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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 9| September 2011| Page o2392
doi:10.1107/S160053681103340X

3,3′-Di­methyl-1,1′-[2,2′-bi­pyridine-5,5′-diylbis(methyl­ene)]diimidazol-3-ium bis­­(hexa­fluoro­phosphate)

Sunhong Park,a Suk-Hee Moon,b Tae Ho Kima* and Ki-Min Parka*

aDepartment of Chemistry and Research Institute of Natural Sciences, Gyeongsang National University, Jinju 660-701, Republic of Korea, and bDepartment of Food & Nutrition, Kyungnam College of Information and Technology, Busan 617-701, Republic of Korea
*Correspondence e-mail: thkim@gnu.ac.kr, kmpark@gnu.ac.kr

(Received 14 August 2011; accepted 17 August 2011; online 27 August 2011)

The title compound, C20H22N62+·2PF6−, was prepared by the reaction of 5,5′-bis­(bromo­meth­yl)-2,2′-bipyridine with 1-methyl­imidazole. The main mol­ecule lies on an inversion center located at the mid-point of the C—C bond joining the two pyridine rings. The asymmetric unit therefore contains one half-mol­ecule and one hexa­fluoro­phosphate anion. The dihedral angle between the pyridine and imidazole rings is 76.93 (7)°. In the crystal, weak inter­molecular C—H⋯F hydrogen bonds contribute to the stabilization of the packing.

Related literature

For related syntheses, see: Sambrook et al. (2006[Sambrook, M. R., Curiel, D., Hayes, E. J., Beer, P. D., Pope, S. J. A. & Faulkner, S. (2006). New J. Chem. 30, 1133-1136.]); Zang et al. (2010[Zang, H.-Y., Lan, Y.-Q., Yang, G.-S., Wang, X.-L., Shao, K.-Z., Xu, G.-J. & Su, Z.-M. (2010). CrystEngComm, 12, 434-445.]). For related structures, see: Moon et al. (2011[Moon, S.-H., Kim, T. H. & Park, K.-M. (2011). Acta Cryst. E67, o554.]); Zang et al. (2010[Zang, H.-Y., Lan, Y.-Q., Yang, G.-S., Wang, X.-L., Shao, K.-Z., Xu, G.-J. & Su, Z.-M. (2010). CrystEngComm, 12, 434-445.]). For reference bond lengths, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data

  • C20H22N62+·2PF6−

  • Mr = 636.38

  • Monoclinic, P 21 /c

  • a = 7.5323 (4) Å

  • b = 10.7169 (6) Å

  • c = 15.4602 (9) Å

  • β = 93.922 (1)°

  • V = 1245.07 (12) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.29 mm−1

  • T = 173 K

  • 0.40 × 0.40 × 0.10 mm
Data collection

  • Bruker APEXII CCD diffractometer

  • 7489 measured reflections

  • 2717 independent reflections

  • 1788 reflections with I > 2σ(I)

  • Rint = 0.049
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.117

  • S = 1.02

  • 2717 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C7—H7⋯F1 0.95 2.23 3.111 (3) 154
C7—H7⋯F4 0.95 2.39 3.230 (3) 147
C8—H8⋯F1i 0.95 2.50 3.163 (3) 127
C8—H8⋯F2i 0.95 2.50 3.446 (3) 176
C9—H9⋯F2ii 0.95 2.52 3.240 (3) 133
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2006[Bruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL and DIAMOND (Brandenburg, 1998[Brandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681103340X/lx2201sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053681103340X/lx2201Isup2.hkl

Supporting information file. DOI: 10.1107/S160053681103340X/lx2201Isup3.cml

checkCIF report


Comment top

The title compound was prepared for use as a N-heterocyclic carbene ligand in the formation of coordination polymers in line with similar previously reported compounds (Sambrook et al., 2006; Zang et al., 2010).

In the title compound (Scheme 1, Fig. 1), two pyridine rings are coplanar because the title compound lies on a crystallographic inversion center. The geomeries of the title compound are very similar with those of the previously reported compound (Moon et al., 2011) The dihedral angle between the pyridine and imidazole rings is 76.93 (7)°. All the bond lengths are within normal values (Allen et al., 1987).

The crystal packing (Fig. 2) is stabilized by weak intermolecular C—H···F hydrogen bonds (see, Table 1)

Related literature top

For related syntheses, see: Sambrook et al. (2006); Zang et al. (2010). For related structures, see: Moon et al. (2011); Zang et al. (2010). For reference bond lengths, see: Allen et al. (1987).

