([eta]⁶-2-Bromo-1,1'-biphenyl)tricarbonylchromium

The title compound, [Cr(C₁₂H₉Br)(CO)₃], crystallizes in the triclinic space group with close Br...Br separations. These contacts, along with several other factors, influence the (Ph)C-C(o-BrC₆H₄) dihedral angle of 58.82 (6)°. The typical piano-stool coordination about the Cr atom is in excellent agreement with the results of density functional theory calculations.

S1. Comment

In the course of synthesizing functionalized biphenyl chromium tricarbonyl complexes, we became interested in (η⁶-2-bromo-1,1'-biphenyl)chromium tricarbonyl, (I), since the possibility of metal-halogen exchange at the 2-position of the molecule suggests its potential use as an intermediate in synthetic and mechanistic studies. Compound (I) has been previously described as being unexpectedly unreactive toward metal-halogen exchange when treated with n-butyl lithium, apparently due to steric interactions (Oprunenko et al., 1991; Oprunenko, 2000). In an effort to explore some of the steric interactions in the molecule, we studied the low-temperature ¹H NMR spectra of (I), but saw no decoalescence of peaks at temperatures as low as 183 K, placing an upper boundary of 9 kcal mol⁻¹ (1 kcal mol⁻¹ = 4.184 kJ mol⁻¹) on the rotational barrier about the (Ph)C—C(o-BrC₆H₄) bond of the biphenyl ligand. This relatively low barrier, similar to PM3 Please define results of 9.06 kcal mol⁻¹ for the free ligand, suggests only a small amount of rotational steric hindrance in (I). Also, we have recently established that, while the compound is unreactive toward n-butyl lithium, the more reactive reagent tert-butyl lithium successfully brings about metal-halogen exchange in (I). This unexpected selectivity toward alkyl lithium reagents, uncertainties regarding steric interactions in the molecule, and the lack of any published mono-substituted biphenyl chromium tricarbonyl structures prompted us to explore the solid-state structure of (I), which is reported here. \sch

In the solid-state structure of (I), the Cr atom is in a typical piano-stool geometry, displaced by 1.7178 (11) Å from the plane of the phenyl ring. A Cambridge Structural Database (CSD, Version?; Allen, 2002) search on all the chromium tricarbonyl compounds with the Cr atom coordinating in an η⁶ fashion to a substituted phenyl ring returned 579 hits, from which the average Cr—C(Ph), Cr-centroid(Ph) and Cr—CO distances were 2.23 (4), 1.73 (2) and 1.83 (2) Å, respectively. Similar parameters for chromium tricarbonyl with a monosubstituted η⁶-coordinated phenyl ring are 2.22 (2), 1.716 (10) and 1.836 (12) Å, respectively, based on 77 hits in the CSD. These parameters are in excellent agreement with the data observed in the solid-state structure of (I), which are 2.225 (7), 1.7178 (11) and 1.849 (5) Å, respectively.

An interesting aspect of the structure of (I), also detected by the PLATON checking software (Spek, 2003), is the length of the C—C bonds within the coordinated phenyl ring. These average 1.415 (11) Å, a value noticeably exceeding the length of the idealized C—C bond with bond order 1.5. The corresponding C—C bond length in relevant compounds averaged 1.401 (16) Å, based on 242 entries in the CSD. During this CSD search it became obvious that, in a number of complexes, authors used the idealized C—C distance of 1.39 Å for their Cr-ligated phenyl rings; thus, we excluded those entries from the statistics cited above.

