(2,2-Dichloro­vinyl)ferrocene

Clément, S.; Guyard, L.; Knorr, M.; Gessner, V.H.; Strohmann, C.

doi:10.1107/S1600536809006102

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 3| March 2009| Page m334

doi:10.1107/S1600536809006102

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(2,2-Dichlorovinyl)ferrocene

Sébastien Clément,^a Laurent Guyard,^a Michael Knorr,^a Viktoria H. Gessner ^b and Carsten Strohmann ^b ^*

^aInstitut UTINAM UMR CNRS 6213, Université de Franche-Comté, 16 Route de Gray, La Bouloie, 25030 Besançon, France, and ^bTechnische Universität Dortmund, Anorganische Chemie, Otto-Hahn-Strasse 6, D-44227 Dortmund, Germany
^*Correspondence e-mail: mail@carsten-strohmann.de

(Received 17 February 2009; accepted 19 February 2009; online 28 February 2009)

The title compound, [Fe(C₅H₅)(C₇H₅Cl₂)], represents a versatile building block for the preparation of π-conjugated redox-active compounds or polymetallic organometallic systems due to the presence of the electrochemically active ferrocenyl unit. It is therefore a potential starting material for the preperation of the corresponding alkyne. In the crystal, the alkenyl unit and the cyclopentadienide ring are almost parallel, with an angle between the best planes of only 10.6 (4)°.

Related literature

The title compound was first prepared in 1963, see: Schloegl et al. (1963 ). For an alternative synthesis using a Corey–Fuchs route, see: Luo et al. (2000 ). For the preparation of some other halo-vinyl ferrocenes, see: Naskar et al. (2000 ). For related functionalized ferrocenes, see: Clément et al. (2007a ) and for [2.2]paracyclophanes, see: Clément et al. (2007b ). For the parent compound, ethenylferrocene, see: McAdam et al. (2008 ).

Experimental

Crystal data

[Fe(C₅H₅)(C₇H₅Cl₂)]
M_r = 280.95
Monoclinic, P 2₁ /c
a = 14.340 (3) Å
b = 7.4370 (15) Å
c = 10.932 (2) Å
β = 108.48 (3)°
V = 1105.8 (4) Å³
Z = 4
Mo Kα radiation
μ = 1.81 mm⁻¹
T = 173 K
0.3 × 0.2 × 0.2 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1999 ) T_min = 0.594, T_max = 0.694
3293 measured reflections
1908 independent reflections
1372 reflections with I > 2σ(I)
R_int = 0.05

Refinement

R[F² > 2σ(F²)] = 0.063
wR(F²) = 0.174
S = 1.02
1908 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 1.04 e Å⁻³
Δρ_min = −0.46 e Å⁻³

Data collection: SMART (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS90 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809006102/zl2181sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809006102/zl2181Isup2.hkl

checkCIF report

Comment top

π-Conjugated ligands are widely applied in coordination chemistry, catalysis or polymer sciences. Among them, ethynylferrocene and its derivatives have gained special interest due to their use as building blocks for the synthesis of di- and polymetallic organometallic systems and advanced materials. In the context of our research into developing novel π-conjugated ligands such as functionalized ferrocenes (Clément et al., 2007a) and [2.2]paracyclophanes (Clément et al., 2007b) for potential applications in coordination chemistry, we have recently reported dehalobromation of (2,2-dibromovinyl)ferrocene and dibromovinyl[2.2]paracyclophane as a convenient route to the synthesis of the corresponding alkynes.

In order to take a closer glance on the influence of the halide leaving group in the starting materials {[Cl₂C=C(H)—Fc] versus [Br₂C=C(H)—Fc] (Fc = ferrocenyl)}, we prepared the title compound (2) according to a slightly modified literature procedure (Luo et al., 2000) under Corey-Fuchs conditions by treatment of ferrocenecarbaldehyde (1) with CCl₄ in the presence of zinc dust and triphenyl phosphane (Figure 3).

