supplementary materials


HTML versionpdf versioncif file3d viewstructure factorssupplementary materialsCIF check reportsimilar papers Open access

tk2232 scheme

Acta Cryst. (2008). E64, m232    [ doi:10.1107/S1600536807066871 ]

Di-[mu]-iodido-bis[(diethyl ether-[kappa]O)([eta]5-1,3-di-tert-butylcyclopentadienyl)ytterbium(II)]

M. Schultz

Abstract top

The half-sandwich title compound, [Yb2(C13H21)2I2(C4H10O)2], crystallizes as a centrosymmetric dimer. The Yb atom is coordinated in a three-legged piano-stool geometry by a cyclopentadienyl ring, two I anions and the O atom of a diethyl ether molecule. The central Yb2I2 core is an approximate square.

Comment top

The title compound (I) was formed in an attempt to prepare the metallocene of the substituted cyclopentadienyl ligand by stirring one equivalent of the magnesocene (η5-1,3-(Me3C)2C5H3)2Mg with YbI2 in diethyl ether. The reaction can also be performed using half an equivalent of magnesocene. The inital yellow-green slurry forms a deep green solution after stirring for two hours at room temperature. The green color has previously been associated with formation of an ytterbocene. However, upon filtration a thermochroic solution results that is bright-green below -30°C but becomes orange-brown upon warming to room temperature. The bright-orange crystals that form at low temperature do not redissolve in diethyl ether and are insoluble in hydrocarbon solvents. Use of THF as solvent for the reaction leads to transfer of two cyclopentadienide rings to the metal and formation of the known THF adduct [1,3-(Me3C)2C5H3]2Yb(THF) (Schumann et al., 1993).

The structure of (I) is centrosymmetric about a square Yb2I2 core, Fig. 1 & Table 1. There is gross thermal motion in one ethyl group of the diethyl ether ligand, affecting the thermal parameters of C(14) in particular, but this does not adversely impact the quality of the core of the structure. The distances and angles fall within normal ranges for Yb(II) in 6-coordination. (Schultz et al., 2000)

The structure is similar to those of the published dimers {(Me5C5)Yb(THF)2-µ-I}2, {(Me5C5)Yb(dme)-µ-I}2, (Constantine et al., 1996) and {[Me4[SiMe2NH(CMe3)]C5]Yb(THF)2-µ-I}2 (Trifonov et al., 2003), in which the Yb(II) is 7-coordinate.

Related literature top

For related structures, see Constantine et al. (1996); Trifonov et al. (2003). For related chemistry, see: Schultz et al. (2000); Schumann et al. (1993).

Experimental top

The magnesocene [1,3-(Me3C)2C5H3]2Mg (0.5 g, 1.3 mmol) was weighed into a round-bottomed flask equipped with a magnetic stirrer bar. YbI2 (0.56 g, 1.3 mmol) was added under a flow of N2. Et2O was added and the slurry was stirred at room temperature. After 1 h, the solution was green in color. After 3 h, the solution was filtered off the grey solid which appeared to contain unreacted magnesocene by 1H NMR spectroscopy. The volume of the green solution was reduced under reduced pressure; the solid that was deposited on the sides of the flask during this procedure was orange. Cooling to -40°C resulted in the formation of clear orange crystals which were insoluble in OEt2, hot toluene or C6D6. The crystals turn brown at 130°C, and black at 230°C, but do not melt to 330°C. Analysis. Found: C 38.2, H 5.96%. C17H31IOYb requires C 37.0, H 5.67%. The insolubility of the dimer prevented recrystallization or the obtention of an NMR spectrum. Sublimation of the dimer did not lead to the formation of the ytterbocene. The ether adduct of magnesium iodide can be obtained as a first crop of colorless crystals from the mother liquor before crystallization of the orange product, and unreacted [1,3-(Me3C)2C5H3]2Mg can be crystallized from the mother liquor after all of the product has crystallized from the solution.

Refinement top

All H atoms were positioned geometrically and allowed to ride on their parent atoms with C—H distances in the range 0.93–0.97 Å, and with Uiso(H) = 1.5 Ueq(C) for methyl-H atoms and Uiso(H) = 1.2 Ueq(C) for other atoms. The maximum and minimum residual electron density peaks of 0.92 and -1.11 e Å-3 were located 0.94 and 0.94 Å, respectively from the H15A and Yb atoms.

