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organic compounds
3,3′-Di-n-butyl-1,1′-(p-phenylenedimethylene)diimidazolium bis(hexafluorophosphate)
aSchool of Chemical Science, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my
The N-heterocyclic carbene compound, C22H32N42+·2PF6−, consists of one half of the N-heterocyclic carbene dication and one hexafluorophosphate anion. The dication lies across a crystallographic inversion center. The imidazole ring is twisted away from the central benzene ring, making a dihedral angle of 76.23 (6)°. The hexafluorophosphate anions link the cations into a three-dimensional network via intermolecular C—H⋯F hydrogen bonds. A weak C—H⋯π interaction further stabilizes the crystal structure.
of the titleRelated literature
For background to N-heterocyclic see: Arduengo et al. (1991); Papini et al. (2008
). For applications of N-heterocyclic carbene derivatives, see: Meyer et al. (2009
); Barnard et al. (2004
); Lin & Vasam (2007
). For a related structure, see: Washeel et al. (2010
). For the stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986
).
Experimental
Crystal data
|
Refinement
|
|
Data collection: APEX2 (Bruker, 2009); cell 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
).
Supporting information
10.1107/S1600536810008536/sj2739sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810008536/sj2739Isup2.hkl
To a solution of p-xylylene dichloride (1 g, 5.75 mmol) in 30 ml of 1,4-dioxane, 1-butylimidazole (1.42 g, 11.5 mmol) was added. The mixture was refluxed at 373 K for 24 h. The slurry product was isolated by decantation then washed with diethyl ether (2x3 ml). KPF6 (2.1 g, 11.5 mmol) in 20 ml of distilled water was then added with stirring for 1 h and the suspension was left standing overnight. The white precipitate was filtered, washed with distilled water several times and recrystallized from acetonitrile. The yield was found to be 2.30 g (62.7 %), m.p.: 411-413 K. Crystals suitable for X-ray was obtained by slow evaporation of the salt solution in acetonitrile at 281 K.
The H1A and H3A hydrogen atoms were located from a difference Fourier map and refined freely. The remaining H atoms were positioned geometrically and refined using a riding model, with C–H = 0.93 or 0.97 Å and Uiso(H) = 1.2 or 1.5 Ueq(C). A rotating group model was applied for the methyl groups. Short intermolecular F1···C5 and F1···C7 of 2.8636 (12) and 2.8798 (13) Å contacts are observed.
Data collection: APEX2 (Bruker, 2009); cell
SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).C22H32N42+·2PF6− | F(000) = 660 |
Mr = 642.46 | Dx = 1.548 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 8699 reflections |
a = 8.9802 (5) Å | θ = 3.3–35.1° |
b = 17.8421 (10) Å | µ = 0.26 mm−1 |
c = 9.3637 (5) Å | T = 100 K |
β = 113.233 (1)° | Block, colourless |
V = 1378.64 (13) Å3 | 0.37 × 0.25 × 0.20 mm |
Z = 2 |
Bruker APEX Duo CCD area detector diffractometer | 5550 independent reflections |
Radiation source: fine-focus sealed tube | 4750 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
