Ferrocenylbutadiyne

The title compound, [Fe(C₅H₅)(C₉H₅)], crystallizes in a form of a π–π-stacked assembly formed as a result of strong inter­molecular π–π inter­actions between (a) the triple bonds of two neighboring butadiyne substituents overlapping in a `head-to-tail' fashion [characterized by C...C short contacts of 3.622 (5), 3.567 (6) and 3.556 (6) Å] and (b) the triple bonds of the butadiyne substituent and substituted cyclo­pendadiene ring of neighboring mol­ecules [C...C = 3.474 (5) and 3.492 (6) Å]. The linear butadiyne substituent has alternating C—C triple and single bonds, while the unsubstituted cyclo­penta­diene ring is slightly positionally disordered (although the structure reported here was solved as non-disordered) and retains a close to eclipsed conformation.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.007 Å
• R factor = 0.048
• wR factor = 0.136
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

No syntax errors found



Datablock: I


Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C13    --  C14     ..       9.64 su
PLAT241_ALERT_2_B Check High      Ueq as Compared to Neighbors for         C9
PLAT242_ALERT_2_B Check Low       Ueq as Compared to Neighbors for        Fe1
PLAT411_ALERT_2_B Short Inter H...H Contact  H6     ..  H15     ..       1.88 Ang.

Alert level C
            Value of measurement temperature given =   298.000
            Value of melting point given =     0.000
PLAT220_ALERT_2_C Large Non-Solvent    C     Ueq(max)/Ueq(min) ...       2.56 Ratio
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C12    --  C13     ..       5.04 su
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         C8
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.15
PLAT341_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          7
PLAT350_ALERT_3_C Short   C-H Bond (0.96A)   C14    -   H15    ...       0.82 Ang.
PLAT372_ALERT_2_C Short  C(sp)-C(sp)   Bond  C13    -   C14    ...       1.11 Ang.
PLAT373_ALERT_2_C Long   C(sp)-C(sp)   Bond  C12    -   C13    ...       1.38 Ang.
PLAT234_ALERT_4_C Large Hirshfeld Difference C9     --  C10     ..       0.16  Ang.

   0 ALERT level A = In general: serious problem
   4 ALERT level B = Potentially serious problem
   9 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
  10 ALERT type 2 Indicator that the structure model may be wrong or deficient
   2 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Ferrocene derivatives have been useful as antitumor agents (Fouda et al., 2007) and as electron transfer molecules. (Stepnika, 2008; Nemykin et al., 2001, 2007a, 2007b, 2007c, 2008; Osakada et al., 2006) The title compound represents a precursor for the preparation of butadiyne like dinuclear ferrocene molecules. (Bruce et al., 2004, Yuan et al., 1993).

There are a number of known structures of substituted ferrocenes (Stepnika, 2008, Nemykin et al., 2007a, 2007c) but this is the first reported crystal structure of a butadiyne substituted ferrocene.

The molecule crystallizes as a π-π stacked assembly in the centrosymmetric monoclinic space group P2₁/c . π-π stacked assembly formed as a result of strong intermolecular π-π interactions between (a) the triple bonds of two butadiyne substituents in molecules 'B' and 'C' (Figure 2) overlapping in 'head-to-tail' fashion and (b) the triple bonds of butadiyne substituents of a substituted cyclopendadiene ring along crystallographic b axis (Figure 2). Intermolecular π-π interactions between between the triple bonds of two butadiyne substituents (overlapping in 'head-to-tail' fashion) consists of three short contacts between C12 and C14 (3.622 (5) Å, -x, 1 - y, 1 - z), C13 and C14 (3.567 (6) Å, -x, 1 - y, 1 - z), and C13 and C13 (3.556 (6) Å, -x, 1 - y, 1 - z) carbon atoms of neighboring molecules. Intermolecular π-π interactions between between the triple bonds of butadiyne substituents and substituted cyclopentadiene ring of neighboring molecule can be characterized by two short contacts between C2 and C11 (3.474 (5) Å, -x, -y, 1 - z) and C3 and C12 (3.492 (6) Å, -x, -y, 1 - z) pairs of carbon atoms. The terminal H15 atom of the butadiyne substituent of one molecule is in close proximity to the H6 atom on the unsubstituted cyclopentadienyl ring of the other molecule. Although the unsubstituted cyclopentadiyne ring is, probably, disordered over two crystallographical positions (with disordered structure solution available from the authors on request), the unsubstituted cyclopentadiene ring retains close to eclipsed conformation of ferrocene subunit. In addition, the butadiyne substituent has alternating C—C triple and single bonds.

