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

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Crystal structure of 1,1′-bis­­(2-meth­­oxy­carbonyl-2-methyl­prop­yl)ferrocene

aCollege of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu 215123, People's Republic of China, and bKey Laboratory of Eco-textiles, Ministry of Education, College of Textile & Clothing, Jiangnan University, Wuxi 214122, People's Republic of China
*Correspondence e-mail: gaoqiang@jiangnan.edu.cn

Edited by M. Weil, Vienna University of Technology, Austria (Received 26 October 2015; accepted 31 October 2015; online 7 November 2015)

The Fe atom in the title ferrocene derivative, [Fe(C11H15O2)2], is situated on an inversion centre. As a result of the point-group symmetry -1 of the mol­ecule, the ferrocene moiety adopts a staggered conformation. The average Fe—C(Cp) bond length (Cp is cyclo­penta­dien­yl) is 2.045 (4) Å, in agreement with that of other disubstituted ferrocenes. The Fe—C bond length involving the substituted C atom is slightly longer [2.0521 (17) Å] than the remaining Fe—C bond lengths caused by the inductive effect of the methyl­ene group on the Cp ring. Apart from van der Waals forces, no significant inter­molecular inter­actions are observed in the crystal packing.

1. Related literature

The inter­est in disubstituted ferrocene compounds has increased due to their applications in the field of homogeneous catalysis, biology and medicine (Atkinson et al., 2004[Atkinson, R. C. J., Gibson, V. C. & Long, N. J. (2004). Chem. Soc. Rev. 33, 313-328.]; Gao et al., 2009[Gao, L. M., Hernández, R., Matta, J. & Meléndez, E. (2009). Metal-based Drugs, Article ID 420784, doi: 10.1155/2009/420784.]; Ferreira et al., 2006[Ferreira, C. L., Ewart, C. B., Barta, C. A., Little, S., Yardley, V., Martins, C., Polishchuk, E., Smith, P. J., Moss, J. R., Merkel, M., Adam, M. J. & Orvig, C. (2006). Inorg. Chem. 45, 8414-8422.]). The presence of ester groups on these compounds make them promising candidates for the construction of metal-containing polymers (Wilbert et al., 1995[Wilbert, G., Wiesemann, A. & Zentel, R. (1995). Macromol. Chem. Phys. 196, 3771-3788.]). Related structures have been described by Woodward et al. (1952[Woodward, R. B., Rosenblum, M. & Whiting, M. C. (1952). J. Am. Chem. Soc. 74, 3458-3459.]); Cetina et al. (2003[Cetina, M., Jukić, M., Rapić, V. & Golobič, A. (2003). Acta Cryst. C59, m212-m214.]); Navarro et al. (2004[Navarro, A.-E., Spinelli, N., Moustrou, C., Chaix, C., Mandrand, B. & Brisset, H. (2004). Nucleic Acids Res. 32, 5310-5319.]); Pérez et al. (2015[Pérez, W. I., Rheingold, A. L. & Meléndez, E. (2015). Acta Cryst. E71, 536-539.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • [Fe(C11H15O2)2]

  • Mr = 414.31

  • Triclinic, [P \overline 1]

  • a = 6.273 (3) Å

  • b = 8.313 (4) Å

  • c = 10.490 (5) Å

  • α = 83.833 (6)°

  • β = 74.405 (7)°

  • γ = 81.652 (8)°

  • V = 520.0 (4) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.75 mm−1

  • T = 296 K

  • 0.15 × 0.12 × 0.12 mm

2.2. Data collection

  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Krause et al., 2015[Krause, L., Herbst-Irmer, R., Sheldrick, G. M. & Stalke, D. (2015). J. Appl. Cryst. 48, 3-10.]) Tmin = 0.896, Tmax = 0.916

  • 2753 measured reflections

  • 1793 independent reflections

  • 1688 reflections with I > 2σ(I)

  • Rint = 0.013

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.074

  • S = 1.05

  • 1793 reflections

  • 124 parameters

  • H-atom parameters constrained

  • Δρmax = 0.21 e Å−3

  • Δρmin = −0.17 e Å−3

Data collection: APEX2 (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2012[Bruker (2012). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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 & Berndt, 1999[Brandenburg, K. & Berndt, M. (1999). DIAMOND. University of Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]).