ϕ and ω scans | θmax = 34.0°, θmin = 3.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −12→14 |
Tmin = 0.910, Tmax = 0.950 | k = −25→28 |
21938 measured reflections | l = −14→14 |
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)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.121 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.10 | w = 1/[σ2(Fo2) + (0.0669P)2 + 0.3404P] where P = (Fo2 + 2Fc2)/3 |
5550 reflections | (Δ/σ)max < 0.001 |
190 parameters | Δρmax = 0.52 e Å−3 |
0 restraints | Δρmin = −0.35 e Å−3 |
C22H32N42+·2PF6− | V = 1378.64 (13) Å3 |
Mr = 642.46 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 8.9802 (5) Å | µ = 0.26 mm−1 |
b = 17.8421 (10) Å | T = 100 K |
c = 9.3637 (5) Å | 0.37 × 0.25 × 0.20 mm |
β = 113.233 (1)° |
Bruker APEX Duo CCD area detector diffractometer | 5550 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 4750 reflections with I > 2σ(I) |
Tmin = 0.910, Tmax = 0.950 | Rint = 0.027 |
21938 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.121 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.10 | Δρmax = 0.52 e Å−3 |
5550 reflections | Δρmin = −0.35 e Å−3 |
190 parameters |
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 esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 | ||
P1 | 0.24993 (3) | 0.644667 (14) | 0.41525 (3) | 0.01504 (7) | |
F1 | 0.17538 (13) | 0.58756 (4) | 0.27368 (9) | 0.0377 (2) | |
F2 | 0.32152 (11) | 0.70282 (5) | 0.55641 (8) | 0.03461 (19) | |
F3 | 0.40070 (10) | 0.59059 (5) | 0.49878 (11) | 0.0363 (2) | |
F4 | 0.15300 (10) | 0.60287 (5) | 0.50374 (10) | 0.03387 (18) | |
F5 | 0.34534 (10) | 0.68616 (5) | 0.32536 (10) | 0.03212 (18) | |
F6 | 0.09980 (9) | 0.70032 (5) | 0.33174 (9) | 0.02912 (16) | |
N1 | −0.09308 (9) | −0.12292 (5) | 0.43634 (9) | 0.01428 (14) | |
N2 | 0.12122 (9) | −0.11365 (5) | 0.38494 (10) | 0.01434 (14) | |
C1 | 0.42820 (12) | −0.01546 (6) | 0.34135 (11) | 0.01608 (16) | |
C2 | 0.39498 (11) | −0.06136 (5) | 0.44620 (11) | 0.01435 (15) | |
C3 | 0.46724 (12) | −0.04565 (6) | 0.60501 (11) | 0.01585 (16) | |
C4 | 0.28430 (11) | −0.12854 (6) | 0.38858 (12) | 0.01716 (17) | |
H4A | 0.2753 | −0.1415 | 0.2849 | 0.021* | |
H4B | 0.3314 | −0.1710 | 0.4560 | 0.021* | |
C5 | 0.05423 (11) | −0.15095 (5) | 0.46797 (11) | 0.01380 (15) | |
H5A | 0.1022 | −0.1900 | 0.5365 | 0.017* | |
C6 | 0.01313 (13) | −0.05969 (6) | 0.29775 (13) | 0.01997 (18) | |
H6A | 0.0295 | −0.0256 | 0.2301 | 0.024* | |
C7 | −0.12157 (12) | −0.06587 (6) | 0.32955 (13) | 0.01986 (18) | |
H7A | −0.2152 | −0.0371 | 0.2873 | 0.024* | |
C8 | −0.20778 (12) | −0.14960 (6) | 0.50215 (12) | 0.01732 (17) | |
H8A | −0.2538 | −0.1069 | 0.5344 | 0.021* | |
H8B | −0.1501 | −0.1799 | 0.5934 | 0.021* | |
C9 | −0.34402 (11) | −0.19587 (6) | 0.38501 (12) | 0.01788 (17) | |
H9A | −0.4209 | −0.2086 | 0.4304 | 0.021* | |
H9B | −0.4004 | −0.1652 | 0.2940 | 0.021* | |
C10 | −0.28848 (13) | −0.26785 (6) | 0.33359 (13) | 0.02143 (19) | |
H10A | −0.3792 | −0.2892 | 0.2475 | 0.026* | |
H10B | −0.2049 | −0.2557 | 0.2961 | 0.026* | |
