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Acta Crystallographica Section E: Crystallographic Communications logoLink to Acta Crystallographica Section E: Crystallographic Communications
. 2026 Sep 11;82(Pt 10):1170–1174. doi: 10.1107/S2056989026009229

2,2′-(Ethane-1,2-di­yl)bis­[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexa­hydrate

Olga Yu Vassilyeva a,*, Vladimir N Kokozay a, Evgeny Goreshnik b
Editor: J Reibenspiesc
PMCID: PMC13638009  PMID: 42835851

The title compound crystallizes as a two-component twin in space group P21/n with Z′ = 1, exhibiting hydrogen-bonding corrugated layers of chloride ions and water mol­ecules that run approximately along the diagonal plane of the cell between columns of the stacked dications.

Keywords: crystal structure, twin, ethyl­enedi­amine, 2-pyridine­carbaldehyde, cyclo­condensation

Abstract

The title compound, C26H22N62+·2Cl−·6H2O, crystallizes in the monoclinic space group P21/n with one mol­ecule in the asymmetric unit. Structure determination at 150 K from a two-component twin crystal reveals the non-symmetrical n-shaped dication, where two pyridine–imidazole fused cores bearing pendant pyridyl rings are linked by an ethyl­ene bridge. The fused five- and six-membered rings are almost coplanar with the largest deviation from the mean plane being 0.019 Å for a nitro­gen atom of one of the rings. The pendant pyridyl groups are twisted by 42.14 (11) and 46.47 (11)° with respect to the planes of the adjacent imidazo[1,5-a]pyridinium cores. In the crystal, the dications stacked along the b-axis direction are linked by π–π inter­actions that possibly stabilize the n-type structure in the solid state. The chloride anions and water mol­ecules form R24(8), R55(12), R66(12) and R811(22) ring motifs through O—H⋯O/Cl hydrogen bonds, building corrugated layers that run between columns of the stacked organic dications.

1. Chemical context

Versatile optoelectronic properties, structural richness, and low temperature solution processability make organic–inorganic hybrid compounds based on metal halides an appealing alternative to conventional photovoltaic devices that utilize crystalline silicon solar cells (Zhu et al., 2022 ▸). Hybrid halometalates have been also actively researched for other applications as promising materials for light-emitting diodes (LEDs), semiconductor optical amplifiers, X-ray detectors, and lasers (Arya et al., 2024 ▸; You et al., 2023 ▸). The choice of appropriate organic cation is crucial to the structural consolidation and performance of the organic–inorganic hybrid system (Kucheriv et al., 2025 ▸).

Recently, we have developed a convenient synthetic technique to prepare hybrid salts consisting of functionalized imidazo[1,5-a]pyridinium cations and halometalate anions (Vassilyeva et al., 2020 ▸, 2023 ▸). The fused nitro­gen-containing bicyclic systems, imidazo[1,5-a]pyridines, are valuable in many research areas including materials science and pharmaceuticals (Esken et al., 2025 ▸; Gopathi et al., 2025 ▸). They exhibit intense fluorescence and high quantum yield (Volpi, 2022 ▸; Vasylets et al., 2026 ▸). In the developed synthetic procedure, the cation is produced in the inter­action between equimolar amounts of amine, formaldehyde (FA) and 2-pyridine­carbaldehyde (2-PCA) in aqueous solution and is used without isolation (Vassilyeva et al., 2020 ▸, 2021 ▸, 2023 ▸). The cyclo­condensation is catalysed by acid introduced as an adduct of the amine. The preformed cations synthesized with use of methyl­amine or ethano­lamine hydro­chlorides easily formed organic–inorganic hybrid compounds with metal halides (M = Mn, Co, Fe, Ni, Cu, Zn, Cd, Pb, Sn; Hal = Cl, Br, I). A similar outcome was expected for PdCl2, which willingly produces organic–inorganic hybrid salts based on the square-planar [PdCl4]2– anion (Salah et al., 2023 ▸). The replacement of the amine with ethyl­enedi­amine (En) in the reaction with PdCl2 using the molar ratio 2-PCA:FA:En·2HCl = 4:4:1 led to the isolation of the unexpected organic chloride salt with a novel imidazo[1,5-a]pyridinium-based dication as a minor product, whose identity was established crystallographically. We can speculate that the intrinsic catalytic activity of Pd2+ cations was responsible for its formation. Herein, we report the synthesis and crystal structure of [L]Cl2·6H2O (I), where [L]2+is 2,2′-(ethane-1,2-di­yl)bis­(3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium) dication, which crystallizes as a two-component twin.1.

