metal-organic compounds
Dibromido(6,6′-dimethyl-2,2′-bipyridine-κ2N,N′)cadmium
aDepartment of Chemistry, Islamic Azad University, Omidieh Branch, Omidieh, Iran
*Correspondence e-mail: sadif_shirvan1@yahoo.com
In the title compound, [CdBr2(C12H12N2)], the CdII atom is four-coordinated in a distorted tetrahedral geometry by two N atoms from a 6,6′-dimethyl-2,2′-bipyridine ligand and two terminal Br atoms. In the crystal, C—H⋯Br hydrogen bonds and π–π stacking interactions between the pyridine rings [centroid–centroid distance = 3.763 (5) Å] are present.
Related literature
For related structures, see: Akbarzadeh Torbati et al. (2010); Alizadeh et al. (2010, 2011); Alizadeh, Kalateh, Ebadi et al. (2009); Alizadeh, Kalateh, Khoshtarkib et al. (2009); Alizadeh, Khoshtarkib et al. (2009); Itoh et al. (2005); Kou et al. (2008); Onggo et al. (2005); Shirvan & Haydari Dezfuli (2012a,b).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2007); cell SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).
Supporting information
10.1107/S1600536812033648/hy2576sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812033648/hy2576Isup2.hkl
For the preparation of the title compound, a solution of 6,6'-dimethyl-2,2'-bipyridine (0.25 g, 1.33 mmol) in methanol (10 ml) was added to a solution of CdBr2.4H2O (0.46 g, 1.33 mmol) in methanol (10 ml) at room temperature. Crystals suitable for X-ray diffraction experiment were obtained by methanol diffusion into a colorless solution in DMSO after one week (yield: 0.47 g, 77.4%).
H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.93 (aromatic) and 0.96 (CH3) Å and with Uiso(H) = 1.2Ueq(C).
Data collection: APEX2 (Bruker, 2007); cell
SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[CdBr2(C12H12N2)] | F(000) = 864 |
Mr = 456.45 | Dx = 2.087 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 11844 reflections |
a = 7.7606 (11) Å | θ = 2.3–26.0° |
b = 10.3832 (17) Å | µ = 6.98 mm−1 |
c = 18.184 (2) Å | T = 298 K |
β = 97.460 (11)° | Block, colorless |
V = 1452.8 (4) Å3 | 0.40 × 0.20 × 0.15 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 2862 independent reflections |
Radiation source: fine-focus sealed tube | 1945 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.098 |
ϕ and ω scans | θmax = 26.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | h = −9→9 |
Tmin = 0.054, Tmax = 0.155 | k = −12→12 |
11844 measured reflections | l = −19→22 |
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)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.124 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0602P)2] where P = (Fo2 + 2Fc2)/3 |
2862 reflections | (Δ/σ)max = 0.003 |
154 parameters | Δρmax = 0.61 e Å−3 |
0 restraints | Δρmin = −0.78 e Å−3 |
[CdBr2(C12H12N2)] | V = 1452.8 (4) Å3 |
Mr = 456.45 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.7606 (11) Å | µ = 6.98 mm−1 |
b = 10.3832 (17) Å | T = 298 K |
c = 18.184 (2) Å | 0.40 × 0.20 × 0.15 mm |
β = 97.460 (11)° |
