metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Di-μ-tert-butanolato-bis­­[bis­­(η5-cyclo­penta­dien­yl)erbium(III)]

aDepartment Chemie und Biochemie, Ludwig-Maximilians-Universität München, Lehrstuhl für Anorganische Festkörperchemie, Butenandtstrasse 5–13 (D), D-81377 München, Germany
*Correspondence e-mail: wolfgang.schnick@uni-muenchen.de

(Received 7 February 2008; accepted 11 February 2008; online 15 February 2008)

In the centrosymmetric title compound, [Er2(C5H5)4(C4H9O)2], each Er atom is in a distorted tetra­hedral coordination environment, coordinated by two cyclo­penta­dienyl rings and two tert-but­oxy groups, forming a dimeric complex bridged through the tert-but­oxy groups.

Related literature

During our search for highly reactive mol­ecular precursors, we characterized a series of lanthanide amide (Baisch, Pagano, Zeuner, Barros et al., 2006[Baisch, U., Pagano, S., Zeuner, M., Barros, N., Maron, L. & Schnick, W. (2006). Chem. Eur. J. 12, 4785-4798.]) and carbamate complexes (Baisch, Pagano, Zeuner & Schnick, 2006[Baisch, U., Pagano, S., Zeuner, M. & Schnick, W. (2006). Eur. J. Inorg. Chem. pp. 3517-3524.]). The synthesis of [Er2{μ-η1:η2-OC(OBut)NH}Cp4] and its application as a precursor is described by Zeuner et al. (2008[Zeuner, M., Pagano, S. & Schnick, W. (2008). Chem. Eur. J. 14, 1524-1531.]). For related literature and a general overview of cyclo­penta­dienyl-containing compounds of the lanthanides, see: Schumann et al. (1995[Schumann, H., Messe-Marktscheffel, J. A. & Esser, L. (1995). Chem. Rev. 95, 865-986.]).

[Scheme 1]

Experimental

Crystal data
  • [Er2(C5H5)4(C4H9O)2]

  • Mr = 741.10

  • Monoclinic, P 21 /n

  • a = 8.3905 (17) Å

  • b = 15.628 (3) Å

  • c = 9.950 (2) Å

  • β = 101.85 (3)°

  • V = 1276.9 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 6.55 mm−1

  • T = 200 (2) K

  • 0.13 × 0.07 × 0.04 mm

Data collection
  • Nonius KappaCCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001[Sheldrick, G. M. (2001). SADABS. Version 2. University of Göttingen, Germany.]) Tmin = 0.594, Tmax = 0.783

  • 5666 measured reflections

  • 2912 independent reflections

  • 2578 reflections with I > \2s(I)

  • Rint = 0.021

Refinement
  • R[F2 > 2σ(F2)] = 0.022

  • wR(F2) = 0.053

  • S = 1.05

  • 2912 reflections

  • 149 parameters

  • H-atom parameters constrained

  • Δρmax = 1.29 e Å−3

  • Δρmin = −1.23 e Å−3

Data collection: COLLECT (Nonius, 2004[Nonius (2004). COLLECT. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: DIAMOND (Brandenburg 1999[Brandenburg, K. (1999). DIAMOND. Release 2.1c. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

By stirring [Er2{µ-η1:η2-OC(OBut)NH}Cp4] in THF the carbamato moiety decomposes to [Cp2ErtBuO]2 and an amorphous solid showing strong C=N vibrations (2190 cm-1) in the IR spectra. It is likely that the tert-butylcarbamato ligand splits up into tert-butanol and cyanate. Attempts to isolate a crystalline cyanato complex were unsuccessful as yet. The structure of [Cp2ErtBuO]2 is in accordance with a series of lanthanide-cyclopentadienyl-alcoholate-complexes synthesized so far (Schumann et al., 1995).

