metal-organic compounds
Bis(3-methylpyridinium) tetra(chlorido/bromido)cuprate(II)
aDepartment of Chemistry Education and Interdisciplinary Program of Advanced Information and Display Materials, Pusan National University, Pusan 609-735, Republic of Korea, and bDepartment of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
*Correspondence e-mail: skkang@cnu.ac.kr
The structure of the title salt, (C6H8N)2[CuCl3.4Br0.6], consists of two 3-methylpyridinium cations and a distorted tetrahedral [CuCl3.4Br0.6]2− dianion. Substitutional disorder with Br is exhibited for three of the Cl atoms of the anion, giving a mixed chloride/bromide cuprate(II) anion. In the crystal, intermolecular N—H⋯Cl hydrogen bonds link two cations to one anion, forming a three-ion aggregate. These are connected into a supramolecular chain along the b axis via π–π interactions between the pyridinium rings [centroid–centroid distance = 3.743 (3) Å].
Related literature
For general background to the geometry of the tetrahalidocuprate(II) species, see: Solomon et al. (1992); Kim et al. (2001); Panja et al. (2005); Sengottvelan et al. (2009). For its magnetic properties, see: Lee et al. (2004); Turnbull et al. (2005); Shapiro et al. (2007). CuBr42− ions usually show less distortion from the ideal tetrahedral geometry compared with CuCl42− ions, see: Edwards et al. (2011); AlDaman & Haddad (2011).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2002); cell SAINT (Bruker, 2002); 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 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536811019076/tk2745sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536811019076/tk2745Isup2.hkl
Copper(II) chloride (1.36 g, 8 mmol) dissolved in ethanol, was added drop wise to a stirred ethanolic solution containing 3-methylpyridine (0.744 g, 8 mmol) and concentrated HBr (0.5 ml, 4.4 mmol). The mixture was refluxed for approximately 4 h at 333 K. The resulting solution was filtered and allowed to stand at room temperature. The crystals were obtained after 2–3 days.
The H1 and H8 atoms were located in a difference map and refined freely. Other H atoms are positioned geometrically and refined using a riding model, with C—H = 0.93 – 096 Å, and with Uiso(H) = 1.2Ueq(C) for aromatic and 1.5Ueq(C) for methyl H atoms. Atoms Cl2, Cl3, and Cl4 are substitutionally disordered with Br atoms. The final occupancy factors for the Cl and Br atoms were fixed at 0.80 and 0.20, respectively.
Data collection: SMART (Bruker, 2002); cell
SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).(C6H8N)2[CuBr0.60Cl3.40] | F(000) = 839.2 |
Mr = 420.28 | Dx = 1.693 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 3355 reflections |
a = 9.0617 (18) Å | θ = 2.8–23.7° |
