1,1′-Di­bromo­ferrocene

The structure of 1,1′-di­bromo­ferrocene, [Fe(C₅H₄Br)₂], has been determined by single-crystal X-ray diffraction at 100 K. The two Br substituents are eclipsed in the solid state, with a Br...Br distance of 3.6172 (6) Å.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.037
• wR factor = 0.094
• Data-to-parameter ratio = 24.3

checkCIF/PLATON results

No syntax errors found



Alert level A
ABSTM02_ALERT_3_A  Crystal and compound unsuitable for non-numerical
               corrections. Product of mu and tmid > 3.0
             Value of mu given =     9.746 tmid =     0.360
PLAT065_ALERT_3_A Crystal Requires Numerical Correction mu*tmid ..       3.51

Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT431_ALERT_2_C Short Inter HL..A Contact  Br1    ..  Br2     ..       3.59 Ang.

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           30.50
           From the CIF: _reflns_number_total               2890
           Count of symmetry unique reflns         1554
           Completeness (_total/calc)            185.97%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1336
           Fraction of Friedel pairs measured     0.860
           Are heavy atom types Z>Si present          yes

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   2 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 1997–2002); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXTL (Bruker, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

1,1'-Dibromoferrocene

Crystal data

[Fe(C5H4Br)2]	F(000) = 328
Mr = 343.83	Dx = 2.357 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 6.2289 (6) Å	Cell parameters from 5466 reflections
b = 10.024 (1) Å	θ = 2.6–31.9°
c = 7.8351 (8) Å	µ = 9.75 mm^−1
β = 97.987 (2)°	T = 100 K
V = 484.49 (8) Å^3	Irregular, brown
Z = 2	0.50 × 0.36 × 0.31 mm

Data collection

Bruker AXS SMART APEX CCD diffractometer	2890 independent reflections
Radiation source: fine-focus sealed tube	2850 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
φ and ω scans	θmax = 30.5°, θmin = 2.6°
Absorption correction: multi-scan (SADABS in SAINT-Plus; Bruker, 2003)	h = −8→8
Tmin = 0.021, Tmax = 0.05	k = −14→14
5736 measured reflections	l = −11→10

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.037	H-atom parameters constrained
wR(F^2) = 0.095	w = 1/[σ^2(Fo^2) + (0.0733P)^2 + 0.3107P] where P = (Fo^2 + 2Fc^2)/3
S = 1.05	(Δ/σ)max = 0.001
2890 reflections	Δρmax = 1.12 e Å^−3
119 parameters	Δρmin = −0.66 e Å^−3
1 restraint	Absolute structure: Flack (1983), 1339 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.116 (13)

Special details

Experimental. The product of the linear absorption coefficient and the median crystal dimension for the crystal investigated here is 3.51, and an analytical absorption correction was thus advisable. However, the crystals under investigation had been of irregular shape and had to be cut to size, making face indexing impossible. The absorption correction used here was multi-scan, based on the program SADABS as implemented in the SAINT-Plus (Bruker, 2003). The experimental values for T_min and T_max after scaling are 0.021 and 0.050, respectively, and do not differ significantly from the expected values (0.021 and 0.049).