Related literature top

During our search for highly reactive molecular precursors, we characterized a series of lanthanide amide- (Baisch, Pagano, Zeuner, Barros et al., 2006) and carbamate complexes (Baisch, Pagano, Zeuner & Schnick, 2006). The synthesis of [Er2{µ-η1:η2-OC(OBut)NH}Cp4] and its application as a precursor is described by Zeuner et al. (2008). For related literature and a general overview on cyclopentadienyl-containing compounds of the lanthanides, see Schumann et al. (1995).

Experimental top

[Er2{µ-η1:η2-OC(OBut)NH}Cp4] was dissolved in dry THF and stirred for 12 h at 297 K. After evaporation of the solvent the orange residue was suspended in dry hexane. The filtrate was stored at 279 K to afford [Cp2ErtBuO]2 as pink crystals.

Refinement top

The H atoms were positioned geometrically and refined using a riding model: C(aromatic)–H = 0.95 Å with Uiso(H) = 1.2Ueq(C), and C(aliphatic)–H = 0.98 Å with Uiso(H) = 1.5Ueq(C).

Computing details top

Data collection: COLLLECT (Nonius, 2004); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. A view of the title compound showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H– atoms are omitted for clarity.
[Figure 2] Fig. 2. Crystal packing diagram of the title compound viewed along the a axis.
Di-µ-tert-butanolato-bis[bis(η5-cyclopentadienyl)erbium(III)] top
Crystal data top
[Er2(C5H5)4(C4H9O)2]F(000) = 716
Mr = 741.10Dx = 1.928 Mg m3
Monoclinic, P21/nMelting point: not measured K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 8.3905 (17) ÅCell parameters from 14322 reflections
b = 15.628 (3) Åθ = 3.1–27.5°
c = 9.950 (2) ŵ = 6.55 mm1
β = 101.85 (3)°T = 200 K
V = 1276.9 (5) Å3Block, pink
Z = 20.13 × 0.07 × 0.04 mm
Data collection top
Nonius KappaCCD
diffractometer
2912 independent reflections
Radiation source: fine-focus sealed tube2578 reflections with I > \2s(I)
Graphite monochromatorRint = 0.021
Detector resolution: 9 pixels mm-1θmax = 27.5°, θmin = 3.2°
ϕ and ω scansh = 1010
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)
k = 2020
Tmin = 0.594, Tmax = 0.783l = 1212
5666 measured reflections
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)] = 0.022H-atom parameters constrained
wR(F2) = 0.053 w = 1/[σ2(Fo2) + (0.025P)2 + 1.7644P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max = 0.002
2912 reflectionsΔρmax = 1.29 e Å3
149 parametersΔρmin = 1.23 e Å3
0 restraintsExtinction correction: (SHELXL97; Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0022 (2)
Crystal data top
[Er2(C5H5)4(C4H9O)2]V = 1276.9 (5) Å3
Mr = 741.10Z = 2
Monoclinic, P21/nMo Kα radiation