The dihedral angle between the planes of the phenyl rings in (I) is 58.82 (6)°, a value in excellent agreement with the angle of 59.1° in the structure of (I) optimized at the B3LYP/LANL2DZ level of theory (GAUSSIAN98; Frisch et al., 1998) and close to the 62.5° dihedral angle in free 2-bromobiphenyl optimized at the B3LYP/6–31+G* level. These angles are close to the corresponding torsion angles between the phenyl rings in 2-hydroxybiphenyl [57.0 (7)°; Perrin et al., 1987] and 2-fluorobiphenyl [54 (3)°; Rajnikant et al., 1995]. In the solid-state structure of (I), the torsion angle in question depends on the close Br···Br(2 − x, 1 − y, −z) contacts [3.5882 (6) Å] that fall within the sum of two Br van der Waals radii. Additionally, each Br atom is in the vicinity of a third Br atom. However, this Br···Br(3 − x, −y, −z) separation [4.2645 (6) Å] is outside the van der Walls contact sphere. These two contacts, the interaction between the ortho-H atom of the non-coordinated ring with the Cr(CO)₃ core, and the interaction between the Br atom and the ortho-H atom of the coordinated ring (Br···H6 3.09 Å) all play a role in determining the Ph—Ph torsion angle. However, it is impossible to quantify these contributions. If the observed conformation is predominant in solution, it appears that the Br atom of (I) would be easily accessible for Li—Br exchange, since it is known that metal-halogen exchange reactions require a 180° R—X—R geometry between an aryl halide R—X and an attacking alkyl lithium reagent R—Li (Beak & Allen, 1992).

S2. Experimental

The title compound was prepared according to the published procedure of Oprunenko (2000). Final crystals from what solvent?

S3. Refinement

Please provide brief details of H-atom refinement.

Computing details

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

Figures

	Fig. 1. The molecular structure of (I), with displacement ellipsoids at the 50% probability level. H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. A packing diagram of (I) viewed along the b axis. The dashed lines show close Br···Br contacts.

(η⁶-2-Bromo-1,1'-biphenyl)tricarbonylchromium

Crystal data

[Cr(C12H9Br)(CO)3]	Z = 2
Mr = 369.13	F(000) = 364
Triclinic, P1	Dx = 1.812 Mg m^−3
a = 7.3186 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.3934 (8) Å	Cell parameters from 949 reflections
c = 14.5131 (16) Å	θ = 2–25°
α = 79.330 (2)°	µ = 3.80 mm^−1
β = 78.867 (2)°	T = 100 K
γ = 62.067 (2)°	Block, colourless
V = 676.67 (13) Å^3	0.44 × 0.22 × 0.16 mm

Data collection

Make Model CCD area-detector diffractometer	3220 independent reflections
Radiation source: fine-focus sealed tube	2885 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.053
ϕ and ω scans	θmax = 28.4°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2000-2003)	h = −9→9
Tmin = 0.268, Tmax = 0.546	k = −9→9
7381 measured reflections	l = −19→19

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.034	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.099	H-atom parameters constrained
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0604P)^2 + 0.1534P] where P = (Fo^2 + 2Fc^2)/3
3220 reflections	(Δ/σ)max = 0.001
181 parameters	Δρmax = 0.71 e Å^−3
0 restraints	Δρmin = −0.49 e Å^−3

