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1,1′-Di-n-butyl-4,4′-bipyridinium 2.375-bromido-1.625-chloridocadmate

aDepartment of Chemistry, Zhengzhou University, Zhengzhou 450052, People's Republic of China, and bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: seikweng@um.edu.my

(Received 3 January 2011; accepted 4 January 2011; online 12 January 2011)

The title salt, (C18H26N2)[CdBr2.375Cl1.625], consists of non-inter­acting cations and tetra­hedral cadmate(II) anions. The halogen atoms are all disordered, the bromine components being in 0.9035 (17):0.0965 (17), 0.6581 (18):0.3419 (18), 0.5019 (19):0.4981 (19) and 0.6847 (19):0.3153 (18) ratios. The aromatic rings of the cation are twisted by 25.0 (1)°.

Related literature

For the synthesis of the cation, see: Hou et al. (2005[Hou, Z.-S., Tan, Y.-B., Xu, J. & Zhou, Q.-F. (2005). Chin. J. Org. Chem. 25, 934-939.]). For a similar disordered tetrahalogenidocadmate, see: Liu et al. (2007[Liu, X.-C., Shi, J., Niu, Y.-Y., Xu, N. & Ng, S. W. (2007). Acta Cryst. E63, m1781.]).

[Scheme 1]

Experimental

Crystal data
  • (C18H26N2)[CdBr2.375Cl1.625]

  • Mr = 630.20

  • Monoclinic, P 21 /c

  • a = 8.6969 (5) Å

  • b = 16.6024 (10) Å

  • c = 16.6881 (10) Å

  • β = 104.936 (1)°

  • V = 2328.2 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 5.21 mm−1

  • T = 100 K

  • 0.30 × 0.30 × 0.10 mm

Data collection
  • Bruker SMART APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.304, Tmax = 0.624

  • 21634 measured reflections

  • 5354 independent reflections

  • 4487 reflections with I > 2σ(I)

  • Rint = 0.045

Refinement
  • R[F2 > 2σ(F2)] = 0.031

  • wR(F2) = 0.078

  • S = 1.02

  • 5354 reflections

  • 234 parameters

  • 5 restraints

  • H-atom parameters constrained

  • Δρmax = 1.49 e Å−3

  • Δρmin = −1.27 e Å−3

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: X-SEED (Barbour, 2001[Barbour, L. J. (2001). J. Supramol. Chem. 1, 189-191.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The class of 1,1'-dialkyl-4,4'-bipyridinium bromides represents a class of ammonium salts that are excellent directing regents for the construction of metal–organic architectures. In a previous study, the reaction of a similar salt, 1,1'-(propane-1,3-diyl)dipyridinium dibromide, with cadmium dichloride, yielded the salt as a dibromidodichlorodocadmate; the halogen atoms are all disordered. In the present study, the reaction of 1,1'-dibutyl-4,4'-bipyridinium dibromide with cadmium dichloride yielded a similarly disordered cadmate counterion whose bromine:chloride ratio is 2.375:1.625 (Scheme I, Fig. 1).

Related literature top

For the synthesis of the cation, see: Hou et al. (2005). For a similar disordered tetrahalogenocadmate, see: Liu et al. (2007).

Experimental top

1,1'-Dibutyl-4,4'-bipyridinium dibromide was synthesized by using a literature method (Hou et al., 2005). 1-Bromobutane (30 mmol, 4.11 g) and 4,4′-bipyridyl (10 mmol, 1.56 g) were dissolved in acetonitrile (20 ml). The solution was heated at 343–353 K for 48 h. The yellow precipitate that formed was collected and recrystallized from a methanol/ether mixture to give a white powder (4.2 g, 90% yield.)

A methanol solution (10 ml) of the dibromide salt (0.43 g, 1.0 mmol) was added to a solution of cadmium dichloride (0.184 g, 1.0 mmol) dissolved in an DMF/H2O (4:1) mixture (10 ml) to precipitiate a white solid. This dissolved when DMF was added. The solution was filtered and then set aside for the growth of colorless crystals (40% yield) after a week. The crystals are not soluble in common solvents.

Refinement top

Hydrogen atoms were placed in calculated positions (C—H 0.95 to 0.99 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2–1.5Ueq(C).