Supporting information


Related literature top

The interest in disubstituted ferrocene compounds has increased due to their applications in the field of homogeneous catalysis, biology and medicine (Atkinson et al., 2004; Gao et al., 2009; Ferreira et al., 2006). The presence of ester groups on these compounds make them promising candidates for the construction of metal-containing polymers (Wilbert et al., 1995). Related structures have been described by Woodward et al. (1952); Cetina et al. (2003); Navarro et al. (2004); Pérez et al. (2015).

Experimental top

1,1'-bis(1-methoxy-methyl)ferrocene was first prepared by refluxing 1,1'-bis(hydroxymethyl)ferrocene in methanol and acetic acid (12:1 v/v) for 16 h. Then a solution of 1,1,-bis(1-methoxy-methyl)ferrocene (3.481 g, 12.7 mmol), 1-methoxy-1-(trimethylsiloxy)-2-methyl-1-propene (10.5 ml, 50.8 mmol) and BF3—OEt2 (3.5 ml, 27.9 mmol) in CH2Cl2 (180 ml) was stirred at 195 K for 15 min. The reaction was quenched with a satured solution of NaHCO3 and extracted with CH2Cl2. The organic phases were combined and dried to give a viscous yellow oil, which was chromatographed over a column of silica gel using ethyl acetate/petroleum ether (1:4 v/v) as the eluent. Yellow crystals of the title compound were obtained by slow evaporation of a solution in dichloromethane/petroleum ether (333-363 K). 1H NMR (400 MHz, CDCl3) δ 3.97 (d, 8H, C5H4FeC5H4), 3.62 (s, 6H, OCH3), 2.57 (s, 4H, CH2), 1.08 (s, 12H, C(CH3)2). HRMS (ESI): C22H30FeO4 calcd for [M + H]+ 415.1572, found 415.1575.

Refinement top

H atoms were placed in calculated positions and thereafter treated as riding atoms, with C—H = 0.98 Å and Uiso(H) = 1.2Ueq(C) (Cp rings CH), 0.97 Å and Uiso(H) = 1.2Ueq(C) (methylene CH2) and 0.96 Å Uiso(H) = 1.5Ueq(C) (methyl CH3).

Structure description top

The interest in disubstituted ferrocene compounds has increased due to their applications in the field of homogeneous catalysis, biology and medicine (Atkinson et al., 2004; Gao et al., 2009; Ferreira et al., 2006). The presence of ester groups on these compounds make them promising candidates for the construction of metal-containing polymers (Wilbert et al., 1995). Related structures have been described by Woodward et al. (1952); Cetina et al. (2003); Navarro et al. (2004); Pérez et al. (2015).

