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The title compound, C12H12N4O2+·2NO3, crystallizes as 1-(4-pyridinio)-2′-[4-pyridinio-(E)-methyl­idene]­hydrazide cations and nitrate anions. An extensive hydrogen-bonding network, primarily N—H...O interactions, but with supporting C—H...O contacts, leads to a three-dimensional matrix structure, which is best considered as a cationic framework with bridging nitrate anions. The basic feature of the cationic framework is a zigzag chain, which runs along the [101] direction. The chains pack to generate two-dimensional sheets which lie parallel to the (101) plane and stack in the [\overline 101] direction to give the three-dimensional matrix.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536802006050/cf6160sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536802006050/cf6160Isup2.hkl
Contains datablock I

CCDC reference: 185782

Key indicators

  • Single-crystal X-ray study
  • T = 150 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.042
  • wR factor = 0.116
  • Data-to-parameter ratio = 14.7

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


Yellow Alert Alert Level C:
REFLT_03 From the CIF: _diffrn_reflns_theta_max 28.85 From the CIF: _reflns_number_total 3595 TEST2: Reflns within _diffrn_reflns_theta_max Count of symmetry unique reflns 3795 Completeness (_total/calc) 94.73% Alert C: < 95% complete
0 Alert Level A = Potentially serious problem
0 Alert Level B = Potential problem
1 Alert Level C = Please check

Comment top

As part of our analysis of the roles of N—H···O and C—H···O hydrogen-bonding interactions in bipyridinium nitrates (Felloni et al., 2002), the synthesis and structural characterization of 3,6-bis(pyridin-4-io)-1,2,4,5-tetrazine dinitrate was targeted. The product of the reaction between 3,6-bis(pyridin-4-yl)-1,2,4,5-tetrazine and aqueous nitric acid, however, was the hydrolysis product, 1-(4-pyridinio)-2'-[4-pyridinio-(E)-methylidene]hydrazide dinitrate, (I) (Fig. 1). Since the presence of the amido moiety in the section linking the two pyridinium rings radically alters the hydrogen-bonding potential of this cation compared with that of simple bipyridinium dinitrates, we thought it appropriate to consider its structure separately.

The extended structure of (I) is complex. An extensive hydrogen-bonding network, primarily N—H···O interactions, but with supporting C—H···O contacts, leads to a three-dimensional matrix structure. The long-range structure can be considered in a number of different ways. Our preferred description is that of a cationic framework with bridging nitrate anions. The cations align along the [101] direction in the form of a one-dimensional zigzag chain (Fig. 2). A relatively short C—H···O interaction (C—H 0.95, H···O 2.28, C···O 3.13 Å and C—H···O 149°) involving α-pyridinium carbons and carbonyl O atoms links the cations in a C(6) motif (Bernstein et al., 1995). Adjacent chains are arranged in a centrosymmetric fashion in the (101) plane to generate a two-dimensional sheet structure (Fig. 2). The sheets stack in the [101] direction to give the three-dimensional matrix structure (Fig. 3).

Between the cations lie the nitrate anions which act as hydrogen-bond acceptors for both N—H···O and C—H···O interactions. Both crystallographically independent nitrate anions are surrounded by three cations; one acts as an acceptor to one N—H donor [N1—H1···O1N; Fig. 4(a)] and two C—H donors [C5—H5···O1N and C14—H14···O3N; Fig. 4(a)], the other as an acceptor to two N—H donors [N9—H9···O3R and N15—H15···O3R; Fig. 4(b)], one normal C—H donor [C6—H6···O1R; Fig 4(b)] and one bifurcated C—H donor [C17—H17···O2R,O3R; Fig. 4(b)]. The structural parameters for the N—H···O contacts (Fig. 5 and Table 1) fall into narrow ranges (Table 2), the means of which are typical of intermediate strength N—H···O hydrogen bonds (Jeffrey, 1997, 1995; Speakman, 1975). They are considerably weaker than those found in the simple bipyridinium nitrates, as illustrated by their longer N···O and H···O mean interatomic distances [2.88 and 2.02 Å (Table 3) cf. 2.74 and 1.89 Å (Felloni et al., 2002)].

