6A | 109.0 (11) |
| C2iii—Co1—C2ii | 180.0 | C3—C6—H6B | 110.4 (9) |
| C2—Co1—C2ii | 66.53 (5) | H6A—C6—H6B | 112.4 (16) |
| C1i—Co1—C2i | 39.79 (3) | C3—C6—H6C | 110.7 (9) |
| C1—Co1—C2i | 140.21 (3) | H6A—C6—H6C | 107.2 (15) |
| C3ii—Co1—C2i | 113.33 (3) | H6B—C6—H6C | 107.2 (13) |
| C1i—Co1—C1—C2 | 22.38 (12) | C2iii—Co1—C2—C1 | 141.96 (6) |
| C3ii—Co1—C1—C2 | 80.81 (6) | C2ii—Co1—C2—C1 | −38.04 (6) |
| C3—Co1—C1—C2 | 37.16 (5) | C2i—Co1—C2—C1 | −59.99 (6) |
| C3i—Co1—C1—C2 | −142.84 (5) | C1i—Co1—C2—C5 | 59.74 (11) |
| C3iii—Co1—C1—C2 | −99.18 (6) | C1—Co1—C2—C5 | −120.26 (11) |
| C2iii—Co1—C1—C2 | −62.03 (10) | C3ii—Co1—C2—C5 | 158.44 (10) |
| C2ii—Co1—C1—C2 | 117.97 (10) | C3—Co1—C2—C5 | 120.46 (11) |
| C2i—Co1—C1—C2 | 180.0 | C3i—Co1—C2—C5 | −59.54 (11) |
| C1i—Co1—C1—C2ii | −95.59 (13) | C3iii—Co1—C2—C5 | −21.56 (10) |
| C3ii—Co1—C1—C2ii | −37.16 (5) | C2iii—Co1—C2—C5 | 21.70 (8) |
| C3—Co1—C1—C2ii | −80.82 (6) | C2ii—Co1—C2—C5 | −158.30 (8) |
| C3i—Co1—C1—C2ii | 99.18 (6) | C2i—Co1—C2—C5 | 179.75 (9) |
| C3iii—Co1—C1—C2ii | 142.84 (5) | C1—C2—C3—C3ii | −1.34 (8) |
| C2iii—Co1—C1—C2ii | 180.0 | C5—C2—C3—C3ii | 178.27 (8) |
| C2—Co1—C1—C2ii | −117.97 (10) | Co1—C2—C3—C3ii | −60.38 (2) |
| C2i—Co1—C1—C2ii | 62.03 (10) | C1—C2—C3—C6 | −178.77 (9) |
| C1i—Co1—C1—C4 | 143.40 (12) | C5—C2—C3—C6 | 0.85 (14) |
| C3ii—Co1—C1—C4 | −158.17 (3) | Co1—C2—C3—C6 | 122.20 (9) |
| C3—Co1—C1—C4 | 158.17 (3) | C1—C2—C3—Co1 | 59.04 (7) |
| C3i—Co1—C1—C4 | −21.83 (3) | C5—C2—C3—Co1 | −121.35 (9) |
| C3iii—Co1—C1—C4 | 21.83 (3) | C1i—Co1—C3—C2 | 142.61 (5) |
| C2iii—Co1—C1—C4 | 58.98 (5) | C1—Co1—C3—C2 | −37.39 (5) |
| C2—Co1—C1—C4 | 121.01 (5) | C3ii—Co1—C3—C2 | −118.44 (5) |
| C2ii—Co1—C1—C4 | −121.01 (5) | C3i—Co1—C3—C2 | −112.12 (6) |
| C2i—Co1—C1—C4 | −58.99 (5) | C3iii—Co1—C3—C2 | 61.56 (5) |
| C2ii—C1—C2—C3 | 2.17 (13) | C2iii—Co1—C3—C2 | 99.14 (7) |
| C4—C1—C2—C3 | −179.08 (11) | C2ii—Co1—C3—C2 | −80.87 (7) |
| Co1—C1—C2—C3 | −59.21 (6) | C2i—Co1—C3—C2 | 180.0 |
| C2ii—C1—C2—C5 | −177.44 (7) | C1i—Co1—C3—C3ii | −98.952 (19) |
| C4—C1—C2—C5 | 1.30 (17) | C1—Co1—C3—C3ii | 81.049 (19) |
| Co1—C1—C2—C5 | 121.18 (9) | C3i—Co1—C3—C3ii | 6.32 (2) |
| C2ii—C1—C2—Co1 | 61.38 (8) | C3iii—Co1—C3—C3ii | 180.0 |
| C4—C1—C2—Co1 | −119.87 (12) | C2iii—Co1—C3—C3ii | −142.43 (3) |
| C1i—Co1—C2—C3 | −60.72 (8) | C2—Co1—C3—C3ii | 118.44 (5) |
| C1—Co1—C2—C3 | 119.28 (8) | C2ii—Co1—C3—C3ii | 37.57 (3) |
| C3ii—Co1—C2—C3 | 37.98 (5) | C2i—Co1—C3—C3ii | −61.56 (5) |
| C3i—Co1—C2—C3 | 180.0 | C1i—Co1—C3—C6 | 21.37 (9) |
| C3iii—Co1—C2—C3 | −142.02 (5) | C1—Co1—C3—C6 | −158.63 (9) |
| C2iii—Co1—C2—C3 | −98.77 (5) | C3ii—Co1—C3—C6 | 120.32 (8) |
| C2ii—Co1—C2—C3 | 81.24 (5) | C3i—Co1—C3—C6 | 126.64 (8) |