Experimental top

A mixture of 1-methylimidazole (0.150 g, 1.83 mmol) and 5,5'-bis(bromomethyl)-2,2'-bipyridine (0.30 g, 0.88 mmol) in 1,4-dioxane (15 ml) was stirred for 10 min and then heated at reflux for 6 h. After cooling to room temperature, Et2O (15 ml) was added and 5,5'-bis((N-methylimidazolium-1-yl)methyl)-2,2'-bipyridine bis(chloride) obtained as a white precipitate was separated by filtration and washed with Et2O. For the anion exchange, an excess of KPF6 was added to the aqueous solution of the chloride salts. After stirring for 1 hr, the title compound as a white precipitate was obtained. X–ray quality single crystals were obtained by slow evaporation of a solution of the title compound in acetonitrile at room temperature.

Refinement top

All H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 0.95 Å, Uiso = 1.2Ueq(C) for aromatic, d(C—H) = 0.99 Å, Uiso = 1.2<U>eq(C) for methylene, and d(C—H) = 0.98 Å, Uiso(H) = 1.5Ueq(C) for methyl protons.

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing displacement ellipsoids drawn at the 50% probability level. Hydrogen bonds are shown as dashed lines. (Symmetry code: i) -x + 1, -y + 2, -z + 1)
[Figure 2] Fig. 2. Crystal packing of the title compound with intermolecular C—H···F hydrogen bonds shown as dashed lines. (Symmetry codes: i) -x + 1, -y + 2, -z + 1; ii) x, -y + 3/2, z + 1/2; iii) -x + 1, -y + 1, -z + 1; iv) -x + 1, y - 1/2, -z + 1/2; v) x, y - 1, z).
3,3'-Dimethyl-1,1'-[2,2'-bipyridine-5,5'-diylbis(methylene)]diimidazol-3-ium bis(hexafluorophosphate) top
Crystal data top
C20H22N62+·2PF6−F(000) = 644
Mr = 636.38Dx = 1.697 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 2214 reflections
a = 7.5323 (4) Åθ = 2.3–27.5°
b = 10.7169 (6) ŵ = 0.29 mm−1
c = 15.4602 (9) ÅT = 173 K
β = 93.922 (1)°Plate, colorless
V = 1245.07 (12) Å30.40 × 0.40 × 0.10 mm
Z = 2
Data collection top
Bruker APEXII CCD
diffractometer		1788 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.049
Graphite monochromatorθmax = 27.0°, θmin = 2.6°
ϕ and ω scansh = −9→9
7489 measured reflectionsk = −13→11
2717 independent reflectionsl = −19→17
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.117H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.0536P)2 + 0.3234P]
where P = (Fo2 + 2Fc2)/3
2717 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.30 e Å−3
0 restraintsΔρmin = −0.29 e Å−3
Crystal data top
C20H22N62+·2PF6−V = 1245.07 (12) Å3
Mr = 636.38Z = 2
Monoclinic, P21/cMo Kα radiation
a = 7.5323 (4) ŵ = 0.29 mm−1
b = 10.7169 (6) ÅT = 173 K
c = 15.4602 (9) Å0.40 × 0.40 × 0.10 mm
β = 93.922 (1)°
Data collection top
Bruker APEXII CCD
diffractometer		1788 reflections with I > 2σ(I)
7489 measured reflectionsRint = 0.049
2717 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.117H-atom parameters constrained
S = 1.02Δρmax = 0.30 e Å−3
2717 reflectionsΔρmin = −0.29 e Å−3
181 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.6669 (2)0.90672 (19)0.45131 (12)0.0314 (5)
N20.4666 (2)0.75139 (19)0.16354 (12)0.0292 (5)
N30.2383 (3)0.7410 (2)0.07124 (12)0.0327 (5)
C10.6823 (3)0.8369 (3)0.38058 (15)0.0335 (6)
H10.79370.79790.37390.040*
C20.5479 (3)0.8172 (2)0.31630 (14)0.0272 (5)
C30.3880 (3)0.8772 (2)0.32510 (14)0.0292 (5)
H30.29240.86750.28230.035*
C40.3687 (3)0.9517 (2)0.39729 (14)0.0272 (5)
H40.26050.99520.40370.033*
C50.5085 (3)0.9623 (2)0.45999 (13)0.0232 (5)
C60.5823 (3)0.7291 (2)0.24282 (15)0.0328 (6)
H6A0.70800.73770.22880.039*
H6B0.56470.64230.26240.039*
C70.3074 (3)0.7000 (2)0.14706 (15)0.0327 (6)
H70.25190.64300.18380.039*
C80.5004 (3)0.8271 (3)0.09592 (16)0.0365 (6)
H80.60480.87550.09050.044*
C90.3580 (3)0.8208 (3)0.03775 (16)0.0393 (6)
H90.34370.8636−0.01610.047*
C100.0635 (3)0.7051 (3)0.03147 (18)0.0451 (7)
H10A0.00590.64730.06990.068*
H10B0.07830.6643−0.02430.068*
H10C−0.01060.77970.02220.068*
P10.04237 (8)0.51966 (6)0.32208 (4)0.03076 (19)
F10.24565 (19)0.51442 (16)0.29682 (10)0.0478 (4)