The molecular structure of 2 is shown in Figure 1. (2,2-Dichlorovinyl)ferrocene (2) crystallizes in the monoclinic crystal system, space group P2₁/c. The two cyclopentadienyl rings are almost eclipsed with a mean cyclopentadienyl twist angle of 6.17°. The dihedral angle between the Cp ring planes is 0.1 (5)°. The bond distance of the vinylic double bond between C(1) and C(2) of 1.321 (9) Å is almost identical with that of (2,2-dibromovinyl)ferrocene [1.318 (4) Å]. The alkenyl unit and the cyclopentadienido ring are fairly coplanar with an angle between the two best planes [(C1 C2 Cl1 Cl2) and (C3 C4 C5 C6 C7)] of only 10.6 (4)°. This value determined for 2 is comparable to that determined for (2,2-dibromovinyl)ferrocene (10.43°) (Clément et al., 2007a). Cl1 is involved in week C–H···Cl interactions (H8···Cl1ⁱ: 2.901 Å and C8–H8···Cl1ⁱ 166.8°; symmetry operator i: x,-y+1/2,+z-1/2). Overall, it seems that the influence of the halide on the molecular geometry is negligeable. In contrast to the parent compound ethenylferrocene (McAdam et al., 2008), where intermolecular C–H···π interactions are present in the solid state, no significant intermolecular interactions are observed in the packing of (2) (Figure 2).

Related literature top

The title compound was first prepared in 1963, see: Schloegl et al. (1963). For an alternative synthesis using a Corey–Fuchs route, see: Luo et al. (2000). For the preparation of some other halo-vinyl ferrocenes, see: Naskar et al. (2000). For related functionalized ferrocenes, see: Clément et al. (2007a) and for [2.2]paracyclophanes, see: Clément et al. (2007b). For the parent compound ethenylferrocene, see: McAdam et al. (2008).

Experimental top

(2,2-Dichlorovinyl)ferrocene (2): Triphenyl phosphane (2.40 g, 8.5 mmol), CCl₄ (0.82 ml, 8.5 mmol) and zinc dust (0.55 g, 8.5 mmol) were placed in a Schlenk tube and 25 ml CH₂Cl₂ were slowly added. After stirring at room temperature for 28 h, ferrocenecarbaldehyde (1) (1.00 g, 4.24 mmol), dissolved in CH₂Cl₂ (10 ml), was added and stirring was continued for further 2 h. The reaction mixture was extracted with three 50 ml portions of pentane and CH₂Cl₂ was added when the reaction mixture became too viscous for further extractions. The extracts were filtered and evaporated under reduced pressure. The crude product was purified by column chromatography on silica gel with CH₂Cl₂/petroleum ether (1:1). Slow evaporation yielded red crystals of 2 (Yield: 91%). Characterization data have been previously described in the literature. (Luo et al., 2000)

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS90 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. ORTEP presentation of (2) at the 30% probability level.
	Fig. 2. Packing diagramm of (2).
	Fig. 3. Synthesis of (2,2-Dichlorovinyl)ferrocene (2) under COREY-FUCHS reaction conditions.

(2,2-Dichlorovinyl)ferrocene top

Crystal data top

[Fe(C₅H₅)(C₇H₅Cl₂)]	F(000) = 568
M_r = 280.95	D_x = 1.688 Mg m⁻³
Monoclinic, P2₁/c	Melting point: 382 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 14.340 (3) Å	Cell parameters from 1338 reflections
b = 7.4370 (15) Å	θ = 1.5–25.0°
c = 10.932 (2) Å	µ = 1.81 mm⁻¹
β = 108.48 (3)°	T = 173 K
V = 1105.8 (4) Å³	Irregular, red
Z = 4	0.3 × 0.2 × 0.2 mm

Data collection top

Bruker APEX CCD diffractometer	1908 independent reflections
Radiation source: fine-focus sealed tube	1372 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.05
ω scans	θ_max = 25.0°, θ_min = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −10→17
T_min = 0.594, T_max = 0.694	k = −8→7
3293 measured reflections	l = −12→11