Each halogen site is occupied by a mixture of chlorine and bromine atoms. For each site, the temperate factors for the major and minor occupants were restrained to be identical. As the total occupancy of the bromine atoms refined to nearly 2 3/8, the sum occupany was then fixed as exactly 2 3/8. The final difference Fourier had a peak at 1.83 Å from H2b and a hole at 0.88 ° from Cd1

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of [C18H26N2]2+ [Br2.375Cl1.625Cd]2- at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius. The halogen atoms are all disordered, and are represented as bromide atoms.
1,1'-Di-n-butyl-4,4'-bipyridinium 2.375-bromido-1.625-chloridocadmate top
Crystal data top
(C18H26N2)[CdBr2.375Cl1.625]F(000) = 1227
Mr = 630.20Dx = 1.798 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 8220 reflections
a = 8.6969 (5) Åθ = 2.4–28.3°
b = 16.6024 (10) ŵ = 5.21 mm1
c = 16.6881 (10) ÅT = 100 K
β = 104.936 (1)°Prism, colorless
V = 2328.2 (2) Å30.30 × 0.30 × 0.10 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer
5354 independent reflections
Radiation source: fine-focus sealed tube4487 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.045
ω scansθmax = 27.5°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 1111
Tmin = 0.304, Tmax = 0.624k = 2121
21634 measured reflectionsl = 2121
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)] = 0.031Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.078H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.037P)2 + 2.9972P]
where P = (Fo2 + 2Fc2)/3
5354 reflections(Δ/σ)max = 0.001
234 parametersΔρmax = 1.49 e Å3
5 restraintsΔρmin = 1.27 e Å3
Crystal data top
(C18H26N2)[CdBr2.375Cl1.625]V = 2328.2 (2) Å3
Mr = 630.20Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.6969 (5) ŵ = 5.21 mm1
b = 16.6024 (10) ÅT = 100 K
c = 16.6881 (10) Å0.30 × 0.30 × 0.10 mm
β = 104.936 (1)°
Data collection top
Bruker SMART APEX
diffractometer
5354 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
4487 reflections with I > 2σ(I)
Tmin = 0.304, Tmax = 0.624Rint = 0.045
21634 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0315 restraints
wR(F2) = 0.078H-atom parameters constrained
S = 1.02Δρmax = 1.49 e Å3
5354 reflectionsΔρmin = 1.27 e Å3
234 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Cd10.40196 (3)0.424706 (15)0.232277 (14)0.01974 (7)
Br10.22214 (4)0.35248 (2)0.10618 (2)0.02326 (11)0.9035 (17)
Br20.23823 (5)0.48953 (3)0.32488 (2)0.02183 (13)0.6581 (18)
Br30.62807 (6)0.34583 (3)0.32995 (3)0.02465 (15)0.4981 (19)
Br40.53176 (7)0.53958 (4)0.17615 (3)0.02306 (17)0.3153 (19)