Computing details top

Data collection: APEX2 (Bruker, 2012); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Berndt, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title complex, showing displacement ellipsoids drawn at the 50% probability level. All H atoms have been omitted for clarity. Unlabelled atoms are related to labelled ones by the symmetry operation -x, -y + 1, -z + 1.
[Figure 2] Fig. 2. The packing of molecules in the crystal structure of the title compound.
1,1'-Bis(2-methoxycarbonyl-2-methylpropyl)ferrocene top
Crystal data top
[Fe(C11H15O2)2]Z = 1
Mr = 414.31F(000) = 220
Triclinic, P1Dx = 1.323 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.273 (3) ÅCell parameters from 1589 reflections
b = 8.313 (4) Åθ = 3.3–28.2°
c = 10.490 (5) ŵ = 0.75 mm1
α = 83.833 (6)°T = 296 K
β = 74.405 (7)°Block, yellow
γ = 81.652 (8)°0.15 × 0.12 × 0.12 mm
V = 520.0 (4) Å3
Data collection top
Bruker APEXII CCD
diffractometer
1793 independent reflections
Radiation source: fine-focus sealed tube1688 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.013
φ and ω scansθmax = 25.0°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
h = 75
Tmin = 0.896, Tmax = 0.916k = 99
2753 measured reflectionsl = 1212
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.074H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.038P)2 + 0.1517P]
where P = (Fo2 + 2Fc2)/3
1793 reflections(Δ/σ)max = 0.001
124 parametersΔρmax = 0.21 e Å3
0 restraintsΔρmin = 0.17 e Å3
Crystal data top
[Fe(C11H15O2)2]γ = 81.652 (8)°
Mr = 414.31V = 520.0 (4) Å3
Triclinic, P1Z = 1
a = 6.273 (3) ÅMo Kα radiation
b = 8.313 (4) ŵ = 0.75 mm1
c = 10.490 (5) ÅT = 296 K
α = 83.833 (6)°0.15 × 0.12 × 0.12 mm
β = 74.405 (7)°
Data collection top
Bruker APEXII CCD
diffractometer
1793 independent reflections
Absorption correction: multi-scan
(SADABS; Krause et al., 2015)
1688 reflections with I > 2σ(I)
Tmin = 0.896, Tmax = 0.916Rint = 0.013
2753 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.074H-atom parameters constrained
S = 1.05Δρmax = 0.21 e Å3
1793 reflectionsΔρmin = 0.17 e Å3
124 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
Fe10.00000.50000.50000.03254 (14)
O10.6653 (2)0.24987 (19)0.15534 (14)0.0536 (4)
O20.4288 (3)0.2353 (2)0.03404 (15)0.0646 (4)
C80.4892 (3)0.1969 (2)0.13268 (18)0.0397 (4)
C50.1330 (3)0.3282 (2)0.36443 (16)0.0335 (4)
C10.1796 (3)0.4864 (2)0.30665 (17)0.0387 (4)
H1A0.32820.52030.26850.046*
C60.2998 (3)0.1817 (2)0.37491 (17)0.0377 (4)
H6A0.23430.10940.44960.045*
H6B0.42880.21690.39310.045*
C40.1038 (3)0.3335 (2)0.40734 (18)0.0410 (4)
H4A0.18610.24260.45130.049*
C70.3785 (3)0.0848 (2)0.24845 (18)0.0372 (4)
