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Acta Crystallogr Sect E Struct Rep Online. 2009 May 1; 65(Pt 5): m491–m492.
Published online 2009 April 8. doi:  10.1107/S1600536809012264
PMCID: PMC2977556

2-[3-(2-Pyrid­yl)pyrazin-2-yl]pyridinium tetra­chloridoaurate(III)

Abstract

In the anion of the title compound, (C14H11N4)[AuCl4], the AuIII atom has an almost perfect square-planar coordination. In the crystal structure, an intra­molecular N—H(...)N and intermolecular C—H(...)Cl hydrogen bonds are observed. In addition, there is also a ring–metal inter­action between the pyrazine ring and the AuIII atom; the distance between the centroid of the pyrazine ring and the AuIII atom is 3.628 (2) Å.

Related literature

For proton-transfer systems involving [AuCl4], see: Calleja et al. (2001 [triangle]); Hasan et al. (1999 [triangle]); Hojjat Kashani et al. (2008 [triangle]); Johnson & Steed (1998 [triangle]); Safari et al. (2009 [triangle]); Yap et al. (1995 [triangle]); Zhang et al. (2006 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-0m491-scheme1.jpg

Experimental

Crystal data

  • (C14H11N4)[AuCl4]
  • M r = 574.04
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-0m491-efi1.jpg
  • a = 7.4098 (6) Å
  • b = 15.5188 (13) Å
  • c = 14.6197 (12) Å
  • β = 90.380 (1)°
  • V = 1681.1 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 9.39 mm−1
  • T = 150 K
  • 0.19 × 0.14 × 0.09 mm

Data collection

  • Bruker APEXII CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003 [triangle]) T min = 0.238, T max = 0.430
  • 19688 measured reflections
  • 5261 independent reflections
  • 4363 reflections with I > 2σ(I)
  • R int = 0.034

Refinement

  • R[F 2 > 2σ(F 2)] = 0.024
  • wR(F 2) = 0.052
  • S = 0.98
  • 5261 reflections
  • 208 parameters
  • H-atom parameters constrained
  • Δρmax = 1.19 e Å−3
  • Δρmin = −0.59 e Å−3

Data collection: APEX2 (Bruker, 2005 [triangle]); cell refinement: SAINT (Bruker, 2005 [triangle]); data reduction: SAINT; program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Selected geometric parameters (Å, °)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809012264/is2406sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809012264/is2406Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

NS and VA are grateful to Shahid Beheshti University for financial support.

supplementary crystallographic information

Comment

There are several proton transfer systems using HAuCl4 with proton acceptor molecules, such as [EMI][AuCl4] and [BMI]2[AuCl4].2H2O (Hasan et al., 1999), [H2bipy][AuCl4][Cl] (Zhang et al., 2006), [H7O3][15-crown-5][AuCl4] and [H5O2][benzo-15-crown-5]2[AuCl4] (Johnson & Steed, 1998), [H5O2]2[12-crown-4]2[AuCl4]2, [H3O][18-crown-6][AuCl4] and [H3O][4-nitrobenzo-18-crown-6][AuCl4] (Calleja et al., 2001), [DPpy.H][AuCl4] (Yap et al., 1995), [H2DA18C6][AuCl4].2H2O (Hojjat Kashani et al., 2008) and [dafonium][dafone][AuCl4] (Safari et al., 2009), where EMI is 1-ethyl-3-methylimidazolium, BMI is 1-butyl-3-methylimidazolium, H2bipy is 2, 2'-bipyridinium, DPpy.H is 2,6-diphenylpyridinium, H2DA18C6 is 1,10-diazonia-18-crown-6, dafonium is 9-oxo-4,5-diazafluoren-4-ium and dafone is 4,5-diazafluoren-9-one, have been synthesized and characterized by single-crystal X-ray diffraction methods. We report herein the synthesis and crystal structure of the title compound.

In the anion of the title compound (Fig. 1), the AuIII ion has a square-planar coordination. In the anion, the Au—Cl bond lengths and angles (Table 1) are within normal ranges.

