Polar hydrogen-bonded organic chains in 4,4′-bipyrazolium bromide and perchlorate monohydrates

4,4′-Bipyrazolium [or 4-(1H-pyrazol-4-yl)pyrazolium] bromide monohydrate, C₆H₇N₄⁺·Br⁻·H₂O, and 4,4′-bipyrazolium perchlorate monohydrate, C₆H₇N₄⁺·ClO₄⁻·H₂O, have closely related layered structures involving tight stacks of antiparallel N—H...N hydrogen-bonded polar bipyrazolium chains [N...N = 2.712 (3) and 2.742 (2) Å], which are crosslinked by hydrogen bonds with water mol­ecules and counter-anions.

S1. Comment

Pyrazole possesses self-complementary functionality and yields hydrogen-bonded polar chains when associated by `head-to-tail' NH···N hydrogen bonding (Foces-Foces et al., 2000). The doubled number of hydrogen-bond donor (NH) and acceptor (N) sites (2:2) of 4,4'-bipyrazole allows the incorporation of this polar motif into a planar hydrogen-bonded network (Boldog et al., 2001). However, the molecular symmetry of the 4,4'-bipyrazole molecule effects its situation across a centre of inversion and this eliminates any overall polarity of the hydrogen-bonding directions. Double protonation of 4,4'-bipyrazole yields centrosymmetric dications, which act as donors of four NH···X hydrogen bonds and which are unable to participate in self-association due to a lack of acceptor sites (Boldog, 2005). Unlike these cases, 4,4'-bipyrazolium monocations are inherently noncentrosymmetric and they retain both types of binding sites (NH and N), in a 3:1 ratio, allowing self-association and effective interchain interactions. Thus, singly protonated 4,4'-bipyrazole offers a special potential for the generation of polar hydrogen-bonded chains and their integration into an extended architecture. In this context, we have prepared two new salts of 4,4'-bipyrazole, (I) and (II), and present their structures here.

The structural results reveal the close resemblance of the crystalline salts (I) and (II). The bipyrazolium monocations have a nearly planar structure. The dihedral angles between the mean planes of the two heterocyclic fragments are 3.5 (1)° in (I) and 8.7 (1)° in (II) (Figs. 1 and 2). Protonation of the pyrazole ring results in the equivalence of atoms N1 and N2, and the corresponding pairs of bonds, C1—N1 and C3—N2, and C1—C2 and C2—C3, are actually uniform in length, while bond C6—N4 (N) remains ca 0.02 Å shorter than C4—N3 (NH). This reflects the greater delocalization of π-electron density within the frame of the pyrazolium moiety compared with the neutral pyrazole fragment. The N3—N4 bond lengths for the neutral pyrazole fragments are the same as for 4,4'-bipyrazole [1.345 (2) Å; Boldog et al., 2001] or its complexes with metal ions [1.341 (2)–1.347 (2) Å; Boldog et al., 2002], while the N1—N2 bonds for the protonated fragments are somewhat shortened and are comparable with the parameter for 4,4'-bipyrazolium diperchlorate [1.328 (3) Å; Boldog, 2005]. A similar result may be found from a comparison of the molecular geometries of pyrazole (la Cour & Rasmussen, 1973) and the pyrazolium cation (Ishida & Kashino, 2001) (N—N 1.343 and 1.335 Å, respectively).

The bipyrazolium monocations in (I) and (II) associate in a uniform fashion, yielding polar chains with relatively strong hydrogen bonds [N···N 2.712 (3) and 2.742 (2) Å, respectively], employing the only acceptor sites, N4, and the N2—H2 donor sites trans to them (Figs. 3 and 4). Owing to the cationic nature of the donor sites, these NH···N interactions are appreciably stronger than those observed for neutral species [2.912 (3) Å for pyrazole (la Cour & Rasmussen, 1973) and 2.886 (2) Å for 4,4'-bipyrazole (Boldog et al., 2001)].

Two bipyrazolium cations, related by inversion [symmetry codes: (1 − x, −y, 1 − z) for (I) and (−x, 1 − y, 1 − z) for (II)], afford tight π–π stacking, in which the interaction occurs between pairs of cationic (A) and neutral (B) pyrazole rings. Such a mode of stacking dictates antiparallel alignment of the chains. Within the hydrogen-bonded layers (Figs. 3 and 4), the geometric parameters of π–π interactions (Janiak, 2000) are similar for (I) and (II) (Tables 3 and 6). For (I), both intra- and interlayer π–π stacking follow the A/B mode and are actually uniform in their geometry, while for (II), the interlayer interactions are supported by B/B (−x, 2 − y, 1 − z) and A/A (1 − x, 1 − y, 1 − z) stacking modes.