2. Structural commentary

Monoclinic crystals of [L]Cl2·6H2O, which crystallize in the space group P21/n, contain discrete organic cations, chloride anions and water mol­ecules of crystallization (Fig. 1 ▸). In the n-shaped dication, two pyridine–imidazole fused cores bearing pendant pyridyl rings are linked by an ethyl­ene bridge. The pyridinium rings in the flattened fused moieties have expected bond distances; the bond lengths in the imidazolium entities fall in the range 1.342 (3)–1.407 (3) Å (Table 1 ▸). The fused five- and six-membered rings are almost coplanar, with the largest deviation from the mean plane being 0.019 Å (N5). The pendant pyridyl rings are twisted by 42.14 (11) (N1) and 46.47 (11)° (N6) with respect to the planes of the adjacent imidazo[1,5-a]pyridinium cores. The geometric parameters of the 3-(pyridin-2-yl)-imidazo[1,5-a]pyridinium moieties in the dication are similar to those found in related structures [Cambridge Structural Database (CSD) refcodes HUMCUP (Buvaylo et al., 2015 ▸) and GOSYUL (Vassilyeva et al., 2021 ▸)].

Figure 1.

Figure 1

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Mol­ecular structure of the title mol­ecular salt, with the atom labelling and displacement ellipsoids drawn at the 50% probability level.

Table 1. Selected bond lengths (Å).

N1—C1 1.342 (4) C4—C5 1.378 (4)
N1—C5 1.352 (3) C5—C6 1.477 (4)
N2—C6 1.342 (3) C7—C8 1.340 (4)
N2—C7 1.392 (3) C8—C9 1.423 (4)
N2—C11 1.407 (3) C9—C10 1.355 (4)
N3—C6 1.351 (3) C10—C11 1.411 (4)
N3—C12 1.361 (3) C11—C12 1.360 (4)
N3—C13 1.479 (3) C13—C14 1.505 (4)
N4—C14 1.464 (3) C15—C22 1.475 (4)
N4—C15 1.352 (3) C16—C17 1.340 (4)
N4—C21 1.364 (3) C17—C18 1.425 (4)
N5—C15 1.345 (3) C18—C19 1.342 (4)
N5—C16 1.395 (3) C19—C20 1.416 (4)
N5—C20 1.397 (3) C20—C21 1.363 (4)
N6—C22 1.346 (3) C22—C23 1.377 (4)
N6—C26 1.334 (3) C23—C24 1.382 (4)
C1—C2 1.380 (4) C24—C25 1.368 (4)
C2—C3 1.366 (4) C25—C26 1.372 (4)
C3—C4 1.396 (4)    
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3. Supra­molecular features

In the crystal, the dications are arranged in stacks aligned along the b-axis direction (Fig. 2 ▸). In a stack, L2+ cations are disposed in an anti­parallel fashion being linked through two types of stacking contacts. Those involve π–π inter­actions between pendant pyridyl groups and between the six-membered rings of the fused cores from adjacent organic moieties with the centroid⋯centroid distances of 4.043 (2) and 3.522 (2) Å, respectively (Fig. 3 ▸). The aromatic stacking is possibly important in the stabilization of the n-type structure of the dication in the solid state.

Figure 2.

Figure 2

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Crystal packing of (I), viewed along the b axis, showing stacks of organic dications between hydrogen-bonding corrugated layers formed by chloride anions and water mol­ecules. Hydrogen bonds are shown in blue.

Figure 3.

Figure 3

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Aromatic stacking of the dications in (I), viewed along the c axis.

The chloride ions and water mol­ecules are involved in the O—H⋯O/Cl inter­actions (Table 2 ▸), forming a hydrogen-bonding corrugated layer that runs approximately along the diagonal plane of the monoclinic cell containing the b axis, between columns of the stacked dications (Figs. 2 ▸ and 4 ▸). Using graph-set notation, there are several different hydrogen-bonding ring motifs: Inline graphic(8) (two water mol­ecules and two chlorides), Inline graphic(12) (five waters and a chloride), Inline graphic(12) (six waters), Inline graphic(22) (eight waters and three chlorides) (Fig. 5 ▸).

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1—H1A⋯O5 0.87 1.89 2.754 (3) 170
O2—H2A⋯O1 0.87 2.04 2.891 (4) 164
O2—H2B⋯O6 0.87 1.90 2.739 (3) 161
O3—H3A⋯Cl2i 0.87 2.26 3.119 (2) 169
O3—H3B⋯O2 0.87 1.88 2.737 (4) 169
O5—H5A⋯O4 0.87 1.90 2.758 (3) 169
O5—H5B⋯Cl1ii 0.87 2.25 3.117 (2) 176
O6—H6A⋯O3i 0.87 1.84 2.705 (3) 175
O6—H6B⋯Cl1 0.87 2.21 3.081 (2) 175
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Symmetry codes: (i) Inline graphic; (ii) Inline graphic.

Figure 4.

Figure 4

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Fragment of the hydrogen-bonding layer in (I), involving chloride anions and water mol­ecules and propagating approximately along the diagonal plane of the monoclinic cell containing the b axis (see Table 2 ▸ for details).

Figure 5.

Figure 5

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View of the Inline graphic(8), Inline graphic(12), Inline graphic(12) and Inline graphic(22) graph-set motifs forming closed rings through O—H⋯O/Cl hydrogen bonds between chloride anions and water mol­ecules in (I).