Special details

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
Cr	0.66788 (6)	0.28192 (6)	0.33284 (3)	0.01558 (12)
Br	1.18734 (4)	0.23542 (4)	0.019518 (18)	0.02284 (11)
O1	0.4996 (3)	0.0595 (3)	0.24723 (16)	0.0312 (5)
O2	0.7174 (4)	−0.0141 (4)	0.50922 (18)	0.0488 (7)
O3	0.2291 (3)	0.5392 (3)	0.41721 (15)	0.0327 (5)
C1	0.9519 (4)	0.1876 (4)	0.22605 (17)	0.0156 (4)
C2	1.0085 (4)	0.1847 (4)	0.31389 (18)	0.0187 (5)
H2	1.1164	0.0628	0.3401	0.022*
C3	0.9066 (4)	0.3614 (4)	0.36395 (18)	0.0208 (5)
H3	0.9469	0.3579	0.4229	0.025*
C4	0.7457 (4)	0.5413 (4)	0.3256 (2)	0.0231 (5)
H4	0.6768	0.6595	0.3590	0.028*
C5	0.6862 (4)	0.5472 (4)	0.23805 (18)	0.0202 (5)
H5	0.5779	0.6696	0.2124	0.024*
C6	0.7870 (4)	0.3718 (4)	0.18814 (17)	0.0175 (5)
H6	0.7455	0.3760	0.1294	0.021*
C7	1.0612 (4)	−0.0014 (4)	0.17527 (17)	0.0163 (5)
C8	1.1707 (4)	−0.0037 (4)	0.08503 (18)	0.0176 (5)
C9	1.2775 (4)	−0.1824 (4)	0.03916 (19)	0.0208 (5)
H9	1.3506	−0.1801	−0.0224	0.025*
C10	1.2744 (4)	−0.3638 (4)	0.0855 (2)	0.0236 (5)
H10	1.3457	−0.4864	0.0553	0.028*
C11	1.1683 (4)	−0.3668 (4)	0.1752 (2)	0.0237 (5)
H11	1.1678	−0.4915	0.2064	0.028*
C12	1.0626 (4)	−0.1880 (4)	0.21950 (19)	0.0203 (5)
H12	0.9897	−0.1918	0.2810	0.024*
C13	0.5635 (4)	0.1446 (4)	0.28071 (19)	0.0205 (5)
C14	0.6985 (4)	0.0994 (5)	0.4410 (2)	0.0295 (6)
C15	0.3981 (4)	0.4413 (4)	0.38505 (18)	0.0224 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cr	0.0133 (2)	0.0184 (2)	0.0152 (2)	−0.00802 (16)	−0.00070 (15)	−0.00091 (15)
Br	0.02299 (16)	0.02073 (15)	0.02436 (16)	−0.01178 (12)	0.00132 (11)	−0.00029 (10)
O1	0.0235 (10)	0.0279 (10)	0.0471 (13)	−0.0130 (8)	−0.0026 (9)	−0.0134 (9)
O2	0.0379 (13)	0.0743 (17)	0.0392 (13)	−0.0375 (13)	−0.0206 (11)	0.0336 (13)
O3	0.0214 (10)	0.0448 (12)	0.0274 (11)	−0.0103 (9)	0.0050 (8)	−0.0146 (9)
C1	0.0143 (10)	0.0174 (11)	0.0158 (11)	−0.0088 (9)	0.0016 (9)	−0.0022 (9)
C2	0.0151 (11)	0.0240 (12)	0.0184 (12)	−0.0108 (10)	−0.0013 (9)	−0.0004 (9)
C3	0.0201 (12)	0.0312 (13)	0.0176 (12)	−0.0169 (11)	0.0003 (9)	−0.0055 (10)
C4	0.0222 (13)	0.0220 (12)	0.0275 (13)	−0.0124 (10)	0.0044 (10)	−0.0091 (10)
C5	0.0194 (12)	0.0167 (11)	0.0233 (13)	−0.0092 (10)	0.0023 (10)	−0.0017 (9)
C6	0.0164 (11)	0.0182 (11)	0.0167 (11)	−0.0080 (9)	−0.0015 (9)	0.0008 (9)
C7	0.0123 (10)	0.0164 (11)	0.0199 (12)	−0.0056 (9)	−0.0030 (9)	−0.0027 (9)
C8	0.0166 (11)	0.0181 (11)	0.0205 (12)	−0.0099 (9)	−0.0030 (9)	−0.0009 (9)
C9	0.0159 (11)	0.0254 (12)	0.0220 (12)	−0.0087 (10)	−0.0009 (9)	−0.0078 (10)
C10	0.0171 (12)	0.0206 (12)	0.0332 (15)	−0.0067 (10)	−0.0020 (10)	−0.0094 (11)
C11	0.0176 (12)	0.0161 (11)	0.0367 (15)	−0.0069 (10)	−0.0060 (11)	−0.0007 (10)
C12	0.0179 (12)	0.0202 (12)	0.0227 (12)	−0.0092 (10)	−0.0032 (9)	0.0005 (9)
C13	0.0125 (11)	0.0173 (11)	0.0266 (13)	−0.0040 (9)	0.0015 (9)	−0.0021 (10)
C14	0.0195 (13)	0.0428 (16)	0.0296 (14)	−0.0185 (12)	−0.0075 (11)	0.0053 (12)
C15	0.0236 (13)	0.0294 (13)	0.0174 (12)	−0.0141 (11)	−0.0011 (10)	−0.0051 (10)