Cl10.22214 (4)0.35248 (2)0.10618 (2)0.02326 (11)0.0965 (17)
Cl20.23823 (5)0.48953 (3)0.32488 (2)0.02183 (13)0.3419 (18)
Cl30.62807 (6)0.34583 (3)0.32995 (3)0.02465 (15)0.5019 (19)
Cl40.53176 (7)0.53958 (4)0.17615 (3)0.02306 (17)0.6847 (19)
N10.8621 (3)0.47579 (17)0.09803 (18)0.0213 (6)
N20.4249 (3)0.11942 (17)0.06874 (17)0.0197 (6)
C10.9057 (6)0.7653 (3)0.1760 (3)0.0485 (12)
H1A0.97250.81340.17980.073*
H1B0.89310.75190.23110.073*
H1C0.80110.77580.13830.073*
C20.9844 (5)0.6951 (2)0.1432 (3)0.0393 (10)
H2A0.99440.70810.08690.047*
H2B1.09260.68660.17950.047*
C30.8885 (5)0.6192 (2)0.1401 (3)0.0326 (9)
H3A0.77860.62880.10620.039*
H3B0.88320.60490.19690.039*
C40.9603 (4)0.5501 (2)0.1036 (2)0.0264 (8)
H4A0.96890.56510.04750.032*
H4B1.06890.53930.13850.032*
C50.8900 (4)0.4246 (2)0.1624 (2)0.0227 (7)
H50.97110.43630.21130.027*
C60.8021 (4)0.3558 (2)0.1579 (2)0.0222 (7)
H60.82220.32020.20400.027*
C70.6840 (4)0.3373 (2)0.08722 (19)0.0186 (7)
C80.6557 (4)0.3926 (2)0.0221 (2)0.0237 (7)
H80.57490.38230.02720.028*
C90.7442 (4)0.4616 (2)0.0293 (2)0.0246 (7)
H90.72220.49990.01450.029*
C100.4928 (4)0.1502 (2)0.1435 (2)0.0222 (7)
H100.48180.12320.19190.027*
C110.5781 (4)0.2205 (2)0.1510 (2)0.0199 (7)
H110.62690.24160.20440.024*
C120.5935 (4)0.26102 (19)0.0800 (2)0.0180 (6)
C130.5245 (4)0.2266 (2)0.0037 (2)0.0209 (7)
H130.53540.25190.04560.025*
C140.4404 (4)0.1562 (2)0.0009 (2)0.0214 (7)
H140.39270.13300.05350.026*
C150.3217 (4)0.0467 (2)0.0626 (2)0.0266 (8)
H15A0.37770.00480.10150.032*
H15B0.29820.02460.00570.032*
C160.1663 (5)0.0697 (2)0.0838 (3)0.0317 (8)
H16A0.10110.02050.08240.038*
H16B0.19150.09120.14100.038*
C170.0703 (4)0.1309 (2)0.0261 (2)0.0313 (8)
H17A0.03970.10830.03070.038*
H17B0.13720.17900.02520.038*
C180.0791 (5)0.1565 (3)0.0506 (3)0.0444 (11)
H18A0.13750.19610.01070.067*
H18B0.04950.18050.10620.067*
H18C0.14670.10930.05090.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cd10.02436 (13)0.01957 (13)0.01644 (12)0.00087 (9)0.00734 (10)0.00126 (9)
Br10.0256 (2)0.0214 (2)0.02208 (19)0.00007 (14)0.00474 (15)0.00461 (14)
Br20.0222 (2)0.0263 (2)0.0179 (2)0.00361 (16)0.00688 (16)0.00281 (16)
Br30.0347 (3)0.0242 (3)0.0167 (2)0.0036 (2)0.0096 (2)0.00047 (19)
Br40.0288 (3)0.0255 (3)0.0168 (3)0.0041 (2)0.0094 (2)0.0004 (2)
Cl10.0256 (2)0.0214 (2)0.02208 (19)0.00007 (14)0.00474 (15)0.00461 (14)
Cl20.0222 (2)0.0263 (2)0.0179 (2)0.00361 (16)0.00688 (16)0.00281 (16)
Cl30.0347 (3)0.0242 (3)0.0167 (2)0.0036 (2)0.0096 (2)0.00047 (19)
Cl40.0288 (3)0.0255 (3)0.0168 (3)0.0041 (2)0.0094 (2)0.0004 (2)
N10.0219 (14)0.0195 (15)0.0245 (15)0.0002 (11)0.0099 (12)0.0017 (12)
N20.0199 (14)0.0162 (14)0.0226 (14)0.0030 (11)0.0050 (11)0.0009 (11)