The hydrogen-bonded chains retain two NH functions per bipyrazole block and donate a set of NH···O and NH···Br hydrogen bonds to finite hydrogen-bonded anion–water ensembles [(H₂O)₂(X)₂]²⁻ [X is Br in (I) or ClO₄ in (II)]. These lie across centres of inversion and unite pairs of antiparallel bipyrazolium chains into layers. Such centrosymmetric 2:2 anion–water aggregates have also been observed for acetylcarnitine hydrochloride monohydrate (Destro & Heyda, 1977). The water molecules tend to accept bonds from the cationic pyrazole fragment, while the anions are bound to the neutral pyrazole site (Tables 2 and 4). Hydrogen bonds of the type NH···Br in (I) [3.312 (2) Å] are only slightly weaker than the hydrogen bonding observed in pyrazolium bromides (3.17–3.22 Å; Foces-Foces et al., 1997).

A number of directional CH···O(X) interactions observed in (I) and (II) could be attributed to a weaker hydrogen bond (Desiraju & Steiner, 1999). The protonation evidently enhances the CH acidity of the pyrazole ring and, as a result, the CH···O(X) interactions donated by the cationic pyrazole fragment are appreciably shorter. Thus, in (II) the cationic pyrazolium fragment supports three weak CH···O bonds [C···O 3.267 (3)–3.386 (3) Å], while the shortest CH···O contact donated by the neutral pyrazole fragment is longer [3.502 (3) Å]. Similar directional CH···O hydrogen bonding [C···O 3.201 (3) Å] also occurs for the pyrazolium cation in the salt with 2,5-dichloro-3,6-dioxy-1,4-benzoquinone (Ishida & Kashino, 2001). The shortest C···Br separation in (I) is also observed for the cationic pyrazolium fragment (Table 2) and is comparable with the typical CH···Br bond in acetylenes (3.72 Å; Steiner, 1998).

Thus, the 4,4'-bipyrazolium monocations of (I) and (II) produce polar hydrogen-bonded chains by direct association. The mode of the intercation stacking, however, effects an antiparallel alignment of the chains and this mitigates against bulk polarity of the structure. We intend to investigate a series of related systems in order to resolve this problem.

S2. Experimental

4,4'-Bipyrazole was prepared by condensation of 1,1,2,2-ethanetetraaldehyde and hydrazine (Trofimenko, 1964). Recrystallization of the compound from hot 10% aqueous HBr or hot 10% aqueous HClO₄ afforded large colourless prisms of salts (I) and (II), respectively.

S3. Refinement

The structures were solved by direct methods. All H atoms were located from difference maps and then refined as riding, with O—H distances constrained to 0.85 Å, N—H distances constrained to 0.90 Å and C—H distances constrained to 0.96 Å, and with U_iso(H) = 1.2U_eq(parent atom).

Computing details

For both compounds, data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. The structure of (I), showing the atom- and ring-labelling schemes. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. Dashed lines indicate hydrogen bonds.
	Fig. 2. The structure of (II), showing the atom- and ring-labelling schemes. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. Dashed lines indicate hydrogen bonds.
	Fig. 3. A perspective view of the structure of (I), showing NH and OH hydrogen bonds as dashed lines. N atoms are shaded grey. Note the antiparallel packing of the polar bipyrazolium chains. [Symmetry codes: (i) x, 1 + y, z; (iii) 1 − x, 1 − y, −z.]
	Fig. 4. A perspective view of the structure of (II) showing NH and OH hydrogen bonds as dashed lines. N atoms are shaded grey. Note the antiparallel packing of the polar bipyrazolium chains. [Symmetry codes: (i) 1 + x, y − 1, z; (ii) −x, 1 − y, 1 − z; (iii) 2 − x, −y, −z.]