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)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.174	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0967P)² + 0.0275P] where P = (F_o² + 2F_c²)/3
1908 reflections	(Δ/σ)_max < 0.001
136 parameters	Δρ_max = 1.04 e Å⁻³
0 restraints	Δρ_min = −0.46 e Å⁻³

Crystal data top

[Fe(C₅H₅)(C₇H₅Cl₂)]	V = 1105.8 (4) Å³
M_r = 280.95	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.340 (3) Å	µ = 1.81 mm⁻¹
b = 7.4370 (15) Å	T = 173 K
c = 10.932 (2) Å	0.3 × 0.2 × 0.2 mm
β = 108.48 (3)°

Data collection top

Bruker APEX CCD diffractometer	1908 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1999)	1372 reflections with I > 2σ(I)
T_min = 0.594, T_max = 0.694	R_int = 0.05
3293 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.063	0 restraints
wR(F²) = 0.174	H-atom parameters constrained
S = 1.02	Δρ_max = 1.04 e Å⁻³
1908 reflections	Δρ_min = −0.46 e Å⁻³
136 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
C1	0.3941 (5)	0.1149 (9)	1.0606 (6)	0.0309 (16)
C2	0.3017 (5)	0.0654 (9)	1.0059 (6)	0.0286 (16)
H2	0.2812	−0.0326	1.0468	0.034*
C3	0.2268 (5)	0.1356 (9)	0.8940 (6)	0.0262 (15)
C4	0.2322 (5)	0.2584 (8)	0.7962 (6)	0.0297 (16)
H4	0.2932	0.3182	0.7905	0.036*
C5	0.1361 (6)	0.2818 (9)	0.7090 (7)	0.0339 (17)
H5	0.1177	0.3602	0.6306	0.041*
C6	0.0706 (5)	0.1740 (10)	0.7506 (7)	0.0350 (18)
H6	−0.0018	0.1629	0.7067	0.042*
C7	0.1254 (5)	0.0827 (10)	0.8631 (6)	0.0319 (17)
H7	0.0985	−0.0039	0.9133	0.038*
C8	0.2636 (6)	−0.0694 (10)	0.6107 (7)	0.0389 (19)
H8	0.32	−0.0011	0.5981	0.047*
C9	0.2703 (6)	−0.1880 (10)	0.7137 (8)	0.0372 (18)
H9	0.3317	−0.2198	0.7847	0.045*
C10	0.1753 (5)	−0.2558 (9)	0.6980 (7)	0.0320 (17)
H10	0.1576	−0.343	0.7567	0.038*
C11	0.1090 (5)	−0.1753 (9)	0.5874 (7)	0.0327 (17)
H11	0.0365	−0.1969	0.5529	0.039*
C12	0.1664 (5)	−0.0579 (11)	0.5309 (6)	0.0366 (19)
H12	0.1408	0.0166	0.4511	0.044*
Cl1	0.45229 (14)	0.2850 (3)	1.00576 (19)	0.0410 (5)
Cl2	0.46791 (14)	0.0177 (3)	1.20093 (18)	0.0452 (6)
Fe1	0.17755 (7)	0.01793 (12)	0.71562 (9)	0.0219 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.031 (4)	0.032 (4)	0.022 (4)	0.001 (3)	−0.002 (3)	−0.003 (3)
C2	0.030 (4)	0.029 (4)	0.026 (4)	−0.001 (3)	0.007 (3)	0.000 (3)
C3	0.030 (4)	0.023 (4)	0.021 (3)	0.001 (3)	0.002 (3)	−0.005 (3)
C4	0.034 (4)	0.024 (4)	0.023 (3)	−0.003 (3)	−0.003 (3)	−0.001 (3)
C5	0.039 (4)	0.024 (4)	0.029 (4)	0.007 (3)	−0.002 (3)	−0.006 (3)
C6	0.030 (4)	0.039 (5)	0.034 (4)	0.008 (3)	0.007 (3)	−0.005 (3)
C7	0.036 (4)	0.036 (4)	0.023 (4)	−0.003 (3)	0.009 (3)	−0.007 (3)
C8	0.043 (5)	0.037 (4)	0.041 (5)	−0.004 (4)	0.021 (4)	−0.011 (3)
C9	0.029 (4)	0.034 (4)	0.047 (5)	0.011 (3)	0.008 (4)	−0.002 (3)
C10	0.035 (4)	0.022 (4)	0.041 (4)	−0.002 (3)	0.015 (4)	−0.009 (3)
C11	0.025 (4)	0.036 (4)	0.035 (4)	−0.008 (3)	0.006 (3)	−0.016 (3)
C12	0.034 (4)	0.054 (5)	0.020 (4)	0.012 (4)	0.006 (3)	−0.011 (3)
Cl1	0.0320 (10)	0.0469 (12)	0.0410 (10)	−0.0091 (9)	0.0072 (8)	−0.0002 (9)
Cl2	0.0374 (12)	0.0488 (13)	0.0356 (10)	0.0041 (9)	−0.0081 (9)	0.0021 (8)
Fe1	0.0202 (5)	0.0199 (6)	0.0227 (5)	−0.0013 (4)	0.0026 (4)	−0.0025 (4)