Computing details top

Data collection: SMART (Siemens, 1995); cell refinement: XPREP (Sheldrick, 1995); data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL (Sheldrick, 1998); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top
[Figure 1] Fig. 1. A view of the dimer (I) showing the atom labelling scheme. Hydrogen atoms have been omitted for clarity and displacement ellipsoids are drawn at the 50% probability level. Symmetry operation i: -x + 2, -y + 1, -z + 1.
Di-µ-iodido-bis[(diethyl ether-κO)(η5-1,3-di-tert-butylcyclopentadienyl)ytterbium(II)] top
Crystal data top
[Yb2(C13H21)2I2(C4H10O)2]F000 = 1056
Mr = 1102.72Dx = 1.795 Mg m−3
Monoclinic, P21/nMelting point: 330 K
Hall symbol: -P 2ynMo Kα radiation
λ = 0.71073 Å
a = 13.7190 (3) ÅCell parameters from 6017 reflections
b = 11.1690 (1) Åθ = 2.0–23.3º
c = 14.4440 (3) ŵ = 6.10 mm−1
β = 112.800 (1)ºT = 160 K
V = 2040.28 (6) Å3Plate-like, orange
Z = 20.40 × 0.30 × 0.15 mm
Data collection top
Bruker SMART 1K CCD
diffractometer		2928 independent reflections
Radiation source: fine-focus sealed tube2679 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.033
T = 161(2) Kθmax = 23.3º
ω scansθmin = 1.7º
Absorption correction: multi-scan
(XPREP; Sheldrick, 1995)		h = −15→15
Tmin = 0.192, Tmax = 0.401k = −12→7
8321 measured reflectionsl = −15→16
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.026H-atom parameters constrained
wR(F2) = 0.059  w = 1/[σ2(Fo2) + (0.0144P)2 + 9.3362P]
where P = (Fo2 + 2Fc2)/3
S = 1.09(Δ/σ)max = 0.001
2928 reflectionsΔρmax = 0.92 e Å−3
181 parametersΔρmin = −1.11 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[Yb2(C13H21)2I2(C4H10O)2]V = 2040.28 (6) Å3
Mr = 1102.72Z = 2
Monoclinic, P21/nMo Kα
a = 13.7190 (3) ŵ = 6.10 mm−1
b = 11.1690 (1) ÅT = 160 K
c = 14.4440 (3) Å0.40 × 0.30 × 0.15 mm
β = 112.800 (1)º
Data collection top
Bruker SMART 1K CCD
diffractometer		2928 independent reflections
Absorption correction: multi-scan
(XPREP; Sheldrick, 1995)		2679 reflections with I > 2σ(I)
Tmin = 0.192, Tmax = 0.401Rint = 0.033
8321 measured reflectionsθmax = 23.3º
Refinement top
R[F2 > 2σ(F2)] = 0.026181 parameters
wR(F2) = 0.059H-atom parameters constrained
S = 1.09Δρmax = 0.92 e Å−3
2928 reflectionsΔρmin = −1.11 e Å−3
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Yb10.848794 (19)0.48479 (2)0.519907 (18)0.02631 (9)
I10.92348 (3)0.43514 (4)0.34774 (3)0.03074 (12)
O10.7760 (4)0.6781 (4)0.4630 (3)0.0524 (13)
C10.6879 (4)0.3797 (5)0.5476 (4)0.0257 (13)
H10.62040.40750.50900.031*
C20.7543 (4)0.4259 (5)0.6424 (4)0.0262 (13)
C30.8486 (4)0.3596 (5)0.6738 (4)0.0231 (12)
H30.90670.37070.73360.028*
C40.8410 (4)0.2731 (5)0.5998 (4)0.0238 (12)
H40.89310.21830.60270.029*
C50.7402 (4)0.2844 (5)0.5203 (4)0.0240 (12)
C60.6922 (5)0.2019 (5)0.4301 (4)0.0310 (14)
C70.6089 (5)0.1221 (6)0.4471 (5)0.0444 (17)
H7A0.55480.17150.45380.067*
H7B0.64210.07580.50720.067*
H7C0.57790.06920.39090.067*
C80.7764 (5)0.1225 (6)0.4175 (5)0.0416 (16)
H8A0.74370.06810.36270.062*