(I) 4-(1H-pyrazol-4-yl)pyrazolium bromide monohydrate

Crystal data

C6H7N4^+·Br^−·H2O	Z = 2
Mr = 233.08	F(000) = 232
Triclinic, P1	Dx = 1.677 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.1352 (11) Å	Cell parameters from 22 reflections
b = 8.505 (2) Å	θ = 12.1–17.8°
c = 9.056 (2) Å	µ = 4.41 mm^−1
α = 112.52 (3)°	T = 223 K
β = 108.53 (3)°	Prism, colourless
γ = 97.31 (3)°	0.25 × 0.23 × 0.22 mm
V = 461.5 (3) Å^3

Data collection

Enraf–Nonius CAD-4 diffractometer	1611 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.017
Graphite monochromator	θmax = 27.9°, θmin = 3.1°
non–profiled ω–2θ scans	h = −9→9
Absorption correction: ψ scan (North et al., 1968)	k = −11→10
Tmin = 0.321, Tmax = 0.379	l = −10→11
2879 measured reflections	3 standard reflections every 120 min
2204 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.026	Hydrogen site location: difference Fourier map
wR(F^2) = 0.072	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0407P)^2 + 0.0613P] where P = (Fo^2 + 2Fc^2)/3
2204 reflections	(Δ/σ)max < 0.001
109 parameters	Δρmax = 0.32 e Å^−3
0 restraints	Δρmin = −0.29 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.75795 (5)	0.34439 (3)	0.06516 (3)	0.04738 (11)
O1	0.2799 (4)	0.3219 (3)	0.0357 (3)	0.0670 (6)
H1W	0.4075	0.3492	0.0566	0.080*
H2W	0.2270	0.3935	0.0036	0.080*
N1	0.2302 (3)	0.2360 (3)	0.2791 (3)	0.0391 (5)
H1	0.2229	0.2590	0.1887	0.047*
N2	0.2405 (3)	0.3529 (3)	0.4332 (3)	0.0386 (5)
H2	0.2427	0.4673	0.4639	0.046*
N3	0.2624 (3)	−0.1852 (3)	0.6571 (3)	0.0374 (4)
H3	0.2742	−0.2079	0.7485	0.045*
N4	0.2389 (3)	−0.3083 (2)	0.4992 (3)	0.0376 (4)
C1	0.2315 (4)	0.0800 (3)	0.2806 (3)	0.0361 (5)
H1A	0.2260	−0.0256	0.1861	0.043*
C2	0.2423 (3)	0.0954 (3)	0.4417 (3)	0.0277 (4)
C3	0.2472 (4)	0.2709 (3)	0.5333 (3)	0.0353 (5)
H3A	0.2543	0.3245	0.6502	0.042*
C4	0.2663 (4)	−0.0257 (3)	0.6617 (3)	0.0361 (5)
H4A	0.2803	0.0805	0.7598	0.043*
C5	0.2464 (3)	−0.0416 (3)	0.5001 (3)	0.0290 (4)
C6	0.2298 (4)	−0.2200 (3)	0.4041 (3)	0.0360 (5)
H6A	0.2137	−0.2727	0.2846	0.043*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br1	0.0733 (2)	0.04043 (15)	0.04186 (15)	0.02333 (13)	0.02914 (13)	0.02453 (11)
O1	0.0938 (17)	0.0729 (15)	0.0831 (16)	0.0444 (13)	0.0552 (14)	0.0604 (13)
N1	0.0564 (13)	0.0318 (10)	0.0464 (11)	0.0199 (9)	0.0279 (10)	0.0263 (9)
N2	0.0508 (12)	0.0255 (9)	0.0510 (12)	0.0178 (9)	0.0257 (10)	0.0222 (9)
N3	0.0513 (12)	0.0333 (10)	0.0379 (10)	0.0161 (9)	0.0202 (9)	0.0228 (8)
N4	0.0539 (12)	0.0233 (9)	0.0431 (11)	0.0147 (9)	0.0216 (10)	0.0192 (8)
C1	0.0502 (14)	0.0280 (10)	0.0411 (12)	0.0187 (10)	0.0250 (11)	0.0185 (10)
C2	0.0325 (11)	0.0194 (9)	0.0362 (11)	0.0109 (8)	0.0162 (9)	0.0142 (8)
C3	0.0491 (14)	0.0238 (10)	0.0412 (12)	0.0162 (9)	0.0231 (11)	0.0169 (9)
C4	0.0484 (14)	0.0271 (11)	0.0355 (12)	0.0133 (10)	0.0181 (11)	0.0149 (9)
C5	0.0354 (11)	0.0217 (10)	0.0355 (11)	0.0120 (8)	0.0161 (9)	0.0154 (9)
C6	0.0534 (14)	0.0243 (10)	0.0380 (12)	0.0155 (10)	0.0226 (11)	0.0169 (9)