In the crystal structure, inter- and intramolecular C—H···Cl hydrogen bonding interactions (Table 2) link the molecules. Furthermore, it is also observed a ring-metal interaction between the centroid of the pyrazine ring (N1/N2/C1–C4) and the atom Au1 (5/2 - x, -1/2 + y, 1/2 - z) with a distance of 3.628 (2) Å. The packing and the hydrogen bonding interactions of (I) down the a, b and c-axes are given in Figures 2, 3 and 4, respectively.

Experimental

For the preparation of the title compound, a solution of 2,3-bis(2-pyridyl)pyrazine (0.13 g, 0.55 mmol) in acetonitrile (10 ml) was added to a solution of HAuCl4.3H2O, (0.21 g, 0.55 mmol) in ethanol (5 ml) and the resulting yellow solution was stirred for 15 min at 313 K. This solution was left to evaporate slowly at room temperature. After one week, yellow block crystals of the title compound were isolated (yield 0.23 g, 72.8%; m.p. 419 K).

Refinement

All H atoms were found in a difference Fourier map. H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 Å and N—H = 0.86 Å, and with Uiso(H) = 1.2Ueq(C or N). The highest residual peak is located 0.79 Å from atom Au1 and the deepest hole is located 1.55 Å from atom Au1.

Figures

Fig. 1.
ORTEP drawing of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.
Fig. 2.
The packing and hydrogen bonding interactions of the title compound, viewed down a-axis.
Fig. 3.
The packing and hydrogen bonding interactions of the title compound, viewed down b-axis.
Fig. 4.
The packing and hydrogen bonding interactions of the title compound, viewed down c-axis.

Crystal data

(C14H11N4)[AuCl4]F(000) = 1080
Mr = 574.04Dx = 2.268 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 6388 reflections
a = 7.4098 (6) Åθ = 2.6–30.4°
b = 15.5188 (13) ŵ = 9.39 mm1
c = 14.6197 (12) ÅT = 150 K
β = 90.380 (1)°Block, yellow
V = 1681.1 (2) Å30.19 × 0.14 × 0.09 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer5261 independent reflections
Radiation source: sealed tube4363 reflections with I > 2σ(I)
graphiteRint = 0.034
[var phi] and ω scansθmax = 31.0°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)h = −10→10
Tmin = 0.238, Tmax = 0.430k = −22→21
19688 measured reflectionsl = −21→20

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.024Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.052H-atom parameters constrained
S = 0.98w = 1/[σ2(Fo2) + (0.025P)2], where P = (Fo2 + 2Fc2)/3
5261 reflections(Δ/σ)max = 0.001
208 parametersΔρmax = 1.19 e Å3
0 restraintsΔρmin = −0.59 e Å3

Special details

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles
Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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)