Related literature

For general synthesis and applications of substituted ferrocenes and related macrocycles, see: Fouda et al. (2007); Nemykin et al. (2001, 2007a, 2007b, 2008); Stepnika (2008); Osakada et al. (2006). For the synthesis of the title compound, see: Yuan et al. (1993); Nemykin et al. (2007c). For examples of the use of the title compound, see Bruce et al. (2004).

S2. Experimental

The title compound was obtained as by-product of the iodination reaction of ferrocenylacetylene (Nemykin et al., 2007c). Melting point (81 ^oC, dec.). ¹H NMR (CDCl₃, tms, p.p.m.): 4.29, 5H, Cp; 4.63, 2H, α-Cp; 4.39, 2H, β-Cp; 2.39, 1H, butadiyne C—H. ¹³C (CDCl₃, tms, p.p.m.): 71.0, Cp; 60.1, α-Cp; 70.6, β-Cp; 73.5, i-Cp; 66.9, ≡C—H; 70.4, C≡C—H; 71.2, Cp—C≡C-; 81.6, Cp-C≡C–). NMR spectra are similar to those reported earlier (Yuan et al.,1993).

S3. Refinement

All cyclopentadienyl H atoms positioned geometrically, while the terminal butadiyne H atom was located on a Fourier map. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C(Ferrocene) - H 0.93; ≡C—H 0.82 Å) and U_iso(H) (in the range 1.2–1.5 times U_eq of the parent atom) using default procedure available in Crystals for Windows software (Betteridge et al., 2003). After this the positions were refined with riding constraints.

The difference between the number of independent reflections (2411) and those included in the refinement (2402) is originate from the filter used by Crystals for Windows software. The filter uses (sin theta/lambda)² at least 0.0100 cutoff in order to eliminate reflections that may be poorly measured in the vicinity of the beam stop.

Computing details

Data collection: AFC-7R Diffractometer Control Software (Rigaku/MSC, 1997); cell refinement: WinAFC (Rigaku/MSC, 2000); data reduction: TEXSAN (Rigaku/MSC, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).

Figures

	Fig. 1. The title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are shown as spheres of arbitary radius.
	Fig. 2. Intermolecular π-π interactions in the title compound. displacement ellipsoids drawn at the 50% probability level. Molecules located at: 1 - x, 3/2 + y, 3/2 - z (molecule A); 1 + x, 3/2 - y, 1/2 + z (molecule B); 1 - x, 1/2 + y, 3/2 - z (molecule C); and 1 + x, 1/2 - y, 1/2 + z (molecule D).

Ferrocenylbutadiyne

Crystal data

[Fe(C5H5)(C9H5)]	F(000) = 480
Mr = 234.08	Dx = 1.487 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 7.9438 (16) Å	θ = 15–18°
b = 10.332 (2) Å	µ = 1.40 mm^−1
c = 12.835 (3) Å	T = 298 K
β = 97.01 (3)°	Block, brown
V = 1045.5 (4) Å^3	0.45 × 0.30 × 0.25 mm
Z = 4

Data collection

Rigaku AFC-7R diffractometer	Rint = 0.052
Graphite monochromator	θmax = 27.5°, θmin = 2.5°
ω/2θ scans	h = −10→10
Absorption correction: ψ scan (North et al., 1968)	k = −13→0
Tmin = 0.58, Tmax = 0.70	l = 0→16
2549 measured reflections	3 standard reflections every 150 reflections
2411 independent reflections	intensity decay: 0.0%
2248 reflections with I > 2σ(I)

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.048	H-atom parameters constrained
wR(F^2) = 0.136	Method = Modified Sheldrick w = 1/[σ^2(F^2) + (0.07P)^2 + 0.99P], where P = [max(Fo^2,0) + 2Fc^2]/3
S = 1.08	(Δ/σ)max = 0.000284
2402 reflections	Δρmax = 0.52 e Å^−3
136 parameters	Δρmin = −0.47 e Å^−3
0 restraints