Bruker APEXII CCD diffractometer | 2862 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2001) | 1945 reflections with I > 2σ(I) |
Tmin = 0.054, Tmax = 0.155 | Rint = 0.098 |
11844 measured reflections |
R[F2 > 2σ(F2)] = 0.047 | 0 restraints |
wR(F2) = 0.124 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.61 e Å−3 |
2862 reflections | Δρmin = −0.78 e Å−3 |
154 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
C1 | 0.1386 (14) | 0.4345 (10) | 0.2292 (5) | 0.081 (3) | |
H1A | 0.2494 | 0.3951 | 0.2444 | 0.098* | |
H1B | 0.0530 | 0.3689 | 0.2161 | 0.098* | |
H1C | 0.1055 | 0.4852 | 0.2693 | 0.098* | |
C2 | 0.1505 (10) | 0.5178 (8) | 0.1648 (5) | 0.060 (2) | |
C3 | 0.1116 (12) | 0.6486 (9) | 0.1659 (6) | 0.077 (3) | |
H3 | 0.0782 | 0.6861 | 0.2083 | 0.092* | |
C4 | 0.1230 (12) | 0.7210 (8) | 0.1044 (7) | 0.078 (3) | |
H4 | 0.0963 | 0.8083 | 0.1044 | 0.094* | |
C5 | 0.1750 (11) | 0.6642 (8) | 0.0409 (6) | 0.071 (3) | |
H5 | 0.1835 | 0.7133 | −0.0013 | 0.085* | |
C6 | 0.2136 (9) | 0.5334 (7) | 0.0417 (4) | 0.0483 (17) | |
C7 | 0.2699 (8) | 0.4638 (7) | −0.0232 (4) | 0.0461 (17) | |
C8 | 0.2878 (11) | 0.5254 (9) | −0.0896 (5) | 0.066 (2) | |
H8 | 0.2613 | 0.6124 | −0.0958 | 0.079* | |
C9 | 0.3445 (11) | 0.4568 (11) | −0.1454 (5) | 0.072 (3) | |
H9 | 0.3569 | 0.4969 | −0.1902 | 0.087* | |
C10 | 0.3835 (11) | 0.3288 (11) | −0.1359 (5) | 0.070 (3) | |
H10 | 0.4226 | 0.2818 | −0.1740 | 0.084* | |
C11 | 0.3646 (10) | 0.2703 (8) | −0.0699 (5) | 0.0543 (19) | |
C12 | 0.4037 (14) | 0.1324 (10) | −0.0560 (6) | 0.080 (3) | |
H12A | 0.3013 | 0.0891 | −0.0446 | 0.095* | |
H12B | 0.4944 | 0.1241 | −0.0150 | 0.095* | |
H12C | 0.4410 | 0.0945 | −0.0995 | 0.095* | |
N1 | 0.1993 (7) | 0.4635 (6) | 0.1027 (3) | 0.0470 (14) | |
N2 | 0.3092 (7) | 0.3379 (6) | −0.0136 (3) | 0.0448 (13) | |
Cd1 | 0.27194 (7) | 0.25065 (5) | 0.09801 (3) | 0.04813 (18) | |
Br1 | 0.01860 (13) | 0.10203 (9) | 0.10288 (6) | 0.0775 (3) | |
Br2 | 0.54796 (12) | 0.18801 (10) | 0.17765 (5) | 0.0693 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.105 (7) | 0.093 (7) | 0.049 (5) | 0.005 (6) | 0.024 (5) | −0.017 (5) |
C2 | 0.053 (5) | 0.056 (5) | 0.069 (6) | 0.005 (4) | −0.001 (4) | −0.020 (4) |
C3 | 0.074 (6) | 0.058 (6) | 0.095 (8) | 0.011 (5) | −0.002 (5) | −0.019 (5) |
C4 | 0.064 (5) | 0.040 (5) | 0.123 (9) | 0.016 (4) | −0.022 (6) | −0.027 (5) |
C5 | 0.063 (5) | 0.042 (4) | 0.099 (7) | −0.005 (4) | −0.023 (5) | 0.011 (5) |
C6 | 0.042 (4) | 0.039 (4) | 0.060 (5) | −0.002 (3) | −0.010 (3) | 0.004 (3) |
C7 | 0.039 (4) | 0.049 (4) | 0.048 (4) | −0.011 (3) | −0.003 (3) | 0.011 (3) |
C8 | 0.062 (5) | 0.069 (6) | 0.066 (6) | −0.011 (4) | 0.002 (4) | 0.023 (5) |
C9 | 0.066 (5) | 0.103 (8) | 0.048 (5) | −0.017 (5) | 0.006 (4) | 0.020 (5) |
C10 | 0.060 (5) | 0.109 (8) | 0.042 (4) | −0.019 (5) | 0.007 (4) | −0.003 (5) |
C11 | 0.055 (4) | 0.060 (5) | 0.048 (4) | −0.002 (4) | 0.009 (4) | −0.005 (4) |
C12 | 0.093 (7) | 0.079 (7) | 0.067 (6) | 0.007 (5) | 0.013 (5) | −0.019 (5) |
