Redetermination of 2,2'-bipyridine-1,1'-diium dibromide.

In the title mol-ecular salt, C(10)H(10)N(2) (2+)·2Br(-), the dihedral angle between the aromatic rings is 20.83 (14)° and the N-H groups have a transoid conformaton [N-C-C-N = 158.5 (3)°]. In the crystal, the cations are linked to the anions by two N-H⋯Br and five C-H⋯Br hydrogen bonds, generating corrugated sheets incorporating R(2) (1)(7), R(4) (2)(10), R(4) (2)(11) and two different R(4) (2)(12) loops. This structure was originally reported by Nakatsu et al. [Acta Cryst (1972), A28, S24], but no atomic coordinates are available.

Related literature

For the previous report of this structure as a conference abstract, see: Nakatsu et al. (1972 ▶). For related structures of 2,2′-bipyridium dication salts, see: Ma et al. (2000 ▶). For structures containing dicationic 2,2′-bipyridyl derivative n class="Chemical">salts, see: Amarante et al. (2011 ▶); Eckensberger et al. (2008 ▶). For structures of monocationic 2,2′-bipyridinium salts, see: Kavitha et al. (2006 ▶). For ring motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C10H10N2 2+·2Br−

M = 318.00

Monoclinic,

a = 7.5568 (6) Å

b = 9.7747 (7) Å

c = 15.3533 (12) Å

β = 95.830 (7)°

V = 1128.21 (15) Å3

Z = 4

Mo Kα radiation

μ = 7.15 mm−1

T = 293 K

0.20 × 0.15 × 0.10 mm

Data collection

Agilent Xcalibur EOS diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ▶) T min = 0.287, T max = 0.489

5425 measured reflections

3054 independent reflections

1884 reflections with I > 2σ(I)

R int = 0.032

Refinement

R[F 2 > 2σ(F 2)] = 0.037

wR(F 2) = 0.073

S = 1.03

3054 reflections

127 parameters

H-atom parameters constrained

Δρmax = 0.50 e Å−3

Δρmin = −0.57 e Å−3

Data collection: CrysAlis PRO (Agilent, 2011 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812040214/hb6957sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812040214/hb6957Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536812040214/hb6957Isup3.cml

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

C10H10N22+·2Br−	F(000) = 616
Mr = 318.00	Dx = 1.872 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 1832 reflections
a = 7.5568 (6) Å	θ = 2.9–29.1°
b = 9.7747 (7) Å	µ = 7.15 mm−1
c = 15.3533 (12) Å	T = 293 K
β = 95.830 (7)°	Chunk, colourless
V = 1128.21 (15) Å3	0.20 × 0.15 × 0.10 mm
Z = 4

Agilent Xcalibur EOS diffractometer	3054 independent reflections
Radiation source: Enhance (Mo) x-ray source	1884 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
Detector resolution: 16.0534 pixels mm-1	θmax = 29.2°, θmin = 3.4°
ω scans	h = −7→10
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −13→10
Tmin = 0.287, Tmax = 0.489	l = −21→16
5425 measured 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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.073	H-atom parameters constrained
S = 1.03	w = 1/[σ2(Fo2) + (0.025P)2] where P = (Fo2 + 2Fc2)/3
3054 reflections	(Δ/σ)max = 0.001
127 parameters	Δρmax = 0.50 e Å−3
0 restraints	Δρmin = −0.57 e Å−3

