metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

3,3′-Bis(4-fluoro­benz­yl)-1,1′-ethyl­enediimidazolium tri­bromidocuprate(I)

aNational Changhua University of Education, Department of Chemistry, Changhua 50058, Taiwan
*Correspondence e-mail: leehm@cc.ncue.edu.tw

(Received 8 July 2008; accepted 11 July 2008; online 16 July 2008)

The title compound, (C22H22F2N4)[CuBr3], crystallizes with the cation situated on an inversion center and the anion on a twofold rotation axis along one Cu—Br bond. The two imidazole rings are in an anti configuration. The anion has a trigonal planar coordination geometry.

Related literature

For general background, see: Liao et al. (2007[Liao, C.-Y., Chan, K.-T., Zeng, J.-Y., Hu, C.-H., Tu, C.-Y. & Lee, H. M. (2007). Organometallics, 26, 1692-1702.]). For the structure of another salt of this cation, see: Lee et al. (2007[Lee, H. M., Chen, C.-Y., Chen, W.-L. & Lin, H.-C. (2007). Acta Cryst. E63, o315-o316.]).

[Scheme 1]

Experimental

Crystal data
  • (C22H22F2N4)[CuBr3]

  • Mr = 683.71

  • Monoclinic, C 2/c

  • a = 15.4994 (11) Å

  • b = 11.0825 (8) Å

  • c = 15.4464 (12) Å

  • β = 117.582 (4)°

  • V = 2351.7 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 6.06 mm−1

  • T = 150 (2) K

  • 0.30 × 0.21 × 0.19 mm

Data collection
  • Bruker SMART 1000 diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001[Sheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.]) Tmin = 0.213, Tmax = 0.318

  • 11647 measured reflections

  • 2686 independent reflections

  • 2242 reflections with I > 2σ(I)

  • Rint = 0.023

Refinement
  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.091

  • S = 1.03

  • 2686 reflections

  • 146 parameters

  • H-atom parameters constrained

  • Δρmax = 1.51 e Å−3

  • Δρmin = −0.73 e Å−3

Table 1
Selected geometric parameters (Å, °)

Cu1—Br2 2.3314 (9)
Cu1—Br1 2.3869 (5)
Br2—Cu1—Br1 123.349 (16)
Br1—Cu1—Br1i 113.30 (3)
Symmetry code: (i) [-x+1, y, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Our group is interested in the preparation of imidazolium salts, which can be employed as ligand precursors for N-heterocyclic carbenes (Liao et al., 2007). In an unsuccessful attempt to prepare a copper carbene complex using 1,1'-bis(4-fluorobenzyl)-3,3'-ethylenediimidazolium dibromide, we isolated the title compound (I). Here we present its structure (Fig. 1). In our previous work (Lee et al., 2007), we reported the structure of 1,1'-bis(4-fluorobenzyl)-3,3'-ethylenediimidazolium dichloride monohydrate (II), which features the same imidazolium cation with chloride anions.

Compound (I) crystallizes in the monoclinic space group C2/c with the imidazolium cation situated on a center of inversion. An notable feature is the anti configuration of the two imdazole rings, which is in contrast to the structure of (II). Also, there is no guest water incorporation as in the structure of (II). The anion lies on a twofold rotation axis and has trigonal-planar geometry.

Related literature top

For general background, see: Liao et al. (2007). For the structure of another salt of this cation, see: Lee et al. (2007).

Experimental top

The compound was prepared by heating a mixture of 1,1'-bis(4-fluorobenzyl)-3,3'-ethylenediimidazolium dibromide (0.10 g, 18.5 mmol), copper dibromide (0.0496 g, 22.2 mmol), and sodium acetate (0.0304 g, 37.0 mmol) in DMSO (5 ml) at 353 K for 4 h. After cooling, the solvent was removed completely under vacuum. The residual solid was washed with water and dichloromethane. Crystals were obtained by vapor diffusion of diethyl ether into a DMF solution of the compound.