N1 | 0.042 (3) | 0.048 (3) | 0.051 (4) | −0.001 (3) | 0.002 (3) | −0.007 (3) |
N2 | 0.047 (3) | 0.046 (3) | 0.041 (3) | −0.008 (3) | 0.004 (3) | 0.001 (3) |
Cd1 | 0.0576 (3) | 0.0421 (3) | 0.0456 (3) | 0.0049 (3) | 0.0102 (2) | 0.0069 (2) |
Br1 | 0.0804 (6) | 0.0631 (6) | 0.0900 (7) | −0.0163 (5) | 0.0155 (5) | 0.0197 (5) |
Br2 | 0.0661 (5) | 0.0808 (6) | 0.0597 (5) | 0.0161 (5) | 0.0033 (4) | 0.0171 (5) |
C1—C2 | 1.469 (13) | C8—C9 | 1.358 (14) |
C1—H1A | 0.9600 | C8—H8 | 0.9300 |
C1—H1B | 0.9600 | C9—C10 | 1.369 (15) |
C1—H1C | 0.9600 | C9—H9 | 0.9300 |
C2—N1 | 1.360 (10) | C10—C11 | 1.369 (12) |
C2—C3 | 1.392 (13) | C10—H10 | 0.9300 |
C3—C4 | 1.360 (15) | C11—N2 | 1.357 (10) |
C3—H3 | 0.9300 | C11—C12 | 1.479 (12) |
C4—C5 | 1.402 (14) | C12—H12A | 0.9600 |
C4—H4 | 0.9300 | C12—H12B | 0.9600 |
C5—C6 | 1.390 (11) | C12—H12C | 0.9600 |
C5—H5 | 0.9300 | N1—Cd1 | 2.285 (6) |
C6—N1 | 1.341 (10) | N2—Cd1 | 2.274 (6) |
C6—C7 | 1.498 (11) | Cd1—Br1 | 2.5099 (11) |
C7—N2 | 1.349 (9) | Cd1—Br2 | 2.5106 (11) |
C7—C8 | 1.389 (11) | ||
C2—C1—H1A | 109.5 | C8—C9—C10 | 120.1 (8) |
C2—C1—H1B | 109.5 | C8—C9—H9 | 119.9 |
H1A—C1—H1B | 109.5 | C10—C9—H9 | 119.9 |
C2—C1—H1C | 109.5 | C9—C10—C11 | 119.6 (9) |
H1A—C1—H1C | 109.5 | C9—C10—H10 | 120.2 |
H1B—C1—H1C | 109.5 | C11—C10—H10 | 120.2 |
N1—C2—C3 | 120.1 (9) | N2—C11—C10 | 120.8 (8) |
N1—C2—C1 | 118.2 (7) | N2—C11—C12 | 116.8 (7) |
C3—C2—C1 | 121.8 (9) | C10—C11—C12 | 122.4 (8) |
C4—C3—C2 | 119.3 (10) | C11—C12—H12A | 109.5 |
C4—C3—H3 | 120.3 | C11—C12—H12B | 109.5 |
C2—C3—H3 | 120.3 | H12A—C12—H12B | 109.5 |
C3—C4—C5 | 120.1 (8) | C11—C12—H12C | 109.5 |
C3—C4—H4 | 119.9 | H12A—C12—H12C | 109.5 |
C5—C4—H4 | 119.9 | H12B—C12—H12C | 109.5 |
C6—C5—C4 | 119.1 (9) | C6—N1—C2 | 121.6 (7) |
C6—C5—H5 | 120.5 | C6—N1—Cd1 | 116.5 (5) |
C4—C5—H5 | 120.5 | C2—N1—Cd1 | 121.9 (5) |
N1—C6—C5 | 119.8 (8) | C7—N2—C11 | 119.4 (6) |
N1—C6—C7 | 117.0 (6) | C7—N2—Cd1 | 116.7 (5) |
C5—C6—C7 | 123.1 (8) | C11—N2—Cd1 | 123.8 (5) |
N2—C7—C8 | 120.9 (7) | N2—Cd1—N1 | 73.0 (2) |
N2—C7—C6 | 116.7 (6) | N2—Cd1—Br1 | 117.85 (15) |
C8—C7—C6 | 122.4 (7) | N1—Cd1—Br1 | 113.28 (14) |
C9—C8—C7 | 119.1 (9) | N2—Cd1—Br2 | 114.84 (15) |
C9—C8—H8 | 120.4 | N1—Cd1—Br2 | 115.17 (15) |
C7—C8—H8 | 120.4 | Br1—Cd1—Br2 | 115.72 (4) |
N1—C2—C3—C4 | 0.0 (13) | C3—C2—N1—Cd1 | 178.3 (6) |
C1—C2—C3—C4 | −179.3 (9) | C1—C2—N1—Cd1 | −2.4 (10) |
C2—C3—C4—C5 | −0.6 (15) | C8—C7—N2—C11 | −0.9 (10) |
C3—C4—C5—C6 | 0.3 (14) | C6—C7—N2—C11 | −178.6 (7) |
C4—C5—C6—N1 | 0.6 (12) | C8—C7—N2—Cd1 | −179.7 (5) |
C4—C5—C6—C7 | 179.9 (7) | C6—C7—N2—Cd1 | 2.6 (7) |
N1—C6—C7—N2 | −3.0 (9) | C10—C11—N2—C7 | 0.9 (11) |
C5—C6—C7—N2 | 177.7 (7) | C12—C11—N2—C7 | −179.4 (7) |
N1—C6—C7—C8 | 179.3 (7) | C10—C11—N2—Cd1 | 179.7 (6) |
C5—C6—C7—C8 | 0.0 (11) | C12—C11—N2—Cd1 | −0.6 (10) |
N2—C7—C8—C9 | 0.4 (12) | C7—N2—Cd1—N1 | −1.2 (4) |
C6—C7—C8—C9 | 178.0 (7) | C11—N2—Cd1—N1 | 180.0 (6) |
C7—C8—C9—C10 | −0.1 (13) | C7—N2—Cd1—Br1 | 106.6 (4) |
C8—C9—C10—C11 | 0.2 (13) | C11—N2—Cd1—Br1 | −72.2 (6) |