C11 | −0.22253 (16) | −0.32643 (7) | 0.46144 (18) | 0.0314 (3) | |
H11B | −0.1973 | −0.3714 | 0.4194 | 0.047* | |
H11C | −0.3025 | −0.3372 | 0.5028 | 0.047* | |
H11D | −0.1262 | −0.3076 | 0.5428 | 0.047* | |
H1A | 0.372 (2) | −0.0256 (10) | 0.227 (2) | 0.026 (4)* | |
H3A | 0.447 (2) | −0.0786 (10) | 0.671 (2) | 0.025 (4)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
P1 | 0.01633 (12) | 0.01343 (12) | 0.01512 (11) | 0.00062 (7) | 0.00596 (9) | 0.00052 (7) |
F1 | 0.0666 (6) | 0.0170 (3) | 0.0251 (4) | −0.0065 (3) | 0.0134 (4) | −0.0070 (3) |
F2 | 0.0451 (5) | 0.0276 (4) | 0.0184 (3) | −0.0044 (3) | −0.0011 (3) | −0.0044 (3) |
F3 | 0.0324 (4) | 0.0346 (4) | 0.0439 (5) | 0.0182 (3) | 0.0173 (3) | 0.0191 (4) |
F4 | 0.0300 (4) | 0.0430 (5) | 0.0339 (4) | −0.0048 (3) | 0.0182 (3) | 0.0085 (3) |
F5 | 0.0322 (4) | 0.0337 (4) | 0.0369 (4) | −0.0006 (3) | 0.0204 (3) | 0.0123 (3) |
F6 | 0.0231 (3) | 0.0298 (4) | 0.0278 (3) | 0.0112 (3) | 0.0029 (3) | 0.0008 (3) |
N1 | 0.0115 (3) | 0.0145 (3) | 0.0169 (3) | 0.0003 (2) | 0.0056 (3) | 0.0004 (3) |
N2 | 0.0127 (3) | 0.0128 (3) | 0.0185 (3) | −0.0015 (2) | 0.0071 (3) | −0.0015 (3) |
C1 | 0.0163 (4) | 0.0168 (4) | 0.0167 (4) | −0.0029 (3) | 0.0081 (3) | −0.0029 (3) |
C2 | 0.0125 (3) | 0.0133 (4) | 0.0192 (4) | −0.0020 (3) | 0.0083 (3) | −0.0030 (3) |
C3 | 0.0168 (4) | 0.0158 (4) | 0.0178 (4) | −0.0029 (3) | 0.0099 (3) | −0.0010 (3) |
C4 | 0.0147 (4) | 0.0144 (4) | 0.0258 (4) | −0.0035 (3) | 0.0116 (3) | −0.0058 (3) |
C5 | 0.0118 (3) | 0.0133 (4) | 0.0164 (4) | −0.0002 (3) | 0.0056 (3) | −0.0003 (3) |
C6 | 0.0180 (4) | 0.0168 (4) | 0.0248 (4) | −0.0006 (3) | 0.0082 (3) | 0.0057 (3) |
C7 | 0.0156 (4) | 0.0163 (4) | 0.0265 (5) | 0.0023 (3) | 0.0070 (3) | 0.0057 (3) |
C8 | 0.0142 (4) | 0.0214 (4) | 0.0186 (4) | −0.0014 (3) | 0.0089 (3) | −0.0021 (3) |
C9 | 0.0124 (4) | 0.0197 (4) | 0.0218 (4) | −0.0007 (3) | 0.0071 (3) | −0.0008 (3) |
C10 | 0.0196 (4) | 0.0212 (5) | 0.0263 (5) | −0.0028 (3) | 0.0121 (4) | −0.0044 (4) |
C11 | 0.0290 (6) | 0.0223 (5) | 0.0447 (7) | 0.0055 (4) | 0.0166 (5) | 0.0043 (5) |
P1—F3 | 1.5939 (8) | C4—H4A | 0.9700 |
P1—F1 | 1.5948 (8) | C4—H4B | 0.9700 |
P1—F5 | 1.5999 (8) | C5—H5A | 0.9300 |
P1—F2 | 1.6020 (8) | C6—C7 | 1.3595 (15) |
P1—F4 | 1.6029 (8) | C6—H6A | 0.9300 |
P1—F6 | 1.6073 (7) | C7—H7A | 0.9300 |
N1—C5 | 1.3337 (12) | C8—C9 | 1.5241 (14) |
N1—C7 | 1.3782 (13) | C8—H8A | 0.9700 |
N1—C8 | 1.4725 (12) | C8—H8B | 0.9700 |
N2—C5 | 1.3335 (12) | C9—C10 | 1.5229 (15) |
N2—C6 | 1.3822 (13) | C9—H9A | 0.9700 |
N2—C4 | 1.4755 (12) | C9—H9B | 0.9700 |
C1—C3i | 1.3966 (13) | C10—C11 | 1.5222 (17) |
C1—C2 | 1.3981 (13) | C10—H10A | 0.9700 |
C1—H1A | 1.005 (17) | C10—H10B | 0.9700 |
C2—C3 | 1.3964 (13) | C11—H11B | 0.9600 |
C2—C4 | 1.5141 (13) | C11—H11C | 0.9600 |
C3—C1i | 1.3966 (13) | C11—H11D | 0.9600 |
C3—H3A | 0.925 (17) | ||
F3—P1—F1 | 91.03 (5) | H4A—C4—H4B | 107.9 |
F3—P1—F5 | 90.61 (5) | N2—C5—N1 | 108.63 (8) |
F1—P1—F5 | 89.70 (5) | N2—C5—H5A | 125.7 |
F3—P1—F2 | 90.02 (5) | N1—C5—H5A | 125.7 |