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Fe1	0.29866 (5)	0.10003 (4)	0.31022 (3)	0.0488
C1	0.1074 (4)	0.0794 (3)	0.4007 (3)	0.0518
C2	0.2591 (4)	0.0175 (3)	0.4488 (3)	0.0575
C3	0.3047 (5)	−0.0793 (3)	0.3799 (3)	0.0668
C4	0.1850 (6)	−0.0782 (3)	0.2897 (3)	0.0710
C5	0.0628 (4)	0.0191 (4)	0.3004 (3)	0.0622
C6	0.3496 (7)	0.2904 (4)	0.2979 (5)	0.0866
C7	0.4938 (7)	0.2257 (5)	0.3366 (4)	0.0928
C8	0.5285 (7)	0.1368 (5)	0.2642 (8)	0.1210
C9	0.4034 (14)	0.1459 (8)	0.1794 (5)	0.1336
C10	0.2955 (7)	0.2426 (7)	0.2031 (5)	0.1036
C11	0.0220 (4)	0.1842 (3)	0.4417 (3)	0.0543
C12	−0.0531 (4)	0.2707 (4)	0.4767 (3)	0.0594
C13	−0.1411 (5)	0.3705 (4)	0.5177 (3)	0.0665
C14	−0.2128 (5)	0.4495 (4)	0.5504 (4)	0.0755
H2	0.3169	0.0377	0.5142	0.0693*
H3	0.3970	−0.1349	0.3926	0.0865*
H4	0.1871	−0.1323	0.2320	0.0850*
H5	−0.0298	0.0394	0.2515	0.0744*
H6	0.2992	0.3561	0.3327	0.1061*
H7	0.5582	0.2387	0.4013	0.1128*
H8	0.6195	0.0796	0.2682	0.1788*
H9	0.3901	0.0972	0.1180	0.1600*
H10	0.2000	0.2722	0.1607	0.1248*
H15	−0.2661	0.5084	0.5739	0.0916*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Fe1	0.0479 (3)	0.0438 (3)	0.0572 (3)	−0.00690 (17)	0.01690 (19)	−0.00211 (17)
C1	0.0481 (15)	0.0538 (16)	0.0560 (16)	−0.0080 (13)	0.0158 (13)	−0.0011 (13)
C2	0.0606 (18)	0.0546 (17)	0.0591 (17)	−0.0015 (15)	0.0146 (14)	0.0087 (14)
C3	0.070 (2)	0.0454 (17)	0.090 (3)	0.0012 (15)	0.029 (2)	0.0067 (17)
C4	0.084 (3)	0.0535 (18)	0.083 (3)	−0.0227 (18)	0.038 (2)	−0.0177 (17)
C5	0.0541 (17)	0.069 (2)	0.0638 (18)	−0.0216 (16)	0.0107 (14)	−0.0091 (16)
C6	0.099 (3)	0.0441 (18)	0.128 (4)	−0.008 (2)	0.060 (3)	0.005 (2)
C7	0.082 (3)	0.099 (4)	0.093 (3)	−0.051 (3)	−0.003 (2)	0.017 (3)
C8	0.085 (4)	0.068 (3)	0.229 (8)	0.006 (3)	0.096 (5)	0.031 (4)
C9	0.206 (8)	0.120 (5)	0.093 (4)	−0.098 (5)	0.095 (5)	−0.043 (4)
C10	0.079 (3)	0.125 (4)	0.103 (4)	−0.035 (3)	−0.005 (3)	0.061 (4)
C11	0.0476 (16)	0.0597 (18)	0.0577 (17)	−0.0082 (14)	0.0149 (13)	0.0007 (14)
C12	0.0527 (17)	0.064 (2)	0.0631 (19)	−0.0020 (15)	0.0138 (14)	−0.0029 (15)
C13	0.058 (2)	0.073 (2)	0.070 (2)	−0.0079 (18)	0.0147 (17)	−0.0011 (18)
C14	0.073 (2)	0.066 (2)	0.091 (3)	0.0128 (19)	0.028 (2)	−0.018 (2)

Geometric parameters (Å, º)

