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Acta Crystallogr Sect E Struct Rep Online. 2010 February 1; 66(Pt 2): o358.
Published online 2010 January 16. doi:  10.1107/S1600536810000942
PMCID: PMC2979822

Bis(2-amino-3-nitro­pyridinium) dihydrogen­diphosphate

Abstract

The structure of the title compound, 2C5H6N3O2 +·H2P2O7 2−, contains infinite (H2P2O7 2−)n layers stacked perpendicular to the a axis. The 2-amino-3-nitro­pyridinium cations are arranged in pairs and are anchored between these layers, linking them by N—H(...)O and C—H(...)O hydrogen-bonding and electrostatic inter­actions between anionic and cationic species to form a three-dimensional network.

Related literature

For related structures of 2-amino-3-nitro­pyridinium, see: Akriche & Rzaigui (2000 [triangle], 2009a [triangle],b [triangle],c [triangle]); Nicoud et al. (1997 [triangle]). For bond lengths in related structures, see: Aakeröy et al. (1998 [triangle]). For related structures of diphosphate anions, see: Akriche & Rzaigui (2005 [triangle]); Charfi & Jouini (2005 [triangle]); Brodski et al. (2004 [triangle]); Mrad et al. (2006 [triangle]); Soumhi et al. (1998 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o358-scheme1.jpg

Experimental

Crystal data

  • 2C5H6N3O2 +·H2O7P2 2−
  • M r = 456.21
  • Orthorhombic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o358-efi1.jpg
  • a = 34.250 (5) Å
  • b = 5.763 (2) Å
  • c = 8.991 (3) Å
  • V = 1774.8 (9) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.32 mm−1
  • T = 298 K
  • 0.29 × 0.25 × 0.19 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • 2726 measured reflections
  • 2724 independent reflections
  • 2279 reflections with I > 2σ(I)
  • R int = 0.008
  • 2 standard reflections every 120 min intensity decay: 3%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.033
  • wR(F 2) = 0.091
  • S = 1.09
  • 2724 reflections
  • 265 parameters
  • 1 restraint
  • H-atom parameters constrained
  • Δρmax = 0.53 e Å−3
  • Δρmin = −0.28 e Å−3
  • Absolute structure: Flack (1983 [triangle]), 443 Friedel pairs
  • Flack parameter: −0.15 (11)

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 [triangle]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and DIAMOND (Brandenburg & Putz, 2005 [triangle]); software used to prepare material for publication: WinGX (Farrugia, 1999 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810000942/dn2529sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810000942/dn2529Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

In the framework of our systematic research using the 2-amino-3-nitropyridine (2 A3NP) molecule, we report here the new non-centrosymetric compound, 2(C5H6N3O2)+, H2P2O72- (I) obtained by the interaction of the 2 A3NP molecule and diphosphoric acid.

The asymmetric unit of the title compound is built up from one anion H2P2O72- and two (C5H6N3O2)+ cations as shown in Fig. 1.

The dihydrogendiphosphate anions are connected through strong hydrogen bonds characterized by relatively short distances (with distances O2···O5 = 2.549 (3) Å and O7···O1 = 2.537 (3) Å (Table 1)), to form corrugated layers parallel to bc plane at x = 0 and x= 1/2 (Fig. 2). Two crystallographically independent cations coexist in this structure. They are arranged in pairs and anchored onto both adjacent anionic layers via N—H···O and C—H···O hydrogen bonds to keep up the three-dimensionel network cohesion.

As expected, the H2P2O72- group with bent configuration shows its standard geometry, the longest bonds length P2–O4 = 1.592 (2) Å and P1–O4 = 1.613 (2) Å, correspond to the bridging oxygen atom, the intermediate ones, P1–O2 = 1.552 (2) Å and P2–O7 = 1.545 (2) Å, correspond to the P–OH bonding and the shortest ones spreading between 1.481 (2) Å and 1.515 (2) Å, correspond to the external oxygen atoms. The average values of the P–O distances and O–P–O angles are 1.536 Å and 109.3°. The P–P distance is 2.898 (1) Å and the P–O–P angle is close to 129.4 (1) °. All these distances and angles are similar to those commonly observed in others diphosphate anions (Akriche & Rzaigui, 2005; Charfi & Jouini, 2005; Brodski, et al., 2004; Mrad, et al., 2006). Despite the limited number of organic cation diphosphates (about twenty seven related structures of diphosphate anions), we can distinguish only one non-centrosymmetric structure (Soumhi, et al., 1998) such as the title compound (I).