Refinement top

All H atoms were positioned geometrically and refined with a riding model, with Uiso(H) = 1.5Ueq(C) for methyl H atoms and 1.2Ueq(C) for all other H atoms.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of (I), showing 50% probability displacement ellipsoids for non-H atoms. H atoms are of arbitrary size. Unlabeled atoms of the imidazolium cation are related to labeled atoms by 3/2-x, 3/2-y, -z; for the anion, the symmetry operation for Br1 is 1-x + 1, y, 1/2-z.
3,3'-Bis(4-fluorobenzyl)-1,1'-ethylenediimidazolium tribromidocuprate(I) top
Crystal data top
(C22H22F2N4)[CuBr3]F(000) = 1336
Mr = 683.71Dx = 1.931 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3837 reflections
a = 15.4994 (11) Åθ = 2.4–27.1°
b = 11.0825 (8) ŵ = 6.06 mm1
c = 15.4464 (12) ÅT = 150 K
β = 117.582 (4)°Prism, colorless
V = 2351.7 (3) Å30.30 × 0.21 × 0.19 mm
Z = 4
Data collection top
Bruker SMART 1000
diffractometer
2686 independent reflections
Radiation source: fine-focus sealed tube2242 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
Detector resolution: 8.3 pixels mm-1θmax = 27.5°, θmin = 2.4°
ω scansh = 2020
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)
k = 1414
Tmin = 0.214, Tmax = 0.318l = 2020
11647 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.091H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0522P)2 + 7.4402P]
where P = (Fo2 + 2Fc2)/3
2686 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 1.51 e Å3
0 restraintsΔρmin = 0.74 e Å3
Crystal data top
(C22H22F2N4)[CuBr3]V = 2351.7 (3) Å3
Mr = 683.71Z = 4
Monoclinic, C2/cMo Kα radiation
a = 15.4994 (11) ŵ = 6.06 mm1
b = 11.0825 (8) ÅT = 150 K
c = 15.4464 (12) Å0.30 × 0.21 × 0.19 mm
β = 117.582 (4)°
Data collection top
Bruker SMART 1000
diffractometer
2686 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)
2242 reflections with I > 2σ(I)
Tmin = 0.214, Tmax = 0.318Rint = 0.023
11647 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.091H-atom parameters constrained
S = 1.03Δρmax = 1.51 e Å3
2686 reflectionsΔρmin = 0.74 e Å3
146 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
xyzUiso*/Ueq
Cu10.50000.18316 (6)0.25000.03387 (17)
Br10.48562 (2)0.06476 (3)0.11487 (2)0.02810 (12)
Br20.50000.39352 (5)0.25000.03037 (14)
F10.8176 (2)0.0493 (2)0.03890 (16)0.0474 (6)
N10.71155 (19)0.6850 (2)0.08805 (18)0.0213 (6)
N20.7085 (2)0.5320 (2)0.17325 (18)0.0213 (5)
C10.7483 (2)0.7770 (3)0.0448 (2)0.0224 (6)
H1A0.81430.80300.09330.027*
H1B0.70500.84840.02540.027*
C20.7660 (2)0.6007 (3)0.1510 (2)0.0241 (7)
H2A0.83430.59110.17590.029*
C30.6162 (2)0.6686 (3)0.0690 (3)0.0286 (7)
H3A0.56180.71580.02640.034*
C40.6148 (3)0.5730 (3)0.1223 (3)0.0287 (7)
H4A0.55910.54010.12410.034*
C50.7439 (3)0.4259 (3)0.2389 (2)0.0254 (7)
H5A0.69410.40140.25860.030*
H5B0.80390.44780.29860.030*
C60.7651 (2)0.3216 (3)0.1889 (2)0.0229 (7)
C70.6915 (3)0.2417 (3)0.1315 (2)0.0290 (7)
H7A0.62860.25090.12680.035*
C80.7084 (3)0.1489 (3)0.0809 (3)0.0355 (9)
H8A0.65810.09450.04160.043*
C90.8001 (3)0.1388 (3)0.0898 (2)0.0325 (8)
C100.8756 (3)0.2142 (3)0.1463 (3)0.0324 (8)
H10A0.93860.20330.15130.039*
C110.8573 (2)0.3071 (3)0.1961 (2)0.0268 (7)
H11A0.90820.36100.23520.032*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.0247 (3)0.0338 (4)0.0381 (3)0.0000.0102 (3)0.000
Br10.02629 (19)0.0309 (2)0.02709 (18)0.00222 (13)0.01230 (14)0.00081 (13)
Br20.0272 (2)0.0304 (3)0.0374 (3)0.0000.0182 (2)0.000
F10.0816 (19)0.0265 (12)0.0329 (11)0.0060 (11)0.0254 (12)0.0055 (9)
N10.0236 (13)0.0230 (14)0.0183 (12)0.0005 (11)0.0107 (10)0.0001 (10)
N20.0242 (13)0.0216 (13)0.0204 (12)0.0010 (11)0.0123 (10)0.0022 (10)
C10.0282 (16)0.0202 (16)0.0216 (14)0.0029 (13)0.0138 (12)0.0006 (12)
C20.0242 (16)0.0266 (17)0.0220 (15)0.0003 (13)0.0112 (12)0.0039 (12)
C30.0228 (16)0.0292 (18)0.0350 (18)0.0036 (14)0.0144 (14)0.0086 (14)
C40.0233 (16)0.0311 (18)0.0371 (18)0.0013 (14)0.0185 (14)0.0046 (15)
C50.0322 (18)0.0232 (17)0.0238 (15)0.0011 (14)0.0156 (14)0.0059 (13)
C60.0271 (16)0.0210 (16)0.0208 (14)0.0014 (13)0.0112 (12)0.0042 (12)
C70.0268 (17)0.0274 (18)0.0300 (17)0.0066 (14)0.0107 (13)0.0044 (14)
C80.044 (2)0.0245 (18)0.0269 (17)0.0103 (16)0.0068 (15)0.0037 (14)
C90.055 (2)0.0176 (16)0.0223 (15)0.0036 (16)0.0151 (15)0.0021 (13)
C100.0349 (19)0.031 (2)0.0313 (17)0.0040 (15)0.0155 (15)0.0002 (15)
C110.0260 (17)0.0248 (17)0.0259 (15)0.0017 (13)0.0089 (13)0.0024 (13)
Geometric parameters (Å, º) top
Cu1—Br22.3314 (9)C3—H3A0.950
Cu1—Br12.3869 (5)C4—H4A0.950
Cu1—Br1i2.3869 (5)C5—C61.508 (5)
F1—C91.368 (4)C5—H5A0.990
N1—C21.331 (4)C5—H5B0.990
N1—C31.379 (4)C6—C71.390 (5)
N1—C11.470 (4)C6—C111.391 (5)
N2—C21.333 (4)C7—C81.388 (6)
N2—C41.370 (4)C7—H7A0.950
N2—C51.482 (4)C8—C91.369 (6)
C1—C1ii1.532 (6)C8—H8A0.950
C1—H1A0.990C9—C101.373 (5)
C1—H1B0.990C10—C111.390 (5)
C2—H2A0.950C10—H10A0.950
C3—C41.349 (5)C11—H11A0.950
Br2—Cu1—Br1123.349 (16)N2—C5—C6110.9 (3)
Br2—Cu1—Br1i123.349 (16)N2—C5—H5A109.5
Br1—Cu1—Br1i113.30 (3)C6—C5—H5A109.5
C2—N1—C3108.6 (3)N2—C5—H5B109.5
C2—N1—C1124.8 (3)C6—C5—H5B109.5
C3—N1—C1126.6 (3)H5A—C5—H5B108.0
C2—N2—C4108.7 (3)C7—C6—C11119.1 (3)
C2—N2—C5123.3 (3)C7—C6—C5120.4 (3)
C4—N2—C5127.9 (3)C11—C6—C5120.5 (3)
N1—C1—C1ii108.8 (3)C8—C7—C6121.2 (3)
N1—C1—H1A109.9C8—C7—H7A119.4
C1ii—C1—H1A109.9C6—C7—H7A119.4
N1—C1—H1B109.9C9—C8—C7117.5 (3)
C1ii—C1—H1B109.9C9—C8—H8A121.2
H1A—C1—H1B108.3C7—C8—H8A121.2
N1—C2—N2108.4 (3)F1—C9—C8118.3 (3)
N1—C2—H2A125.8F1—C9—C10118.0 (4)
N2—C2—H2A125.8C8—C9—C10123.6 (4)
C4—C3—N1107.0 (3)C9—C10—C11118.0 (4)
C4—C3—H3A126.5C9—C10—H10A121.0
N1—C3—H3A126.5C11—C10—H10A121.0
C3—C4—N2107.4 (3)C10—C11—C6120.5 (3)
C3—C4—H4A126.3C10—C11—H11A119.8
N2—C4—H4A126.3C6—C11—H11A119.8
Symmetry codes: (i) x+1, y, z+1/2; (ii) x+3/2, y+3/2, z.