Geometric parameters (Å, º)

Cr—C14	1.845 (3)	C3—C4	1.406 (4)
Cr—C13	1.850 (3)	C3—H3	0.9500
Cr—C15	1.853 (3)	C4—C5	1.408 (4)
Cr—C6	2.221 (2)	C4—H4	0.9500
Cr—C5	2.221 (2)	C5—C6	1.413 (3)
Cr—C2	2.222 (2)	C5—H5	0.9500
Cr—C4	2.222 (3)	C6—H6	0.9500
Cr—C3	2.228 (2)	C7—C8	1.396 (3)
Cr—C1	2.238 (2)	C7—C12	1.406 (3)
Br—C8	1.892 (2)	C8—C9	1.399 (3)
O1—C13	1.152 (3)	C9—C10	1.393 (4)
O2—C14	1.158 (4)	C9—H9	0.9500
O3—C15	1.155 (3)	C10—C11	1.383 (4)
C1—C2	1.408 (3)	C10—H10	0.9500
C1—C6	1.433 (3)	C11—C12	1.387 (4)
C1—C7	1.497 (3)	C11—H11	0.9500
C2—C3	1.421 (4)	C12—H12	0.9500
C2—H2	0.9500
C14—Cr—C13	89.71 (13)	Cr—C2—H2	129.1
C14—Cr—C15	88.06 (13)	C4—C3—C2	119.6 (2)
C13—Cr—C15	87.92 (11)	C4—C3—Cr	71.35 (14)
C14—Cr—C6	151.15 (12)	C2—C3—Cr	71.13 (14)
C13—Cr—C6	88.90 (10)	C4—C3—H3	120.2
C15—Cr—C6	120.68 (10)	C2—C3—H3	120.2
C14—Cr—C5	156.58 (12)	Cr—C3—H3	129.7
C13—Cr—C5	113.71 (11)	C3—C4—C5	120.4 (2)
C15—Cr—C5	93.02 (11)	C3—C4—Cr	71.82 (15)
C6—Cr—C5	37.09 (9)	C5—C4—Cr	71.50 (14)
C14—Cr—C2	89.31 (11)	C3—C4—H4	119.8
C13—Cr—C2	120.17 (10)	C5—C4—H4	119.8
C15—Cr—C2	151.77 (11)	Cr—C4—H4	129.3
C6—Cr—C2	66.79 (9)	C4—C5—C6	120.2 (2)
C5—Cr—C2	78.76 (9)	C4—C5—Cr	71.57 (15)
C14—Cr—C4	119.71 (12)	C6—C5—Cr	71.43 (14)
C13—Cr—C4	150.48 (11)	C4—C5—H5	119.9
C15—Cr—C4	90.47 (11)	C6—C5—H5	119.9
C6—Cr—C4	66.78 (10)	Cr—C5—H5	129.6
C5—Cr—C4	36.93 (10)	C5—C6—C1	120.1 (2)
C2—Cr—C4	66.69 (9)	C5—C6—Cr	71.48 (14)
C14—Cr—C3	91.79 (11)	C1—C6—Cr	71.90 (13)
C13—Cr—C3	157.31 (10)	C5—C6—H6	120.0
C15—Cr—C3	114.76 (11)	C1—C6—H6	120.0
C6—Cr—C3	78.99 (9)	Cr—C6—H6	129.0
C5—Cr—C3	66.55 (10)	C8—C7—C12	117.2 (2)
C2—Cr—C3	37.25 (9)	C8—C7—C1	122.6 (2)
C4—Cr—C3	36.83 (10)	C12—C7—C1	120.2 (2)
C14—Cr—C1	113.80 (11)	C7—C8—C9	122.2 (2)
C13—Cr—C1	91.83 (10)	C7—C8—Br	121.29 (18)
C15—Cr—C1	158.14 (11)	C9—C8—Br	116.49 (19)
C6—Cr—C1	37.49 (8)	C10—C9—C8	118.7 (2)