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
Br1	0.23397 (5)	0.03486 (4)	0.67326 (2)	0.04534 (13)
N1	0.4480 (4)	0.4858 (3)	0.63133 (16)	0.0384 (7)
H1A	0.5366	0.4580	0.6051	0.046*
C1	0.3257 (6)	0.3947 (4)	0.6491 (2)	0.0507 (10)
H1B	0.3369	0.3036	0.6330	0.061*
N2	0.5392 (4)	0.8449 (3)	0.61771 (15)	0.0369 (7)
H2A	0.4378	0.8714	0.6323	0.044*
C2	0.1841 (6)	0.4356 (4)	0.6909 (2)	0.0554 (11)
H2B	0.0950	0.3739	0.7013	0.066*
Br2	0.74405 (5)	0.29766 (4)	0.55966 (2)	0.04749 (13)
C3	0.1749 (5)	0.5695 (4)	0.7175 (2)	0.0532 (11)
H3A	0.0822	0.5979	0.7488	0.064*
C4	0.3033 (5)	0.6619 (4)	0.6978 (2)	0.0429 (9)
H4A	0.2968	0.7526	0.7154	0.051*
C5	0.4402 (4)	0.6197 (3)	0.65239 (19)	0.0314 (7)
C6	0.6477 (5)	0.9395 (4)	0.5912 (2)	0.0446 (9)
H6A	0.6141	1.0311	0.5898	0.054*
C7	0.8083 (6)	0.9019 (4)	0.5662 (2)	0.0505 (10)
H7A	0.8851	0.9671	0.5470	0.061*
C8	0.8553 (5)	0.7657 (4)	0.5698 (2)	0.0509 (10)
H8A	0.9641	0.7383	0.5524	0.061*
C9	0.7398 (5)	0.6683 (4)	0.5997 (2)	0.0449 (9)
H9A	0.7723	0.5765	0.6035	0.054*
C10	0.5767 (4)	0.7105 (3)	0.62330 (19)	0.0324 (8)

	U11	U22	U33	U12	U13	U23
Br1	0.0395 (2)	0.0378 (2)	0.0598 (2)	0.00431 (18)	0.01032 (17)	−0.00318 (18)
N1	0.0397 (19)	0.0320 (17)	0.0441 (16)	−0.0004 (14)	0.0068 (13)	0.0021 (13)
C1	0.058 (3)	0.035 (2)	0.058 (2)	−0.013 (2)	0.001 (2)	0.0056 (18)
N2	0.0309 (17)	0.0316 (17)	0.0483 (17)	−0.0033 (14)	0.0055 (13)	0.0014 (13)
C2	0.043 (3)	0.056 (3)	0.067 (3)	−0.019 (2)	0.008 (2)	0.016 (2)
Br2	0.0500 (3)	0.0356 (2)	0.0580 (2)	0.00351 (19)	0.01070 (18)	−0.00453 (16)
C3	0.036 (2)	0.060 (3)	0.067 (2)	0.004 (2)	0.0223 (19)	0.018 (2)
C4	0.037 (2)	0.036 (2)	0.057 (2)	0.0052 (17)	0.0111 (18)	0.0031 (17)
C5	0.0301 (19)	0.0260 (18)	0.0379 (17)	−0.0007 (16)	0.0022 (14)	0.0036 (14)
C6	0.045 (3)	0.037 (2)	0.052 (2)	−0.0067 (19)	0.0020 (18)	0.0054 (17)
C7	0.048 (3)	0.052 (3)	0.053 (2)	−0.015 (2)	0.0113 (19)	0.0052 (19)
C8	0.034 (2)	0.065 (3)	0.056 (2)	−0.005 (2)	0.0157 (17)	−0.002 (2)
C9	0.038 (2)	0.038 (2)	0.060 (2)	0.0053 (18)	0.0112 (18)	0.0026 (17)
C10	0.0304 (19)	0.0319 (19)	0.0349 (17)	0.0001 (16)	0.0033 (14)	0.0023 (14)