F1—P1—F2 | 178.91 (5) | C7—C6—N2 | 107.00 (9) |
F5—P1—F2 | 90.60 (5) | C7—C6—H6A | 126.5 |
F3—P1—F4 | 89.66 (5) | N2—C6—H6A | 126.5 |
F1—P1—F4 | 89.82 (5) | C6—C7—N1 | 106.99 (9) |
F5—P1—F4 | 179.45 (5) | C6—C7—H7A | 126.5 |
F2—P1—F4 | 89.87 (5) | N1—C7—H7A | 126.5 |
F3—P1—F6 | 179.09 (5) | N1—C8—C9 | 111.68 (8) |
F1—P1—F6 | 89.64 (5) | N1—C8—H8A | 109.3 |
F5—P1—F6 | 88.78 (4) | C9—C8—H8A | 109.3 |
F2—P1—F6 | 89.31 (4) | N1—C8—H8B | 109.3 |
F4—P1—F6 | 90.95 (5) | C9—C8—H8B | 109.3 |
C5—N1—C7 | 108.79 (8) | H8A—C8—H8B | 107.9 |
C5—N1—C8 | 125.60 (8) | C10—C9—C8 | 114.48 (8) |
C7—N1—C8 | 125.60 (8) | C10—C9—H9A | 108.6 |
C5—N2—C6 | 108.59 (8) | C8—C9—H9A | 108.6 |
C5—N2—C4 | 124.66 (8) | C10—C9—H9B | 108.6 |
C6—N2—C4 | 126.75 (8) | C8—C9—H9B | 108.6 |
C3i—C1—C2 | 120.28 (9) | H9A—C9—H9B | 107.6 |
C3i—C1—H1A | 120.5 (10) | C11—C10—C9 | 113.87 (9) |
C2—C1—H1A | 119.2 (10) | C11—C10—H10A | 108.8 |
C3—C2—C1 | 119.47 (8) | C9—C10—H10A | 108.8 |
C3—C2—C4 | 120.16 (9) | C11—C10—H10B | 108.8 |
C1—C2—C4 | 120.36 (8) | C9—C10—H10B | 108.8 |
C2—C3—C1i | 120.25 (9) | H10A—C10—H10B | 107.7 |
C2—C3—H3A | 117.1 (11) | C10—C11—H11B | 109.5 |
C1i—C3—H3A | 122.5 (11) | C10—C11—H11C | 109.5 |
N2—C4—C2 | 111.82 (8) | H11B—C11—H11C | 109.5 |
N2—C4—H4A | 109.3 | C10—C11—H11D | 109.5 |
C2—C4—H4A | 109.3 | H11B—C11—H11D | 109.5 |
N2—C4—H4B | 109.3 | H11C—C11—H11D | 109.5 |
C2—C4—H4B | 109.3 | ||
C3i—C1—C2—C3 | −0.02 (16) | C8—N1—C5—N2 | 178.85 (8) |
C3i—C1—C2—C4 | −178.77 (9) | C5—N2—C6—C7 | −0.48 (12) |
C1—C2—C3—C1i | 0.02 (16) | C4—N2—C6—C7 | 179.81 (9) |
C4—C2—C3—C1i | 178.77 (9) | N2—C6—C7—N1 | 0.50 (12) |
C5—N2—C4—C2 | −118.10 (10) | C5—N1—C7—C6 | −0.35 (12) |
C6—N2—C4—C2 | 61.57 (13) | C8—N1—C7—C6 | −179.15 (9) |
C3—C2—C4—N2 | 78.63 (11) | C5—N1—C8—C9 | −104.24 (11) |
C1—C2—C4—N2 | −102.63 (10) | C7—N1—C8—C9 | 74.36 (12) |
C6—N2—C5—N1 | 0.26 (11) | N1—C8—C9—C10 | 63.05 (11) |
C4—N2—C5—N1 | 179.98 (8) | C8—C9—C10—C11 | 67.80 (12) |
C7—N1—C5—N2 | 0.05 (11) |
Symmetry code: (i) −x+1, −y, −z+1. |
Table 1. Hydrogen bond geometry (Å, °). Cg1 is centroids of benzene ring C1-C2-C3-C1A-C2A-C3A. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1A···F3ii | 1.004 (17) | 2.532 (18) | 3.3945 (14) | 143.8 (15) |
C4—H4A···F4ii | 0.97 | 2.52 | 3.3516 (14) | 144 |
C4—H4B···F2iii | 0.97 | 2.45 | 3.3497 (14) | 153 |
C7—H7A···F1iv | 0.93 | 2.36 | 2.8798 (13) | 115 |
C8—H8B···F6v | 0.97 | 2.49 | 3.3537 (13) | 148 |
C8—H8A···Cg1vi | 0.97 | 2.84 | 3.7376 (12) | 154 |
C8—H8A···Cg1vii | 0.97 | 2.84 | 3.7376 (12) | 154 |
Symmetry codes: (ii) x, −y+1/2, z−1/2; (iii) x, y−1, z; (iv) −x, y−1/2, −z+1/2; (v) x, −y+1/2, z+1/2; (vi) x−1, y, z; (vii) −x, −y, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C22H32N42+·2PF6− |
Mr | 642.46 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 8.9802 (5), 17.8421 (10), 9.3637 (5) |
β (°) | 113.233 (1) |
V (Å3) | 1378.64 (13) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.26 |
Crystal size (mm) | 0.37 × 0.25 × 0.20 |
Data collection | |