Geometric parameters (Å, º)

O1—H1W	0.8500	N4—C6	1.335 (3)
O1—H2W	0.8500	C1—C2	1.389 (3)
N1—C1	1.334 (3)	C1—H1A	0.9600
N1—N2	1.340 (3)	C2—C3	1.392 (3)
N1—H1	0.8999	C2—C5	1.452 (3)
N2—C3	1.333 (3)	C3—H3A	0.9600
N2—H2	0.9000	C4—C5	1.375 (3)
N3—C4	1.338 (3)	C4—H4A	0.9600
N3—N4	1.351 (3)	C5—C6	1.397 (3)
N3—H3	0.9000	C6—H6A	0.9600
H1W—O1—H2W	108.4	C1—C2—C5	127.55 (19)
C1—N1—N2	109.23 (19)	C3—C2—C5	128.01 (19)
C1—N1—H1	125.4	N2—C3—C2	109.2 (2)
N2—N1—H1	125.4	N2—C3—H3A	125.3
C3—N2—N1	108.32 (18)	C2—C3—H3A	125.4
C3—N2—H2	125.9	N3—C4—C5	107.6 (2)
N1—N2—H2	125.8	N3—C4—H4A	126.2
C4—N3—N4	111.97 (18)	C5—C4—H4A	126.2
C4—N3—H3	124.0	C4—C5—C6	104.28 (19)
N4—N3—H3	124.0	C4—C5—C2	128.0 (2)
C6—N4—N3	104.60 (18)	C6—C5—C2	127.7 (2)
N1—C1—C2	108.8 (2)	N4—C6—C5	111.6 (2)
N1—C1—H1A	125.6	N4—C6—H6A	124.2
C2—C1—H1A	125.6	C5—C6—H6A	124.2
C1—C2—C3	104.45 (18)
C1—N1—N2—C3	−0.3 (3)	N3—C4—C5—C6	0.3 (3)
C4—N3—N4—C6	0.5 (3)	N3—C4—C5—C2	−180.0 (2)
N2—N1—C1—C2	0.2 (3)	C1—C2—C5—C4	176.8 (2)
N1—C1—C2—C3	0.0 (3)	C3—C2—C5—C4	−3.6 (4)
N1—C1—C2—C5	179.7 (2)	C1—C2—C5—C6	−3.6 (4)
N1—N2—C3—C2	0.4 (3)	C3—C2—C5—C6	176.0 (2)
C1—C2—C3—N2	−0.2 (3)	N3—N4—C6—C5	−0.3 (3)
C5—C2—C3—N2	−179.9 (2)	C4—C5—C6—N4	−0.1 (3)
N4—N3—C4—C5	−0.5 (3)	C2—C5—C6—N4	−179.7 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.90	1.80	2.680 (3)	165
N2—H2···N4^i	0.90	1.82	2.712 (3)	173
N3—H3···Br1^ii	0.90	2.43	3.312 (2)	165
O1—H1W···Br1	0.85	2.48	3.311 (2)	165
O1—H2W···Br1^iii	0.85	2.53	3.315 (2)	154
C1—H1A···Br1^iv	0.96	2.84	3.795 (3)	174
C4—H4A···O1^v	0.96	2.56	3.503 (4)	169

Symmetry codes: (i) x, y+1, z; (ii) −x+1, −y, −z+1; (iii) −x+1, −y+1, −z; (iv) −x+1, −y, −z; (v) x, y, z+1.

(II) 4-(1H-pyrazol-4-yl)pyrazolium perchlorate monohydrate

Crystal data

C6H7N4^+·ClO4^−·H2O	Z = 2
Mr = 252.62	F(000) = 260
Triclinic, P1	Dx = 1.660 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.7691 (7) Å	Cell parameters from 23 reflections
b = 7.9578 (11) Å	θ = 7.0–14.5°
c = 9.826 (2) Å	µ = 0.39 mm^−1
α = 69.941 (18)°	T = 223 K
β = 70.38 (1)°	Prism, colourless
γ = 65.393 (8)°	0.22 × 0.20 × 0.20 mm
V = 505.43 (14) Å^3

Data collection

Enraf–Nonius CAD-4 diffractometer	1830 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.019
Graphite monochromator	θmax = 27.9°, θmin = 4.1°
non–profiled ω–2θ scans	h = −9→10
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
Tmin = 0.862, Tmax = 0.926	l = −12→12
2565 measured reflections	3 standard reflections every 120 min
2397 independent reflections	intensity decay: none