Experimental details

Crystal data
Chemical formula(C22H22F2N4)[CuBr3]
Mr683.71
Crystal system, space groupMonoclinic, C2/c
Temperature (K)150
a, b, c (Å)15.4994 (11), 11.0825 (8), 15.4464 (12)
β (°) 117.582 (4)
V3)2351.7 (3)
Z4
Radiation typeMo Kα
µ (mm1)6.06
Crystal size (mm)0.30 × 0.21 × 0.19
Data collection
DiffractometerBruker SMART 1000
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2001)
Tmin, Tmax0.214, 0.318
No. of measured, independent and
observed [I > 2σ(I)] reflections
11647, 2686, 2242
Rint0.023
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.091, 1.03
No. of reflections2686
No. of parameters146
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.51, 0.74

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL (Sheldrick, 2008).

Selected geometric parameters (Å, º) top
Cu1—Br22.3314 (9)Cu1—Br12.3869 (5)
Br2—Cu1—Br1123.349 (16)Br1—Cu1—Br1i113.30 (3)
Symmetry code: (i) x+1, y, z+1/2.
 

Acknowledgements

The authors are grateful to the National Science Council of Taiwan for financial support of this work.

References

First citationBruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationLee, H. M., Chen, C.-Y., Chen, W.-L. & Lin, H.-C. (2007). Acta Cryst. E63, o315–o316.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationLiao, C.-Y., Chan, K.-T., Zeng, J.-Y., Hu, C.-H., Tu, C.-Y. & Lee, H. M. (2007). Organometallics, 26, 1692–1702.  Web of Science CSD CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds