3,3'-[1,2-Phenyl-enebis(methyl-ene)]bis-(1-ethyl-1H-benzimidazol-1-ium) bis-(hexa-flourophosphate).

In the title compound, C(26)H(28)N(4) (2+)·2PF(6) (-), the complete cation is generated by a crystallographic twofold axis. The benz-imidazole ring is almost planar (r.m.s. deviation = 0.0207 Å) and makes dihedral angles of 50.12 (2)° with its symmetry-related component and 65.81 (2)° with the central benzene ring. In the crystal, mol-ecules are linked into a three-dimensional network by C-H⋯F inter-actions. A π-π inter-action with a centroid-centroid distance of 3.530 (1) Å is observed. Four F atoms of the hexa-fluoro-phosphate anion are disordered over two sets of sites in a 0.889 (6):0.111 (6) ratio.

Related literature

For the biological applications of benzimidazoles, see: Narasimhan et al. (2012 ▶). For a related structure, see: Haque et al. (2012 ▶).

Experimental

Crystal data

C26H28N4 2+·2PF6 −

M = 686.46

Monoclinic,

a = 23.2016 (5) Å

b = 8.1526 (2) Å

c = 16.9992 (4) Å

β = 121.274 (1)°

V = 2748.23 (11) Å3

Z = 4

Mo Kα radiation

μ = 0.27 mm−1

T = 100 K

0.26 × 0.26 × 0.14 mm

Data collection

Bruker SMART APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T min = 0.933, T max = 0.963

14787 measured reflections

3921 independent reflections

3156 reflections with I > 2σ(I)

R int = 0.037

Refinement

R[F 2 > 2σ(F 2)] = 0.046

wR(F 2) = 0.098

S = 1.05

3921 reflections

217 parameters

H-atom parameters constrained

Δρmax = 0.48 e Å−3

Δρmin = −0.35 e Å−3

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812019344/hb6760sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812019344/hb6760Isup2.hkl

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

C26H28N42+·2PF6−	F(000) = 1400
Mr = 686.46	Dx = 1.659 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3899 reflections
a = 23.2016 (5) Å	θ = 2.5–29.7°
b = 8.1526 (2) Å	µ = 0.27 mm−1
c = 16.9992 (4) Å	T = 100 K
β = 121.274 (1)°	Block, colourless
V = 2748.23 (11) Å3	0.26 × 0.26 × 0.14 mm
Z = 4

Bruker SMART APEXII CCD diffractometer	3921 independent reflections
Radiation source: fine-focus sealed tube	3156 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.037
φ and ω scans	θmax = 29.8°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −32→31
Tmin = 0.933, Tmax = 0.963	k = −11→9
14787 measured reflections	l = −23→23

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098	H-atom parameters constrained
S = 1.05	w = 1/[σ2(Fo2) + (0.0339P)2 + 4.2095P] where P = (Fo2 + 2Fc2)/3
3921 reflections	(Δ/σ)max = 0.001
217 parameters	Δρmax = 0.48 e Å−3
0 restraints	Δρmin = −0.35 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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	Occ. (<1)
P1	0.89811 (2)	0.80829 (6)	0.89390 (3)	0.01579 (11)
F5	0.84112 (5)	0.94532 (13)	0.83897 (7)	0.0220 (2)
F6	0.95467 (6)	0.67136 (15)	0.94831 (8)	0.0323 (3)
F1	0.95400 (8)	0.92423 (17)	0.89472 (17)	0.0309 (5)	0.889 (6)
F2	0.91321 (10)	0.8889 (2)	0.98909 (10)	0.0303 (5)	0.889 (6)
F3	0.84260 (11)	0.6929 (2)	0.8940 (2)	0.0311 (5)	0.889 (6)
F4	0.88302 (12)	0.7290 (2)	0.79927 (10)	0.0314 (5)	0.889 (6)
F1A	0.9350 (7)	0.9043 (15)	0.8457 (11)	0.024 (3)*	0.111 (6)
F2A	0.9323 (8)	0.9133 (18)	0.9770 (10)	0.032 (4)*	0.111 (6)
F4A	0.8573 (8)	0.7032 (18)	0.7950 (10)	0.029 (3)*	0.111 (6)
F3A	0.8547 (9)	0.713 (2)	0.9237 (11)	0.024 (4)*	0.111 (6)
N1	0.16728 (7)	0.66335 (17)	1.09095 (9)	0.0146 (3)
N2	0.10920 (7)	0.67626 (18)	0.94040 (9)	0.0154 (3)
C1	0.10867 (8)	0.7060 (2)	1.01737 (11)	0.0157 (3)
H1A	0.0717	0.7513	1.0192	0.019*
C2	0.20844 (8)	0.5997 (2)	1.06084 (11)	0.0142 (3)
C3	0.27289 (8)	0.5312 (2)	1.10913 (12)	0.0174 (3)
H3A	0.2982	0.5254	1.1744	0.021*
C4	0.29766 (9)	0.4723 (2)	1.05606 (13)	0.0206 (4)
H4A	0.3410	0.4226	1.0859	0.025*
C5	0.26085 (9)	0.4833 (2)	0.95923 (13)	0.0212 (4)
H5A	0.2802	0.4424	0.9257	0.025*
C6	0.19723 (9)	0.5525 (2)	0.91211 (12)	0.0174 (3)
H6A	0.1723	0.5610	0.8469	0.021*
C7	0.17168 (8)	0.6091 (2)	0.96517 (11)	0.0150 (3)
C8	0.05184 (8)	0.6967 (2)	0.84619 (11)	0.0163 (3)
H8A	0.0663	0.7624	0.8105	0.020*
H8B	0.0157	0.7582	0.8480	0.020*
C9	0.02370 (8)	0.5336 (2)	0.79767 (11)	0.0151 (3)
C10	0.04406 (8)	0.3851 (2)	0.84445 (12)	0.0178 (3)
H10A	0.0740	0.3845	0.9093	0.021*
C11	0.02104 (9)	0.2372 (2)	0.79734 (12)	0.0200 (4)
H11A	0.0342	0.1364	0.8301	0.024*
C12	0.18631 (9)	0.6741 (2)	1.18835 (11)	0.0186 (3)
H12A	0.2176	0.7675	1.2179	0.022*
H12B	0.2104	0.5727	1.2208	0.022*
C13	0.12542 (9)	0.6968 (2)	1.19816 (13)	0.0212 (4)
H13A	0.1402	0.7015	1.2636	0.032*
H13B	0.0944	0.6044	1.1692	0.032*
H13C	0.1024	0.7992	1.1681	0.032*

	U11	U22	U33	U12	U13	U23
P1	0.0129 (2)	0.0162 (2)	0.0174 (2)	0.00054 (16)	0.00725 (17)	0.00099 (17)
F5	0.0197 (5)	0.0208 (5)	0.0221 (5)	0.0054 (4)	0.0084 (4)	0.0053 (4)
F6	0.0233 (6)	0.0279 (6)	0.0390 (7)	0.0116 (5)	0.0115 (5)	0.0080 (5)
F1	0.0212 (8)	0.0261 (7)	0.0505 (14)	−0.0047 (6)	0.0224 (9)	−0.0001 (7)
F2	0.0303 (9)	0.0381 (9)	0.0169 (6)	0.0070 (7)	0.0083 (6)	−0.0039 (6)
F3	0.0263 (9)	0.0207 (8)	0.0519 (15)	−0.0042 (7)	0.0244 (11)	0.0045 (10)
F4	0.0382 (11)	0.0331 (9)	0.0228 (7)	0.0058 (8)	0.0157 (7)	−0.0062 (6)
N1	0.0127 (6)	0.0161 (7)	0.0134 (6)	0.0006 (5)	0.0056 (5)	−0.0010 (5)
N2	0.0112 (6)	0.0185 (7)	0.0137 (6)	0.0007 (5)	0.0044 (5)	−0.0010 (6)
C1	0.0122 (7)	0.0179 (8)	0.0151 (7)	0.0008 (6)	0.0057 (6)	−0.0011 (6)
C2	0.0126 (7)	0.0133 (7)	0.0157 (7)	−0.0015 (6)	0.0067 (6)	−0.0014 (6)
C3	0.0132 (8)	0.0175 (8)	0.0175 (8)	0.0002 (6)	0.0051 (7)	0.0007 (7)
C4	0.0131 (8)	0.0216 (9)	0.0238 (9)	0.0034 (7)	0.0074 (7)	0.0021 (7)
C5	0.0198 (9)	0.0219 (9)	0.0268 (9)	0.0000 (7)	0.0155 (8)	−0.0023 (8)
C6	0.0168 (8)	0.0189 (8)	0.0161 (8)	−0.0025 (6)	0.0082 (7)	−0.0023 (7)
C7	0.0112 (7)	0.0142 (8)	0.0165 (8)	−0.0017 (6)	0.0050 (6)	−0.0009 (6)
C8	0.0117 (7)	0.0202 (8)	0.0114 (7)	−0.0004 (6)	0.0022 (6)	0.0006 (6)
C9	0.0102 (7)	0.0201 (8)	0.0143 (8)	−0.0008 (6)	0.0059 (6)	−0.0009 (6)
C10	0.0117 (8)	0.0235 (9)	0.0147 (8)	−0.0010 (6)	0.0045 (6)	0.0018 (7)
C11	0.0146 (8)	0.0191 (8)	0.0227 (9)	0.0014 (6)	0.0072 (7)	0.0042 (7)
C12	0.0193 (8)	0.0216 (9)	0.0121 (7)	0.0021 (7)	0.0062 (7)	−0.0011 (7)
C13	0.0260 (9)	0.0195 (9)	0.0227 (9)	0.0017 (7)	0.0158 (8)	0.0017 (7)

P1—F2A	1.481 (14)	C4—C5	1.410 (3)
P1—F3A	1.552 (19)	C4—H4A	0.9500
P1—F4	1.5947 (14)	C5—C6	1.382 (2)
P1—F3	1.5957 (18)	C5—H5A	0.9500
P1—F1	1.5987 (13)	C6—C7	1.390 (2)
P1—F6	1.6011 (12)	C6—H6A	0.9500
P1—F2	1.6077 (15)	C8—C9	1.522 (2)
P1—F5	1.6082 (11)	C8—H8A	0.9900
P1—F1A	1.656 (11)	C8—H8B	0.9900
P1—F4A	1.674 (14)	C9—C10	1.390 (2)
N1—C1	1.330 (2)	C9—C9i	1.409 (3)
N1—C2	1.397 (2)	C10—C11	1.391 (3)
N1—C12	1.478 (2)	C10—H10A	0.9500
N2—C1	1.337 (2)	C11—C11i	1.383 (3)
N2—C7	1.395 (2)	C11—H11A	0.9500
N2—C8	1.467 (2)	C12—C13	1.518 (2)
C1—H1A	0.9500	C12—H12A	0.9900
C2—C7	1.392 (2)	C12—H12B	0.9900
C2—C3	1.395 (2)	C13—H13A	0.9800
C3—C4	1.383 (2)	C13—H13B	0.9800
C3—H3A	0.9500	C13—H13C	0.9800
F2A—P1—F3A	95.5 (8)	N1—C1—H1A	124.8
F2A—P1—F4	157.6 (7)	N2—C1—H1A	124.8
F3A—P1—F4	106.7 (6)	C7—C2—C3	121.92 (15)
F2A—P1—F3	111.9 (7)	C7—C2—N1	106.67 (14)
F4—P1—F3	90.44 (11)	C3—C2—N1	131.37 (15)
F2A—P1—F1	67.6 (7)	C4—C3—C2	115.88 (16)
F3A—P1—F1	162.7 (6)	C4—C3—H3A	122.1
F4—P1—F1	90.05 (9)	C2—C3—H3A	122.1
F3—P1—F1	179.50 (11)	C3—C4—C5	122.29 (16)
F2A—P1—F6	88.8 (6)	C3—C4—H4A	118.9
F3A—P1—F6	86.5 (7)	C5—C4—H4A	118.9
F4—P1—F6	89.14 (8)	C6—C5—C4	121.35 (16)
F3—P1—F6	90.47 (9)	C6—C5—H5A	119.3
F1—P1—F6	89.39 (7)	C4—C5—H5A	119.3
F3A—P1—F2	73.4 (6)	C5—C6—C7	116.48 (16)
F4—P1—F2	179.76 (10)	C5—C6—H6A	121.8
F3—P1—F2	89.66 (11)	C7—C6—H6A	121.8
F1—P1—F2	89.86 (9)	C6—C7—C2	122.06 (15)
F6—P1—F2	91.07 (7)	C6—C7—N2	131.37 (16)
F2A—P1—F5	91.4 (6)	C2—C7—N2	106.53 (14)
F3A—P1—F5	93.4 (7)	N2—C8—C9	112.54 (14)
F4—P1—F5	90.69 (7)	N2—C8—H8A	109.1
F3—P1—F5	89.39 (9)	C9—C8—H8A	109.1
F1—P1—F5	90.75 (7)	N2—C8—H8B	109.1
F6—P1—F5	179.78 (9)	C9—C8—H8B	109.1
F2—P1—F5	89.10 (7)	H8A—C8—H8B	107.8
F2A—P1—F1A	92.3 (7)	C10—C9—C9i	119.25 (10)
F3A—P1—F1A	171.2 (7)	C10—C9—C8	121.89 (14)
F4—P1—F1A	65.9 (5)	C9i—C9—C8	118.85 (9)
F3—P1—F1A	154.6 (5)	C9—C10—C11	120.70 (15)
F6—P1—F1A	97.8 (4)	C9—C10—H10A	119.6
F2—P1—F1A	114.0 (5)	C11—C10—H10A	119.7
F5—P1—F1A	82.2 (4)	C11i—C11—C10	119.87 (10)
F2A—P1—F4A	175.5 (8)	C11i—C11—H11A	120.1