xyzUiso*/Ueq
N11.1698 (4)−0.52205 (18)0.12698 (19)0.0357 (8)
N21.1649 (4)−0.54680 (16)0.3126 (2)0.0360 (9)
N31.0216 (3)−0.30683 (16)0.16412 (16)0.0294 (8)
N41.0255 (3)−0.32719 (16)0.33648 (16)0.0282 (7)
C11.2037 (5)−0.5982 (2)0.1627 (3)0.0409 (11)
C21.1997 (5)−0.6103 (2)0.2554 (3)0.0431 (13)
C31.1299 (4)−0.4683 (2)0.2781 (2)0.0296 (9)
C41.1307 (4)−0.45514 (18)0.1822 (2)0.0268 (8)
C51.0952 (4)−0.37680 (19)0.1264 (2)0.0260 (8)
C61.1306 (4)−0.3760 (2)0.0328 (2)0.0334 (9)
C71.0901 (4)−0.3036 (2)−0.0181 (2)0.0392 (10)
C81.0152 (4)−0.2326 (2)0.0230 (2)0.0374 (10)
C90.9807 (4)−0.2366 (2)0.1154 (2)0.0334 (9)
C101.0970 (4)−0.40505 (19)0.3547 (2)0.0280 (8)
C111.1365 (4)−0.4282 (2)0.4450 (2)0.0330 (10)
C121.0989 (4)−0.3714 (2)0.5152 (2)0.0361 (10)
C131.0247 (4)−0.2920 (2)0.4954 (2)0.0355 (10)
C140.9907 (4)−0.2725 (2)0.4046 (2)0.0332 (9)
Au10.88109 (1)0.05497 (1)0.26548 (1)0.0239 (1)
Cl10.97121 (13)0.19452 (5)0.24868 (6)0.0427 (3)
Cl20.86854 (13)0.07321 (6)0.41954 (5)0.0401 (3)
Cl30.78564 (11)−0.08392 (5)0.28205 (5)0.0346 (2)
Cl40.89453 (13)0.03479 (6)0.11117 (5)0.0418 (3)
H11.23080−0.644300.124500.0490*
H21.22220−0.665000.278800.0520*
H30.99980−0.307000.221800.0350*
H61.18110−0.424000.004800.0400*
H71.11370−0.30280−0.080500.0470*
H80.98850−0.18330−0.010600.0450*
H90.92800−0.189600.144300.0400*
H111.18790−0.481600.457800.0400*
H121.12350−0.386700.575500.0430*
H130.99840−0.252800.541600.0430*
H140.94140−0.219000.390400.0400*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
N10.0365 (15)0.0331 (14)0.0375 (15)0.0023 (12)0.0026 (12)−0.0081 (12)
N20.0393 (15)0.0238 (14)0.0446 (17)0.0003 (11)−0.0106 (13)0.0026 (11)
N30.0322 (13)0.0321 (14)0.0240 (12)0.0022 (11)0.0001 (10)0.0000 (10)
N40.0301 (13)0.0277 (13)0.0268 (12)0.0001 (10)0.0003 (10)0.0021 (10)
C10.0405 (19)0.0322 (18)0.050 (2)0.0046 (15)0.0005 (16)−0.0094 (15)
C20.0360 (18)0.0280 (17)0.065 (3)0.0023 (14)−0.0124 (17)−0.0007 (16)
C30.0251 (14)0.0253 (14)0.0384 (18)−0.0014 (11)−0.0038 (12)0.0010 (13)
C40.0231 (14)0.0268 (15)0.0304 (15)−0.0001 (11)0.0011 (11)−0.0020 (12)
C50.0232 (13)0.0288 (15)0.0260 (14)−0.0025 (11)−0.0014 (11)−0.0032 (12)
C60.0336 (16)0.0368 (17)0.0299 (16)0.0024 (13)0.0043 (13)−0.0030 (13)
C70.0327 (17)0.055 (2)0.0298 (16)−0.0009 (15)0.0047 (13)0.0038 (15)
C80.0367 (17)0.0423 (19)0.0333 (17)0.0008 (15)0.0012 (13)0.0121 (14)
C90.0399 (17)0.0312 (16)0.0289 (15)0.0063 (13)−0.0030 (13)0.0006 (12)
C100.0272 (14)0.0268 (15)0.0300 (15)−0.0050 (12)0.0001 (12)0.0030 (12)
C110.0303 (16)0.0327 (17)0.0359 (17)−0.0044 (12)−0.0045 (13)0.0061 (13)
C120.0411 (18)0.0435 (19)0.0236 (15)−0.0077 (15)−0.0049 (13)0.0024 (13)
C130.0385 (17)0.0395 (18)0.0286 (16)−0.0011 (14)−0.0004 (13)−0.0044 (14)
C140.0368 (17)0.0331 (16)0.0296 (16)0.0038 (13)0.0032 (13)0.0025 (13)
Au10.0246 (1)0.0239 (1)0.0232 (1)0.0008 (1)−0.0003 (1)0.0022 (1)
Cl10.0579 (5)0.0295 (4)0.0407 (4)−0.0118 (4)−0.0047 (4)0.0055 (3)
Cl20.0549 (5)0.0410 (4)0.0245 (4)−0.0015 (4)0.0016 (3)−0.0010 (3)
Cl30.0420 (4)0.0243 (3)0.0376 (4)−0.0005 (3)0.0064 (3)0.0020 (3)
Cl40.0535 (5)0.0485 (5)0.0235 (4)−0.0127 (4)0.0017 (3)−0.0010 (3)

Geometric parameters (Å, °)