a = 8.3905 (17) ŵ = 6.55 mm1
b = 15.628 (3) ÅT = 200 K
c = 9.950 (2) Å0.13 × 0.07 × 0.04 mm
β = 101.85 (3)°
Data collection top
Nonius KappaCCD
diffractometer
2912 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)
2578 reflections with I > \2s(I)
Tmin = 0.594, Tmax = 0.783Rint = 0.021
5666 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0220 restraints
wR(F2) = 0.053H-atom parameters constrained
S = 1.05Δρmax = 1.29 e Å3
2912 reflectionsΔρmin = 1.23 e Å3
149 parameters
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
Er10.080747 (15)0.036095 (8)0.666673 (13)0.01748 (7)
C150.2668 (4)0.0762 (3)0.8373 (4)0.0332 (8)
H150.21310.11760.88210.040*
C130.3898 (5)0.0464 (3)0.7888 (5)0.0385 (9)
H130.43310.10280.79530.046*
C230.0655 (5)0.0983 (3)0.8573 (4)0.0396 (10)
H230.06830.06050.93150.048*
C250.1323 (5)0.1661 (2)0.6539 (4)0.0328 (8)
H250.18870.18350.56530.039*
C210.0166 (5)0.1986 (2)0.7245 (4)0.0349 (8)
H210.07970.24140.69190.042*
C110.3101 (4)0.0858 (3)0.7084 (4)0.0312 (8)
H110.29060.13500.65130.037*
C220.0565 (5)0.1574 (3)0.8508 (4)0.0376 (9)
H220.15050.16790.92030.045*
C140.3175 (5)0.0055 (3)0.8874 (4)0.0391 (9)
H140.30530.02900.97280.047*
C120.3865 (4)0.0107 (3)0.6790 (4)0.0339 (8)
H120.42880.00010.59900.041*
C240.1835 (5)0.1041 (3)0.7358 (4)0.0375 (9)
H240.28090.07150.71340.045*
O10.0788 (3)0.06891 (14)0.4454 (2)0.0195 (4)
C10.1512 (4)0.1414 (2)0.3870 (3)0.0246 (7)
C20.0347 (5)0.2174 (2)0.3640 (4)0.0343 (8)
H2A0.06650.20070.30140.051*
H2B0.08530.26490.32380.051*
H2C0.01060.23540.45200.051*
C40.1903 (5)0.1155 (2)0.2497 (4)0.0328 (8)
H4A0.27190.06980.26420.049*
H4B0.23310.16510.20820.049*
H4C0.09100.09510.18830.049*
C30.3083 (5)0.1691 (3)0.4829 (4)0.0360 (9)
H3A0.28630.18200.57370.054*
H3B0.35120.22030.44570.054*
H3C0.38860.12280.49080.054*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Er10.01723 (10)0.01828 (10)0.01704 (10)0.00043 (5)0.00380 (6)0.00140 (5)
C150.0310 (19)0.038 (2)0.0284 (19)0.0078 (16)0.0010 (14)0.0104 (16)
C130.0205 (18)0.041 (2)0.049 (2)0.0049 (15)0.0040 (16)0.0010 (19)
C230.058 (3)0.035 (2)0.033 (2)0.0116 (19)0.0257 (19)0.0020 (17)
C250.038 (2)0.0274 (19)0.033 (2)0.0108 (16)0.0053 (15)0.0065 (15)
C210.045 (2)0.0218 (18)0.042 (2)0.0023 (16)0.0192 (17)0.0102 (16)
C110.0268 (18)0.036 (2)0.0295 (19)0.0109 (15)0.0022 (14)0.0029 (15)
C220.042 (2)0.038 (2)0.031 (2)0.0075 (17)0.0030 (16)0.0179 (17)
C140.031 (2)0.054 (3)0.0276 (19)0.0070 (19)0.0043 (15)0.0051 (19)
C120.0188 (17)0.049 (2)0.035 (2)0.0079 (16)0.0079 (14)0.0053 (18)
C240.0297 (19)0.030 (2)0.058 (3)0.0028 (16)0.0221 (18)0.0096 (19)
O10.0228 (11)0.0165 (11)0.0196 (11)0.0040 (9)0.0050 (8)0.0020 (9)
