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

Guo, Y.-F.; Wang, J.-J.; Xu, W.-J.; Sun, D.-H.; Gao, Q.

doi:10.1107/S2056989015020642

metal-organic compounds

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ISSN: 2056-9890

Volume 71| Part 12| December 2015| Pages m213-m214

https://doi.org/10.1107/S2056989015020642

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

Yan-Feng Guo,^a Jian-Jun Wang,^a Wei-Juan Xu,^a Dong-Hao Sun ^a and Qiang Gao ^b ^*

^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.

Keywords: crystal structure; inversion symmetry; disubstituted ferrocene; ester.

CCDC reference: 1434467

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 ; 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 ).

2. Experimental

2.1. Crystal data

[Fe(C₁₁H₁₅O₂)₂]
M_r = 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 ) T_min = 0.896, T_max = 0.916
2753 measured reflections
1793 independent reflections
1688 reflections with I > 2σ(I)
R_int = 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
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Data collection: APEX2 (Bruker, 2012 ); cell refinement: SAINT (Bruker, 2012); data reduction: SAINT; 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).

Supporting information

CCDC reference: 1434467

Crystal structure: contains datablocks I, New_Global_Publ_Block. DOI: https://doi.org/10.1107/S2056989015020642/wm5231sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015020642/wm5231Isup2.hkl

checkCIF report

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.

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

	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.
	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
M_r = 414.31	F(000) = 220
Triclinic, P1	D_x = 1.323 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.273 (3) Å	Cell parameters from 1589 reflections
b = 8.313 (4) Å	θ = 3.3–28.2°
c = 10.490 (5) Å	µ = 0.75 mm⁻¹
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 tube	1688 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.013
φ and ω scans	θ_max = 25.0°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −7→5
T_min = 0.896, T_max = 0.916	k = −9→9
2753 measured reflections	l = −12→12

Refinement top

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.074	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.038P)² + 0.1517P] where P = (F_o² + 2F_c²)/3
1793 reflections	(Δ/σ)_max = 0.001
124 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.17 e Å⁻³

Crystal data top

[Fe(C₁₁H₁₅O₂)₂]	γ = 81.652 (8)°
M_r = 414.31	V = 520.0 (4) Å³
Triclinic, P1	Z = 1
a = 6.273 (3) Å	Mo Kα radiation
b = 8.313 (4) Å	µ = 0.75 mm⁻¹
c = 10.490 (5) Å	T = 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)
T_min = 0.896, T_max = 0.916	R_int = 0.013
2753 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	0 restraints
wR(F²) = 0.074	H-atom parameters constrained
S = 1.05	Δρ_max = 0.21 e Å⁻³
1793 reflections	Δρ_min = −0.17 e Å⁻³
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