F20.1084 (2)0.48970 (16)0.42008 (9)0.0504 (4)
F30.0232 (2)0.37450 (15)0.30333 (11)0.0547 (5)
F4−0.0194 (2)0.54954 (16)0.22308 (10)0.0536 (5)
F5−0.1585 (2)0.52519 (18)0.34678 (11)0.0563 (5)
F60.0658 (2)0.66508 (15)0.33975 (12)0.0586 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0241 (10)0.0412 (13)0.0278 (11)0.0060 (9)−0.0061 (8)−0.0057 (9)
N20.0271 (10)0.0340 (12)0.0258 (11)0.0016 (8)−0.0040 (8)−0.0073 (8)
N30.0268 (11)0.0425 (13)0.0279 (11)0.0007 (9)−0.0040 (8)−0.0065 (9)
C10.0228 (12)0.0455 (16)0.0314 (13)0.0080 (11)−0.0035 (10)−0.0055 (11)
C20.0273 (12)0.0298 (13)0.0238 (12)0.0005 (10)−0.0024 (9)0.0013 (10)
C30.0263 (12)0.0341 (14)0.0256 (12)0.0019 (10)−0.0084 (10)−0.0010 (10)
C40.0217 (11)0.0335 (14)0.0259 (12)0.0044 (10)−0.0024 (9)0.0021 (10)
C50.0247 (11)0.0234 (13)0.0210 (11)−0.0002 (9)−0.0021 (9)0.0041 (9)
C60.0274 (13)0.0389 (15)0.0305 (13)0.0065 (11)−0.0088 (10)−0.0061 (11)
C70.0319 (13)0.0380 (15)0.0279 (13)−0.0030 (11)0.0006 (10)−0.0031 (11)
C80.0315 (13)0.0407 (16)0.0369 (14)−0.0113 (11)−0.0010 (11)−0.0016 (11)
C90.0456 (16)0.0418 (17)0.0294 (14)−0.0044 (12)−0.0044 (11)0.0009 (11)
C100.0281 (14)0.063 (2)0.0428 (16)−0.0043 (13)−0.0095 (12)−0.0115 (14)
P10.0257 (3)0.0360 (4)0.0301 (4)0.0002 (3)−0.0017 (3)0.0030 (3)
F10.0296 (8)0.0637 (11)0.0504 (10)0.0063 (7)0.0055 (7)0.0140 (8)
F20.0494 (10)0.0695 (12)0.0314 (9)−0.0041 (8)−0.0042 (7)0.0066 (7)
F30.0684 (11)0.0394 (10)0.0561 (10)−0.0069 (8)0.0020 (9)−0.0042 (7)
F40.0424 (9)0.0776 (13)0.0390 (10)−0.0098 (8)−0.0112 (7)0.0184 (8)
F50.0312 (9)0.0749 (13)0.0637 (12)0.0039 (8)0.0106 (8)0.0159 (9)
F60.0639 (11)0.0363 (10)0.0760 (12)−0.0022 (8)0.0072 (9)−0.0034 (8)
Geometric parameters (Å, º) top
N1—C11.336 (3)C5—C5i1.490 (4)
N1—C51.348 (3)C6—H6A0.9900
N2—C71.329 (3)C6—H6B0.9900
N2—C81.361 (3)C7—H70.9500
N2—C61.474 (3)C8—C91.354 (3)
N3—C71.324 (3)C8—H80.9500
N3—C91.370 (3)C9—H90.9500
N3—C101.466 (3)C10—H10A0.9800
C1—C21.385 (3)C10—H10B0.9800
C1—H10.9500C10—H10C0.9800
C2—C31.380 (3)P1—F51.5869 (16)
C2—C61.513 (3)P1—F31.5872 (17)
C3—C41.388 (3)P1—F61.5899 (18)
C3—H30.9500P1—F21.5947 (16)
C4—C51.386 (3)P1—F41.6014 (16)
C4—H40.9500P1—F11.6069 (15)
C1—N1—C5117.10 (19)N3—C7—H7125.4
C7—N2—C8108.3 (2)N2—C7—H7125.4
C7—N2—C6124.6 (2)C9—C8—N2107.4 (2)
C8—N2—C6127.2 (2)C9—C8—H8126.3
C7—N3—C9108.2 (2)N2—C8—H8126.3
C7—N3—C10124.8 (2)C8—C9—N3107.0 (2)
C9—N3—C10126.9 (2)C8—C9—H9126.5
N1—C1—C2124.9 (2)N3—C9—H9126.5
N1—C1—H1117.5N3—C10—H10A109.5
C2—C1—H1117.5N3—C10—H10B109.5
C3—C2—C1117.3 (2)H10A—C10—H10B109.5
C3—C2—C6124.1 (2)N3—C10—H10C109.5
C1—C2—C6118.6 (2)H10A—C10—H10C109.5
C2—C3—C4119.2 (2)H10B—C10—H10C109.5
C2—C3—H3120.4F5—P1—F390.25 (10)
C4—C3—H3120.4F5—P1—F691.05 (10)
C5—C4—C3119.5 (2)F3—P1—F6178.66 (10)
C5—C4—H4120.2F5—P1—F291.12 (9)
C3—C4—H4120.2F3—P1—F289.70 (9)
N1—C5—C4121.95 (19)F6—P1—F290.60 (9)
N1—C5—C5i116.7 (2)F5—P1—F490.18 (9)
C4—C5—C5i121.4 (2)F3—P1—F490.27 (9)
N2—C6—C2113.67 (19)F6—P1—F489.41 (10)
N2—C6—H6A108.8F2—P1—F4178.70 (9)
C2—C6—H6A108.8F5—P1—F1179.80 (10)
N2—C6—H6B108.8F3—P1—F189.85 (9)
C2—C6—H6B108.8F6—P1—F188.84 (9)
H6A—C6—H6B107.7F2—P1—F189.04 (9)
N3—C7—N2109.1 (2)F4—P1—F189.66 (8)
C5—N1—C1—C2−0.4 (4)C3—C2—C6—N224.8 (3)
N1—C1—C2—C31.9 (4)C1—C2—C6—N2−157.2 (2)
N1—C1—C2—C6−176.2 (2)C9—N3—C7—N20.4 (3)
C1—C2—C3—C4−0.9 (3)C10—N3—C7—N2−179.8 (2)
C6—C2—C3—C4177.2 (2)C8—N2—C7—N3−0.2 (3)
C2—C3—C4—C5−1.5 (3)C6—N2—C7—N3179.07 (19)
C1—N1—C5—C4−2.2 (3)C7—N2—C8—C90.0 (3)
C1—N1—C5—C5i178.7 (3)C6—N2—C8—C9−179.3 (2)
C3—C4—C5—N13.1 (3)N2—C8—C9—N30.2 (3)
C3—C4—C5—C5i−177.8 (3)C7—N3—C9—C8−0.3 (3)
C7—N2—C6—C2−88.2 (3)C10—N3—C9—C8179.8 (2)
C8—N2—C6—C291.0 (3)
Symmetry code: (i) −x+1, −y+2, −z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H7···F10.952.233.111 (3)154
C7—H7···F40.952.393.230 (3)147
C8—H8···F1ii0.952.503.163 (3)127
C8—H8···F2ii0.952.503.446 (3)176
C9—H9···F2iii0.952.523.240 (3)133
Symmetry codes: (ii) −x+1, y+1/2, −z+1/2; (iii) x, −y+3/2, z−1/2.