C110.1817 (4)0.0227 (3)0.2186 (2)0.0547 (6)
H11A0.23290.03630.14000.082*
H11B0.07460.11340.20490.082*
H11C0.11340.04820.29200.082*
C100.5508 (4)0.0594 (3)0.2709 (2)0.0519 (5)
H10A0.60120.11970.19300.078*
H10B0.48360.12930.34520.078*
H10C0.67530.01920.28840.078*
C20.0263 (4)0.5867 (3)0.31440 (18)0.0467 (5)
H2A0.04420.70180.28250.056*
C90.7892 (5)0.3576 (3)0.0540 (3)0.0721 (7)
H9A0.91060.38690.08260.108*
H9B0.69250.45420.03870.108*
H9C0.84680.30330.02670.108*
C30.1995 (4)0.4931 (3)0.3759 (2)0.0488 (5)
H3A0.35930.53160.39440.059*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.0326 (2)0.0351 (2)0.0286 (2)0.00167 (15)0.00463 (15)0.00833 (14)
O10.0475 (8)0.0685 (10)0.0448 (8)0.0180 (7)0.0123 (7)0.0122 (7)
O20.0833 (12)0.0734 (11)0.0426 (8)0.0069 (9)0.0298 (8)0.0029 (8)
C80.0437 (11)0.0398 (10)0.0332 (10)0.0076 (8)0.0094 (8)0.0109 (8)
C50.0359 (9)0.0366 (9)0.0269 (8)0.0039 (7)0.0040 (7)0.0089 (7)
C10.0447 (11)0.0408 (10)0.0270 (9)0.0049 (8)0.0019 (8)0.0060 (7)
C60.0409 (10)0.0396 (10)0.0306 (9)0.0009 (8)0.0075 (8)0.0034 (7)
C40.0371 (10)0.0479 (11)0.0395 (10)0.0079 (8)0.0069 (8)0.0138 (8)
C70.0375 (10)0.0338 (9)0.0394 (10)0.0018 (8)0.0098 (8)0.0073 (8)
C110.0513 (12)0.0519 (13)0.0651 (14)0.0067 (10)0.0150 (11)0.0224 (11)
C100.0533 (13)0.0396 (11)0.0557 (12)0.0082 (9)0.0100 (10)0.0017 (9)
C20.0610 (13)0.0430 (11)0.0338 (10)0.0073 (10)0.0139 (9)0.0068 (8)
C90.0694 (16)0.0802 (18)0.0595 (15)0.0259 (14)0.0050 (13)0.0195 (13)
C30.0414 (11)0.0622 (13)0.0449 (11)0.0074 (10)0.0155 (9)0.0199 (10)
Geometric parameters (Å, º) top
Fe1—C2i2.043 (2)C6—C71.554 (3)
Fe1—C22.043 (2)C6—H6A0.9700
Fe1—C4i2.044 (2)C6—H6B0.9700
Fe1—C42.044 (2)C4—C31.418 (3)
Fe1—C3i2.044 (2)C4—H4A0.9800
Fe1—C32.044 (2)C7—C111.522 (3)
Fe1—C1i2.0445 (19)C7—C101.536 (3)
Fe1—C12.0445 (19)C11—H11A0.9600
Fe1—C5i2.0521 (17)C11—H11B0.9600
Fe1—C52.0521 (17)C11—H11C0.9600
O1—C81.333 (3)C10—H10A0.9600
O1—C91.446 (3)C10—H10B0.9600
O2—C81.192 (2)C10—H10C0.9600
C8—C71.522 (3)C2—C31.400 (3)
C5—C11.424 (3)C2—H2A0.9800
C5—C41.428 (3)C9—H9A0.9600
C5—C61.501 (3)C9—H9B0.9600
C1—C21.420 (3)C9—H9C0.9600
C1—H1A0.9800C3—H3A0.9800
C2i—Fe1—C2180.0C2—C1—C5108.24 (18)
C2i—Fe1—C4i67.98 (9)C2—C1—Fe169.61 (10)
C2—Fe1—C4i112.02 (9)C5—C1—Fe169.95 (10)
C2i—Fe1—C4112.02 (9)C2—C1—H1A125.9
C2—Fe1—C467.98 (9)C5—C1—H1A125.9
C4i—Fe1—C4180.0Fe1—C1—H1A125.9
C2i—Fe1—C3i40.08 (9)C5—C6—C7113.97 (15)
C2—Fe1—C3i139.92 (9)C5—C6—H6A108.8
C4i—Fe1—C3i40.61 (8)C7—C6—H6A108.8
C4—Fe1—C3i139.39 (8)C5—C6—H6B108.8
C2i—Fe1—C3139.92 (9)C7—C6—H6B108.8
C2—Fe1—C340.08 (9)H6A—C6—H6B107.7
C4i—Fe1—C3139.39 (8)C3—C4—C5108.21 (18)
C4—Fe1—C340.61 (8)C3—C4—Fe169.70 (12)
C3i—Fe1—C3180.0C5—C4—Fe169.92 (10)