C5—Cr—C1	67.13 (9)	C10—C9—H9	120.7
C2—Cr—C1	36.81 (9)	C8—C9—H9	120.7
C4—Cr—C1	79.08 (9)	C11—C10—C9	120.5 (2)
C3—Cr—C1	66.91 (9)	C11—C10—H10	119.7
C2—C1—C6	118.8 (2)	C9—C10—H10	119.7
C2—C1—C7	119.7 (2)	C10—C11—C12	120.0 (2)
C6—C1—C7	121.5 (2)	C10—C11—H11	120.0
C2—C1—Cr	70.98 (14)	C12—C11—H11	120.0
C6—C1—Cr	70.61 (13)	C11—C12—C7	121.3 (2)
C7—C1—Cr	129.21 (16)	C11—C12—H12	119.3
C1—C2—C3	121.0 (2)	C7—C12—H12	119.3
C1—C2—Cr	72.21 (13)	O1—C13—Cr	179.2 (2)
C3—C2—Cr	71.62 (14)	O2—C14—Cr	179.5 (3)
C1—C2—H2	119.5	O3—C15—Cr	179.2 (2)
C3—C2—H2	119.5
C14—Cr—C1—C2	−52.32 (18)	C2—Cr—C4—C3	−29.47 (14)
C13—Cr—C1—C2	−142.81 (15)	C1—Cr—C4—C3	−65.88 (15)
C15—Cr—C1—C2	128.2 (3)	C14—Cr—C4—C5	177.58 (16)
C6—Cr—C1—C2	131.4 (2)	C13—Cr—C4—C5	−7.8 (3)
C5—Cr—C1—C2	102.16 (16)	C15—Cr—C4—C5	−94.39 (16)
C4—Cr—C1—C2	65.49 (15)	C6—Cr—C4—C5	29.09 (14)
C3—Cr—C1—C2	29.00 (14)	C2—Cr—C4—C5	102.70 (16)
C14—Cr—C1—C6	176.28 (16)	C3—Cr—C4—C5	132.2 (2)
C13—Cr—C1—C6	85.79 (15)	C1—Cr—C4—C5	66.29 (15)
C15—Cr—C1—C6	−3.2 (3)	C3—C4—C5—C6	0.4 (4)
C5—Cr—C1—C6	−29.24 (14)	Cr—C4—C5—C6	−54.4 (2)
C2—Cr—C1—C6	−131.4 (2)	C3—C4—C5—Cr	54.7 (2)
C4—Cr—C1—C6	−65.91 (15)	C14—Cr—C5—C4	−5.3 (4)
C3—Cr—C1—C6	−102.40 (16)	C13—Cr—C5—C4	175.82 (15)
C14—Cr—C1—C7	61.0 (2)	C15—Cr—C5—C4	86.77 (16)
C13—Cr—C1—C7	−29.5 (2)	C6—Cr—C5—C4	−132.2 (2)
C15—Cr—C1—C7	−118.5 (3)	C2—Cr—C5—C4	−65.99 (15)
C6—Cr—C1—C7	−115.3 (3)	C3—Cr—C5—C4	−28.97 (14)
C5—Cr—C1—C7	−144.5 (2)	C1—Cr—C5—C4	−102.65 (16)
C2—Cr—C1—C7	113.3 (3)	C14—Cr—C5—C6	126.9 (3)
C4—Cr—C1—C7	178.8 (2)	C13—Cr—C5—C6	−51.99 (17)
C3—Cr—C1—C7	142.3 (2)	C15—Cr—C5—C6	−141.04 (16)
C6—C1—C2—C3	−0.8 (3)	C2—Cr—C5—C6	66.20 (15)
C7—C1—C2—C3	−179.6 (2)	C4—Cr—C5—C6	132.2 (2)
Cr—C1—C2—C3	−54.6 (2)	C3—Cr—C5—C6	103.23 (16)
C6—C1—C2—Cr	53.84 (19)	C1—Cr—C5—C6	29.54 (14)
C7—C1—C2—Cr	−125.0 (2)	C4—C5—C6—C1	−0.6 (4)