The structural parameters of the C—H···O contacts also fall into a narrow range. Unlike the N—H···O contacts, however, they exhibit a lack of coplanarity between cation and anion which is manifest in H···O—N—O torsion angles in the range 40.4–47.2° (Table 1). They are typical of type-3 C—H···O contacts [Fig. 6(c); Felloni et al., 2002]. Type 1 contacts [Fig. 6(a)] are the conventional C—H···O interactions involving nitrate anions, in which the cation and anion are coplanar and the H···O—N angle is typical of sp2-hybridized oxygen (~120°). Type 2 contacts [Fig. 6(b)] differ from type 1 contacts solely in the direction of approach of the N—H donor which bisects two O atoms, giving a much larger H···O—N angle (~180°).

The structural parameters of the cation-anion C—H···O contacts in the title compound, when compared to those of the inter-cation C—H···O contact, for which not only is the torsion angle smaller but also the interatomic distances H···O and N···O are shorter (Table 1), suggest that the inter-cation C—H···O contact is the stronger interaction. As this observation conflicts with conventional arguments regarding electrostatics, it is clear that the C—H···O interactions must be considerably inferior to the N—H···O contacts.

Experimental top

A solution of 3,6-bis(pyridin-4-yl)-1,2,4,5-tetrazine (0.118 g, 0.5 mmol) in methanol (15 ml) was mixed with aqueous nitric acid (2 mol dm-3; 0.5 ml, 1 mmol). Yellow rectangular blocks of the title compound were formed in one month. Analysis found (calculated): C 41.05 (40.90), H 3.45 (3.40), N 23.40 (23.85)%. IR cm-1 (all bands due to cation unless stated otherwise): 1697 (m), 1637 (s), 1612 (s), 1570 (m), 1500 (s), 1384 (w, NO3-), 819 (s), 744 (s).

Refinement top

H atoms bonded to N atoms were refined with geometrical restraints, while those bonded to C atoms were constrained with a riding model.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2001).

Figures top
[Figure 1] Fig. 1. A view of the title compound showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probablility level.
[Figure 2] Fig. 2. A projection of the structure of the title compound on to the (101) plane, showing the C16—H16···O11 hydrogen bonds linking the cations into one-dimensional zigzag chains and the way the chains are aligned to generate the two-dimensional sheets. Anions are omitted for clarity. Atoms are identified as follows: C, black circles; N, blue circles; O, red circles; H, small yellow circles.
[Figure 3] Fig. 3. A projection of the structure of the title compound on to the (101) plane, showing the way the two-dimensional sheets are aligned to generate the three-dimensional matrix structure. Anions have been omitted for clarity. Atoms are identified as for Fig. 2.
[Figure 4] Fig. 4. (a) and (b) Projections of the structure of the title compound on to the planes of the two crystallographically independent nitrate anions, showing the N—H···O and C—H···O contacts. Atoms are identified as for Fig. 2. [Symmetry codes: (i) -1/2 + x, 3/2 - y, -1/2 + z; (ii) -1 + x, 1 + y, z; (iii) 1 + x, -1 + y, z; (iv) 3/2 - x, -1/2 + y, 3/2 - z.]
[Figure 5] Fig. 5. N—H···O hydrogen-bond contacts found in bipyridinium nitrates; τ = H···O—N—O torsion angle.
[Figure 6] Fig. 6. (a), (b) and (c) Types of C—H···O hydrogen-bond contacts found in bipyridinium nitrates; τ = H···O—N—O torsion angle.
(I) top
Crystal data top
C12H12N4O2+·2NO3Dx = 1.614 Mg m3
Mr = 352.28Melting point: unknown K
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 7.9639 (9) ÅCell parameters from 3001 reflections
b = 14.017 (2) Åθ = 2.9–27.6°
c = 13.0563 (15) ŵ = 0.14 mm1
β = 95.995 (2)°T = 150 K
V = 1449.5 (3) Å3Rectangular block, yellow
Z = 40.26 × 0.13 × 0.08 mm
F(000) = 728
Data collection top
Bruker SMART1000 CCD area-detector
diffractometer
2275 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.040
Graphite monochromatorθmax = 28.9°, θmin = 2.1°
ω scansh = 1010
10487 measured reflectionsk = 1718
3595 independent reflectionsl = 1216
Refinement top
Refinement on F2Primary atom site location: direct method
Least-squares matrix: fullSecondary atom site location: difference Fourer method
R[F2 > 2σ(F2)] = 0.042Hydrogen site location: difference Fourier map
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0615P)2]
where P = (Fo2 + 2Fc2)/3
3449 reflections(Δ/σ)max < 0.001
235 parametersΔρmax = 0.32 e Å3
3 restraintsΔρmin = 0.20 e Å3
Crystal data top
C12H12N4O2+·2NO3V = 1449.5 (3) Å3
Mr = 352.28Z = 4
Monoclinic, P21/nMo Kα radiation
a = 7.9639 (9) ŵ = 0.14 mm1
b = 14.017 (2) ÅT = 150 K
c = 13.0563 (15) Å0.26 × 0.13 × 0.08 mm
β = 95.995 (2)°
Data collection top
Bruker SMART1000 CCD area-detector
diffractometer
2275 reflections with I > 2σ(I)
10487 measured reflectionsRint = 0.040
3595 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0423 restraints
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.32 e Å3
3449 reflectionsΔρmin = 0.20 e Å3
235 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.