C10.057 (3)0.028 (2)0.046 (3)0.004 (2)0.012 (2)0.006 (2)
C20.044 (2)0.030 (2)0.040 (2)0.0057 (19)0.004 (2)0.0020 (18)
C30.0293 (19)0.029 (2)0.042 (2)0.0049 (16)0.0124 (17)0.0086 (18)
C40.0270 (18)0.0233 (19)0.0318 (19)0.0068 (14)0.0126 (16)0.0020 (15)
C50.0216 (16)0.0253 (19)0.0212 (16)0.0018 (14)0.0059 (14)0.0021 (14)
C60.0228 (17)0.0250 (19)0.0195 (16)0.0005 (14)0.0071 (14)0.0011 (14)
C70.0197 (15)0.0200 (17)0.0174 (15)0.0032 (13)0.0073 (13)0.0009 (13)
C80.0242 (17)0.0265 (19)0.0207 (17)0.0025 (14)0.0061 (14)0.0018 (14)
C90.0270 (17)0.0252 (19)0.0230 (17)0.0011 (15)0.0092 (15)0.0020 (14)
C100.0277 (18)0.0211 (18)0.0177 (16)0.0030 (14)0.0053 (14)0.0024 (13)
C110.0211 (16)0.0210 (17)0.0173 (16)0.0030 (13)0.0047 (13)0.0007 (13)
C120.0183 (15)0.0171 (16)0.0196 (15)0.0055 (12)0.0067 (13)0.0004 (13)
C130.0207 (16)0.0243 (18)0.0190 (16)0.0008 (13)0.0077 (13)0.0010 (14)
C140.0221 (16)0.0233 (18)0.0186 (16)0.0010 (14)0.0048 (13)0.0043 (13)
C150.0301 (19)0.0168 (17)0.0313 (19)0.0029 (14)0.0048 (16)0.0018 (15)
C160.031 (2)0.028 (2)0.036 (2)0.0106 (16)0.0089 (17)0.0005 (17)
C170.0294 (19)0.028 (2)0.037 (2)0.0022 (16)0.0102 (17)0.0013 (17)
C180.028 (2)0.046 (3)0.062 (3)0.0073 (19)0.016 (2)0.006 (2)
Geometric parameters (Å, º) top
Cd1—Br42.5168 (6)C7—C81.394 (5)
Cd1—Br32.5665 (6)C7—C121.479 (5)
Cd1—Br12.5720 (4)C8—C91.369 (5)
Cd1—Br22.5901 (5)C8—H80.9500
N1—C51.342 (4)C9—H90.9500
N1—C91.348 (5)C10—C111.370 (5)
N1—C41.489 (4)C10—H100.9500
N2—C101.337 (4)C11—C121.398 (4)
N2—C141.350 (4)C11—H110.9500
N2—C151.492 (4)C12—C131.384 (5)
C1—C21.523 (6)C13—C141.371 (5)
C1—H1A0.9800C13—H130.9500
C1—H1B0.9800C14—H140.9500
C1—H1C0.9800C15—C161.531 (5)
C2—C31.505 (5)C15—H15A0.9900
C2—H2A0.9900C15—H15B0.9900
C2—H2B0.9900C16—C171.497 (5)
C3—C41.507 (5)C16—H16A0.9900
C3—H3A0.9900C16—H16B0.9900
C3—H3B0.9900C17—C181.521 (5)
C4—H4A0.9900C17—H17A0.9900
C4—H4B0.9900C17—H17B0.9900
C5—C61.366 (5)C18—H18A0.9800
C5—H50.9500C18—H18B0.9800
C6—C71.385 (5)C18—H18C0.9800
C6—H60.9500
Br4—Cd1—Br3106.22 (2)C9—C8—C7120.0 (3)
Br4—Cd1—Br1106.574 (18)C9—C8—H8120.0
Br3—Cd1—Br1119.113 (17)C7—C8—H8120.0
Br4—Cd1—Br2105.991 (18)N1—C9—C8120.5 (3)
Br3—Cd1—Br2106.390 (16)N1—C9—H9119.7
Br1—Cd1—Br2111.718 (15)C8—C9—H9119.7
C5—N1—C9120.8 (3)N2—C10—C11120.6 (3)
C5—N1—C4119.5 (3)N2—C10—H10119.7
C9—N1—C4119.7 (3)C11—C10—H10119.7
C10—N2—C14120.8 (3)C10—C11—C12120.0 (3)
C10—N2—C15119.2 (3)C10—C11—H11120.0
C14—N2—C15119.9 (3)C12—C11—H11120.0
C2—C1—H1A109.5C13—C12—C11117.8 (3)
C2—C1—H1B109.5C13—C12—C7121.6 (3)
H1A—C1—H1B109.5C11—C12—C7120.6 (3)
C2—C1—H1C109.5C14—C13—C12120.2 (3)
H1A—C1—H1C109.5C14—C13—H13119.9