b = 13.259 (3) Å | µ = 3.32 mm−1 |
c = 14.060 (3) Å | T = 295 K |
β = 102.47 (3)° | Block, brown |
V = 1649.4 (6) Å3 | 0.19 × 0.15 × 0.15 mm |
Z = 4 |
Bruker SMART CCD area-detector diffractometer | 2621 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.039 |
ϕ and ω scans | θmax = 28.3°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | h = −10→12 |
Tmin = 0.560, Tmax = 0.610 | k = −17→17 |
17556 measured reflections | l = −18→18 |
4094 independent reflections |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.089 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0389P)2 + 0.0822P] where P = (Fo2 + 2Fc2)/3 |
4094 reflections | (Δ/σ)max = 0.001 |
209 parameters | Δρmax = 0.34 e Å−3 |
0 restraints | Δρmin = −0.41 e Å−3 |
(C6H8N)2[CuBr0.60Cl3.40] | V = 1649.4 (6) Å3 |
Mr = 420.28 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 9.0617 (18) Å | µ = 3.32 mm−1 |
b = 13.259 (3) Å | T = 295 K |
c = 14.060 (3) Å | 0.19 × 0.15 × 0.15 mm |
β = 102.47 (3)° |
Bruker SMART CCD area-detector diffractometer | 4094 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 2621 reflections with I > 2σ(I) |
Tmin = 0.560, Tmax = 0.610 | Rint = 0.039 |
17556 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.089 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.34 e Å−3 |
4094 reflections | Δρmin = −0.41 e Å−3 |
209 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 | Occ. (<1) | |
Cu1 | 0.55622 (4) | 0.54229 (2) | 0.70365 (2) | 0.04278 (13) | |
Cl2 | 0.3635 (8) | 0.6509 (5) | 0.6823 (4) | 0.0600 (16) | 0.8 |
Br2 | 0.3543 (11) | 0.6580 (8) | 0.6803 (5) | 0.0397 (14) | 0.2 |
Cl3 | 0.7542 (4) | 0.6516 (3) | 0.7331 (2) | 0.0967 (10) | 0.8 |
Br3 | 0.7538 (3) | 0.6533 (2) | 0.73299 (19) | 0.0289 (6) | 0.2 |
Cl4 | 0.4607 (10) | 0.4267 (9) | 0.7907 (6) | 0.0538 (15) | 0.8 |
Br4 | 0.4680 (16) | 0.4110 (15) | 0.7913 (9) | 0.0511 (18) | 0.2 |
Cl5 | 0.65337 (8) | 0.43724 (5) | 0.60629 (6) | 0.0550 (2) | |
N1 | 0.4441 (3) | 0.2452 (2) | 0.59512 (19) | 0.0492 (6) | |
H1 | 0.485 (3) | 0.291 (2) | 0.621 (2) | 0.044 (9)* | |
C2 | 0.4632 (3) | 0.2199 (2) | 0.5066 (2) | 0.0457 (7) | |
H2 | 0.5221 | 0.26 | 0.4752 | 0.055* | |
C3 | 0.3953 (3) | 0.1343 (2) | 0.4620 (2) | 0.0451 (7) | |
C4 | 0.3078 (3) | 0.0789 (2) | 0.5126 (2) | 0.0526 (8) | |
H4 | 0.2593 | 0.0211 | 0.4842 | 0.063* | |
C5 | 0.2909 (3) | 0.1070 (2) | 0.6036 (2) | 0.0565 (8) | |
H5 | 0.2323 | 0.0686 | 0.6367 | 0.068* | |
C6 | 0.3615 (3) | 0.1921 (2) | 0.6445 (2) | 0.0516 (7) | |
H6 | 0.3519 | 0.2128 | 0.7061 | 0.062* | |
C7 | 0.4157 (4) | 0.1058 (2) | 0.3622 (2) | 0.0674 (9) | |
H7A | 0.5116 | 0.1301 | 0.3534 | 0.101* | |
H7B | 0.3362 | 0.1354 | 0.3139 | 0.101* | |
H7C | 0.4122 | 0.0338 | 0.3556 | 0.101* | |
N8 | 0.8582 (3) | 0.61568 (19) | 0.52884 (19) | 0.0494 (6) | |