4. Database survey

120 structures of compounds featuring the 3-(pyridin-2-yl)imidazo[1,5-a]pyridine fragment are found in the CSD (Version 5.45, update Mar 2026; Groom et al., 2016 ▸) including the structure of neutral 3-(pyridin-2-yl)imidazo[1,5-a]pyridine itself (PRIMPY; Golič et al., 1980 ▸). Unlike compound (I), the mol­ecule of the latter as a whole is planar with the largest deviation from the mean plane of 0.06 Å for the pendant pyridyl group N atom (PRIMPY02; Tian et al., 2026 ▸). PRIMPY and its derivatives as ligands create a favourable coordination environment for cation binding through the pyridyl and imidazo ring nitro­gens giving rise to a variety of metal complexes. For example, in chloro-bis­(3-(pyridin-2-yl)imidazo[1,5-a]pyridine)­copper(II) chloride ethanol solvate (ELILOD; Carson et al., 2021 ▸), the ligands retain planarity upon coordination.

Functionalization of 3-(pyridin-2-yl)imidazo[1,5-a]pyridine at the imidazo ring nitro­gen turns the neutral mol­ecule into organic cation thus encouraging formation of organic–inorganic halometalate salts. 14 crystal structures from our research span hybrid halometalates, metal complexes (LOJFUO and HOMZER, respectively; Vassilyeva et al., 2019a ▸) and organic salts (HOMZER; Vassilyeva et al., 2019b ▸) with the monopositive 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium cation, which can be seen as half of L2+. The structural configurations of the monopositive cation with a flattened fused core are similar to that of L2+ with the degree of twist between the pendant pyridyl rings and the planes of the remainder of the cation as large as 85.30 (3)° (HUMCUP; Buvaylo et al., 2015 ▸).

5. Synthesis and crystallization

Formaldehyde solution was prepared by dissolving paraform (0.13 g, 4.5 mmol) in 10 ml boiling deionized water in a 50 ml conical flask. After cooling at r.t., solid En·2HCl (0.26 g, 1.2 mmol) was added to the FA solution, which was stirred at r.t. for half an hour and then filtered. In a week, 2-PCA (0.38 ml, 4 mmol) was introduced into the flask followed by subsequent dropwise addition of PdCl2 (0.35 g, 2 mmol) dissolved in CH3CN (5 ml). The brownish solution was kept stirring for 1 h, then filtered and left open to stand at r.t. The inseparable mixture of a dark residue and light yellow crystals precipitated over several weeks. The precipitate was filtered off, washed with iPrOH and finally dried in air. Yellow needles of (I) suitable for X-ray crystallography that constituted a minor product were withdrawn manually.

6. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3 ▸. The structure was refined as a two-component twin with a ratio of 0.7078 (12):0.2922 (12). Component 2 is rotated by −179.9853° around [0.71 −0.00 −0.71] (reciprocal) or [0.99 0.00 −0.14] (direct). H atoms of the water mol­ecules were located in a difference-Fourier map and refined as free rotating groups. Anisotropic displacement parameters were employed for the non-hydrogen atoms. The H atoms attached to carbon atoms were added at calculated positions and refined as riding with isotropic displacement parameters based on those of the parent atom [C—H = 0.95 Å, Uiso(H) = 1.2Ueq(C) for CH; C—H = 0.99 Å, Uiso(H) = 1.5Ueq(C) for CH2].

Table 3. Experimental details.

Crystal data
Chemical formula C26H22N62+·2(Cl−)·6(H2O)
M r 597.49
Crystal system, space group Monoclinic, P21/n
Temperature (K) 150
a, b, c (Å) 9.0061 (7), 15.1053 (10), 21.2487 (14)
β (°) 96.752 (7)
V (Å3) 2870.6 (3)
Z 4
Radiation type Mo Kα
μ (mm−1) 0.28
Crystal size (mm) 0.38 × 0.09 × 0.05
 
Data collection
Diffractometer New Gemini, Dual, Cu at home/near, Atlas
Absorption correction Analytical (CrysAlis PRO; Rigaku OD, 2026 ▸)
Tmin, Tmax 0.933, 0.980
No. of measured, independent and observed [I > 2σ(I)] reflections 6542, 6542, 3396
R int ?
(sin θ/λ)max (Å−1) 0.678
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.091, 0.86
No. of reflections 6542
No. of parameters 380
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.27, −0.34
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Computer programs: CrysAlis PRO (Rigaku OD, 2026 ▸), SHELXT (Sheldrick, 2015a ▸), SHELXL2016/6 (Sheldrick, 2015b ▸), OLEX2 (Dolomanov et al., 2009 ▸) and Mercury (Macrae et al., 2020 ▸).

Supplementary Material

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989026009229/jy2076sup1.cif

e-82-01170-sup1.cif (352KB, cif)

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989026009229/jy2076Isup2.hkl

e-82-01170-Isup2.hkl (520KB, hkl)
e-82-01170-Isup3.cml (10.6KB, cml)

Supporting information file. DOI: 10.1107/S2056989026009229/jy2076Isup3.cml

CCDC reference: 2585211

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors are grateful to the FAIRE programme provided by the Cambridge Crystallographic Data Centre (CCDC) for the opportunity to use the Cambridge Structural Database (CSD) and associated software.

supplementary crystallographic information

2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Crystal data

C26H22N62+·2(Cl−)·6(H2O) F(000) = 1256
Mr = 597.49 Dx = 1.382 Mg m−3
Monoclinic, P21/n Mo Kα radiation, λ = 0.71073 Å
a = 9.0061 (7) Å Cell parameters from 3978 reflections
b = 15.1053 (10) Å θ = 2.9–27.3°
c = 21.2487 (14) Å µ = 0.28 mm−1
β = 96.752 (7)° T = 150 K
V = 2870.6 (3) Å3 Needle, yellow
Z = 4 0.38 × 0.09 × 0.05 mm
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Data collection

New Gemini, Dual, Cu at home/near, Atlas diffractometer 6542 measured reflections
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source 6542 independent reflections
Graphite monochromator 3396 reflections with I > 2σ(I)
Detector resolution: 10.6426 pixels mm-1 θmax = 28.8°, θmin = 2.4°
ω scans h = −9→12
Absorption correction: analytical (CrysAlisPro; Rigaku OD, 2026) k = −20→20
Tmin = 0.933, Tmax = 0.980 l = −27→27
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Refinement

Refinement on F2 Primary atom site location: dual
Least-squares matrix: full Hydrogen site location: mixed
R[F2 > 2σ(F2)] = 0.051 H-atom parameters constrained
wR(F2) = 0.091 w = 1/[σ2(Fo2) + (0.0354P)2] where P = (Fo2 + 2Fc2)/3
S = 0.86 (Δ/σ)max < 0.001
6542 reflections Δρmax = 0.27 e Å−3
380 parameters Δρmin = −0.34 e Å−3
0 restraints
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Special details

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. Refined as a 2-component twin.
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2)