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 (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.00953 (7)	0.61869 (4)	1.02185 (5)	0.01565 (10)
Br2	0.12003 (6)	0.38079 (4)	0.69804 (6)	0.01804 (11)
C1	0.1934 (7)	0.7361 (4)	0.9230 (5)	0.0136 (7)
C2	0.1292 (7)	0.8295 (4)	0.7888 (6)	0.0146 (7)
H2	−0.0128	0.8415	0.7288	0.018*
C3	0.3196 (8)	0.9018 (4)	0.7615 (6)	0.0187 (8)
H3	0.3262	0.9710	0.6796	0.022*
C4	0.4979 (7)	0.8521 (4)	0.8785 (6)	0.0183 (8)
H4	0.6434	0.8827	0.8875	0.022*
C5	0.4210 (7)	0.7484 (4)	0.9798 (5)	0.0151 (7)
H5	0.5046	0.6978	1.0676	0.018*
C6	0.3011 (6)	0.5130 (4)	0.6298 (5)	0.0128 (7)
C7	0.5271 (6)	0.5286 (4)	0.6923 (5)	0.0140 (7)
H7	0.6090	0.4787	0.7818	0.017*
C8	0.6049 (7)	0.6328 (4)	0.5947 (5)	0.0182 (8)
H8	0.7502	0.6640	0.6067	0.022*
C9	0.4290 (8)	0.6830 (5)	0.4755 (5)	0.0198 (8)
H9	0.4368	0.7541	0.3964	0.024*
C10	0.2400 (7)	0.6080 (4)	0.4960 (5)	0.0156 (7)
H10	0.0997	0.6190	0.4326	0.019*
Fe1	0.36191 (8)	0.70162 (5)	0.72275 (6)	0.00994 (12)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.01640 (17)	0.01861 (18)	0.01314 (18)	−0.00105 (13)	0.00630 (12)	0.00039 (14)
Br2	0.01915 (18)	0.01436 (18)	0.0212 (2)	−0.00441 (14)	0.00490 (14)	−0.00214 (14)
C1	0.0163 (16)	0.0139 (16)	0.0115 (15)	0.0000 (13)	0.0055 (13)	−0.0015 (12)
C2	0.0171 (17)	0.0126 (16)	0.0153 (17)	0.0036 (13)	0.0066 (14)	−0.0003 (13)
C3	0.027 (2)	0.0119 (18)	0.0189 (18)	−0.0037 (14)	0.0095 (16)	−0.0026 (13)
C4	0.0203 (17)	0.0182 (19)	0.0178 (18)	−0.0067 (14)	0.0078 (15)	−0.0077 (14)
C5	0.0168 (17)	0.0181 (17)	0.0105 (15)	−0.0019 (13)	0.0016 (13)	−0.0054 (13)
C6	0.0153 (16)	0.0110 (16)	0.0117 (16)	−0.0021 (13)	0.0007 (13)	−0.0028 (12)
C7	0.0131 (16)	0.0148 (16)	0.0142 (16)	0.0007 (13)	0.0029 (13)	−0.0051 (13)
C8	0.0193 (17)	0.019 (2)	0.0182 (17)	−0.0029 (15)	0.0112 (14)	−0.0056 (15)
C9	0.031 (2)	0.0178 (19)	0.0129 (17)	−0.0001 (17)	0.0108 (16)	0.0002 (14)
C10	0.0221 (17)	0.0144 (16)	0.0101 (14)	0.0016 (15)	0.0010 (13)	−0.0028 (13)
Fe1	0.0129 (2)	0.0091 (2)	0.0084 (2)	−0.00081 (17)	0.00358 (17)	−0.00135 (17)

Geometric parameters (Å, º)