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.037	Hydrogen site location: difference Fourier map
wR(F^2) = 0.113	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0593P)^2 + 0.2131P] where P = (Fo^2 + 2Fc^2)/3
2397 reflections	(Δ/σ)max < 0.001
145 parameters	Δρmax = 0.31 e Å^−3
0 restraints	Δρmin = −0.38 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cl1	0.76133 (7)	−0.19004 (7)	0.06074 (5)	0.04157 (17)
O1	0.7079 (3)	0.2998 (3)	0.0908 (2)	0.0766 (6)
H2W	0.8163	0.3155	0.0448	0.092*
H1W	0.7105	0.1989	0.0772	0.092*
O2	0.6339 (3)	−0.1156 (3)	0.1843 (2)	0.0837 (7)
O3	0.6617 (4)	−0.2516 (4)	0.0005 (3)	0.0911 (7)
O4	0.9228 (3)	−0.3443 (3)	0.1090 (2)	0.0777 (7)
O5	0.8271 (3)	−0.0493 (3)	−0.0517 (2)	0.0877 (7)
N1	0.4313 (2)	0.4759 (2)	0.29416 (19)	0.0416 (4)
H1	0.5238	0.4457	0.2132	0.050*
N2	0.4261 (2)	0.3676 (2)	0.43137 (18)	0.0344 (3)
H2	0.5136	0.2525	0.4590	0.041*
N3	−0.2705 (2)	0.9238 (2)	0.63927 (18)	0.0370 (4)
H3	−0.3585	0.9549	0.7218	0.044*
N4	−0.2875 (2)	1.0257 (2)	0.50031 (19)	0.0358 (4)
C1	0.2784 (3)	0.6363 (3)	0.2950 (2)	0.0401 (4)
H1A	0.2482	0.7383	0.2098	0.048*
C2	0.1698 (2)	0.6311 (2)	0.43908 (18)	0.0265 (3)
C3	0.2703 (2)	0.4576 (2)	0.5216 (2)	0.0315 (4)
H3A	0.2324	0.4105	0.6271	0.038*
C4	−0.1084 (3)	0.7715 (2)	0.6405 (2)	0.0343 (4)
H4A	−0.0662	0.6794	0.7266	0.041*
C5	−0.0118 (2)	0.7712 (2)	0.49424 (18)	0.0270 (3)
C6	−0.1306 (2)	0.9337 (2)	0.4119 (2)	0.0319 (4)
H6A	−0.1019	0.9735	0.3053	0.038*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0377 (3)	0.0370 (3)	0.0285 (2)	0.00035 (18)	−0.00157 (17)	−0.00460 (17)
O1	0.0591 (11)	0.0738 (13)	0.0799 (13)	−0.0150 (10)	0.0231 (10)	−0.0459 (11)
O2	0.0624 (11)	0.0949 (15)	0.0467 (10)	0.0280 (10)	−0.0077 (8)	−0.0348 (10)
O3	0.0981 (17)	0.1006 (17)	0.0937 (17)	−0.0416 (15)	−0.0250 (14)	−0.0326 (14)
O4	0.0542 (10)	0.0645 (11)	0.0510 (10)	0.0216 (9)	−0.0044 (8)	0.0011 (8)
O5	0.0844 (15)	0.0650 (12)	0.0780 (14)	−0.0304 (12)	−0.0079 (12)	0.0210 (11)
N1	0.0338 (8)	0.0344 (8)	0.0388 (8)	−0.0002 (6)	0.0047 (6)	−0.0144 (7)
N2	0.0258 (7)	0.0233 (7)	0.0447 (9)	0.0013 (5)	−0.0083 (6)	−0.0086 (6)
N3	0.0275 (7)	0.0332 (8)	0.0402 (8)	−0.0009 (6)	0.0008 (6)	−0.0169 (7)
N4	0.0256 (7)	0.0265 (7)	0.0472 (9)	0.0005 (6)	−0.0078 (6)	−0.0115 (6)
C1	0.0402 (10)	0.0285 (8)	0.0322 (9)	0.0001 (7)	−0.0018 (8)	−0.0055 (7)
C2	0.0237 (7)	0.0215 (7)	0.0287 (8)	−0.0020 (6)	−0.0056 (6)	−0.0068 (6)
C3	0.0274 (8)	0.0258 (8)	0.0325 (8)	−0.0011 (6)	−0.0067 (7)	−0.0064 (6)
C4	0.0297 (8)	0.0303 (8)	0.0331 (9)	−0.0015 (7)	−0.0041 (7)	−0.0100 (7)
C5	0.0231 (7)	0.0209 (7)	0.0319 (8)	−0.0019 (6)	−0.0049 (6)	−0.0085 (6)
C6	0.0276 (8)	0.0242 (8)	0.0357 (9)	−0.0011 (6)	−0.0075 (7)	−0.0068 (6)