C9—C10—C11—N2 | −0.6 (13) | C7—N2—Cd1—Br2 | −111.6 (4) |
C9—C10—C11—C12 | 179.8 (8) | C11—N2—Cd1—Br2 | 69.6 (6) |
C5—C6—N1—C2 | −1.2 (11) | C6—N1—Cd1—N2 | −0.5 (5) |
C7—C6—N1—C2 | 179.4 (6) | C2—N1—Cd1—N2 | −178.0 (6) |
C5—C6—N1—Cd1 | −178.8 (5) | C6—N1—Cd1—Br1 | −114.1 (5) |
C7—C6—N1—Cd1 | 1.9 (8) | C2—N1—Cd1—Br1 | 68.4 (6) |
C3—C2—N1—C6 | 0.9 (11) | C6—N1—Cd1—Br2 | 109.5 (5) |
C1—C2—N1—C6 | −179.8 (8) | C2—N1—Cd1—Br2 | −68.0 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1C···Br1i | 0.96 | 2.90 | 3.848 (10) | 171 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [CdBr2(C12H12N2)] |
Mr | 456.45 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 7.7606 (11), 10.3832 (17), 18.184 (2) |
β (°) | 97.460 (11) |
V (Å3) | 1452.8 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 6.98 |
Crystal size (mm) | 0.40 × 0.20 × 0.15 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2001) |
Tmin, Tmax | 0.054, 0.155 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 11844, 2862, 1945 |
Rint | 0.098 |
(sin θ/λ)max (Å−1) | 0.617 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.047, 0.124, 1.03 |
No. of reflections | 2862 |
No. of parameters | 154 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.61, −0.78 |
Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2006), SHELXTL (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1C···Br1i | 0.96 | 2.90 | 3.848 (10) | 171 |
Symmetry code: (i) −x, y+1/2, −z+1/2. |
Acknowledgements
We are grateful to the Islamic Azad University, Omidieh Branch, for financial support.
References
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Recently, we reported the synthesis and crystal structures of [Cd(5,5'-dmbpy)(µ-Br)2]n (Shirvan & Haydari Dezfuli, 2012a) and [CdBr2(4,4'-dmbpy)(DMSO)] (Shirvan & Haydari Dezfuli, 2012b) (5,5'-dmbpy = 5,5'-dimethyl-2,2'-bipyridine, 4,4'-dmbpy = 4,4'-dimethyl-2,2'-bipyridine, DMSO = dimethyl sulfoxide). 6,6'-Dimethyl-2,2'-bipyridine (6,6'-dmbipy) is a good bidentate ligand and numerous complexes with 6,6'-dmbipy have been prepared, such as that of zinc (Alizadeh, Kalateh, Ebadi et al., 2009; Alizadeh, Kalateh, Khoshtarkib et al., 2009; Alizadeh, Khoshtarkib et al., 2009), copper (Itoh et al., 2005), cadmium (Alizadeh et al., 2010), cobalt (Akbarzadeh Torbati et al., 2010), nickel (Kou et al., 2008), ruthenium (Onggo et al., 2005) and mercury (Alizadeh et al., 2011). We report herein the synthesis and crystal structure of the title compound.
In the title compound (Fig. 1), the CdII atom is four-coordinated in a distorted tetrahedral geometry by two N atoms from a 6,6'-dimethyl-2,2'-bipyridine ligand and two terminal Br atoms. The crystal structure is stabilized by intermolecular C—H···Br hydrogen bonds (Table 1) and π–π contacts (Fig. 2) between the pyridine rings, Cg2···Cg3i [symmetry code: (i) -x, 1-y, -z. Cg2 and Cg3 are the centroids of the N1/C2–C6 ring and N2/C7–C11 ring], with a centroid–centroid distance of 3.763 (5) Å.