N1—C1	1.331 (4)	C4—C5	1.369 (4)
N1—C5	1.351 (4)	C4—H4A	0.9300
N1—H1A	0.8600	C5—C10	1.464 (4)
C1—C2	1.363 (6)	C6—C7	1.360 (5)
C1—H1B	0.9300	C6—H6A	0.9300
N2—C6	1.326 (4)	C7—C8	1.378 (5)
N2—C10	1.345 (4)	C7—H7A	0.9300
N2—H2A	0.8600	C8—C9	1.399 (5)
C2—C3	1.375 (5)	C8—H8A	0.9300
C2—H2B	0.9300	C9—C10	1.383 (5)
C3—C4	1.382 (5)	C9—H9A	0.9300
C3—H3A	0.9300
C1—N1—C5	123.5 (3)	N1—C5—C4	117.8 (3)
C1—N1—H1A	118.3	N1—C5—C10	117.7 (3)
C5—N1—H1A	118.3	C4—C5—C10	124.4 (3)
N1—C1—C2	119.6 (4)	N2—C6—C7	119.7 (4)
N1—C1—H1B	120.2	N2—C6—H6A	120.1
C2—C1—H1B	120.2	C7—C6—H6A	120.1
C6—N2—C10	124.6 (3)	C6—C7—C8	118.9 (4)
C6—N2—H2A	117.7	C6—C7—H7A	120.6
C10—N2—H2A	117.7	C8—C7—H7A	120.6
C1—C2—C3	119.0 (4)	C7—C8—C9	120.3 (4)
C1—C2—H2B	120.5	C7—C8—H8A	119.9
C3—C2—H2B	120.5	C9—C8—H8A	119.9
C2—C3—C4	119.9 (4)	C10—C9—C8	119.0 (3)
C2—C3—H3A	120.0	C10—C9—H9A	120.5
C4—C3—H3A	120.0	C8—C9—H9A	120.5
C5—C4—C3	120.0 (3)	N2—C10—C9	117.6 (3)
C5—C4—H4A	120.0	N2—C10—C5	117.5 (3)
C3—C4—H4A	120.0	C9—C10—C5	125.0 (3)
C5—N1—C1—C2	−0.2 (5)	C6—C7—C8—C9	−0.7 (5)
N1—C1—C2—C3	−2.9 (6)	C7—C8—C9—C10	1.6 (5)
C1—C2—C3—C4	3.3 (6)	C6—N2—C10—C9	−0.1 (5)
C2—C3—C4—C5	−0.5 (5)	C6—N2—C10—C5	−178.9 (3)
C1—N1—C5—C4	3.0 (5)	C8—C9—C10—N2	−1.2 (5)
C1—N1—C5—C10	−175.6 (3)	C8—C9—C10—C5	177.6 (3)
C3—C4—C5—N1	−2.6 (5)	N1—C5—C10—N2	158.5 (3)
C3—C4—C5—C10	175.9 (3)	C4—C5—C10—N2	−20.1 (5)
C10—N2—C6—C7	1.0 (5)	N1—C5—C10—C9	−20.3 (5)
N2—C6—C7—C8	−0.6 (5)	C4—C5—C10—C9	161.1 (4)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Br2	0.86	2.37	3.178 (3)	156
N2—H2A···Br1i	0.86	2.35	3.145 (3)	154
C1—H1B···Br1	0.93	2.83	3.611 (4)	143
C9—H9A···Br2	0.93	2.81	3.675 (4)	155
C6—H6A···Br2i	0.93	2.84	3.619 (4)	142
C4—H4A···Br1i	0.93	2.86	3.697 (4)	150
C3—H3A···Br1ii	0.93	2.85	3.677 (4)	149

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯Br2	0.86	2.37	3.178 (3)	156
N2—H2A⋯Br1i	0.86	2.35	3.145 (3)	154
C1—H1B⋯Br1	0.93	2.83	3.611 (4)	143
C9—H9A⋯Br2	0.93	2.81	3.675 (4)	155
C6—H6A⋯Br2i	0.93	2.84	3.619 (4)	142
C4—H4A⋯Br1i	0.93	2.86	3.697 (4)	150
C3—H3A⋯Br1ii	0.93	2.85	3.677 (4)	149

Symmetry codes: (i) ; (ii) .