x y z Uiso*/Ueq
Cl1 0.34159 (8) 0.44925 (5) 0.27864 (3) 0.02028 (19)
Cl2 0.34229 (8) 0.12488 (5) 0.45445 (4) 0.02505 (19)
O1 0.3969 (2) 0.69367 (14) 0.30924 (12) 0.0397 (7)
H1A 0.391339 0.751196 0.309624 0.060*
O2 0.3441 (3) 0.65200 (15) 0.43752 (12) 0.0498 (7)
H2A 0.378637 0.665517 0.402141 0.075*
H2B 0.341652 0.594725 0.441537 0.075*
O3 0.6113 (3) 0.67544 (13) 0.51139 (11) 0.0349 (6)
H3A 0.631277 0.728534 0.525820 0.052*
H3B 0.522942 0.674898 0.489763 0.052*
O4 0.3695 (3) 0.91568 (14) 0.44330 (11) 0.0399 (6)
H4A 0.445418 0.902545 0.470926 0.060*
H4B 0.361142 0.972962 0.445853 0.060*
O5 0.4114 (2) 0.87522 (14) 0.32004 (10) 0.0254 (5)
H5A 0.393442 0.894352 0.357044 0.038*
H5B 0.341090 0.898619 0.293589 0.038*
O6 0.3141 (2) 0.47281 (13) 0.42080 (10) 0.0274 (5)
H6A 0.343403 0.426310 0.443087 0.041*
H6B 0.326415 0.463805 0.381280 0.041*
N1 0.7510 (2) 0.75581 (14) 0.31869 (11) 0.0137 (6)
N2 0.7252 (2) 0.79911 (14) 0.18463 (11) 0.0117 (5)
N3 0.9513 (2) 0.75222 (14) 0.18391 (11) 0.0136 (6)
N4 1.0080 (2) 0.58519 (14) 0.25551 (10) 0.0115 (5)
N5 0.8298 (2) 0.55106 (14) 0.31092 (10) 0.0102 (5)
N6 0.6229 (2) 0.59715 (14) 0.19762 (11) 0.0154 (6)
C1 0.7612 (3) 0.75961 (18) 0.38213 (15) 0.0208 (7)
H1 0.677703 0.740553 0.402076 0.025*
C2 0.8859 (3) 0.78960 (19) 0.42009 (14) 0.0211 (8)
H2 0.888213 0.789370 0.464908 0.025*
C3 1.0059 (3) 0.81963 (18) 0.39254 (14) 0.0215 (8)
H3 1.093105 0.840312 0.417761 0.026*
C4 0.9977 (3) 0.81926 (18) 0.32654 (13) 0.0173 (7)
H4 1.077720 0.841562 0.305784 0.021*
C5 0.8707 (3) 0.78580 (17) 0.29215 (13) 0.0116 (7)
C6 0.8515 (3) 0.78033 (17) 0.22228 (13) 0.0121 (7)
C7 0.5893 (3) 0.83128 (17) 0.20013 (14) 0.0161 (7)
H7 0.575635 0.843549 0.242923 0.019*
C8 0.4782 (3) 0.84457 (18) 0.15337 (14) 0.0212 (7)
H8 0.385170 0.866297 0.163785 0.025*
C9 0.4944 (3) 0.82734 (19) 0.08866 (15) 0.0234 (8)
H9 0.413001 0.837278 0.056747 0.028*
C10 0.6264 (3) 0.79669 (19) 0.07286 (14) 0.0214 (8)
H10 0.638820 0.785341 0.029810 0.026*
C11 0.7453 (3) 0.78182 (18) 0.12115 (13) 0.0150 (7)
C12 0.8885 (3) 0.75273 (17) 0.12243 (14) 0.0150 (7)
H12 0.936291 0.735764 0.086739 0.018*
C13 1.1011 (3) 0.71386 (18) 0.20266 (14) 0.0162 (7)
H13A 1.141404 0.736686 0.244920 0.019*
H13B 1.169780 0.732209 0.171945 0.019*
C14 1.0936 (3) 0.61436 (17) 0.20481 (13) 0.0134 (6)
H14A 1.045755 0.591735 0.163619 0.016*
H14B 1.196154 0.589822 0.212102 0.016*
C15 0.8620 (3) 0.56256 (16) 0.25123 (13) 0.0101 (6)
C16 0.6964 (3) 0.52366 (17) 0.33213 (14) 0.0149 (7)
H16 0.610915 0.510540 0.303019 0.018*
C17 0.6923 (3) 0.51638 (18) 0.39477 (14) 0.0212 (7)
H17 0.601920 0.498198 0.409892 0.025*
C18 0.8192 (3) 0.53505 (18) 0.43937 (14) 0.0200 (7)
H18 0.811986 0.530007 0.483475 0.024*
C19 0.9489 (3) 0.55973 (18) 0.41937 (13) 0.0169 (7)
H19 1.033991 0.571571 0.448994 0.020*
C20 0.9570 (3) 0.56788 (17) 0.35347 (13) 0.0129 (7)
C21 1.0676 (3) 0.58904 (17) 0.31752 (13) 0.0132 (7)
H21 1.167919 0.603788 0.332841 0.016*
C22 0.7543 (3) 0.55631 (17) 0.19346 (12) 0.0115 (6)
C23 0.7883 (3) 0.51304 (17) 0.13998 (13) 0.0159 (7)
H23 0.881120 0.483198 0.139762 0.019*
C24 0.6847 (3) 0.51395 (19) 0.08661 (14) 0.0230 (8)
H24 0.705556 0.486108 0.048541 0.028*
C25 0.5512 (3) 0.5559 (2) 0.08991 (14) 0.0253 (8)
H25 0.478077 0.558064 0.053876 0.030*
C26 0.5239 (3) 0.59480 (18) 0.14577 (14) 0.0197 (7)