Pyridinium H atoms were located from /DF syntheses and refined with the N—H distance restrained to be 0.88 (1) A and with Uiso(H) = 1.5Ueq(N). Aromatic H atoms, after location from /DF syntheses were placed geometrically and refined with a riding model for which the C—H distance was constrained to be 0.96 A and Uiso(H) = 1.2Ueq(C).

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O3R0.96466 (17)0.07286 (9)0.76440 (10)0.0307 (3)
O1R1.02768 (17)0.07953 (10)0.60743 (10)0.0354 (4)
O2R1.14799 (17)0.17627 (10)0.72197 (11)0.0394 (4)
N1R1.04898 (19)0.10988 (11)0.69672 (13)0.0277 (4)
O1N0.14682 (17)0.86438 (10)0.26074 (11)0.0388 (4)
N1N0.24467 (19)0.89916 (11)0.32060 (13)0.0282 (4)
O3N0.23428 (17)0.86905 (10)0.41123 (11)0.0355 (3)
O2N0.34792 (18)0.96135 (10)0.29023 (12)0.0439 (4)
N10.02143 (19)0.70651 (11)0.38730 (14)0.0333 (4)
H10.079 (2)0.7550 (11)0.3583 (15)0.040*
C60.0371 (2)0.71637 (13)0.48571 (16)0.0322 (5)
H60.01030.77180.52270.039*
C50.1372 (2)0.64558 (13)0.53424 (15)0.0282 (4)
H50.18080.65210.60440.034*
C40.1732 (2)0.56442 (12)0.47855 (14)0.0222 (4)
C30.1057 (2)0.55751 (13)0.37634 (14)0.0269 (4)
H30.12670.50240.33730.032*
C20.0095 (2)0.62969 (14)0.33207 (16)0.0335 (5)
H20.03550.62530.26190.040*
C70.2803 (2)0.48987 (12)0.53032 (15)0.0253 (4)
H70.32540.49710.60020.030*
N80.31189 (18)0.41513 (10)0.47982 (12)0.0247 (3)
N90.41337 (18)0.34818 (11)0.53276 (12)0.0245 (3)
H90.451 (2)0.3590 (14)0.5970 (8)0.029*
C100.4481 (2)0.26557 (13)0.48578 (15)0.0274 (4)
O110.39318 (19)0.24550 (10)0.39825 (11)0.0424 (4)
C120.5661 (2)0.19818 (13)0.54911 (14)0.0251 (4)
C130.6137 (2)0.11657 (13)0.49977 (15)0.0297 (4)
H130.57220.10500.43000.036*
C140.7217 (2)0.05217 (13)0.55246 (15)0.0313 (5)
H140.75500.00400.51920.038*
N150.77876 (19)0.06924 (11)0.65007 (13)0.0281 (4)
H150.844 (2)0.0264 (11)0.6845 (14)0.034*
C160.7354 (2)0.14668 (13)0.70104 (15)0.0298 (4)
H160.77780.15590.77110.036*
C170.6291 (2)0.21258 (13)0.65112 (15)0.0294 (4)
H170.59850.26820.68640.035*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O3R0.0361 (7)0.0301 (7)0.0256 (7)0.0046 (6)0.0026 (6)0.0009 (6)
O1R0.0419 (8)0.0371 (8)0.0266 (8)0.0087 (6)0.0004 (6)0.0032 (6)
O2R0.0326 (7)0.0334 (8)0.0512 (10)0.0106 (6)0.0009 (7)0.0088 (7)
N1R0.0257 (8)0.0230 (8)0.0334 (10)0.0015 (6)0.0017 (7)0.0002 (7)
O1N0.0387 (8)0.0422 (8)0.0346 (8)0.0072 (7)0.0001 (7)0.0048 (7)
N1N0.0268 (8)0.0209 (8)0.0348 (10)0.0008 (6)0.0067 (7)0.0009 (7)
O3N0.0373 (7)0.0342 (8)0.0345 (9)0.0054 (6)0.0012 (6)0.0061 (6)
O2N0.0415 (8)0.0318 (8)0.0551 (10)0.0136 (6)0.0110 (7)0.0060 (7)
N10.0264 (8)0.0214 (8)0.0491 (11)0.0042 (7)0.0097 (8)0.0046 (8)
C60.0276 (9)0.0218 (10)0.0472 (13)0.0007 (8)0.0041 (9)0.0074 (9)
C50.0277 (9)0.0301 (10)0.0262 (10)0.0031 (8)0.0003 (8)0.0027 (8)
C40.0189 (8)0.0199 (8)0.0279 (10)0.0006 (7)0.0027 (7)0.0035 (7)
C30.0284 (9)0.0245 (9)0.0272 (10)0.0014 (7)0.0004 (8)0.0033 (8)