In this atomic arrangement, one can distinguish the inter-cation contact C8—H8···O9 (H8···O9 = 2.52 Å) which induces the aggregation of the two independent organic cations in pairs (2 A3NP+)2. This kind of arrangement is also observed in the related structure of 2-amino-3-nitropyridinium hydrogenselenate (Akriche & Rzaigui, 2009b). These pairs are located between the anionic layers to link them by manifesting different interactions (Fig. 2). The geometric features of organic cations are usual and comparable with values of other 2-amino-3-nitropyridinium compounds (Akriche & Rzaigui, 2000; Nicoud et al.,1997; Akriche & Rzaigui, 2009a, 2009b, 2009c). It is worth noticing, the C—NH2 (1.316 (4) Å) and C—NO2 (1.440 (4) and 1.454 (5) Å) distances in the 2 A3NP cations are respectively shortened and lengthened with respect to the C—NH2 (1.337 (4) Å) and C—NO2 (1.429 (4) Å) observed in the 2-amino-3-nitropyridine molecular crystal (Aakeröy, et al., 1998). All the 2-amino-3-nitropyridinium cations encapsulated in various anionic subnetworks show the same changes in C—NH2 and C—NO2 distances, revealing a weak increase of pi bond character in C—NH2 and a decrease in C—NO2.

Experimental

Single crystals of the title compound were prepared at room temperature by slow evaporation of a mixture of an aqueous solution (20 ml) of diphosphoric acid (5 mmol) and an ethanolic solution (10 ml) of 2-amino-3-nitropyridine (4 mmol, 354 mg). The diphosphoric acid was produced from Na4P2O7 by using a cation-exchange resin (Amberlite IR 120). The resulting solution was evaporated slowly at room temperature for several days until the formation of good quality of prismatic single crystals.

Refinement

All H atoms attached to C, N and O atoms were fixed geometrically and treated as riding, with C—H = 0.93 Å, N—H = 0.86 Å and O—H = 0.82 Å and with Uiso(H) = 1.2Ueq(C or N) and Uiso(H) = 1.5Ueq(O)

Figures

Fig. 1.
An ORTEP view of (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii. Hydrogen bonds are represented as dashed lines.
Fig. 2.
Projection of (I) along the b axis. The H-atoms not involved in H-bonding are omitted.

Crystal data

2C5H6N3O2+·H2O7P22F(000) = 936
Mr = 456.21Dx = 1.707 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 25 reflections
a = 34.250 (5) Åθ = 10–12°
b = 5.763 (2) ŵ = 0.32 mm1
c = 8.991 (3) ÅT = 298 K
V = 1774.8 (9) Å3Prism, yellow
Z = 40.29 × 0.25 × 0.19 mm

Data collection

Enraf–Nonius CAD-4 diffractometerRint = 0.008
Radiation source: fine-focus sealed tubeθmax = 30.0°, θmin = 3.3°
graphiteh = −48→0
non–profiled ω scansk = 0→8
2726 measured reflectionsl = −12→0
2724 independent reflections2 standard reflections every 120 min
2279 reflections with I > 2σ(I) intensity decay: 3%

Refinement

Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.033w = 1/[σ2(Fo2) + (0.0391P)2 + 0.7964P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.091(Δ/σ)max = 0.001
S = 1.09Δρmax = 0.53 e Å3
2724 reflectionsΔρmin = −0.28 e Å3
265 parametersExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
1 restraintExtinction coefficient: 0.0192 (12)
Primary atom site location: structure-invariant direct methodsAbsolute structure: Flack (1983)
Secondary atom site location: difference Fourier mapFlack parameter: −0.15 (11)