H26 0.429119 0.621606 0.147604 0.024*
H1B 0.494800 0.679000 0.299700 0.030*
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23
Cl1 0.0174 (4) 0.0227 (4) 0.0209 (4) −0.0004 (3) 0.0030 (3) −0.0044 (3)
Cl2 0.0263 (5) 0.0283 (4) 0.0213 (4) −0.0060 (4) 0.0059 (4) −0.0017 (4)
O1 0.0234 (14) 0.0268 (13) 0.0667 (18) 0.0002 (11) −0.0040 (13) 0.0101 (13)
O2 0.0586 (18) 0.0339 (15) 0.0542 (18) −0.0039 (14) −0.0043 (15) 0.0069 (12)
O3 0.0443 (17) 0.0280 (13) 0.0326 (15) 0.0009 (12) 0.0061 (12) −0.0006 (11)
O4 0.0471 (18) 0.0340 (14) 0.0351 (15) 0.0009 (12) −0.0100 (13) −0.0082 (11)
O5 0.0195 (13) 0.0286 (12) 0.0269 (13) 0.0043 (10) −0.0021 (10) −0.0017 (11)
O6 0.0337 (14) 0.0309 (13) 0.0184 (12) −0.0023 (11) 0.0059 (11) 0.0035 (10)
N1 0.0145 (15) 0.0156 (13) 0.0127 (14) 0.0017 (10) 0.0081 (12) 0.0011 (11)
N2 0.0109 (14) 0.0112 (13) 0.0139 (14) 0.0023 (10) 0.0052 (12) 0.0012 (11)
N3 0.0104 (14) 0.0138 (13) 0.0176 (15) 0.0028 (10) 0.0061 (12) 0.0018 (11)
N4 0.0087 (14) 0.0147 (13) 0.0114 (13) 0.0034 (10) 0.0023 (11) 0.0011 (10)
N5 0.0079 (13) 0.0127 (12) 0.0103 (13) −0.0016 (11) 0.0020 (11) 0.0000 (11)
N6 0.0088 (14) 0.0169 (13) 0.0208 (14) 0.0005 (11) 0.0025 (11) −0.0003 (11)
C1 0.0193 (19) 0.0221 (18) 0.0225 (19) 0.0014 (14) 0.0089 (16) 0.0002 (14)
C2 0.026 (2) 0.0214 (18) 0.0174 (18) 0.0023 (15) 0.0067 (16) −0.0010 (14)
C3 0.0220 (19) 0.0204 (18) 0.0219 (19) −0.0044 (14) 0.0020 (15) −0.0025 (14)
C4 0.0153 (18) 0.0197 (17) 0.0183 (18) −0.0031 (13) 0.0075 (14) 0.0012 (14)
C5 0.0103 (17) 0.0092 (14) 0.0161 (17) 0.0048 (12) 0.0044 (13) −0.0006 (13)
C6 0.0124 (17) 0.0076 (14) 0.0171 (17) −0.0015 (12) 0.0049 (14) 0.0016 (13)
C7 0.0107 (17) 0.0148 (16) 0.0248 (18) 0.0022 (13) 0.0110 (15) 0.0023 (14)
C8 0.0151 (18) 0.0177 (17) 0.0309 (19) 0.0050 (13) 0.0038 (16) 0.0054 (14)
C9 0.0200 (19) 0.0222 (18) 0.0264 (19) 0.0052 (14) −0.0039 (15) 0.0065 (15)
C10 0.028 (2) 0.0209 (18) 0.0159 (18) 0.0040 (15) 0.0059 (16) 0.0064 (14)
C11 0.0174 (18) 0.0147 (16) 0.0143 (17) 0.0017 (13) 0.0075 (14) 0.0040 (13)
C12 0.0140 (18) 0.0169 (17) 0.0146 (18) 0.0005 (13) 0.0043 (14) 0.0016 (13)
C13 0.0069 (17) 0.0240 (17) 0.0179 (17) 0.0013 (13) 0.0026 (13) 0.0036 (14)
C14 0.0049 (15) 0.0236 (17) 0.0120 (15) −0.0006 (13) 0.0021 (12) −0.0001 (14)
C15 0.0083 (16) 0.0077 (14) 0.0148 (16) 0.0022 (12) 0.0035 (13) 0.0005 (13)
C16 0.0092 (16) 0.0150 (15) 0.0215 (18) 0.0014 (13) 0.0052 (14) 0.0045 (13)
C17 0.0175 (18) 0.0211 (17) 0.028 (2) 0.0068 (14) 0.0169 (16) 0.0109 (15)
C18 0.0234 (19) 0.0227 (18) 0.0152 (17) 0.0096 (14) 0.0076 (15) 0.0060 (14)
C19 0.0203 (19) 0.0207 (17) 0.0095 (16) 0.0059 (14) 0.0007 (14) 0.0000 (13)
C20 0.0112 (17) 0.0128 (16) 0.0146 (16) 0.0051 (12) 0.0013 (13) 0.0009 (13)
C21 0.0080 (16) 0.0157 (16) 0.0144 (16) 0.0009 (12) −0.0045 (14) 0.0018 (12)
C22 0.0107 (16) 0.0087 (14) 0.0151 (16) −0.0024 (13) 0.0008 (13) 0.0015 (13)
C23 0.0102 (16) 0.0159 (16) 0.0215 (18) 0.0015 (13) 0.0020 (14) −0.0026 (14)
C24 0.027 (2) 0.0253 (18) 0.0159 (18) −0.0056 (15) −0.0002 (15) −0.0093 (14)
C25 0.023 (2) 0.0314 (19) 0.0185 (18) −0.0032 (16) −0.0101 (15) −0.0011 (16)
C26 0.0077 (16) 0.0232 (18) 0.0264 (19) −0.0035 (13) −0.0055 (14) 0.0035 (14)
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Geometric parameters (Å, º)