Geometric parameters (Å, º)

Cl1—O5	1.4087 (19)	N3—N4	1.346 (2)
Cl1—O2	1.4154 (17)	N3—H3	0.9000
Cl1—O3	1.419 (2)	N4—C6	1.326 (2)
Cl1—O4	1.4224 (17)	C1—C2	1.380 (2)
O1—H2W	0.8500	C1—H1A	0.9600
O1—H1W	0.8500	C2—C3	1.391 (2)
N1—N2	1.326 (2)	C2—C5	1.455 (2)
N1—C1	1.334 (2)	C3—H3A	0.9600
N1—H1	0.9000	C4—C5	1.380 (2)
N2—C3	1.325 (2)	C4—H4A	0.9600
N2—H2	0.9000	C5—C6	1.403 (2)
N3—C4	1.336 (2)	C6—H6A	0.9600
O5—Cl1—O2	110.63 (15)	N1—C1—H1A	125.9
O5—Cl1—O3	107.79 (15)	C2—C1—H1A	125.5
O2—Cl1—O3	109.65 (16)	C1—C2—C3	104.40 (15)
O5—Cl1—O4	109.55 (14)	C1—C2—C5	128.63 (15)
O2—Cl1—O4	108.53 (11)	C3—C2—C5	126.95 (15)
O3—Cl1—O4	110.70 (15)	N2—C3—C2	109.13 (15)
H2W—O1—H1W	108.2	N2—C3—H3A	125.6
N2—N1—C1	109.35 (15)	C2—C3—H3A	125.3
N2—N1—H1	125.2	N3—C4—C5	107.16 (16)
C1—N1—H1	125.4	N3—C4—H4A	126.7
C3—N2—N1	108.55 (14)	C5—C4—H4A	126.2
C3—N2—H2	125.6	C4—C5—C6	104.26 (15)
N1—N2—H2	125.9	C4—C5—C2	127.51 (15)
C4—N3—N4	112.22 (15)	C6—C5—C2	128.22 (15)
C4—N3—H3	124.0	N4—C6—C5	111.27 (16)
N4—N3—H3	123.8	N4—C6—H6A	124.3
C6—N4—N3	105.09 (14)	C5—C6—H6A	124.4
N1—C1—C2	108.57 (16)
C1—N1—N2—C3	−0.2 (2)	N3—C4—C5—C6	0.3 (2)
C4—N3—N4—C6	0.0 (2)	N3—C4—C5—C2	−178.57 (16)
N2—N1—C1—C2	−0.1 (2)	C1—C2—C5—C4	−173.36 (19)
N1—C1—C2—C3	0.2 (2)	C3—C2—C5—C4	8.5 (3)
N1—C1—C2—C5	−178.22 (17)	C1—C2—C5—C6	8.1 (3)
N1—N2—C3—C2	0.3 (2)	C3—C2—C5—C6	−170.04 (18)
C1—C2—C3—N2	−0.3 (2)	N3—N4—C6—C5	0.2 (2)
C5—C2—C3—N2	178.15 (17)	C4—C5—C6—N4	−0.3 (2)
N4—N3—C4—C5	−0.2 (2)	C2—C5—C6—N4	178.56 (16)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O1	0.90	1.81	2.665 (2)	159
N2—H2···N4^i	0.90	1.85	2.742 (2)	174
N3—H3···O2^ii	0.90	2.07	2.871 (2)	148
O1—H1W···O5	0.85	2.40	3.193 (3)	155
O1—H2W···O4^iii	0.85	2.13	2.966 (3)	168
C1—H1A···O5^iv	0.96	2.38	3.297 (3)	160
C3—H3A···O2^v	0.96	2.51	3.267 (3)	136
C3—H3A···O4^v	0.96	2.44	3.386 (3)	169

Symmetry codes: (i) x+1, y−1, z; (ii) −x, −y+1, −z+1; (iii) −x+2, −y, −z; (iv) −x+1, −y+1, −z; (v) −x+1, −y, −z+1.