4,4′-Bipyridinium tetra­chloro­aurate(III) chloride

The reaction of gold(III) chloride and 4,4′-bipyridine yields the compound (C₁₀H₈N₂)[AuCl₃]₂, which is converted to the ionic title compound (C₁₀H₁₀N₂)[AuCl₄]Cl upon recrystallization from DMSO. The Au^III ion in the tetra­chloro­aurate anion exhibits a square-planar geometry; this anion is linked to the bipyridinium cation by an N—H...·Cl hydrogen bond to form chains which extend parallel to the b axis. The bipyridinium cation exhibits 2 symmetry, whereas the tetra­chloro­aurate anion shows 2/m symmetry, and the chloride anion is located on a position with 222 symmetry.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.022
• wR factor = 0.061
• Data-to-parameter ratio = 17.8

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.52
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.11 Ratio

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.522
            Tmax scaled      0.116 Tmin scaled      0.055

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2004); software used to prepare material for publication: SHELXL97.

4,4'-Bipyridinium tetrachloroaurate(III) chloride

Crystal data

(C10H10N2)[AuCl4]Cl	F(000) = 992
Mr = 532.42	Dx = 2.379 Mg m^−3
Orthorhombic, Ibam	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -I 2 2c	Cell parameters from 2759 reflections
a = 7.8216 (5) Å	θ = 3.0–28.3°
b = 12.9012 (9) Å	µ = 10.78 mm^−1
c = 14.732 (1) Å	T = 291 K
V = 1486.5 (2) Å^3	Block, yellow
Z = 4	0.32 × 0.20 × 0.20 mm

Data collection

Bruker APEX area-detector diffractometer	891 independent reflections
Radiation source: fine-focus sealed tube	794 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
φ and ω scans	θmax = 27.5°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −9→10
Tmin = 0.105, Tmax = 0.222	k = −15→16
4351 measured reflections	l = −19→16

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.061	H atoms treated by a mixture of independent and constrained refinement
S = 1.15	w = 1/[σ^2(Fo^2) + (0.0343P)^2 + 1.1366P] where P = (Fo^2 + 2Fc^2)/3
891 reflections	(Δ/σ)max = 0.001
50 parameters	Δρmax = 0.97 e Å^−3
1 restraint	Δρmin = −1.69 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Au1	0.5000	0.5000	0.5000	0.02877 (12)
Cl1	0.5000	0.5000	0.7500	0.0651 (9)
Cl2	0.3637 (2)	0.34371 (8)	0.5000	0.0395 (3)
Cl3	0.7566 (2)	0.41593 (8)	0.5000	0.0454 (3)
N1	0.5000	0.7322 (4)	0.7500	0.042 (1)
C1	0.5665 (5)	0.7823 (3)	0.8214 (3)	0.0421 (8)
C2	0.5674 (5)	0.8880 (2)	0.8233 (2)	0.0360 (7)
C3	0.5000	0.9428 (4)	0.7500	0.029 (1)
H1n	0.5000	0.6663 (9)	0.7500	0.07 (3)*
H1	0.6120	0.7449	0.8697	0.050*
H2	0.6125	0.9231	0.8730	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Au1	0.0325 (2)	0.0177 (2)	0.0361 (2)	0.0016 (1)	0.000	0.000
Cl1	0.093 (2)	0.0132 (11)	0.089 (2)	0.000	0.000	0.000
Cl2	0.0441 (6)	0.0220 (5)	0.0526 (7)	−0.0038 (5)	0.000	0.000
Cl3	0.0359 (6)	0.0296 (6)	0.0707 (8)	0.0074 (5)	0.000	0.000
N1	0.044 (3)	0.015 (3)	0.066 (4)	0.000	0.011 (2)	0.000
C1	0.047 (2)	0.026 (2)	0.054 (2)	0.003 (2)	0.004 (2)	0.011 (2)
C2	0.043 (2)	0.025 (2)	0.040 (2)	0.001 (1)	−0.003 (2)	0.004 (1)
C3	0.033 (3)	0.016 (3)	0.037 (3)	0.000	0.006 (2)	0.000

Geometric parameters (Å, º)

Au1—Cl2	2.281 (1)	C2—C3	1.394 (4)
Au1—Cl2^i	2.281 (1)	C3—C2^ii	1.394 (4)
Au1—Cl3	2.282 (1)	C3—C3^iii	1.48 (1)
Au1—Cl3^i	2.282 (1)	N1—H1n	0.85 (1)
N1—C1^ii	1.340 (5)	C1—H1	0.93
N1—C1	1.340 (5)	C2—H2	0.93
C1—C2	1.365 (5)
Cl2—Au1—Cl2^i	180	C2—C3—C2^ii	119.1 (5)
Cl2—Au1—Cl3	89.49 (4)	C2—C3—C3^iii	120.5 (2)
Cl2—Au1—Cl3^i	90.51 (4)	C2^ii—C3—C3^iii	120.5 (2)
Cl2^i—Au1—Cl3	90.51 (4)	C1^ii—N1—H1n	118.8 (3)
Cl2^i—Au1—Cl3^i	89.49 (4)	C1—N1—H1n	118.8 (3)
Cl3—Au1—Cl3^i	180	N1—C1—H1	120.0
C1^ii—N1—C1	122.3 (5)	C2—C1—H1	120.0
N1—C1—C2	120.0 (4)	C1—C2—H2	120.4
C1—C2—C3	119.3 (4)	C3—C2—H2	120.4
C1^ii—N1—C1—C2	0.3 (3)	C1—C2—C3—C2^ii	0.3 (3)
N1—C1—C2—C3	−0.6 (6)	C1—C2—C3—C3^iii	−179.7 (3)

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1, y, −z+3/2; (iii) −x+1, −y+2, z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1n···Cl1	0.85 (1)	2.15 (1)	2.995 (6)	180