Special details

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)

xyzUiso*/Ueq
P10.05181 (2)0.76331 (12)0.64677 (9)0.02939 (15)
P20.06740 (2)0.49228 (13)0.38188 (9)0.02940 (15)
O10.02869 (6)0.6068 (4)0.7473 (3)0.0388 (5)
O20.03160 (6)1.0043 (4)0.6468 (3)0.0380 (5)
H20.04321.09160.58980.057*
O30.09419 (6)0.7686 (4)0.6795 (3)0.0406 (5)
O40.04503 (6)0.6839 (4)0.4767 (2)0.0349 (4)
O50.06725 (7)0.2687 (4)0.4645 (3)0.0442 (6)
O60.10798 (6)0.5779 (4)0.3433 (3)0.0381 (5)
O70.04355 (6)0.4892 (4)0.2361 (2)0.0367 (5)
H70.02070.45920.25480.055*
O80.17007 (11)0.0987 (8)1.2413 (5)0.0996 (14)
O90.17848 (8)0.4036 (7)1.1115 (4)0.0796 (12)
O100.17870 (9)−0.0306 (6)0.8224 (4)0.0689 (9)
O110.23687 (9)0.0861 (7)0.8703 (5)0.0899 (12)
N10.07030 (7)0.3161 (5)0.9226 (3)0.0334 (5)
H10.06060.40780.85670.040*
N20.12502 (8)0.5449 (5)0.9194 (3)0.0445 (7)
H2A0.11390.62990.85320.053*
H2B0.14810.57880.94990.053*
N30.15874 (9)0.2373 (7)1.1479 (5)0.0578 (9)
N40.16725 (8)0.4967 (5)0.5130 (4)0.0396 (6)
H40.14650.51910.46080.048*
N50.13779 (8)0.1725 (6)0.6059 (4)0.0522 (8)
H5A0.11840.19980.54790.063*
H5B0.13740.05360.66370.063*
N60.20652 (10)0.1031 (6)0.8028 (4)0.0548 (8)
C10.04851 (9)0.1383 (5)0.9672 (4)0.0374 (6)
H1A0.02360.11960.92810.045*
C20.06201 (11)−0.0169 (6)1.0689 (4)0.0450 (8)
H2C0.0469−0.14311.09780.054*
C30.09860 (10)0.0180 (6)1.1278 (4)0.0453 (8)
H30.1084−0.08431.19860.054*
C40.12081 (9)0.2041 (6)1.0822 (4)0.0404 (7)
C50.10672 (8)0.3631 (5)0.9740 (4)0.0350 (6)
C60.19675 (10)0.6453 (6)0.4979 (5)0.0470 (8)
H60.19430.76780.43120.056*
C70.23056 (10)0.6223 (7)0.5778 (5)0.0550 (10)
H7C0.25120.72550.56520.066*
C80.23302 (9)0.4406 (7)0.6779 (4)0.0511 (9)
H80.25540.42210.73520.061*
C90.20255 (9)0.2872 (6)0.6933 (4)0.0417 (7)
C100.16813 (9)0.3125 (6)0.6061 (4)0.0389 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
P10.0326 (3)0.0309 (3)0.0247 (3)−0.0046 (3)−0.0008 (3)0.0044 (3)