Experimental details

Crystal data
Chemical formulaC20H22N62+·2PF6−
Mr636.38
Crystal system, space groupMonoclinic, P21/c
Temperature (K)173
a, b, c (Å)7.5323 (4), 10.7169 (6), 15.4602 (9)
β (°) 93.922 (1)
V (Å3)1245.07 (12)
Z2
Radiation typeMo Kα
µ (mm−1)0.29
Crystal size (mm)0.40 × 0.40 × 0.10
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		7489, 2717, 1788
Rint0.049
(sin θ/λ)max (Å−1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.117, 1.02
No. of reflections2717
No. of parameters181
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.30, −0.29

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXTL (Sheldrick, 2008) and DIAMOND (Brandenburg, 1998).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C7—H7···F10.952.233.111 (3)154.2
C7—H7···F40.952.393.230 (3)147.1
C8—H8···F1i0.952.503.163 (3)126.9
C8—H8···F2i0.952.503.446 (3)176.0
C9—H9···F2ii0.952.523.240 (3)132.8
Symmetry codes: (i) −x+1, y+1/2, −z+1/2; (ii) x, −y+3/2, z−1/2.
 

Acknowledgements

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2011–0006413).

References

First citationAllen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19.  CrossRef Web of Science Google Scholar
 First citationBrandenburg, K. (1998). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationBruker (2006). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 9| September 2011| Page o2392
doi:10.1107/S160053681103340X
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