C2i—Fe1—C1i40.65 (8)C3—C4—H4A125.9
C2—Fe1—C1i139.35 (8)C5—C4—H4A125.9
C4i—Fe1—C1i68.18 (8)Fe1—C4—H4A125.9
C4—Fe1—C1i111.82 (8)C11—C7—C8110.12 (17)
C3i—Fe1—C1i68.00 (9)C11—C7—C10109.95 (17)
C3—Fe1—C1i112.00 (9)C8—C7—C10108.85 (16)
C2i—Fe1—C1139.35 (8)C11—C7—C6110.52 (16)
C2—Fe1—C140.65 (8)C8—C7—C6108.53 (15)
C4i—Fe1—C1111.82 (8)C10—C7—C6108.84 (16)
C4—Fe1—C168.18 (8)C7—C11—H11A109.5
C3i—Fe1—C1112.00 (9)C7—C11—H11B109.5
C3—Fe1—C168.00 (9)H11A—C11—H11B109.5
C1i—Fe1—C1180.0C7—C11—H11C109.5
C2i—Fe1—C5i68.48 (8)H11A—C11—H11C109.5
C2—Fe1—C5i111.52 (8)H11B—C11—H11C109.5
C4i—Fe1—C5i40.80 (8)C7—C10—H10A109.5
C4—Fe1—C5i139.20 (8)C7—C10—H10B109.5
C3i—Fe1—C5i68.51 (8)H10A—C10—H10B109.5
C3—Fe1—C5i111.49 (8)C7—C10—H10C109.5
C1i—Fe1—C5i40.67 (7)H10A—C10—H10C109.5
C1—Fe1—C5i139.33 (7)H10B—C10—H10C109.5
C2i—Fe1—C5111.52 (8)C3—C2—C1108.31 (18)
C2—Fe1—C568.48 (8)C3—C2—Fe169.99 (12)
C4i—Fe1—C5139.20 (8)C1—C2—Fe169.73 (11)
C4—Fe1—C540.80 (8)C3—C2—H2A125.8
C3i—Fe1—C5111.49 (8)C1—C2—H2A125.8
C3—Fe1—C568.51 (8)Fe1—C2—H2A125.8
C1i—Fe1—C5139.33 (7)O1—C9—H9A109.5
C1—Fe1—C540.67 (7)O1—C9—H9B109.5
C5i—Fe1—C5180.00 (7)H9A—C9—H9B109.5
C8—O1—C9117.84 (18)O1—C9—H9C109.5
O2—C8—O1123.17 (19)H9A—C9—H9C109.5
O2—C8—C7125.6 (2)H9B—C9—H9C109.5
O1—C8—C7111.19 (16)C2—C3—C4108.28 (18)
C1—C5—C4106.96 (17)C2—C3—Fe169.92 (12)
C1—C5—C6126.84 (17)C4—C3—Fe169.69 (11)
C4—C5—C6126.17 (17)C2—C3—H3A125.9
C1—C5—Fe169.38 (10)C4—C3—H3A125.9
C4—C5—Fe169.28 (10)Fe1—C3—H3A125.9
C6—C5—Fe1127.75 (13)
Symmetry code: (i) x, y+1, z+1.

Experimental details

Crystal data
Chemical formula[Fe(C11H15O2)2]
Mr414.31
Crystal system, space groupTriclinic, P1
Temperature (K)296
a, b, c (Å)6.273 (3), 8.313 (4), 10.490 (5)
α, β, γ (°)83.833 (6), 74.405 (7), 81.652 (8)
V3)520.0 (4)
Z1
Radiation typeMo Kα
µ (mm1)0.75
Crystal size (mm)0.15 × 0.12 × 0.12
Data collection
DiffractometerBruker APEXII CCD
Absorption correctionMulti-scan
(SADABS; Krause et al., 2015)
Tmin, Tmax0.896, 0.916
No. of measured, independent and
observed [I > 2σ(I)] reflections
2753, 1793, 1688
Rint0.013
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.074, 1.05
No. of reflections1793
No. of parameters124
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.21, 0.17

Computer programs: APEX2 (Bruker, 2012), SAINT (Bruker, 2012), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Berndt, 1999), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

We are very grateful for the financial support from the Open Project Program of Key Laboratory of Eco-textiles, Ministry of Education, Jiangnan University (No. KLET1303).

References

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