P20.0323 (3)0.0269 (3)0.0291 (3)−0.0007 (3)0.0004 (3)0.0045 (3)
O10.0377 (10)0.0429 (12)0.0357 (11)−0.0058 (9)−0.0001 (9)0.0130 (10)
O20.0473 (11)0.0334 (10)0.0333 (11)−0.0004 (9)0.0047 (10)0.0004 (11)
O30.0373 (10)0.0474 (12)0.0371 (13)−0.0090 (10)−0.0036 (9)0.0097 (10)
O40.0379 (10)0.0374 (10)0.0293 (10)0.0054 (9)−0.0045 (9)0.0000 (9)
O50.0461 (13)0.0321 (11)0.0544 (15)−0.0020 (9)0.0013 (11)0.0162 (11)
O60.0336 (10)0.0412 (11)0.0394 (12)−0.0049 (9)0.0003 (9)0.0102 (10)
O70.0357 (10)0.0457 (12)0.0288 (10)−0.0050 (10)−0.0004 (9)−0.0028 (10)
O80.072 (2)0.126 (3)0.101 (3)0.007 (2)−0.035 (2)0.058 (3)
O90.0414 (14)0.108 (3)0.089 (3)−0.0142 (16)−0.0172 (16)0.035 (2)
O100.0647 (18)0.073 (2)0.069 (2)−0.0055 (16)−0.0033 (15)0.0349 (18)
O110.0635 (19)0.114 (3)0.092 (3)0.0031 (19)−0.025 (2)0.045 (3)
N10.0393 (13)0.0353 (13)0.0257 (11)0.0034 (10)−0.0001 (9)0.0036 (10)
N20.0426 (14)0.0462 (16)0.0447 (17)−0.0056 (12)−0.0057 (12)0.0137 (13)
N30.0423 (15)0.079 (2)0.0518 (17)0.0116 (17)−0.0067 (16)0.018 (2)
N40.0325 (11)0.0423 (14)0.0440 (15)0.0013 (11)−0.0029 (11)0.0083 (13)
N50.0423 (15)0.0524 (17)0.062 (2)−0.0119 (13)−0.0101 (15)0.0222 (16)
N60.0492 (16)0.066 (2)0.0494 (18)0.0083 (16)0.0005 (15)0.0154 (17)
C10.0393 (15)0.0418 (16)0.0309 (14)−0.0026 (13)0.0037 (13)−0.0027 (14)
C20.0549 (19)0.0353 (16)0.0447 (18)−0.0021 (15)0.0087 (16)0.0062 (15)
C30.0535 (17)0.0414 (16)0.0411 (19)0.0132 (14)0.0058 (15)0.0119 (16)
C40.0373 (15)0.0488 (18)0.0350 (16)0.0079 (13)−0.0004 (13)0.0054 (15)
C50.0372 (14)0.0390 (16)0.0288 (13)0.0054 (12)0.0018 (12)0.0035 (13)
C60.0419 (17)0.0463 (18)0.053 (2)−0.0023 (14)0.0041 (15)0.0086 (17)
C70.0374 (17)0.061 (2)0.066 (3)−0.0102 (16)0.0042 (18)0.008 (2)
C80.0303 (14)0.072 (2)0.051 (2)0.0006 (16)−0.0028 (15)0.0070 (19)
C90.0329 (13)0.0520 (18)0.0404 (15)0.0050 (13)0.0030 (12)0.0089 (16)
C100.0345 (14)0.0408 (16)0.0412 (16)0.0024 (13)0.0042 (13)0.0041 (13)