C20.0354 (10)0.0318 (11)0.0310 (12)0.0005 (8)0.0077 (9)0.0009 (8)
C70.0243 (9)0.0240 (9)0.0268 (10)0.0005 (7)0.0002 (8)0.0031 (8)
N80.0225 (7)0.0217 (8)0.0299 (9)0.0027 (6)0.0020 (6)0.0052 (7)
N90.0250 (7)0.0234 (8)0.0240 (9)0.0055 (6)0.0031 (6)0.0028 (7)
C100.0303 (10)0.0263 (10)0.0253 (11)0.0020 (8)0.0005 (8)0.0029 (8)
O110.0597 (10)0.0366 (8)0.0282 (8)0.0143 (7)0.0082 (7)0.0001 (6)
C120.0244 (9)0.0228 (9)0.0279 (10)0.0015 (7)0.0024 (8)0.0062 (8)
C130.0347 (10)0.0310 (10)0.0229 (10)0.0011 (8)0.0010 (8)0.0002 (8)
C140.0359 (10)0.0256 (10)0.0331 (12)0.0054 (8)0.0076 (9)0.0041 (8)
N150.0255 (8)0.0241 (8)0.0335 (9)0.0056 (6)0.0019 (7)0.0037 (7)
C160.0318 (9)0.0296 (10)0.0267 (11)0.0013 (8)0.0025 (8)0.0027 (8)
C170.0305 (9)0.0229 (9)0.0342 (11)0.0037 (8)0.0004 (8)0.0042 (8)
Geometric parameters (Å, º) top
O3R—N1R1.275 (2)C7—N81.277 (2)
O1R—N1R1.236 (2)C7—H70.9500
O2R—N1R1.2418 (19)N8—N91.376 (2)
O1N—N1N1.258 (2)N9—C101.353 (2)
N1N—O2N1.2349 (19)N9—H90.874 (9)
N1N—O3N1.251 (2)C10—O111.213 (2)
N1—C61.327 (3)C10—C121.515 (2)
N1—C21.333 (3)C12—C131.385 (3)
N1—H10.882 (9)C12—C171.388 (3)
C6—C51.384 (3)C13—C141.380 (3)
C6—H60.9500C13—H130.9500
C5—C41.396 (3)C14—N151.329 (2)
C5—H50.9500C14—H140.9500
C4—C31.389 (2)N15—C161.337 (2)
C4—C71.469 (2)N15—H150.887 (9)
C3—C21.361 (3)C16—C171.371 (3)
C3—H30.9500C16—H160.9500
C2—H20.9500C17—H170.9500
O1R—N1R—O2R121.94 (17)C4—C7—H7120.6
O1R—N1R—O3R118.91 (14)C7—N8—N9115.92 (15)
O2R—N1R—O3R119.14 (16)C10—N9—N8119.55 (15)
O2N—N1N—O3N121.19 (17)C10—N9—H9121.2 (13)
O2N—N1N—O1N120.59 (17)N8—N9—H9119.2 (13)
O3N—N1N—O1N118.22 (15)O11—C10—N9123.70 (17)
C6—N1—C2122.80 (16)O11—C10—C12120.76 (17)
C6—N1—H1116.7 (14)N9—C10—C12115.52 (16)
C2—N1—H1120.5 (14)C13—C12—C17118.52 (16)
N1—C6—C5119.70 (18)C13—C12—C10116.44 (16)
N1—C6—H6120.2C17—C12—C10125.04 (17)
C5—C6—H6120.2C14—C13—C12119.67 (18)
C6—C5—C4119.05 (18)C14—C13—H13120.2
C6—C5—H5120.5C12—C13—H13120.2
C4—C5—H5120.5N15—C14—C13119.55 (17)
C3—C4—C5118.52 (16)N15—C14—H14120.2
C3—C4—C7122.71 (17)C13—C14—H14120.2
C5—C4—C7118.77 (17)C14—N15—C16122.88 (16)
C2—C3—C4120.02 (18)C14—N15—H15119.2 (13)
C2—C3—H3120.0C16—N15—H15117.8 (13)
C4—C3—H3120.0N15—C16—C17119.28 (18)
N1—C2—C3119.89 (18)N15—C16—H16120.4
N1—C2—H2120.1C17—C16—H16120.4
C3—C2—H2120.1C16—C17—C12120.10 (17)
N8—C7—C4118.85 (17)C16—C17—H17120.0
N8—C7—H7120.6C12—C17—H17120.0
C2—N1—C6—C51.2 (3)N8—N9—C10—C12177.82 (15)
N1—C6—C5—C40.7 (3)O11—C10—C12—C133.5 (3)
C6—C5—C4—C30.5 (3)N9—C10—C12—C13175.19 (17)
C6—C5—C4—C7179.62 (17)O11—C10—C12—C17176.79 (19)
C5—C4—C3—C21.2 (3)N9—C10—C12—C174.5 (3)
C7—C4—C3—C2178.89 (17)C17—C12—C13—C140.1 (3)
C6—N1—C2—C30.4 (3)C10—C12—C13—C14179.64 (18)
C4—C3—C2—N10.8 (3)C12—C13—C14—N150.0 (3)
C3—C4—C7—N80.6 (3)C13—C14—N15—C160.5 (3)
C5—C4—C7—N8179.26 (17)C14—N15—C16—C170.8 (3)
C4—C7—N8—N9179.86 (15)N15—C16—C17—C120.7 (3)
C7—N8—N9—C10177.81 (17)C13—C12—C17—C160.2 (3)
N8—N9—C10—O110.8 (3)C10—C12—C17—C16179.97 (18)