H8 | 0.820 (4) | 0.599 (3) | 0.574 (2) | 0.082 (12)* | |
C9 | 0.9467 (3) | 0.6976 (2) | 0.54021 (19) | 0.0461 (7) | |
H9 | 0.9599 | 0.735 | 0.5974 | 0.055* | |
C10 | 1.0178 (3) | 0.7265 (2) | 0.46804 (19) | 0.0446 (7) | |
C11 | 0.9936 (3) | 0.6688 (2) | 0.3849 (2) | 0.0522 (7) | |
H11 | 1.0407 | 0.6864 | 0.3347 | 0.063* | |
C12 | 0.9011 (4) | 0.5857 (2) | 0.3745 (2) | 0.0587 (8) | |
H12 | 0.885 | 0.5478 | 0.3176 | 0.07* | |
C13 | 0.8329 (3) | 0.5591 (2) | 0.4483 (2) | 0.0559 (8) | |
H13 | 0.7703 | 0.5028 | 0.4427 | 0.067* | |
C14 | 1.1163 (4) | 0.8186 (2) | 0.4800 (2) | 0.0691 (9) | |
H14A | 1.0553 | 0.877 | 0.4589 | 0.104* | |
H14B | 1.1911 | 0.8115 | 0.4414 | 0.104* | |
H14C | 1.1654 | 0.8262 | 0.5472 | 0.104* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0438 (2) | 0.0394 (2) | 0.0472 (2) | −0.00244 (15) | 0.01439 (16) | −0.00025 (15) |
Cl2 | 0.060 (2) | 0.051 (2) | 0.073 (3) | 0.0085 (14) | 0.0232 (16) | −0.0012 (14) |
Br2 | 0.046 (2) | 0.040 (2) | 0.036 (3) | 0.0049 (18) | 0.0167 (17) | 0.0047 (16) |
Cl3 | 0.097 (2) | 0.091 (2) | 0.104 (2) | −0.0196 (18) | 0.0272 (18) | −0.0123 (19) |
Br3 | 0.0263 (13) | 0.0305 (15) | 0.0315 (14) | −0.0156 (11) | 0.0099 (11) | −0.0118 (12) |
Cl4 | 0.0612 (13) | 0.041 (3) | 0.0660 (18) | 0.0059 (13) | 0.0280 (14) | 0.0153 (12) |
Br4 | 0.066 (3) | 0.036 (4) | 0.052 (2) | 0.000 (2) | 0.014 (2) | 0.0125 (17) |
Cl5 | 0.0605 (5) | 0.0437 (4) | 0.0693 (5) | −0.0081 (3) | 0.0328 (4) | −0.0127 (4) |
N1 | 0.0478 (15) | 0.0433 (15) | 0.0527 (16) | −0.0041 (13) | 0.0029 (12) | −0.0027 (13) |
C2 | 0.0449 (16) | 0.0437 (16) | 0.0494 (17) | −0.0037 (13) | 0.0120 (13) | 0.0060 (14) |
C3 | 0.0444 (16) | 0.0417 (16) | 0.0473 (16) | 0.0046 (13) | 0.0054 (13) | 0.0060 (13) |
C4 | 0.0505 (18) | 0.0368 (15) | 0.066 (2) | −0.0078 (13) | 0.0032 (15) | 0.0033 (14) |
C5 | 0.0518 (19) | 0.0563 (19) | 0.064 (2) | −0.0032 (15) | 0.0180 (16) | 0.0121 (16) |
C6 | 0.0502 (18) | 0.062 (2) | 0.0449 (17) | 0.0057 (15) | 0.0141 (14) | 0.0085 (15) |
C7 | 0.087 (3) | 0.060 (2) | 0.054 (2) | 0.0054 (18) | 0.0111 (18) | −0.0029 (16) |
N8 | 0.0457 (15) | 0.0545 (16) | 0.0509 (16) | 0.0018 (12) | 0.0167 (12) | 0.0088 (13) |
C9 | 0.0473 (17) | 0.0496 (17) | 0.0421 (16) | 0.0010 (14) | 0.0110 (13) | −0.0021 (13) |
C10 | 0.0412 (15) | 0.0520 (17) | 0.0415 (16) | 0.0037 (13) | 0.0110 (12) | 0.0065 (13) |
C11 | 0.0509 (18) | 0.064 (2) | 0.0436 (17) | 0.0096 (16) | 0.0136 (14) | 0.0052 (15) |
C12 | 0.067 (2) | 0.060 (2) | 0.0457 (17) | 0.0075 (17) | 0.0055 (16) | −0.0093 (15) |
C13 | 0.0502 (18) | 0.0478 (18) | 0.065 (2) | −0.0019 (14) | 0.0025 (16) | −0.0008 (16) |
C14 | 0.069 (2) | 0.070 (2) | 0.072 (2) | −0.0139 (18) | 0.0230 (18) | 0.0057 (18) |
Cu1—Cl2 | 2.232 (8) | C7—H7A | 0.96 |