Geometric parameters (Å, °)

P1—O31.481 (2)N4—C61.331 (4)
P1—O11.503 (2)N4—C101.353 (4)
P1—O21.552 (2)N4—H40.8600
P1—O41.613 (2)N5—C101.316 (4)
P2—O51.487 (2)N5—H5A0.8600
P2—O61.515 (2)N5—H5B0.8600
P2—O71.545 (2)N6—C91.454 (5)
P2—O41.592 (2)C1—C21.360 (5)
O2—H20.8200C1—H1A0.9300
O7—H70.8200C2—C31.375 (5)
O8—N31.222 (5)C2—H2C0.9300
O9—N31.217 (5)C3—C41.377 (5)
O10—N61.238 (4)C3—H30.9300
O11—N61.208 (4)C4—C51.420 (4)
N1—C11.330 (4)C6—C71.369 (5)
N1—C51.358 (4)C6—H60.9300
N1—H10.8600C7—C81.383 (5)
N2—C51.316 (4)C7—H7C0.9300
N2—H2A0.8600C8—C91.375 (5)
N2—H2B0.8600C8—H80.9300
N3—C41.440 (4)C9—C101.423 (5)
O3—P1—O1114.15 (13)O10—N6—C9118.6 (3)
O3—P1—O2114.74 (13)N1—C1—C2121.2 (3)
O1—P1—O2107.60 (13)N1—C1—H1A119.4
O3—P1—O4109.59 (13)C2—C1—H1A119.4
O1—P1—O4108.93 (14)C1—C2—C3118.2 (3)
O2—P1—O4100.93 (13)C1—C2—H2C120.9
O5—P2—O6113.55 (13)C3—C2—H2C120.9
O5—P2—O7114.34 (15)C2—C3—C4120.2 (3)
O6—P2—O7107.14 (13)C2—C3—H3119.9
O5—P2—O4109.41 (14)C4—C3—H3119.9
O6—P2—O4109.76 (13)C3—C4—C5121.2 (3)
O7—P2—O4101.99 (12)C3—C4—N3118.7 (3)
P1—O2—H2109.5C5—C4—N3120.1 (3)
P2—O4—P1129.43 (14)N2—C5—N1118.0 (3)
P2—O7—H7109.5N2—C5—C4127.4 (3)
C1—N1—C5124.5 (3)N1—C5—C4114.6 (3)
C1—N1—H1117.7N4—C6—C7121.7 (4)
C5—N1—H1117.7N4—C6—H6119.1
C5—N2—H2A120.0C7—C6—H6119.1
C5—N2—H2B120.0C6—C7—C8117.8 (3)
H2A—N2—H2B120.0C6—C7—H7C121.1
O9—N3—O8121.5 (4)C8—C7—H7C121.1
O9—N3—C4119.7 (3)C9—C8—C7120.4 (3)
O8—N3—C4118.8 (4)C9—C8—H8119.8
C6—N4—C10123.4 (3)C7—C8—H8119.8
C6—N4—H4118.3C8—C9—C10120.5 (3)
C10—N4—H4118.3C8—C9—N6117.8 (3)
C10—N5—H5A120.0C10—C9—N6121.7 (3)
C10—N5—H5B120.0N5—C10—N4117.6 (3)
H5A—N5—H5B120.0N5—C10—C9126.3 (3)
O11—N6—O10122.7 (4)N4—C10—C9116.1 (3)
O11—N6—C9118.7 (3)
O5—P2—O4—P153.0 (2)N3—C4—C5—N21.9 (6)
O6—P2—O4—P1−72.2 (2)C3—C4—C5—N10.4 (5)
O7—P2—O4—P1174.45 (18)N3—C4—C5—N1−178.7 (3)
O3—P1—O4—P239.2 (2)C10—N4—C6—C7−0.5 (6)
O1—P1—O4—P2−86.3 (2)N4—C6—C7—C8−1.1 (6)
O2—P1—O4—P2160.61 (18)C6—C7—C8—C91.2 (6)
C5—N1—C1—C2−1.3 (5)C7—C8—C9—C100.2 (6)
N1—C1—C2—C31.6 (5)C7—C8—C9—N6−178.6 (4)
C1—C2—C3—C4−0.9 (5)O11—N6—C9—C8−3.4 (6)
C2—C3—C4—C5−0.1 (5)O10—N6—C9—C8177.0 (4)
C2—C3—C4—N3179.0 (4)O11—N6—C9—C10177.8 (4)
O9—N3—C4—C3−178.4 (4)O10—N6—C9—C10−1.8 (5)
O8—N3—C4—C30.5 (6)C6—N4—C10—N5−176.9 (4)
O9—N3—C4—C50.7 (6)C6—N4—C10—C91.9 (5)
O8—N3—C4—C5179.6 (4)C8—C9—C10—N5177.0 (4)
C1—N1—C5—N2179.7 (3)N6—C9—C10—N5−4.2 (6)
C1—N1—C5—C40.2 (4)C8—C9—C10—N4−1.7 (5)
C3—C4—C5—N2−179.0 (3)N6—C9—C10—N4177.1 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O2—H2···O5i0.821.732.549 (3)178
O7—H7···O1ii0.821.732.537 (3)166
N1—H1···O10.861.872.706 (3)165
N2—H2A···O30.861.882.726 (4)168
N2—H2B···O90.862.052.645 (4)126
N4—H4···O60.861.722.582 (4)174
N5—H5A···O50.861.952.786 (4)165
N5—H5B···O100.862.072.669 (5)126
N5—H5B···O3iii0.862.222.843 (4)130
C2—H2C···O7iv0.932.463.280 (4)147
C3—H3···O6iv0.932.343.208 (4)155
C8—H8···O9v0.932.523.097 (4)120

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: DN2529).

References

  • Aakeröy, C. B., Beatty, A. M., Nieuwenhuyzen, M. & Zou, M. (1998). J. Mater. Chem. pp. 1385–1389.
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