Fe1—C1	2.032 (3)	C4—C5	1.416 (6)
Fe1—C2	2.031 (3)	C4—H4	0.930
Fe1—C3	2.056 (3)	C5—H5	0.930
Fe1—C4	2.054 (3)	C6—C7	1.366 (7)
Fe1—C5	2.042 (3)	C6—C10	1.335 (8)
Fe1—C6	2.018 (4)	C6—H6	0.930
Fe1—C7	2.019 (4)	C7—C8	1.359 (8)
Fe1—C8	2.023 (4)	C7—H7	0.930
Fe1—C9	2.019 (4)	C8—C9	1.384 (10)
Fe1—C10	2.013 (4)	C8—H8	0.930
C1—C2	1.436 (5)	C9—C10	1.375 (10)
C1—C5	1.435 (5)	C9—H9	0.930
C1—C11	1.413 (5)	C10—H10	0.930
C2—C3	1.412 (5)	C11—C12	1.192 (5)
C2—H2	0.930	C12—C13	1.385 (5)
C3—C4	1.406 (6)	C13—C14	1.107 (5)
C3—H3	0.930	C14—H15	0.820
C1—Fe1—C2	41.37 (14)	Fe1—C2—H2	125.7
C1—Fe1—C3	68.68 (14)	C3—C2—H2	126.0
C2—Fe1—C3	40.40 (15)	C2—C3—Fe1	68.87 (19)
C1—Fe1—C4	68.39 (14)	C2—C3—C4	108.1 (3)
C2—Fe1—C4	67.87 (16)	Fe1—C3—C4	69.9 (2)
C3—Fe1—C4	40.00 (18)	C2—C3—H3	125.8
C1—Fe1—C5	41.25 (13)	Fe1—C3—H3	127.5
C2—Fe1—C5	69.11 (15)	C4—C3—H3	126.1
C3—Fe1—C5	68.30 (16)	C3—C4—Fe1	70.1 (2)
C4—Fe1—C5	40.45 (16)	C3—C4—C5	109.2 (3)
C1—Fe1—C6	108.53 (16)	Fe1—C4—C5	69.31 (19)
C2—Fe1—C6	122.10 (19)	C3—C4—H4	125.2
C3—Fe1—C6	156.7 (2)	Fe1—C4—H4	126.1
C4—Fe1—C6	162.4 (2)	C5—C4—H4	125.6
C5—Fe1—C6	125.9 (2)	C1—C5—C4	107.3 (3)
C1—Fe1—C7	125.7 (2)	C1—C5—Fe1	69.02 (17)
C2—Fe1—C7	108.70 (18)	C4—C5—Fe1	70.2 (2)
C3—Fe1—C7	122.0 (2)	C1—C5—H5	126.5
C4—Fe1—C7	156.2 (2)	C4—C5—H5	126.1
C5—Fe1—C7	162.5 (2)	Fe1—C5—H5	126.4
C1—Fe1—C8	162.0 (3)	Fe1—C6—C7	70.2 (2)
C2—Fe1—C8	125.2 (3)	Fe1—C6—C10	70.4 (3)
C3—Fe1—C8	108.8 (2)	C7—C6—C10	108.2 (5)
C4—Fe1—C8	122.0 (2)	Fe1—C6—H6	124.8
C5—Fe1—C8	156.0 (3)	C7—C6—H6	125.0
C1—Fe1—C9	155.8 (4)	C10—C6—H6	126.7
C2—Fe1—C9	161.8 (4)	C6—C7—Fe1	70.2 (2)
C3—Fe1—C9	125.7 (3)	C6—C7—C8	108.3 (5)
C4—Fe1—C9	108.88 (19)	Fe1—C7—C8	70.5 (3)
C5—Fe1—C9	120.9 (3)	C6—C7—H7	126.8
C1—Fe1—C10	121.2 (2)	Fe1—C7—H7	124.8
C2—Fe1—C10	156.2 (3)	C8—C7—H7	124.9
C3—Fe1—C10	162.7 (3)	Fe1—C8—C7	70.2 (3)
C4—Fe1—C10	126.9 (2)	Fe1—C8—C9	69.8 (3)
C5—Fe1—C10	108.81 (18)	C7—C8—C9	107.8 (5)
C6—Fe1—C7	39.6 (2)	Fe1—C8—H8	126.0
C6—Fe1—C8	66.3 (2)	C7—C8—H8	127.8
C7—Fe1—C8	39.3 (3)	C9—C8—H8	124.4
C6—Fe1—C9	66.4 (2)	C8—C9—Fe1	70.1 (3)
C7—Fe1—C9	66.6 (2)	C8—C9—C10	106.5 (5)
C8—Fe1—C9	40.0 (3)	Fe1—C9—C10	69.8 (3)
C6—Fe1—C10	38.7 (2)	C8—C9—H9	128.7
C7—Fe1—C10	65.8 (2)	Fe1—C9—H9	124.2
C8—Fe1—C10	66.4 (2)	C10—C9—H9	124.8
C9—Fe1—C10	39.9 (3)	C9—C10—Fe1	70.3 (3)
Fe1—C1—C2	69.28 (18)	C9—C10—C6	109.3 (5)
Fe1—C1—C5	69.73 (18)	Fe1—C10—C6	70.9 (3)
C2—C1—C5	107.2 (3)	C9—C10—H10	126.6
Fe1—C1—C11	124.0 (2)	Fe1—C10—H10	125.6
C2—C1—C11	126.6 (3)	C6—C10—H10	124.1
C5—C1—C11	126.1 (3)	C1—C11—C12	178.5 (3)
C1—C2—Fe1	69.34 (18)	C11—C12—C13	179.5 (4)
C1—C2—C3	108.2 (3)	C12—C13—C14	179.3 (5)
Fe1—C2—C3	70.7 (2)	C13—C14—H15	179.3
C1—C2—H2	125.8