F3A—P1—F4A	86.9 (7)	C10—C11—H11A	120.1
F3—P1—F4A	70.3 (5)	N1—C12—C13	112.13 (14)
F1—P1—F4A	110.2 (5)	N1—C12—H12A	109.2
F6—P1—F4A	95.2 (5)	C13—C12—H12A	109.2
F2—P1—F4A	159.0 (6)	N1—C12—H12B	109.2
F5—P1—F4A	84.6 (5)	C13—C12—H12B	109.2
F1A—P1—F4A	85.1 (6)	H12A—C12—H12B	107.9
C1—N1—C2	108.21 (13)	C12—C13—H13A	109.5
C1—N1—C12	127.07 (14)	C12—C13—H13B	109.5
C2—N1—C12	124.68 (14)	H13A—C13—H13B	109.5
C1—N2—C7	108.18 (14)	C12—C13—H13C	109.5
C1—N2—C8	125.72 (14)	H13A—C13—H13C	109.5
C7—N2—C8	125.88 (14)	H13B—C13—H13C	109.5
N1—C1—N2	110.39 (14)
C2—N1—C1—N2	−0.89 (19)	N1—C2—C7—C6	−178.67 (15)
C12—N1—C1—N2	−178.83 (15)	C3—C2—C7—N2	177.24 (15)
C7—N2—C1—N1	0.45 (19)	N1—C2—C7—N2	−0.69 (18)
C8—N2—C1—N1	175.33 (15)	C1—N2—C7—C6	177.89 (18)
C1—N1—C2—C7	0.97 (18)	C8—N2—C7—C6	3.0 (3)
C12—N1—C2—C7	178.98 (15)	C1—N2—C7—C2	0.18 (18)
C1—N1—C2—C3	−176.69 (18)	C8—N2—C7—C2	−174.70 (15)
C12—N1—C2—C3	1.3 (3)	C1—N2—C8—C9	−109.15 (18)
C7—C2—C3—C4	−0.5 (2)	C7—N2—C8—C9	64.8 (2)
N1—C2—C3—C4	176.88 (17)	N2—C8—C9—C10	9.8 (2)
C2—C3—C4—C5	1.2 (3)	N2—C8—C9—C9i	−169.32 (17)
C3—C4—C5—C6	−0.8 (3)	C9i—C9—C10—C11	3.6 (3)
C4—C5—C6—C7	−0.4 (3)	C8—C9—C10—C11	−175.57 (16)
C5—C6—C7—C2	1.2 (3)	C9—C10—C11—C11i	1.8 (3)
C5—C6—C7—N2	−176.25 (17)	C1—N1—C12—C13	15.8 (2)
C3—C2—C7—C6	−0.7 (3)	C2—N1—C12—C13	−161.87 (15)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···F6ii	0.95	2.42	3.142 (3)	133
C3—H3A···F5iii	0.95	2.45	3.374 (2)	166
C5—H5A···F5iv	0.95	2.52	3.420 (3)	159
C6—H6A···F4v	0.95	2.53	3.392 (2)	151
C8—H8B···F1ii	0.99	2.39	3.350 (3)	164
C13—H13C···F1vi	0.98	2.55	3.523 (2)	174
C13—H13C···F5vi	0.98	2.50	3.166 (2)	125

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯F6i	0.95	2.42	3.142 (3)	133
C3—H3A⋯F5ii	0.95	2.45	3.374 (2)	166
C5—H5A⋯F5iii	0.95	2.52	3.420 (3)	159
C6—H6A⋯F4iv	0.95	2.53	3.392 (2)	151
C8—H8B⋯F1i	0.99	2.39	3.350 (3)	164
C13—H13C⋯F1v	0.98	2.55	3.523 (2)	174
C13—H13C⋯F5v	0.98	2.50	3.166 (2)	125

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) ; (v) .