Geometric parameters (Å, º) top

C1—C2	1.321 (9)	C7—Fe1	2.038 (7)
C1—Cl1	1.725 (7)	C7—H7	1
C1—Cl2	1.723 (7)	C8—C12	1.393 (10)
C2—C3	1.446 (9)	C8—C9	1.410 (10)
C2—H2	0.95	C8—Fe1	2.040 (7)
C3—C4	1.427 (9)	C8—H8	1
C3—C7	1.438 (10)	C9—C10	1.412 (10)
C3—Fe1	2.048 (6)	C9—Fe1	2.033 (7)
C4—C5	1.416 (10)	C9—H9	1
C4—Fe1	2.038 (6)	C10—C11	1.412 (10)
C4—H4	1	C10—Fe1	2.044 (6)
C5—C6	1.415 (10)	C10—H10	1
C5—Fe1	2.045 (7)	C11—C12	1.465 (10)
C5—H5	1	C11—Fe1	2.030 (7)
C6—C7	1.407 (9)	C11—H11	1
C6—Fe1	2.054 (7)	C12—Fe1	2.054 (6)
C6—H6	1	C12—H12	1

C2—C1—Cl1	125.0 (6)	C12—C11—Fe1	69.8 (4)
C2—C1—Cl2	122.1 (6)	C10—C11—H11	126.3
Cl1—C1—Cl2	112.9 (4)	C12—C11—H11	126.3
C1—C2—C3	130.7 (7)	Fe1—C11—H11	126.3
C1—C2—H2	114.6	C8—C12—C11	106.5 (7)
C3—C2—H2	114.6	C8—C12—Fe1	69.6 (4)
C4—C3—C2	131.5 (7)	C11—C12—Fe1	68.1 (4)
C4—C3—C7	106.8 (6)	C8—C12—H12	126.8
C2—C3—C7	121.7 (6)	C11—C12—H12	126.7
C4—C3—Fe1	69.2 (4)	Fe1—C12—H12	126.7
C2—C3—Fe1	126.2 (5)	C11—Fe1—C9	68.6 (3)
C7—C3—Fe1	69.0 (4)	C11—Fe1—C4	162.8 (3)
C5—C4—C3	108.1 (6)	C9—Fe1—C4	120.2 (3)
C5—C4—Fe1	70.0 (4)	C11—Fe1—C10	40.6 (3)
C3—C4—Fe1	69.9 (4)	C9—Fe1—C10	40.5 (3)
C5—C4—H4	125.9	C4—Fe1—C10	155.2 (3)
C3—C4—H4	126	C11—Fe1—C7	119.6 (3)
Fe1—C4—H4	126	C9—Fe1—C7	126.3 (3)
C6—C5—C4	108.5 (6)	C4—Fe1—C7	68.8 (3)
C6—C5—Fe1	70.1 (4)	C10—Fe1—C7	108.1 (3)
C4—C5—Fe1	69.4 (4)	C11—Fe1—C8	68.5 (3)
C6—C5—H5	125.7	C9—Fe1—C8	40.5 (3)
C4—C5—H5	125.7	C4—Fe1—C8	107.7 (3)
Fe1—C5—H5	125.7	C10—Fe1—C8	67.9 (3)
C5—C6—C7	108.1 (6)	C7—Fe1—C8	163.6 (3)
C5—C6—Fe1	69.5 (4)	C11—Fe1—C12	42.0 (3)
C7—C6—Fe1	69.3 (4)	C9—Fe1—C12	68.3 (3)
C5—C6—H6	126	C4—Fe1—C12	124.4 (3)
C7—C6—H6	126	C10—Fe1—C12	68.9 (3)
Fe1—C6—H6	126	C7—Fe1—C12	155.4 (3)
C6—C7—C3	108.5 (6)	C8—Fe1—C12	39.8 (3)
C6—C7—Fe1	70.5 (4)	C11—Fe1—C5	125.7 (3)
C3—C7—Fe1	69.8 (4)	C9—Fe1—C5	155.0 (3)
C6—C7—H7	125.8	C4—Fe1—C5	40.6 (3)
C3—C7—H7	125.8	C10—Fe1—C5	163.0 (3)
Fe1—C7—H7	125.8	C7—Fe1—C5	68.0 (3)