Au1—Cl12.2801 (8)C6—C71.380 (4)
Au1—Cl22.2725 (8)C7—C81.374 (4)
Au1—Cl32.2818 (8)C8—C91.378 (4)
Au1—Cl42.2805 (8)C10—C111.397 (4)
N1—C41.348 (4)C11—C121.383 (4)
N1—C11.316 (4)C12—C131.379 (4)
N2—C21.319 (5)C13—C141.383 (4)
N2—C31.343 (4)C1—H10.9300
N3—C91.336 (4)C2—H20.9300
N3—C51.336 (4)C6—H60.9300
N4—C141.335 (4)C7—H70.9300
N4—C101.345 (4)C8—H80.9300
N3—H30.8600C9—H90.9300
C1—C21.369 (6)C11—H110.9300
C3—C101.510 (4)C12—H120.9300
C3—C41.417 (4)C13—H130.9300
C4—C51.487 (4)C14—H140.9300
C5—C61.395 (4)
Cl1···Cl43.2394 (12)C10···N33.222 (4)
Cl1···C2i3.471 (3)C11···Cl4xiv3.497 (3)
Cl1···Cl23.2230 (12)C11···C11ix3.419 (4)
Cl2···Cl33.2167 (12)C11···Cl4xii3.622 (3)
Cl2···Cl13.2230 (12)C12···N2ix3.440 (4)
Cl2···N1ii3.472 (3)C12···C8xiv3.483 (4)
Cl2···C5iii3.582 (3)C12···C9xiv3.592 (4)
Cl3···Cl23.2167 (12)C12···Cl4xiv3.627 (3)
Cl3···Cl43.2113 (11)C13···C7ii3.550 (4)
Cl4···Cl13.2394 (12)C14···C7ii3.395 (4)
Cl4···C11iv3.622 (3)C1···H7x3.0500
Cl4···C12v3.627 (3)C3···H32.8000
Cl4···C11v3.497 (3)C7···H1x2.9500
Cl4···Cl33.2113 (11)C7···H14viii2.9600
Cl1···H2i2.9000C9···H2iv2.9000
Cl1···H7vi3.0400C10···H32.5700
Cl2···H6ii2.9800C12···H8xiv3.0400
Cl2···H13vii3.0100C14···H32.7300
Cl3···H7ii2.9600C14···H1iv2.9000
Cl3···H142.8700C14···H7ii3.0400
Cl3···H92.8100H1···C14xii2.9000
Cl4···H8vi2.8700H1···C7x2.9500
Cl4···H12v3.0900H2···C9xii2.9000
Cl4···H11v2.8300H2···Cl1xi2.9000
N1···N22.741 (4)H3···C32.8000
N1···Cl2viii3.472 (3)H3···C102.5700
N2···C12ix3.440 (4)H3···N41.7100
N2···N12.741 (4)H3···C142.7300
N3···C103.222 (4)H6···N12.3500
N3···N42.540 (3)H6···Cl2viii2.9800
N4···N32.540 (3)H7···Cl1vi3.0400
N4···C53.212 (4)H7···C1x3.0500
N1···H62.3500H7···Cl3viii2.9600
N2···H112.3600H7···C14viii3.0400
N2···H12ix2.8900H7···H14viii2.4900
N4···H31.7100H8···Cl4vi2.8700
C1···C7x3.387 (5)H8···C12v3.0400
C2···Cl1xi3.471 (3)H9···Cl32.8100
C2···C9xii3.600 (5)H11···N22.3600
C5···N43.212 (4)H11···Cl4xiv2.8300
C5···Cl2xiii3.582 (3)H12···Cl4xiv3.0900
C7···C14viii3.395 (4)H12···N2ix2.8900
C7···C1x3.387 (5)H13···Cl2vii3.0100
C7···C13viii3.550 (4)H14···H7ii2.4900
C8···C12v3.483 (4)H14···Cl32.8700
C9···C2iv3.600 (5)H14···C7ii2.9600
C9···C12v3.592 (4)
Cl3—Au1—Cl489.48 (3)C3—C10—C11120.0 (3)
Cl1—Au1—Cl490.52 (3)N4—C10—C3120.2 (3)
Cl1—Au1—Cl290.14 (3)N4—C10—C11119.9 (3)