H8B0.81190.07800.47810.062*
H8C0.82670.17140.40370.062*
C90.6382 (5)0.2726 (6)0.3338 (4)0.0351 (15)
H9A0.68950.32100.32110.053*
H9B0.58480.32320.34060.053*
H9C0.60610.21830.27880.053*
C100.7263 (5)0.5216 (5)0.7035 (4)0.0314 (14)
C110.6980 (7)0.4584 (7)0.7850 (6)0.058 (2)
H11A0.68630.51740.82800.088*
H11B0.75510.40690.82420.088*
H11C0.63500.41170.75360.088*
C120.8200 (5)0.6051 (6)0.7574 (5)0.0460 (17)
H12A0.84000.64530.70870.069*
H12B0.87870.55890.80150.069*
H12C0.80010.66310.79580.069*
C130.6325 (6)0.5959 (8)0.6373 (6)0.063 (2)
H13A0.64930.63450.58600.095*
H13B0.61660.65530.67740.095*
H13C0.57220.54470.60670.095*
C140.6291 (11)0.6154 (14)0.3336 (11)0.168 (8)
H14A0.57070.64180.27490.251*
H14B0.60300.57900.37970.251*
H14C0.67010.55800.31450.251*
C150.6885 (9)0.7070 (13)0.3767 (9)0.117 (4)
H15A0.64590.76530.39390.140*
H15B0.71290.74430.32890.140*
C160.8367 (7)0.7862 (7)0.5083 (6)0.061 (2)
H16A0.88180.76930.57760.073*
H16B0.78800.84910.50830.073*
C170.9034 (7)0.8298 (8)0.4551 (7)0.075 (3)
H17A0.94090.90030.48790.112*
H17B0.85920.84850.38680.112*
H17C0.95300.76870.45620.112*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Yb10.02713 (15)0.02691 (15)0.02587 (15)−0.00026 (11)0.01133 (11)0.00181 (11)
I10.0296 (2)0.0388 (2)0.0227 (2)−0.00659 (17)0.00885 (16)−0.00354 (17)
O10.058 (3)0.056 (3)0.045 (3)0.023 (3)0.021 (2)0.022 (3)
C10.019 (3)0.033 (3)0.021 (3)0.002 (3)0.004 (2)0.002 (3)
C20.029 (3)0.025 (3)0.025 (3)0.000 (3)0.011 (3)0.001 (3)
C30.025 (3)0.025 (3)0.017 (3)−0.002 (2)0.006 (2)0.003 (2)
C40.023 (3)0.024 (3)0.024 (3)0.000 (2)0.009 (2)0.002 (2)
C50.024 (3)0.025 (3)0.025 (3)−0.002 (2)0.011 (2)−0.001 (2)
C60.035 (3)0.028 (3)0.025 (3)−0.008 (3)0.006 (3)−0.005 (3)
C70.051 (4)0.047 (4)0.031 (3)−0.021 (3)0.010 (3)−0.004 (3)
C80.047 (4)0.034 (4)0.039 (4)0.000 (3)0.012 (3)−0.014 (3)
C90.036 (3)0.042 (4)0.024 (3)−0.009 (3)0.007 (3)−0.005 (3)
C100.034 (3)0.034 (3)0.031 (3)0.006 (3)0.018 (3)0.000 (3)
C110.090 (6)0.046 (4)0.067 (5)−0.012 (4)0.060 (5)−0.010 (4)
C120.049 (4)0.044 (4)0.049 (4)−0.013 (4)0.023 (3)−0.016 (3)
C130.057 (5)0.071 (6)0.056 (5)0.035 (4)0.015 (4)−0.013 (4)
C140.122 (11)0.171 (15)0.141 (12)−0.067 (11)−0.024 (9)0.081 (12)
C150.087 (8)0.138 (12)0.091 (8)0.016 (8)−0.004 (7)0.041 (8)
C160.090 (6)0.036 (4)0.072 (5)0.020 (4)0.047 (5)0.009 (4)
C170.087 (6)0.065 (6)0.096 (7)0.017 (5)0.060 (6)0.014 (5)
Geometric parameters (Å, °) top
Yb1—Cp2.37C8—H8B0.9600
Yb1—O12.387 (5)C8—H8C0.9600
Yb1—C32.627 (5)C9—H9A0.9600
Yb1—C22.650 (5)C9—H9B0.9600
Yb1—C42.651 (5)C9—H9C0.9600
Yb1—C12.663 (5)C10—C131.519 (9)
Yb1—C52.690 (5)C10—C121.533 (9)
Yb1—I13.0848 (4)C10—C111.547 (9)
Yb1—I1i3.0961 (5)C11—H11A0.9600
I1—Yb1i3.0961 (5)C11—H11B0.9600
O1—C151.393 (10)C11—H11C0.9600
O1—C161.469 (9)C12—H12A0.9600
C1—C21.416 (8)C12—H12B0.9600
C1—C51.422 (8)C12—H12C0.9600
C1—H10.9300C13—H13A0.9600
C2—C31.405 (8)C13—H13B0.9600
C2—C101.526 (8)C13—H13C0.9600
C3—C41.413 (7)C14—C151.306 (16)
C3—H30.9300C14—H14A0.9600
C4—C51.419 (7)C14—H14B0.9600
C4—H40.9300C14—H14C0.9600