H1B—C1—H1C109.5C12—C13—H13119.9
C3—C2—C1110.9 (4)N2—C14—C13120.5 (3)
C3—C2—H2A109.5N2—C14—H14119.8
C1—C2—H2A109.5C13—C14—H14119.8
C3—C2—H2B109.5N2—C15—C16109.5 (3)
C1—C2—H2B109.5N2—C15—H15A109.8
H2A—C2—H2B108.0C16—C15—H15A109.8
C2—C3—C4111.6 (3)N2—C15—H15B109.8
C2—C3—H3A109.3C16—C15—H15B109.8
C4—C3—H3A109.3H15A—C15—H15B108.2
C2—C3—H3B109.3C17—C16—C15113.5 (3)
C4—C3—H3B109.3C17—C16—H16A108.9
H3A—C3—H3B108.0C15—C16—H16A108.9
N1—C4—C3111.4 (3)C17—C16—H16B108.9
N1—C4—H4A109.3C15—C16—H16B108.9
C3—C4—H4A109.3H16A—C16—H16B107.7
N1—C4—H4B109.3C16—C17—C18112.9 (3)
C3—C4—H4B109.3C16—C17—H17A109.0
H4A—C4—H4B108.0C18—C17—H17A109.0
N1—C5—C6120.1 (3)C16—C17—H17B109.0
N1—C5—H5119.9C18—C17—H17B109.0
C6—C5—H5119.9H17A—C17—H17B107.8
C5—C6—C7121.0 (3)C17—C18—H18A109.5
C5—C6—H6119.5C17—C18—H18B109.5
C7—C6—H6119.5H18A—C18—H18B109.5
C6—C7—C8117.5 (3)C17—C18—H18C109.5
C6—C7—C12121.4 (3)H18A—C18—H18C109.5
C8—C7—C12121.1 (3)H18B—C18—H18C109.5
C1—C2—C3—C4177.1 (4)N2—C10—C11—C120.6 (5)
C5—N1—C4—C389.0 (4)C10—C11—C12—C131.9 (5)
C9—N1—C4—C389.4 (4)C10—C11—C12—C7179.4 (3)
C2—C3—C4—N1178.1 (3)C6—C7—C12—C13154.1 (3)
C9—N1—C5—C62.2 (5)C8—C7—C12—C1324.6 (4)
C4—N1—C5—C6179.4 (3)C6—C7—C12—C1124.5 (4)
N1—C5—C6—C70.4 (5)C8—C7—C12—C11156.8 (3)
C5—C6—C7—C81.8 (5)C11—C12—C13—C141.8 (5)
C5—C6—C7—C12176.9 (3)C7—C12—C13—C14179.5 (3)
C6—C7—C8—C90.7 (5)C10—N2—C14—C130.9 (5)
C12—C7—C8—C9178.1 (3)C15—N2—C14—C13174.8 (3)
C5—N1—C9—C83.4 (5)C12—C13—C14—N20.4 (5)
C4—N1—C9—C8178.2 (3)C10—N2—C15—C1670.9 (4)
C7—C8—C9—N11.9 (5)C14—N2—C15—C16104.9 (3)
C14—N2—C10—C110.8 (5)N2—C15—C16—C1761.5 (4)
C15—N2—C10—C11174.9 (3)C15—C16—C17—C18176.9 (3)

Experimental details

Crystal data
Chemical formula(C18H26N2)[CdBr2.375Cl1.625]
Mr630.20
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)8.6969 (5), 16.6024 (10), 16.6881 (10)
β (°) 104.936 (1)
V3)2328.2 (2)
Z4
Radiation typeMo Kα
µ (mm1)5.21
Crystal size (mm)0.30 × 0.30 × 0.10
Data collection
DiffractometerBruker SMART APEX
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.304, 0.624
No. of measured, independent and
observed [I > 2σ(I)] reflections
21634, 5354, 4487
Rint0.045
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.031, 0.078, 1.02
No. of reflections5354
No. of parameters234
No. of restraints5
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.49, 1.27

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

 

Acknowledgements

We thank the National Natural Science Foundation of China (Nos. J0830412, 20671083), Zhengzhou University and the University of Malaya for supporting this study.

References

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