	x	y	z	U_iso*/U_eq
Fe1	0.0000	0.5000	0.5000	0.03254 (14)
O1	0.6653 (2)	0.24987 (19)	0.15534 (14)	0.0536 (4)
O2	0.4288 (3)	0.2353 (2)	0.03404 (15)	0.0646 (4)
C8	0.4892 (3)	0.1969 (2)	0.13268 (18)	0.0397 (4)
C5	0.1330 (3)	0.3282 (2)	0.36443 (16)	0.0335 (4)
C1	0.1796 (3)	0.4864 (2)	0.30665 (17)	0.0387 (4)
H1A	0.3282	0.5203	0.2685	0.046*
C6	0.2998 (3)	0.1817 (2)	0.37491 (17)	0.0377 (4)
H6A	0.2343	0.1094	0.4496	0.045*
H6B	0.4288	0.2169	0.3931	0.045*
C4	−0.1038 (3)	0.3335 (2)	0.40734 (18)	0.0410 (4)
H4A	−0.1861	0.2426	0.4513	0.049*
C7	0.3785 (3)	0.0848 (2)	0.24845 (18)	0.0372 (4)
C11	0.1817 (4)	0.0227 (3)	0.2186 (2)	0.0547 (6)
H11A	0.2329	−0.0363	0.1400	0.082*
H11B	0.0746	0.1134	0.2049	0.082*
H11C	0.1134	−0.0482	0.2920	0.082*
C10	0.5508 (4)	−0.0594 (3)	0.2709 (2)	0.0519 (5)
H10A	0.6012	−0.1197	0.1930	0.078*
H10B	0.4836	−0.1293	0.3452	0.078*
H10C	0.6753	−0.0192	0.2884	0.078*
C2	−0.0263 (4)	0.5867 (3)	0.31440 (18)	0.0467 (5)
H2A	−0.0442	0.7018	0.2825	0.056*
C9	0.7892 (5)	0.3576 (3)	0.0540 (3)	0.0721 (7)
H9A	0.9106	0.3869	0.0826	0.108*
H9B	0.6925	0.4542	0.0387	0.108*
H9C	0.8468	0.3033	−0.0267	0.108*
C3	−0.1995 (4)	0.4931 (3)	0.3759 (2)	0.0488 (5)
H3A	−0.3593	0.5316	0.3944	0.059*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Fe1	0.0326 (2)	0.0351 (2)	0.0286 (2)	−0.00167 (15)	−0.00463 (15)	−0.00833 (14)
O1	0.0475 (8)	0.0685 (10)	0.0448 (8)	−0.0180 (7)	−0.0123 (7)	0.0122 (7)
O2	0.0833 (12)	0.0734 (11)	0.0426 (8)	−0.0069 (9)	−0.0298 (8)	0.0029 (8)
C8	0.0437 (11)	0.0398 (10)	0.0332 (10)	0.0076 (8)	−0.0094 (8)	−0.0109 (8)
C5	0.0359 (9)	0.0366 (9)	0.0269 (8)	−0.0039 (7)	−0.0040 (7)	−0.0089 (7)
C1	0.0447 (11)	0.0408 (10)	0.0270 (9)	−0.0049 (8)	−0.0019 (8)	−0.0060 (7)
C6	0.0409 (10)	0.0396 (10)	0.0306 (9)	−0.0009 (8)	−0.0075 (8)	−0.0034 (7)
C4	0.0371 (10)	0.0479 (11)	0.0395 (10)	−0.0079 (8)	−0.0069 (8)	−0.0138 (8)
C7	0.0375 (10)	0.0338 (9)	0.0394 (10)	0.0018 (8)	−0.0098 (8)	−0.0073 (8)
C11	0.0513 (12)	0.0519 (13)	0.0651 (14)	−0.0067 (10)	−0.0150 (11)	−0.0224 (11)
C10	0.0533 (13)	0.0396 (11)	0.0557 (12)	0.0082 (9)	−0.0100 (10)	−0.0017 (9)
C2	0.0610 (13)	0.0430 (11)	0.0338 (10)	0.0073 (10)	−0.0139 (9)	−0.0068 (8)
C9	0.0694 (16)	0.0802 (18)	0.0595 (15)	−0.0259 (14)	−0.0050 (13)	0.0195 (13)
C3	0.0414 (11)	0.0622 (13)	0.0449 (11)	0.0074 (10)	−0.0155 (9)	−0.0199 (10)

Geometric parameters (Å, º) top

Fe1—C2ⁱ	2.043 (2)	C6—C7	1.554 (3)
Fe1—C2	2.043 (2)	C6—H6A	0.9700
Fe1—C4ⁱ	2.044 (2)	C6—H6B	0.9700
Fe1—C4	2.044 (2)	C4—C3	1.418 (3)
Fe1—C3ⁱ	2.044 (2)	C4—H4A	0.9800
Fe1—C3	2.044 (2)	C7—C11	1.522 (3)
Fe1—C1ⁱ	2.0445 (19)	C7—C10	1.536 (3)
Fe1—C1	2.0445 (19)	C11—H11A	0.9600
Fe1—C5ⁱ	2.0521 (17)	C11—H11B	0.9600
Fe1—C5	2.0521 (17)	C11—H11C	0.9600
O1—C8	1.333 (3)	C10—H10A	0.9600
O1—C9	1.446 (3)	C10—H10B	0.9600
O2—C8	1.192 (2)	C10—H10C	0.9600
C8—C7	1.522 (3)	C2—C3	1.400 (3)
C5—C1	1.424 (3)	C2—H2A	0.9800
C5—C4	1.428 (3)	C9—H9A	0.9600
C5—C6	1.501 (3)	C9—H9B	0.9600
C1—C2	1.420 (3)	C9—H9C	0.9600
C1—H1A	0.9800	C3—H3A	0.9800