C5—C61.522 (8)C15—H15A0.9700
C6—C91.519 (8)C15—H15B0.9700
C6—C81.521 (8)C16—C171.486 (10)
C6—C71.543 (8)C16—H16A0.9700
C7—H7A0.9600C16—H16B0.9700
C7—H7B0.9600C17—H17A0.9600
C7—H7C0.9600C17—H17B0.9600
C8—H8A0.9600C17—H17C0.9600
I1—Yb1—Cp127C8—C6—C7109.0 (5)
O1—Yb1—Cp124C5—C6—C7108.3 (5)
I1—Yb1—Cpi115C6—C7—H7A109.5
O1—Yb1—C3129.45 (16)C6—C7—H7B109.5
O1—Yb1—C2101.92 (16)H7A—C7—H7B109.5
C3—Yb1—C230.87 (17)C6—C7—H7C109.5
O1—Yb1—C4150.96 (16)H7A—C7—H7C109.5
C3—Yb1—C431.06 (16)H7B—C7—H7C109.5
C2—Yb1—C451.34 (17)C6—C8—H8A109.5
O1—Yb1—C1100.94 (17)C6—C8—H8B109.5
C3—Yb1—C150.62 (17)H8A—C8—H8B109.5
C2—Yb1—C130.92 (17)C6—C8—H8C109.5
C4—Yb1—C150.65 (17)H8A—C8—H8C109.5
O1—Yb1—C5126.52 (17)H8B—C8—H8C109.5
C3—Yb1—C551.15 (17)C6—C9—H9A109.5
C2—Yb1—C551.49 (17)C6—C9—H9B109.5
C4—Yb1—C530.81 (16)H9A—C9—H9B109.5
C1—Yb1—C530.80 (16)C6—C9—H9C109.5
O1—Yb1—I196.34 (11)H9A—C9—H9C109.5
C3—Yb1—I1134.10 (12)H9B—C9—H9C109.5
C2—Yb1—I1153.51 (12)C13—C10—C2111.1 (5)
C4—Yb1—I1105.83 (12)C13—C10—C12109.1 (6)
C1—Yb1—I1126.53 (12)C2—C10—C12111.7 (5)
C5—Yb1—I1102.10 (11)C13—C10—C11109.1 (6)
O1—Yb1—I1i97.98 (13)C2—C10—C11108.3 (5)
C3—Yb1—I1i87.89 (12)C12—C10—C11107.4 (5)
C2—Yb1—I1i107.27 (12)C10—C11—H11A109.5
C4—Yb1—I1i100.96 (11)C10—C11—H11B109.5
C1—Yb1—I1i136.99 (11)H11A—C11—H11B109.5
C5—Yb1—I1i131.77 (12)C10—C11—H11C109.5
I1—Yb1—I1i88.782 (12)H11A—C11—H11C109.5
Yb1—I1—Yb1i91.218 (11)H11B—C11—H11C109.5
C15—O1—C16110.6 (8)C10—C12—H12A109.5
C15—O1—Yb1128.2 (7)C10—C12—H12B109.5
C16—O1—Yb1120.1 (4)H12A—C12—H12B109.5
C2—C1—C5109.7 (5)C10—C12—H12C109.5
C2—C1—Yb174.0 (3)H12A—C12—H12C109.5
C5—C1—Yb175.6 (3)H12B—C12—H12C109.5
C2—C1—H1125.2C10—C13—H13A109.5
C5—C1—H1125.2C10—C13—H13B109.5
Yb1—C1—H1117.0H13A—C13—H13B109.5
C3—C2—C1106.6 (5)C10—C13—H13C109.5
C3—C2—C10126.1 (5)H13A—C13—H13C109.5
C1—C2—C10127.1 (5)H13B—C13—H13C109.5
C3—C2—Yb173.7 (3)C15—C14—H14A109.5
C1—C2—Yb175.1 (3)C15—C14—H14B109.5
C10—C2—Yb1120.7 (4)H14A—C14—H14B109.5
C2—C3—C4109.1 (5)C15—C14—H14C109.5
C2—C3—Yb175.5 (3)H14A—C14—H14C109.5
C4—C3—Yb175.4 (3)H14B—C14—H14C109.5
C2—C3—H3125.4C14—C15—O1114.0 (11)
C4—C3—H3125.4C14—C15—H15A108.7
Yb1—C3—H3115.7O1—C15—H15A108.7
C3—C4—C5108.3 (5)C14—C15—H15B108.7
C3—C4—Yb173.5 (3)O1—C15—H15B108.7
C5—C4—Yb176.1 (3)H15A—C15—H15B107.6
C3—C4—H4125.8O1—C16—C17113.3 (6)
C5—C4—H4125.8O1—C16—H16A108.9
Yb1—C4—H4116.6C17—C16—H16A108.9
C4—C5—C1106.3 (5)O1—C16—H16B108.9
C4—C5—C6127.0 (5)C17—C16—H16B108.9
C1—C5—C6126.4 (5)H16A—C16—H16B107.7
C4—C5—Yb173.1 (3)C16—C17—H17A109.5
C1—C5—Yb173.6 (3)C16—C17—H17B109.5
C6—C5—Yb1123.9 (3)H17A—C17—H17B109.5
C9—C6—C8108.5 (5)C16—C17—H17C109.5
C9—C6—C5111.4 (5)H17A—C17—H17C109.5
C8—C6—C5111.0 (5)H17B—C17—H17C109.5
C9—C6—C7108.5 (5)
Symmetry codes: (i) −x+2, −y+1, −z+1.
Table 1
Selected geometric parameters (Å, °) top
Yb1—Cp2.37Yb1—I13.0848 (4)
Yb1—O12.387 (5)Yb1—I1i3.0961 (5)
I1—Yb1—Cp127O1—Yb1—I1i97.98 (13)
O1—Yb1—Cp124I1—Yb1—I1i88.782 (12)
I1—Yb1—Cpi115Yb1—I1—Yb1i91.218 (11)
O1—Yb1—I196.34 (11)
Symmetry codes: (i) −x+2, −y+1, −z+1.
Acknowledgements top