Cu1—Cl4 | 2.248 (10) | C7—H7B | 0.96 |
Cu1—Cl5 | 2.2604 (8) | C7—H7C | 0.96 |
Cu1—Cl3 | 2.273 (3) | N8—C13 | 1.336 (4) |
Cu1—Br3 | 2.286 (2) | N8—C9 | 1.339 (4) |
Cu1—Br2 | 2.356 (12) | N8—H8 | 0.82 (3) |
Cu1—Br4 | 2.369 (17) | C9—C10 | 1.369 (3) |
N1—C6 | 1.328 (4) | C9—H9 | 0.93 |
N1—C2 | 1.336 (4) | C10—C11 | 1.374 (4) |
N1—H1 | 0.76 (3) | C10—C14 | 1.500 (4) |
C2—C3 | 1.376 (4) | C11—C12 | 1.373 (4) |
C2—H2 | 0.93 | C11—H11 | 0.93 |
C3—C4 | 1.385 (4) | C12—C13 | 1.363 (4) |
C3—C7 | 1.502 (4) | C12—H12 | 0.93 |
C4—C5 | 1.373 (4) | C13—H13 | 0.93 |
C4—H4 | 0.93 | C14—H14A | 0.96 |
C5—C6 | 1.362 (4) | C14—H14B | 0.96 |
C5—H5 | 0.93 | C14—H14C | 0.96 |
C6—H6 | 0.93 | ||
Cl2—Cu1—Cl4 | 97.5 (3) | C4—C5—H5 | 120.6 |
Cl2—Cu1—Cl5 | 135.34 (14) | N1—C6—C5 | 119.0 (3) |
Cl4—Cu1—Cl5 | 99.0 (3) | N1—C6—H6 | 120.5 |
Cl2—Cu1—Cl3 | 100.2 (2) | C5—C6—H6 | 120.5 |
Cl4—Cu1—Cl3 | 135.8 (2) | C3—C7—H7A | 109.5 |
Cl5—Cu1—Cl3 | 96.18 (8) | C3—C7—H7B | 109.5 |
Cl2—Cu1—Br3 | 99.70 (18) | H7A—C7—H7B | 109.5 |
Cl4—Cu1—Br3 | 136.0 (2) | C3—C7—H7C | 109.5 |
Cl5—Cu1—Br3 | 96.53 (7) | H7A—C7—H7C | 109.5 |
Cl3—Cu1—Br3 | 0.49 (16) | H7B—C7—H7C | 109.5 |
Cl2—Cu1—Br2 | 0.6 (3) | C13—N8—C9 | 123.1 (3) |
Cl4—Cu1—Br2 | 98.1 (3) | C13—N8—H8 | 119 (2) |
Cl5—Cu1—Br2 | 135.17 (16) | C9—N8—H8 | 117 (2) |
Cl3—Cu1—Br2 | 99.7 (2) | N8—C9—C10 | 120.3 (3) |
Br3—Cu1—Br2 | 99.2 (2) | N8—C9—H9 | 119.9 |
Cl2—Cu1—Br4 | 101.6 (5) | C10—C9—H9 | 119.9 |
Cl4—Cu1—Br4 | 4.5 (7) | C9—C10—C11 | 117.4 (3) |
Cl5—Cu1—Br4 | 94.7 (4) | C9—C10—C14 | 120.6 (3) |
Cl3—Cu1—Br4 | 135.7 (3) | C11—C10—C14 | 122.0 (3) |
Br3—Cu1—Br4 | 135.9 (3) | C12—C11—C10 | 121.2 (3) |
Br2—Cu1—Br4 | 102.2 (5) | C12—C11—H11 | 119.4 |
C6—N1—C2 | 123.7 (3) | C10—C11—H11 | 119.4 |
C6—N1—H1 | 116 (2) | C13—C12—C11 | 119.6 (3) |
C2—N1—H1 | 120 (2) | C13—C12—H12 | 120.2 |
N1—C2—C3 | 119.8 (3) | C11—C12—H12 | 120.2 |
N1—C2—H2 | 120.1 | N8—C13—C12 | 118.4 (3) |
C3—C2—H2 | 120.1 | N8—C13—H13 | 120.8 |
C2—C3—C4 | 116.9 (3) | C12—C13—H13 | 120.8 |
C2—C3—C7 | 120.0 (3) | C10—C14—H14A | 109.5 |
C4—C3—C7 | 123.1 (3) | C10—C14—H14B | 109.5 |
C5—C4—C3 | 121.7 (3) | H14A—C14—H14B | 109.5 |
C5—C4—H4 | 119.1 | C10—C14—H14C | 109.5 |
C3—C4—H4 | 119.1 | H14A—C14—H14C | 109.5 |
C6—C5—C4 | 118.8 (3) | H14B—C14—H14C | 109.5 |
C6—C5—H5 | 120.6 |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Cl5 | 0.76 (3) | 2.50 (3) | 3.158 (3) | 145 (3) |
N8—H8···Cl3 | 0.82 (3) | 2.53 (3) | 3.245 (4) | 147 (3) |
N8—H8···Cl5 | 0.82 (3) | 2.72 (3) | 3.332 (3) | 133 (3) |
Experimental details
Crystal data | |
Chemical formula | (C6H8N)2[CuBr0.60Cl3.40] |
Mr | 420.28 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 295 |
a, b, c (Å) | 9.0617 (18), 13.259 (3), 14.060 (3) |
β (°) | 102.47 (3) |