C10.0294 (17)0.0178 (16)0.0278 (17)0.0054 (13)0.0088 (13)0.0026 (13)
C20.045 (2)0.0182 (17)0.042 (2)0.0002 (16)0.0144 (17)0.0095 (16)
C40.042 (2)0.0291 (19)0.0300 (18)0.0063 (16)0.0147 (15)0.0041 (16)
C30.040 (2)0.033 (2)0.036 (2)0.0147 (17)0.0101 (16)0.0002 (17)
Geometric parameters (Å, º) top
Er1—O12.257 (2)C25—H250.9500
Er1—O1i2.262 (2)C21—C221.390 (6)
Er1—C132.633 (4)C21—H210.9500
Er1—C122.646 (3)C11—C121.397 (6)
Er1—C232.646 (4)C11—H110.9500
Er1—C242.673 (3)C22—H220.9500
Er1—C222.673 (4)C14—H140.9500
Er1—C112.679 (4)C12—H120.9500
Er1—C212.682 (4)C24—H240.9500
Er1—C142.685 (4)O1—C11.461 (4)
Er1—C252.692 (4)O1—Er1i2.262 (2)
Er1—C152.705 (4)C1—C31.523 (5)
C15—C141.405 (6)C1—C41.524 (5)
C15—C111.411 (5)C1—C21.525 (5)
C15—H150.9500C2—H2A0.9800
C13—C121.406 (6)C2—H2B0.9800
C13—C141.409 (6)C2—H2C0.9800
C13—H130.9500C4—H4A0.9800
C23—C221.391 (6)C4—H4B0.9800
C23—C241.399 (6)C4—H4C0.9800
C23—H230.9500C3—H3A0.9800
C25—C241.391 (6)C3—H3B0.9800
C25—C211.397 (5)C3—H3C0.9800
O1—Er1—O1i78.39 (8)Er1—C13—H13114.5
O1—Er1—C13104.21 (12)C22—C23—C24108.3 (4)
O1i—Er1—C13134.35 (11)C22—C23—Er175.9 (2)
O1—Er1—C1285.46 (10)C24—C23—Er175.8 (2)
O1i—Er1—C12107.00 (11)C22—C23—H23125.8
C13—Er1—C1230.90 (13)C24—C23—H23125.8
O1—Er1—C23134.74 (11)Er1—C23—H23114.7
O1i—Er1—C23107.78 (11)C24—C25—C21108.1 (4)
C13—Er1—C23101.80 (14)C24—C25—Er174.2 (2)
C12—Er1—C23131.01 (13)C21—C25—Er174.6 (2)
O1—Er1—C24108.69 (11)C24—C25—H25126.0
O1i—Er1—C2488.69 (11)C21—C25—H25126.0
C13—Er1—C24130.34 (14)Er1—C25—H25117.3
C12—Er1—C24160.99 (13)C22—C21—C25108.2 (4)
C23—Er1—C2430.49 (13)C22—C21—Er174.6 (2)
O1—Er1—C22121.39 (11)C25—C21—Er175.3 (2)
O1i—Er1—C22137.07 (11)C22—C21—H21125.9
C13—Er1—C2281.17 (13)C25—C21—H21125.9
C12—Er1—C22111.94 (13)Er1—C21—H21116.3
C23—Er1—C2230.31 (13)C12—C11—C15108.5 (4)
C24—Er1—C2250.05 (13)C12—C11—Er173.5 (2)
O1—Er1—C11100.02 (10)C15—C11—Er175.8 (2)
O1i—Er1—C1183.92 (11)C12—C11—H11125.8
C13—Er1—C1150.50 (13)C15—C11—H11125.8
C12—Er1—C1130.41 (12)Er1—C11—H11116.9
C23—Er1—C11125.04 (12)C21—C22—C23107.8 (4)
C24—Er1—C11148.22 (12)C21—C22—Er175.3 (2)
C22—Er1—C11123.46 (12)C23—C22—Er173.8 (2)
O1—Er1—C2191.86 (10)C21—C22—H22126.1
O1i—Er1—C21131.93 (10)C23—C22—H22126.1
C13—Er1—C2193.72 (13)Er1—C22—H22116.9
C12—Er1—C21119.13 (13)C15—C14—C13107.9 (4)
C23—Er1—C2149.88 (12)C15—C14—Er175.7 (2)
C24—Er1—C2149.84 (12)C13—C14—Er172.6 (2)
C22—Er1—C2130.08 (12)C15—C14—H14126.0
C11—Er1—C21144.01 (12)C13—C14—H14126.0
O1—Er1—C14133.98 (11)Er1—C14—H14117.7
O1i—Er1—C14122.53 (12)C11—C12—C13107.9 (3)
C13—Er1—C1430.70 (14)C11—C12—Er176.1 (2)
C12—Er1—C1450.61 (12)C13—C12—Er174.0 (2)