C14—Cr—C2—C1	133.60 (16)	Cr—C5—C6—C1	−55.1 (2)
C13—Cr—C2—C1	44.34 (18)	C4—C5—C6—Cr	54.4 (2)
C15—Cr—C2—C1	−141.8 (2)	C2—C1—C6—C5	0.9 (3)
C6—Cr—C2—C1	−29.78 (13)	C7—C1—C6—C5	179.6 (2)
C5—Cr—C2—C1	−66.68 (14)	Cr—C1—C6—C5	54.9 (2)
C4—Cr—C2—C1	−103.39 (16)	C2—C1—C6—Cr	−54.02 (19)
C3—Cr—C2—C1	−132.5 (2)	C7—C1—C6—Cr	124.8 (2)
C14—Cr—C2—C3	−93.86 (17)	C14—Cr—C6—C5	−138.8 (2)
C13—Cr—C2—C3	176.88 (15)	C13—Cr—C6—C5	133.82 (16)
C15—Cr—C2—C3	−9.3 (3)	C15—Cr—C6—C5	46.90 (19)
C6—Cr—C2—C3	102.76 (16)	C2—Cr—C6—C5	−102.45 (16)
C5—Cr—C2—C3	65.86 (15)	C4—Cr—C6—C5	−28.98 (15)
C4—Cr—C2—C3	29.15 (15)	C3—Cr—C6—C5	−65.48 (15)
C1—Cr—C2—C3	132.5 (2)	C1—Cr—C6—C5	−131.7 (2)
C1—C2—C3—C4	0.5 (4)	C14—Cr—C6—C1	−7.1 (3)
Cr—C2—C3—C4	−54.4 (2)	C13—Cr—C6—C1	−94.46 (15)
C1—C2—C3—Cr	54.9 (2)	C15—Cr—C6—C1	178.62 (14)
C14—Cr—C3—C4	−141.77 (18)	C5—Cr—C6—C1	131.7 (2)
C13—Cr—C3—C4	124.7 (3)	C2—Cr—C6—C1	29.27 (14)
C15—Cr—C3—C4	−53.08 (18)	C4—Cr—C6—C1	102.75 (16)
C6—Cr—C3—C4	65.78 (16)	C3—Cr—C6—C1	66.25 (15)
C5—Cr—C3—C4	29.05 (15)	C2—C1—C7—C8	−120.5 (3)
C2—Cr—C3—C4	131.7 (2)	C6—C1—C7—C8	60.7 (3)
C1—Cr—C3—C4	103.05 (16)	Cr—C1—C7—C8	150.49 (19)
C14—Cr—C3—C2	86.51 (17)	C2—C1—C7—C12	57.2 (3)
C13—Cr—C3—C2	−7.0 (3)	C6—C1—C7—C12	−121.6 (3)
C15—Cr—C3—C2	175.20 (15)	Cr—C1—C7—C12	−31.7 (3)
C6—Cr—C3—C2	−65.94 (15)	C12—C7—C8—C9	0.3 (3)
C5—Cr—C3—C2	−102.67 (16)	C1—C7—C8—C9	178.1 (2)
C4—Cr—C3—C2	−131.7 (2)	C12—C7—C8—Br	−178.19 (18)
C1—Cr—C3—C2	−28.68 (14)	C1—C7—C8—Br	−0.4 (3)
C2—C3—C4—C5	−0.3 (4)	C7—C8—C9—C10	−0.2 (4)
Cr—C3—C4—C5	−54.6 (2)	Br—C8—C9—C10	178.38 (19)
C2—C3—C4—Cr	54.3 (2)	C8—C9—C10—C11	−0.2 (4)
C14—Cr—C4—C3	45.41 (19)	C9—C10—C11—C12	0.4 (4)
C13—Cr—C4—C3	−139.9 (2)	C10—C11—C12—C7	−0.3 (4)
C15—Cr—C4—C3	133.44 (16)	C8—C7—C12—C11	0.0 (4)
C6—Cr—C4—C3	−103.08 (16)	C1—C7—C12—C11	−177.9 (2)
C5—Cr—C4—C3	−132.2 (2)