V (Å3) | 1649.4 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 3.32 |
Crystal size (mm) | 0.19 × 0.15 × 0.15 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.560, 0.610 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17556, 4094, 2621 |
Rint | 0.039 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.089, 1.03 |
No. of reflections | 4094 |
No. of parameters | 209 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.34, −0.41 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
Cu1—Cl2 | 2.232 (8) | Cu1—Cl5 | 2.2604 (8) |
Cu1—Cl4 | 2.248 (10) | Cu1—Cl3 | 2.273 (3) |
Cl2—Cu1—Cl4 | 97.5 (3) | Cl2—Cu1—Cl3 | 100.2 (2) |
Cl2—Cu1—Cl5 | 135.34 (14) | Cl4—Cu1—Cl3 | 135.8 (2) |
Cl4—Cu1—Cl5 | 99.0 (3) | Cl5—Cu1—Cl3 | 96.18 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···Cl5 | 0.76 (3) | 2.50 (3) | 3.158 (3) | 145 (3) |
N8—H8···Cl3 | 0.82 (3) | 2.53 (3) | 3.245 (4) | 147 (3) |
N8—H8···Cl5 | 0.82 (3) | 2.72 (3) | 3.332 (3) | 133 (3) |
Acknowledgements
This work was supported by a 2-Year Research Grant of Pusan National University.
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The structural properties of tetrahalocuprate(II) compounds have attracted continued interest as model compounds for biological process (Solomon et al., 1992; Kim et al., 2001; Panja et al., 2005) as well as magnetic functional materials (Lee et al., 2004; Turnbull et al., 2005; Shapiro et al., 2007). In a previous paper, we (Sengottvelan et al., 2009) reported the structure of bis(3-methylpyridinium)tetrachlorocuprate(II) and investigated packing interactions such as hydrogen bonding and π–π interactions. Because CuBr42- ions usually show less distortion from the ideal tetrahedral geometry compared with CuCl42- (Edwards et al., 2011; AlDaman & Haddad, 2011), the analogous chemistry with CuBr42- was investigated. Herein, we disclose the the crystal structure of the bis(3-methylpyridinium) salt of a mixed-tetrachlorido/bromido cuprate(II) ion, [CuCl3.4Br0.6]2-.
The structure of the title salt, [C6H8N]2[CuCl3.4Br0.6], consists of two 3-methylpyridinium cations and one distorted tetrahedral [CuCl3.4Br0.6] anion. There are substitutional disorder for three of the Cl atoms anion to make a mixed-halo cuprate (II) anion. The [CuCl3.4Br0.6]2- anion is has approximately D2d symmetry, with the distortion from the ideal tetrahedral partly arising as a result of three different hydrogen bonding interactions with two 3-methylpyridinium cations (Fig. 1). The range of Cl—Cu—Cl angles is 96.18 (8) – 135.8 (2) ° (Table 1). There are weak aromatic π-π interactions between pyridinium rings of the discrete tri-ion aggregates [centroid-centroid distance = 3.743 (3) Å], and these lead to a supramolecular chain along the b axis.