Cl1—Au1—Cl3178.97 (3)C10—C11—C12119.7 (3)
Cl2—Au1—Cl389.87 (3)C11—C12—C13119.7 (3)
Cl2—Au1—Cl4179.25 (3)C12—C13—C14117.8 (3)
C1—N1—C4119.7 (3)N4—C14—C13122.8 (3)
C2—N2—C3118.5 (3)N1—C1—H1120.00
C5—N3—C9122.3 (3)C2—C1—H1120.00
C10—N4—C14120.1 (2)C1—C2—H2119.00
C9—N3—H3119.00N2—C2—H2119.00
C5—N3—H3119.00C5—C6—H6120.00
N1—C1—C2120.7 (3)C7—C6—H6120.00
N2—C2—C1122.1 (3)C6—C7—H7120.00
C4—C3—C10129.9 (3)C8—C7—H7120.00
N2—C3—C4120.0 (3)C9—C8—H8121.00
N2—C3—C10110.1 (3)C7—C8—H8121.00
N1—C4—C5109.8 (3)N3—C9—H9119.00
N1—C4—C3118.9 (3)C8—C9—H9119.00
C3—C4—C5131.2 (3)C10—C11—H11120.00
C4—C5—C6120.8 (3)C12—C11—H11120.00
N3—C5—C6118.5 (3)C13—C12—H12120.00
N3—C5—C4120.6 (3)C11—C12—H12120.00
C5—C6—C7119.7 (3)C12—C13—H13121.00
C6—C7—C8120.3 (3)C14—C13—H13121.00
C7—C8—C9118.1 (3)C13—C14—H14119.00
N3—C9—C8121.1 (3)N4—C14—H14119.00
C4—N1—C1—C20.0 (5)N2—C3—C10—C1111.3 (4)
C1—N1—C4—C31.0 (5)C4—C3—C10—N414.0 (5)
C1—N1—C4—C5−179.2 (3)C4—C3—C10—C11−167.7 (3)
C3—N2—C2—C11.0 (5)N1—C4—C5—N3167.6 (3)
C2—N2—C3—C40.1 (5)N1—C4—C5—C6−9.6 (4)
C2—N2—C3—C10−179.1 (3)C3—C4—C5—N3−12.7 (5)
C9—N3—C5—C4−177.1 (3)C3—C4—C5—C6170.2 (3)
C9—N3—C5—C60.1 (4)N3—C5—C6—C70.3 (4)
C5—N3—C9—C8−0.9 (4)C4—C5—C6—C7177.6 (3)
C14—N4—C10—C3177.7 (3)C5—C6—C7—C80.0 (4)
C14—N4—C10—C11−0.7 (4)C6—C7—C8—C9−0.7 (4)
C10—N4—C14—C13−0.1 (4)C7—C8—C9—N31.1 (4)
N1—C1—C2—N2−1.1 (6)N4—C10—C11—C121.1 (4)
N2—C3—C4—N1−1.1 (4)C3—C10—C11—C12−177.3 (3)
N2—C3—C4—C5179.2 (3)C10—C11—C12—C13−0.8 (4)
C10—C3—C4—N1177.9 (3)C11—C12—C13—C140.0 (4)
C10—C3—C4—C5−1.9 (5)C12—C13—C14—N40.5 (5)
N2—C3—C10—N4−167.1 (3)

Symmetry codes: (i) x, y+1, z; (ii) x−1/2, −y−1/2, z+1/2; (iii) −x+3/2, y+1/2, −z+1/2; (iv) −x+5/2, y+1/2, −z+1/2; (v) x−1/2, −y−1/2, z−1/2; (vi) −x+2, −y, −z; (vii) −x+2, −y, −z+1; (viii) x+1/2, −y−1/2, z−1/2; (ix) −x+2, −y−1, −z+1; (x) −x+2, −y−1, −z; (xi) x, y−1, z; (xii) −x+5/2, y−1/2, −z+1/2; (xiii) −x+3/2, y−1/2, −z+1/2; (xiv) x+1/2, −y−1/2, z+1/2.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N3—H3···N40.861.712.540 (3)160
C6—H6···N10.932.352.667 (4)100
C9—H9···Cl30.932.813.699 (3)161
C11—H11···N20.932.362.680 (4)100
C11—H11···Cl4xiv0.932.833.497 (3)130

Symmetry codes: (xiv) x+1/2, −y−1/2, z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2406).

References

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