Experimental details

Crystal data
Chemical formulaC12H12N4O2+·2NO3
Mr352.28
Crystal system, space groupMonoclinic, P21/n
Temperature (K)150
a, b, c (Å)7.9639 (9), 14.017 (2), 13.0563 (15)
β (°) 95.995 (2)
V3)1449.5 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.14
Crystal size (mm)0.26 × 0.13 × 0.08
Data collection
DiffractometerBruker SMART1000 CCD area-detector
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
10487, 3595, 2275
Rint0.040
(sin θ/λ)max1)0.679
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.042, 0.116, 1.00
No. of reflections3449
No. of parameters235
No. of restraints3
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.32, 0.20

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 2000), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), CAMERON (Watkin et al., 1996), SHELXL97 and PLATON (Spek, 2001).

Hydrogen bonding parameters. ators is the average of the two H···O-N-O torsion angles. Symmetry codes:(iii) x+1, y-1, z;(v) 3/2-x, 1/2+y, 3/2-z; (vi) 1/2+x, 1/2-y, 1/2+z; (vii) 1/2+x, 3/2-y, 1/2+z; (viii) x-1, y+1, z. top
ContactX-HH···OX···OX-H···OH···O-Ntorsa
N1-H1···O1N0.882.032.878 (3)1619313.4
N9-H9···O3Rv0.872.092.940 (3)1631063.2
N15-H15···O3R0.891.932.815 (3)1741012.8
C16-H16···O11vi0.952.283.133 (3)14912917.9
C5-H5···O1Nvii0.952.353.265 (3)16210440.4
C6-H6···O1Rviii0.952.363.277 (3)1639844.6
C14-H14···O3Niii0.952.283.201 (3)16410943.9
C17-H17···O2Rv0.952.533.287 (3)1378244.4
C17-H17···O3Rv0.952.393.315 (3)1668747.2
Interatomic distances and angles (ranges and means; (%A, °) for the N-H···O hydrogen-bonding interactions. top
ContactMinimumMaximumMean
N···O2.815 (3)2.940 (3)2.878 (3)
H···O1.932.092.02 (8)
N-H···O161174166 (7)
H···O-N93106100 (6)
H···O-N-O2.813.47(4)
 

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