O1—H1A 0.8705 C5—C6 1.477 (4)
O1—H1B 0.954 (2) C7—H7 0.9500
O2—H2A 0.8710 C7—C8 1.340 (4)
O2—H2B 0.8699 C8—H8 0.9500
O3—H3A 0.8698 C8—C9 1.423 (4)
O3—H3B 0.8708 C9—H9 0.9500
O4—H4A 0.8702 C9—C10 1.355 (4)
O4—H4B 0.8707 C10—H10 0.9500
O5—H5A 0.8705 C10—C11 1.411 (4)
O5—H5B 0.8706 C11—C12 1.360 (4)
O6—H6A 0.8706 C12—H12 0.9500
O6—H6B 0.8707 C13—H13A 0.9900
N1—C1 1.342 (4) C13—H13B 0.9900
N1—C5 1.352 (3) C13—C14 1.505 (4)
N2—C6 1.342 (3) C14—H14A 0.9900
N2—C7 1.392 (3) C14—H14B 0.9900
N2—C11 1.407 (3) C15—C22 1.475 (4)
N3—C6 1.351 (3) C16—H16 0.9500
N3—C12 1.361 (3) C16—C17 1.340 (4)
N3—C13 1.479 (3) C17—H17 0.9500
N4—C14 1.464 (3) C17—C18 1.425 (4)
N4—C15 1.352 (3) C18—H18 0.9500
N4—C21 1.364 (3) C18—C19 1.342 (4)
N5—C15 1.345 (3) C19—H19 0.9500
N5—C16 1.395 (3) C19—C20 1.416 (4)
N5—C20 1.397 (3) C20—C21 1.363 (4)
N6—C22 1.346 (3) C21—H21 0.9500
N6—C26 1.334 (3) C22—C23 1.377 (4)
C1—H1 0.9500 C23—H23 0.9500
C1—C2 1.380 (4) C23—C24 1.382 (4)
C2—H2 0.9500 C24—H24 0.9500
C2—C3 1.366 (4) C24—C25 1.368 (4)
C3—H3 0.9500 C25—H25 0.9500
C3—C4 1.396 (4) C25—C26 1.372 (4)
C4—H4 0.9500 C26—H26 0.9500
C4—C5 1.378 (4)
H1A—O1—H1B 106.8 C12—C11—C10 134.7 (3)
H2A—O2—H2B 109.5 N3—C12—H12 126.1
H3A—O3—H3B 109.5 C11—C12—N3 107.9 (3)
H4A—O4—H4B 104.6 C11—C12—H12 126.1
H5A—O5—H5B 104.5 N3—C13—H13A 109.5
H6A—O6—H6B 109.5 N3—C13—H13B 109.5
C1—N1—C5 116.2 (2) N3—C13—C14 110.9 (2)
C6—N2—C7 129.8 (2) H13A—C13—H13B 108.0
C6—N2—C11 109.7 (2) C14—C13—H13A 109.5
C7—N2—C11 120.5 (2) C14—C13—H13B 109.5
C6—N3—C12 110.3 (2) N4—C14—C13 110.6 (2)
C6—N3—C13 127.7 (2) N4—C14—H14A 109.5
C12—N3—C13 121.6 (2) N4—C14—H14B 109.5
C15—N4—C14 128.2 (2) C13—C14—H14A 109.5
C15—N4—C21 110.2 (2) C13—C14—H14B 109.5
C21—N4—C14 121.1 (2) H14A—C14—H14B 108.1
C15—N5—C16 129.2 (2) N4—C15—C22 127.7 (2)
C15—N5—C20 109.6 (2) N5—C15—N4 106.6 (2)
C16—N5—C20 121.1 (2) N5—C15—C22 125.7 (2)
C26—N6—C22 116.1 (2) N5—C16—H16 121.0
N1—C1—H1 118.1 C17—C16—N5 118.1 (3)
N1—C1—C2 123.8 (3) C17—C16—H16 121.0
C2—C1—H1 118.1 C16—C17—H17 119.0
C1—C2—H2 120.4 C16—C17—C18 122.1 (3)
C3—C2—C1 119.3 (3) C18—C17—H17 119.0
C3—C2—H2 120.4 C17—C18—H18 119.9
C2—C3—H3 120.7 C19—C18—C17 120.3 (3)
C2—C3—C4 118.6 (3) C19—C18—H18 119.9
C4—C3—H3 120.7 C18—C19—H19 120.5
C3—C4—H4 120.8 C18—C19—C20 119.1 (3)
C5—C4—C3 118.5 (3) C20—C19—H19 120.5
C5—C4—H4 120.8 N5—C20—C19 119.4 (2)
N1—C5—C4 123.6 (3) C21—C20—N5 106.1 (2)
N1—C5—C6 113.3 (2) C21—C20—C19 134.5 (3)
C4—C5—C6 123.1 (3) N4—C21—H21 126.2
N2—C6—N3 106.5 (2) C20—C21—N4 107.5 (2)
N2—C6—C5 125.4 (2) C20—C21—H21 126.2
N3—C6—C5 128.1 (3) N6—C22—C15 114.4 (2)
N2—C7—H7 120.7 N6—C22—C23 123.7 (3)
C8—C7—N2 118.5 (3) C23—C22—C15 121.9 (2)
C8—C7—H7 120.7 C22—C23—H23 120.7
C7—C8—H8 118.8 C22—C23—C24 118.6 (3)
C7—C8—C9 122.5 (3) C24—C23—H23 120.7
C9—C8—H8 118.8 C23—C24—H24 120.8
C8—C9—H9 120.2 C25—C24—C23 118.4 (3)
C10—C9—C8 119.6 (3) C25—C24—H24 120.8
C10—C9—H9 120.2 C24—C25—H25 120.3
C9—C10—H10 120.4 C24—C25—C26 119.4 (3)
C9—C10—C11 119.2 (3) C26—C25—H25 120.3
C11—C10—H10 120.4 N6—C26—C25 123.8 (3)
N2—C11—C10 119.7 (2) N6—C26—H26 118.1
C12—C11—N2 105.7 (2) C25—C26—H26 118.1
N1—C1—C2—C3 1.8 (4) C11—N2—C7—C8 0.6 (4)
N1—C5—C6—N2 40.3 (4) C12—N3—C6—N2 −0.3 (3)
N1—C5—C6—N3 −136.2 (3) C12—N3—C6—C5 176.8 (3)
N2—C7—C8—C9 −0.2 (4) C12—N3—C13—C14 −77.9 (3)
N2—C11—C12—N3 0.2 (3) C13—N3—C6—N2 −172.3 (2)
N3—C13—C14—N4 −66.3 (3) C13—N3—C6—C5 4.8 (4)
N4—C15—C22—N6 −132.1 (3) C13—N3—C12—C11 172.6 (2)
N4—C15—C22—C23 47.1 (4) C14—N4—C15—N5 −172.6 (2)
N5—C15—C22—N6 44.1 (4) C14—N4—C15—C22 4.2 (4)
N5—C15—C22—C23 −136.8 (3) C14—N4—C21—C20 172.9 (2)
N5—C16—C17—C18 −0.5 (4) C15—N4—C14—C13 96.2 (3)
N5—C20—C21—N4 0.2 (3) C15—N4—C21—C20 0.3 (3)
N6—C22—C23—C24 2.4 (4) C15—N5—C16—C17 179.4 (3)
C1—N1—C5—C4 −0.3 (4) C15—N5—C20—C19 −180.0 (2)
C1—N1—C5—C6 −179.6 (2) C15—N5—C20—C21 −0.6 (3)
C1—C2—C3—C4 0.3 (4) C15—C22—C23—C24 −176.6 (3)
C2—C3—C4—C5 −2.2 (4) C16—N5—C15—N4 −176.9 (2)
C3—C4—C5—N1 2.3 (4) C16—N5—C15—C22 6.3 (4)
C3—C4—C5—C6 −178.6 (3) C16—N5—C20—C19 −2.1 (4)
C4—C5—C6—N2 −138.9 (3) C16—N5—C20—C21 177.3 (2)
C4—C5—C6—N3 44.5 (4) C16—C17—C18—C19 −0.9 (4)
C5—N1—C1—C2 −1.7 (4) C17—C18—C19—C20 0.7 (4)
C6—N2—C7—C8 −179.8 (3) C18—C19—C20—N5 0.7 (4)
C6—N2—C11—C10 179.9 (2) C18—C19—C20—C21 −178.4 (3)
C6—N2—C11—C12 −0.4 (3) C19—C20—C21—N4 179.4 (3)
C6—N3—C12—C11 0.1 (3) C20—N5—C15—N4 0.8 (3)
C6—N3—C13—C14 93.3 (3) C20—N5—C15—C22 −176.0 (2)
C7—N2—C6—N3 −179.2 (2) C20—N5—C16—C17 1.9 (4)
C7—N2—C6—C5 3.6 (4) C21—N4—C14—C13 −74.9 (3)
C7—N2—C11—C10 −0.4 (4) C21—N4—C15—N5 −0.7 (3)
C7—N2—C11—C12 179.3 (2) C21—N4—C15—C22 176.0 (2)
C7—C8—C9—C10 −0.3 (4) C22—N6—C26—C25 −1.7 (4)
C8—C9—C10—C11 0.5 (4) C22—C23—C24—C25 −1.7 (4)
C9—C10—C11—N2 −0.1 (4) C23—C24—C25—C26 −0.6 (4)
C9—C10—C11—C12 −179.7 (3) C24—C25—C26—N6 2.4 (5)
C10—C11—C12—N3 179.8 (3) C26—N6—C22—C15 178.4 (2)
C11—N2—C6—N3 0.5 (3) C26—N6—C22—C23 −0.7 (4)
C11—N2—C6—C5 −176.7 (3)
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2,2'-(Ethane-1,2-diyl)bis[3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] dichloride hexahydrate . Hydrogen-bond geometry (Å, º)