| C2i—Co1—C2—C3 | 59.29 (5) | C3iii—Co1—C3—C6 | −59.68 (8) |
| C1i—Co1—C2—C1 | 180.0 | C2iii—Co1—C3—C6 | −22.11 (9) |
| C3ii—Co1—C2—C1 | −81.30 (6) | C2—Co1—C3—C6 | −121.24 (10) |
| C3—Co1—C2—C1 | −119.28 (8) | C2ii—Co1—C3—C6 | 157.89 (9) |
| C3i—Co1—C2—C1 | 60.72 (8) | C2i—Co1—C3—C6 | 58.76 (10) |
| C3iii—Co1—C2—C1 | 98.70 (6) |
| Symmetry codes: (i) −x, −y, −z; (ii) −x, y, z; (iii) x, −y, −z. |
Experimental details
| Crystal data | |
| Chemical formula | [Co(C10H15)2] |
| Mr | 329.37 |
| Crystal system, space group | Orthorhombic, Cmca |
| Temperature (K) | 100 |
| a, b, c (Å) | 15.0848 (16), 11.5031 (12), 10.0105 (10) |
| V (Å3) | 1737.0 (3) |
| Z | 4 |
| Radiation type | Mo Kα |
| µ (mm−1) | 0.98 |
| Crystal size (mm) | 0.28 × 0.28 × 0.14 |
| Data collection | |
| Diffractometer | Bruker APEXII CCD diffractometer |
| Absorption correction | Multi-scan (SADABS; Sheldrick, 2008a) |
| Tmin, Tmax | 0.771, 0.875 |
| No. of measured, independent and observed [I > 2σ(I)] reflections | 19672, 2386, 1903 |
| Rint | 0.046 |
| (sin θ/λ)max (Å−1) | 0.865 |
| Refinement | |
| R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.089, 1.07 |
| No. of reflections | 2386 |
| No. of parameters | 84 |
| H-atom treatment | All H-atom parameters refined |
| Δρmax, Δρmin (e Å−3) | 0.70, −0.74 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008b), SHELXL97 (Sheldrick, 2008b), SHELXTL (Sheldrick, 2008b).
| Co1—C1 | 2.0914 (12) | C1—C4 | 1.4961 (18) |
| Co1—C3 | 2.0956 (8) | C2—C3 | 1.4231 (12) |
| Co1—C2 | 2.1113 (8) | C2—C5 | 1.4935 (14) |
| C1—C2 | 1.4304 (12) | C3—C6 | 1.4950 (13) |
References
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The structure of (I) has been conspicuously absent from the literature, despite its being a widely used reducing agent (Connelly & Geiger, 1996). Robbins and co-workers referred to a structural determination in 1982 (Robbins et al., 1982), specifically its D5d symmetry and its similarity to the manganese analog. However, no structural data were presented. Attempts to grow single crystals from toluene and hexane, the latter from which Robbins reported having grown crystals, resulted in very poor quality specimens that were unsuitable for X-ray diffraction experiments. A cold (-38 ° C) saturated hexamethyldisiloxane solution of (I) afforded excellent crystals that resulted in a high quality structural determination.
The structure is isomorphous to that of decamethylferrocene (refcodes DMFERR, Struchkov et al., 1978, DMFERR01, Freyburg et al., 1979, DMFERR02, Arrais et al., 2003) and the low temperature polymorph of decamethylmanganocene (refcodes DMCPMN01 and DMCPMN02, Augart et al., 1991), for which the metal atoms are in crystallographic 2/m positions.