Br1—C1	1.882 (4)	C5—H5	0.9500
Br2—C6	1.866 (4)	C6—C10	1.428 (5)
C1—C2	1.423 (6)	C6—C7	1.433 (5)
C1—C5	1.431 (6)	C6—Fe1	2.042 (4)
C1—Fe1	2.035 (4)	C7—C8	1.419 (6)
C2—C3	1.431 (6)	C7—Fe1	2.048 (4)
C2—Fe1	2.054 (4)	C7—H7	0.9500
C2—H2	0.9500	C8—C9	1.429 (7)
C3—C4	1.428 (7)	C8—Fe1	2.048 (4)
C3—Fe1	2.052 (4)	C8—H8	0.9500
C3—H3	0.9500	C9—C10	1.425 (6)
C4—C5	1.430 (6)	C9—Fe1	2.046 (4)
C4—Fe1	2.048 (4)	C9—H9	0.9500
C4—H4	0.9500	C10—Fe1	2.059 (4)
C5—Fe1	2.051 (4)	C10—H10	0.9500
C2—C1—C5	109.7 (4)	Fe1—C9—H9	125.8
C2—C1—Br1	126.2 (3)	C9—C10—C6	107.1 (4)
C5—C1—Br1	124.0 (3)	C9—C10—Fe1	69.2 (2)
C2—C1—Fe1	70.4 (2)	C6—C10—Fe1	69.0 (2)
C5—C1—Fe1	70.1 (2)	C9—C10—H10	126.4
Br1—C1—Fe1	128.3 (2)	C6—C10—H10	126.4
C1—C2—C3	106.9 (4)	Fe1—C10—H10	126.9
C1—C2—Fe1	68.9 (2)	C1—Fe1—C6	110.01 (17)
C3—C2—Fe1	69.5 (2)	C1—Fe1—C9	160.16 (18)
C1—C2—H2	126.6	C6—Fe1—C9	68.31 (17)
C3—C2—H2	126.6	C1—Fe1—C7	123.71 (16)
Fe1—C2—H2	126.6	C6—Fe1—C7	41.03 (15)
C4—C3—C2	108.3 (4)	C9—Fe1—C7	68.93 (17)
C4—C3—Fe1	69.5 (2)	C1—Fe1—C4	68.31 (17)
C2—C3—Fe1	69.7 (2)	C6—Fe1—C4	159.23 (18)
C4—C3—H3	125.8	C9—Fe1—C4	120.60 (18)
C2—C3—H3	125.8	C7—Fe1—C4	121.35 (17)
Fe1—C3—H3	126.6	C1—Fe1—C8	158.47 (18)
C3—C4—C5	108.6 (4)	C6—Fe1—C8	68.07 (16)
C3—C4—Fe1	69.8 (2)	C9—Fe1—C8	40.85 (18)
C5—C4—Fe1	69.7 (2)	C7—Fe1—C8	40.53 (16)
C3—C4—H4	125.7	C4—Fe1—C8	105.51 (18)
C5—C4—H4	125.7	C1—Fe1—C5	41.00 (16)
Fe1—C4—H4	126.4	C6—Fe1—C5	124.14 (16)
C4—C5—C1	106.5 (4)	C9—Fe1—C5	156.65 (19)
C4—C5—Fe1	69.5 (2)	C7—Fe1—C5	106.49 (17)
C1—C5—Fe1	68.9 (2)	C4—Fe1—C5	40.83 (17)
C4—C5—H5	126.7	C8—Fe1—C5	120.94 (18)
C1—C5—H5	126.7	C1—Fe1—C3	68.24 (17)
Fe1—C5—H5	126.4	C6—Fe1—C3	159.50 (18)
C10—C6—C7	109.1 (4)	C9—Fe1—C3	106.05 (18)
C10—C6—Br2	125.0 (3)	C7—Fe1—C3	157.31 (18)
C7—C6—Br2	125.7 (3)	C4—Fe1—C3	40.77 (19)
C10—C6—Fe1	70.3 (2)	C8—Fe1—C3	121.39 (17)
C7—C6—Fe1	69.7 (2)	C5—Fe1—C3	68.90 (18)
Br2—C6—Fe1	130.2 (2)	C1—Fe1—C2	40.74 (16)
C8—C7—C6	106.8 (4)	C6—Fe1—C2	124.40 (16)
C8—C7—Fe1	69.8 (2)	C9—Fe1—C2	122.64 (18)
C6—C7—Fe1	69.3 (2)	C7—Fe1—C2	160.31 (17)
C8—C7—H7	126.6	C4—Fe1—C2	68.80 (17)
C6—C7—H7	126.6	C8—Fe1—C2	158.26 (17)
Fe1—C7—H7	125.9	C5—Fe1—C2	69.30 (17)
C7—C8—C9	108.9 (4)	C3—Fe1—C2	40.79 (17)
C7—C8—Fe1	69.7 (2)	C1—Fe1—C10	125.10 (17)
C9—C8—Fe1	69.5 (2)	C6—Fe1—C10	40.74 (16)
C7—C8—H8	125.6	C9—Fe1—C10	40.63 (18)
C9—C8—H8	125.6	C7—Fe1—C10	69.16 (16)
Fe1—C8—H8	126.8	C4—Fe1—C10	157.27 (18)
C10—C9—C8	108.1 (4)	C8—Fe1—C10	68.45 (17)
C10—C9—Fe1	70.2 (2)	C5—Fe1—C10	161.10 (17)
C8—C9—Fe1	69.6 (2)	C3—Fe1—C10	122.28 (18)
C10—C9—H9	126.0	C2—Fe1—C10	108.26 (17)
C8—C9—H9	126.0