Diffractometer | Bruker APEX Duo CCD area detector diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.910, 0.950 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 21938, 5550, 4750 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.787 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.121, 1.10 |
No. of reflections | 5550 |
No. of parameters | 190 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.52, −0.35 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
Table 1. Hydrogen bond geometry (Å, °). Cg1 is centroids of benzene ring C1-C2-C3-C1A-C2A-C3A. |
D—H···A | D—H | H···A | D···A | D—H···A |
C1—H1A···F3i | 1.004 (17) | 2.532 (18) | 3.3945 (14) | 143.8 (15) |
C4—H4A···F4i | 0.9700 | 2.5200 | 3.3516 (14) | 144.00 |
C4—H4B···F2ii | 0.9700 | 2.4500 | 3.3497 (14) | 153.00 |
C7—H7A···F1iii | 0.9300 | 2.3600 | 2.8798 (13) | 115.00 |
C8—H8B···F6iv | 0.9700 | 2.4900 | 3.3537 (13) | 148.00 |
C8—H8A···Cg1v | 0.97 | 2.84 | 3.7376 (12) | 154 |
C8—H8A···Cg1vi | 0.97 | 2.84 | 3.7376 (12) | 154 |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) x, y−1, z; (iii) −x, y−1/2, −z+1/2; (iv) x, −y+1/2, z+1/2; (v) x−1, y, z; (vi) −x, −y, −z+1. |
Acknowledgements
RAH, AW and SFN thank Universiti Sains Malaysia (USM) for the FRGS fund (203/PKIMIA/671115). HKF and CSY thank USM for the Research University Golden Goose grant (1001/PFIZIK/811012). CSY also thanks USM for the award of a USM Fellowship.
References
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N-heterocyclic carbene (NHC) ligands have enjoyed wide applicability as ligands for transition and main group metals since the first crystalline free carbene were isolated in 1991 by Arduengo and co-workers (Arduengo et al., 1991). They display rich coordination chemistry and are able to form stable complexes with a large number of transition metals in both high and low oxidation states (Papini et al., 2008). The complexes are widely used in catalysis and are useful in medicinal science applications (Meyer et al., 2009; Barnard et al., 2004; Lin & Vasam, 2007). These compounds show unusually high thermal stability and nucleophilic behavior, in part due to the analogy of N-heterocyclic carbenes with strong Lewis-basic phosphines. NHCs are also cheap, non-toxic and easily prepared as an azolium salt precursor (Papini et al., 2008).
The asymmetric unit of the title compound consists of half of the N-heterocyclic carbene dication and one hexafluorophosphate anion (Fig. 1). The dication lies across a crystallograpic inversion center. The geometrical parameters are comparable to its related structure (Washeel et al., 2010). The imidazole ring (N1–C5–N2–C7–C6) is planar with a maximum deviation of 0.003 (1) Å for atom C6 and is twisted away from the central benzene ring making a dihedral angle of 76.23 (6)°. The hexafluorophosphate anions linked the molecules into a three-dimensional network via intermolecular C—H···F hydrogen bonds (Fig. 2, Table 1). Short intermolecular F1···C5 and F1···C7 of 2.8636 (12) and 2.8798 (13) Å contacts are observed. A weak C–H···π interaction further stabilizes the crystal structure (Table 1).