C23—Er1—C1481.56 (13)C12—C12—H12126.1
C24—Er1—C14111.95 (13)C13—C12—H12126.1
C22—Er1—C1473.34 (13)Er1—C12—H12116.0
C11—Er1—C1450.14 (13)C25—C24—C23107.6 (4)
C21—Er1—C1498.07 (13)C25—C24—Er175.8 (2)
O1—Er1—C2584.86 (10)C23—C24—Er173.7 (2)
O1i—Er1—C25101.80 (10)C25—C24—H24126.2
C13—Er1—C25123.85 (13)C23—C24—H24126.2
C12—Er1—C25147.00 (13)Er1—C24—H24116.5
C23—Er1—C2549.88 (12)C1—O1—Er1130.07 (19)
C24—Er1—C2530.06 (12)C1—O1—Er1i128.22 (18)
C22—Er1—C2549.74 (12)Er1—O1—Er1i101.61 (8)
C11—Er1—C25173.19 (12)O1—C1—C3110.4 (3)
C21—Er1—C2530.13 (12)O1—C1—C4109.6 (3)
C14—Er1—C25123.08 (13)C3—C1—C4108.6 (3)
O1—Er1—C15130.36 (10)O1—C1—C2110.9 (3)
O1i—Er1—C1592.60 (11)C3—C1—C2108.6 (3)
C13—Er1—C1550.45 (13)C4—C1—C2108.7 (3)
C12—Er1—C1550.39 (12)C1—C2—H2A109.5
C23—Er1—C1594.67 (12)C1—C2—H2B109.5
C24—Er1—C15119.92 (13)H2A—C2—H2B109.5
C22—Er1—C1598.37 (12)C1—C2—H2C109.5
C11—Er1—C1530.38 (11)H2A—C2—H2C109.5
C21—Er1—C15126.53 (12)H2B—C2—H2C109.5
C14—Er1—C1530.22 (14)C1—C4—H4A109.5
C25—Er1—C15144.28 (12)C1—C4—H4B109.5
C14—C15—C11107.6 (4)H4A—C4—H4B109.5
C14—C15—Er174.1 (2)C1—C4—H4C109.5
C11—C15—Er173.8 (2)H4A—C4—H4C109.5
C14—C15—H15126.2H4B—C4—H4C109.5
C11—C15—H15126.2C1—C3—H3A109.5
Er1—C15—H15117.9C1—C3—H3B109.5
C12—C13—C14108.1 (4)H3A—C3—H3B109.5
C12—C13—Er175.1 (2)C1—C3—H3C109.5
C14—C13—Er176.7 (2)H3A—C3—H3C109.5
C12—C13—H13125.9H3B—C3—H3C109.5
C14—C13—H13125.9
Symmetry code: (i) x, y, z+1.

Experimental details

Crystal data
Chemical formula[Er2(C5H5)4(C4H9O)2]
Mr741.10
Crystal system, space groupMonoclinic, P21/n
Temperature (K)200
a, b, c (Å)8.3905 (17), 15.628 (3), 9.950 (2)
β (°) 101.85 (3)
V3)1276.9 (5)
Z2
Radiation typeMo Kα
µ (mm1)6.55
Crystal size (mm)0.13 × 0.07 × 0.04
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2001)
Tmin, Tmax0.594, 0.783
No. of measured, independent and
observed [I > \2s(I)] reflections
5666, 2912, 2578
Rint0.021
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.022, 0.053, 1.05
No. of reflections2912
No. of parameters149
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.29, 1.23

Computer programs: COLLLECT (Nonius, 2004), DENZO/SCALEPACK (Otwinowski & Minor 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg 1999).

 

Acknowledgements

The authors are indebted to Dr Peter Meyer for performing the single-crystal X-ray diffractometry. Financial support by the Deutsche Forschungsgemeinschaft (DFG) (Schwerpunktprogramm SPP 1166, Lanthanoidspezifische Funktionalitäten in Molekül und Material, project SCHN377/10) and the Fonds der Chemischen Industrie is also gratefully acknowledged.

References

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