C2ⁱ—Fe1—C2	180.0	C2—C1—C5	108.24 (18)
C2ⁱ—Fe1—C4ⁱ	67.98 (9)	C2—C1—Fe1	69.61 (10)
C2—Fe1—C4ⁱ	112.02 (9)	C5—C1—Fe1	69.95 (10)
C2ⁱ—Fe1—C4	112.02 (9)	C2—C1—H1A	125.9
C2—Fe1—C4	67.98 (9)	C5—C1—H1A	125.9
C4ⁱ—Fe1—C4	180.0	Fe1—C1—H1A	125.9
C2ⁱ—Fe1—C3ⁱ	40.08 (9)	C5—C6—C7	113.97 (15)
C2—Fe1—C3ⁱ	139.92 (9)	C5—C6—H6A	108.8
C4ⁱ—Fe1—C3ⁱ	40.61 (8)	C7—C6—H6A	108.8
C4—Fe1—C3ⁱ	139.39 (8)	C5—C6—H6B	108.8
C2ⁱ—Fe1—C3	139.92 (9)	C7—C6—H6B	108.8
C2—Fe1—C3	40.08 (9)	H6A—C6—H6B	107.7
C4ⁱ—Fe1—C3	139.39 (8)	C3—C4—C5	108.21 (18)
C4—Fe1—C3	40.61 (8)	C3—C4—Fe1	69.70 (12)
C3ⁱ—Fe1—C3	180.0	C5—C4—Fe1	69.92 (10)
C2ⁱ—Fe1—C1ⁱ	40.65 (8)	C3—C4—H4A	125.9
C2—Fe1—C1ⁱ	139.35 (8)	C5—C4—H4A	125.9
C4ⁱ—Fe1—C1ⁱ	68.18 (8)	Fe1—C4—H4A	125.9
C4—Fe1—C1ⁱ	111.82 (8)	C11—C7—C8	110.12 (17)
C3ⁱ—Fe1—C1ⁱ	68.00 (9)	C11—C7—C10	109.95 (17)
C3—Fe1—C1ⁱ	112.00 (9)	C8—C7—C10	108.85 (16)
C2ⁱ—Fe1—C1	139.35 (8)	C11—C7—C6	110.52 (16)
C2—Fe1—C1	40.65 (8)	C8—C7—C6	108.53 (15)
C4ⁱ—Fe1—C1	111.82 (8)	C10—C7—C6	108.84 (16)
C4—Fe1—C1	68.18 (8)	C7—C11—H11A	109.5
C3ⁱ—Fe1—C1	112.00 (9)	C7—C11—H11B	109.5
C3—Fe1—C1	68.00 (9)	H11A—C11—H11B	109.5
C1ⁱ—Fe1—C1	180.0	C7—C11—H11C	109.5
C2ⁱ—Fe1—C5ⁱ	68.48 (8)	H11A—C11—H11C	109.5
C2—Fe1—C5ⁱ	111.52 (8)	H11B—C11—H11C	109.5
C4ⁱ—Fe1—C5ⁱ	40.80 (8)	C7—C10—H10A	109.5
C4—Fe1—C5ⁱ	139.20 (8)	C7—C10—H10B	109.5
C3ⁱ—Fe1—C5ⁱ	68.51 (8)	H10A—C10—H10B	109.5
C3—Fe1—C5ⁱ	111.49 (8)	C7—C10—H10C	109.5
C1ⁱ—Fe1—C5ⁱ	40.67 (7)	H10A—C10—H10C	109.5
C1—Fe1—C5ⁱ	139.33 (7)	H10B—C10—H10C	109.5
C2ⁱ—Fe1—C5	111.52 (8)	C3—C2—C1	108.31 (18)
C2—Fe1—C5	68.48 (8)	C3—C2—Fe1	69.99 (12)
C4ⁱ—Fe1—C5	139.20 (8)	C1—C2—Fe1	69.73 (11)
C4—Fe1—C5	40.80 (8)	C3—C2—H2A	125.8
C3ⁱ—Fe1—C5	111.49 (8)	C1—C2—H2A	125.8
C3—Fe1—C5	68.51 (8)	Fe1—C2—H2A	125.8
C1ⁱ—Fe1—C5	139.33 (7)	O1—C9—H9A	109.5
C1—Fe1—C5	40.67 (7)	O1—C9—H9B	109.5
C5ⁱ—Fe1—C5	180.00 (7)	H9A—C9—H9B	109.5
C8—O1—C9	117.84 (18)	O1—C9—H9C	109.5
O2—C8—O1	123.17 (19)	H9A—C9—H9C	109.5
O2—C8—C7	125.6 (2)	H9B—C9—H9C	109.5
O1—C8—C7	111.19 (16)	C2—C3—C4	108.28 (18)
C1—C5—C4	106.96 (17)	C2—C3—Fe1	69.92 (12)
C1—C5—C6	126.84 (17)	C4—C3—Fe1	69.69 (11)
C4—C5—C6	126.17 (17)	C2—C3—H3A	125.9
C1—C5—Fe1	69.38 (10)	C4—C3—H3A	125.9
C4—C5—Fe1	69.28 (10)	Fe1—C3—H3A	125.9
C6—C5—Fe1	127.75 (13)

Symmetry code: (i) −x, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	[Fe(C₁₁H₁₅O₂)₂]
M_r	414.31
Crystal system, space group	Triclinic, 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)
V (Å³)	520.0 (4)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	0.75
Crystal size (mm)	0.15 × 0.12 × 0.12

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Krause et al., 2015)
T_min, T_max	0.896, 0.916
No. of measured, independent and observed [I > 2σ(I)] reflections	2753, 1793, 1688
R_int	0.013
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.074, 1.05
No. of reflections	1793
No. of parameters	124
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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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