D—H···A D—H H···A D···A D—H···A
O1—H1A···O5 0.87 1.89 2.754 (3) 170
O2—H2A···O1 0.87 2.04 2.891 (4) 164
O2—H2B···O6 0.87 1.90 2.739 (3) 161
O3—H3A···Cl2i 0.87 2.26 3.119 (2) 169
O3—H3B···O2 0.87 1.88 2.737 (4) 169
O5—H5A···O4 0.87 1.90 2.758 (3) 169
O5—H5B···Cl1ii 0.87 2.25 3.117 (2) 176
O6—H6A···O3i 0.87 1.84 2.705 (3) 175
O6—H6B···Cl1 0.87 2.21 3.081 (2) 175
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Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x+1/2, y+1/2, −z+1/2.

Funding Statement

Funding for this research was provided by: the Ministry of Education and Science of Ukraine (grant No. 26BF037-01 to O. Yu. Vassilyeva; grant No. 26BF037-04 to V. N. Kokozay).

References

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989026009229/jy2076sup1.cif

e-82-01170-sup1.cif (352KB, cif)

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989026009229/jy2076Isup2.hkl

e-82-01170-Isup2.hkl (520KB, hkl)
e-82-01170-Isup3.cml (10.6KB, cml)

Supporting information file. DOI: 10.1107/S2056989026009229/jy2076Isup3.cml

CCDC reference: 2585211

Additional supporting information: crystallographic information; 3D view; checkCIF report

Articles from Acta Crystallographica Section E: Crystallographic Communications are provided here courtesy of International Union of Crystallography

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