This work was supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Chemical Sciences Division of the US Department of Energy under contract No. DE—AC03–76SF00098. The author thanks Dr Frederick J. Hollander (at CHEXRAY, the University of California at Berkeley X-ray diffraction facility) for assistance with the crystallography, and Professor Richard A. Andersen.

references
References top

Altomare, A., Cascarano, G., Giacovazzo, C., Guagliardi, A., Burla, M. C., Polidori, G. & Camalli, M. (1994). J. Appl. Cryst. 27, 435–?.

Constantine, S. P., De Lima, G. M., Hitchcock, P. B., Keates, J. M. & Lawless, G. A. (1996). Chem. Commun. pp. 2421–2422.

Schultz, M., Burns, C. J., Schwartz, D. J. & Andersen, R. A. (2000). Organometallics, 19, 781–789.

Schumann, H., Winterfeld, J., Hemling, H. & Kuhn, N. (1993). Chem. Ber. 126, 2657–2659.

Sheldrick, G. M. (1995). XPREP. Version 5.03. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.

Sheldrick, G. M. (1997). SHELXL97. University of Göttingen, Germany.

Sheldrick, G. M. (1998). SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.

Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.

Trifonov, A. T., Spaniol, T. P. & Okuda, J. (2003). Eur. J. Inorg. Chem. pp. 926–935.