C12—C8—C9	109.8 (7)	C8—Fe1—C5	120.4 (3)
C12—C8—Fe1	70.6 (4)	C12—Fe1—C5	107.3 (3)
C9—C8—Fe1	69.5 (4)	C11—Fe1—C3	154.8 (3)
C12—C8—H8	125.1	C9—Fe1—C3	107.6 (3)
C9—C8—H8	125.1	C4—Fe1—C3	40.9 (3)
Fe1—C8—H8	125.1	C10—Fe1—C3	120.4 (3)
C8—C9—C10	108.0 (7)	C7—Fe1—C3	41.2 (3)
C8—C9—Fe1	70.0 (4)	C8—Fe1—C3	125.8 (3)
C10—C9—Fe1	70.2 (4)	C12—Fe1—C3	161.7 (3)
C8—C9—H9	126	C5—Fe1—C3	68.4 (3)
C10—C9—H9	126	C11—Fe1—C6	107.6 (3)
Fe1—C9—H9	126	C9—Fe1—C6	163.2 (3)
C9—C10—C11	108.3 (7)	C4—Fe1—C6	68.3 (3)
C9—C10—Fe1	69.3 (4)	C10—Fe1—C6	126.1 (3)
C11—C10—Fe1	69.2 (4)	C7—Fe1—C6	40.2 (3)
C9—C10—H10	125.8	C8—Fe1—C6	154.9 (3)
C11—C10—H10	125.8	C12—Fe1—C6	120.5 (3)
Fe1—C10—H10	125.8	C5—Fe1—C6	40.4 (3)
C10—C11—C12	107.4 (6)	C3—Fe1—C6	68.5 (3)
C10—C11—Fe1	70.2 (4)

Experimental details

Crystal data
Chemical formula	[Fe(C₅H₅)(C₇H₅Cl₂)]
M_r	280.95
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	14.340 (3), 7.4370 (15), 10.932 (2)
β (°)	108.48 (3)
V (Å³)	1105.8 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	1.81
Crystal size (mm)	0.3 × 0.2 × 0.2

Data collection
Diffractometer	Bruker APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1999)
T_min, T_max	0.594, 0.694
No. of measured, independent and observed [I > 2σ(I)] reflections	3293, 1908, 1372
R_int	0.05
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.063, 0.174, 1.02
No. of reflections	1908
No. of parameters	136
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.04, −0.46

Computer programs: SMART (Bruker, 2001), SAINT-Plus (Bruker, 1999), SHELXS90 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Acknowledgements

We are grateful to the French Ministere de la Recherche et Technologie for a PhD grant for SC. We also thank the Deutsche Forschungsgemeinschaft and the Fonds der Chemischen Industrie for financial support and the award of a scholarship (VHG).

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