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Acta Crystallogr Sect E Struct Rep Online. 2010 February 1; 66(Pt 2): o479–o480.
Published online 2010 January 30. doi:  10.1107/S1600536810001443
PMCID: PMC2979855

2,3-Diamino­pyridinium benzoate benzoic acid solvate

Abstract

In the title compound, C5H8N3 +·C7H5O2 ·C7H6O2, the carboxyl and carboxyl­ate groups are twisted away from their attached benzene rings by 10.75 (7) and 20.33 (6)°, respectively. In the crystal structure, the 2,3-diamino­pyridinium cations, benzoate anions and benzoic acid mol­ecules are linked into a two-dimensional network parallel to (001) by O—H(...)O, N—H(...)O and C—H(...)O hydrogen bonds and π–π inter­actions between the pyridinium rings [centroid–centroid distance = 3.4981 (7) Å].

Related literature

For substituted pyridines, see: Pozharski et al. (1997 [triangle]); Katritzky et al. (1996 [triangle]). For related structures, see: Fun & Balasubramani (2009 [triangle]); Balasubramani & Fun (2009a [triangle],b [triangle]). For bond-length data, see: Allen et al. (1987 [triangle]). For details of hydrogen bonding, see: Jeffrey & Saenger (1991 [triangle]); Jeffrey (1997 [triangle]); Scheiner (1997 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o479-scheme1.jpg

Experimental

Crystal data

  • C5H8N3 +·C7H5O2 ·C7H6O2
  • M r = 353.37
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o479-efi1.jpg
  • a = 12.5822 (2) Å
  • b = 11.0826 (1) Å
  • c = 12.5615 (2) Å
  • β = 96.345 (1)°
  • V = 1740.89 (4) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.10 mm−1
  • T = 110 K
  • 0.38 × 0.18 × 0.13 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.964, T max = 0.988
  • 36881 measured reflections
  • 5104 independent reflections
  • 3848 reflections with I > 2σ(I)
  • R int = 0.037

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.111
  • S = 1.05
  • 5104 reflections
  • 259 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.32 e Å−3
  • Δρmin = −0.22 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810001443/ci5016sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810001443/ci5016Isup2.hkl

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

Acknowledgments

MH and HKF thank the Malaysian Government and Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. MH thanks Universiti Sains Malaysia for a post-doctoral research fellowship.

supplementary crystallographic information

Comment

Pyridine and its derivatives play an important role in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). They are often involved in hydrogen-bonding interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). Recently, we have reported crystal structures of 2,3-diaminopyridinium 4-hydroxybenzoate (Fun & Balasubramani, 2009), 2,3-diaminopyridinium 4-nitrobenzoate (Balasubramani & Fun, 2009a) and 2,3-diaminopyridinium benzoate (Balasubramani & Fun, 2009b). In continuation of our studies of pyridinium derivatives, the crystal structure determination of the title compound has been undertaken.

The asymmetric unit of the title compound (Fig. 1), contains a protonated 2,3-diaminopyridinium cation, a benzoate anion and a benzoic acid. In the 2,3-diaminopyridinium cation, a wide angle (124.11 (11)°) is subtented at the protonated N1 atom. The 2,3-diaminopyridinium cation is planar, with a maximum deviation of 0.010 (1) Å for atom C10. The carboxyl and carboxylate groups are twisted away from the attached benzene rings; the dihedral angle between C1B–C6B and O1B/O2B/C6B/C7B planes is 10.75 (7)° and that between C1A–C6A and O1A/O2A/C6A/C7A planes is 20.33 (6)°. The bond lengths (Allen et al. 1987) and angles are normal.

In the crystal (Fig. 2), the protonated N1 atom and the 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O1A and O2A) via a pair of N—H···O hydrogen bonds forming a R22(8) ring motif (Bernstein et al. 1995). The benzoate anion and benzoic acid molecules are connected via O—H···O hydrogen bonds. The crystal structure is further stabilized by π–π stacking interactions between the pyridinium rings at (x, y, z) and (2-x, 1-y, -z), with a ring centroid-to-centroid distance of 3.4981 (7) Å.

Experimental

Hot methanolic solution (10 ml) of 2,3-diaminopyridine (27 mg, Aldrich) and a hot aqueous solution (10 ml) of benzoic acid (31 mg, Merck) were mixed and warmed over a water bath for 10 minutes. The resulting solution was allowed to cool slowly at room temperature. Single crystals of the title compound appreared from the mother liquor after a few days.

Refinement

Atoms H1OB, H1N1, H1N2, H2N2, H1N3 and H2N3 were located in a difference Fourier map and refined freely. The remaining H atoms were positioned geometrically [C–H = 0.93 Å] and were refined using a riding model, with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
Fig. 2.
The crystal packing of the title compound, showing hydrogen-bonded (dashed lines) networks.

Crystal data

C5H8N3+·C7H5O2·C7H6O2F(000) = 744
Mr = 353.37Dx = 1.348 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 9414 reflections
a = 12.5822 (2) Åθ = 2.5–30.0°
b = 11.0826 (1) ŵ = 0.10 mm1
c = 12.5615 (2) ÅT = 110 K
β = 96.345 (1)°Block, orange
V = 1740.89 (4) Å30.38 × 0.18 × 0.13 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer5104 independent reflections
Radiation source: fine-focus sealed tube3848 reflections with I > 2σ(I)
graphiteRint = 0.037
[var phi] and ω scansθmax = 30.1°, θmin = 1.6°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −17→16
Tmin = 0.964, Tmax = 0.988k = −15→15
36881 measured reflectionsl = −17→17

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H atoms treated by a mixture of independent and constrained refinement
S = 1.05w = 1/[σ2(Fo2) + (0.0464P)2 + 0.4367P] where P = (Fo2 + 2Fc2)/3
5104 reflections(Δ/σ)max = 0.001
259 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = −0.22 e Å3

Special details

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 > 2sigma(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
O1A0.85851 (7)0.85383 (8)0.03377 (7)0.0290 (2)
O2A0.95927 (7)0.88574 (8)−0.09759 (6)0.02659 (19)
C1A0.74939 (10)1.07373 (11)−0.01140 (9)0.0281 (3)
H1AA0.74941.04340.05760.034*
C2A0.68601 (11)1.17233 (12)−0.04363 (11)0.0335 (3)
H2AA0.64551.20970.00450.040*
C3A0.68306 (10)1.21522 (12)−0.14752 (11)0.0336 (3)
H3AA0.63931.2801−0.16970.040*
C4A0.74514 (11)1.16156 (13)−0.21788 (10)0.0348 (3)
H4AA0.74261.1899−0.28780.042*
C5A0.81149 (10)1.06528 (11)−0.18501 (9)0.0274 (3)
H5AA0.85491.0312−0.23220.033*
C6A0.81306 (9)1.01987 (10)−0.08187 (8)0.0214 (2)
C7A0.88181 (9)0.91288 (10)−0.04745 (8)0.0222 (2)
N11.05200 (8)0.68618 (9)0.02224 (8)0.0237 (2)
N20.98632 (9)0.70123 (10)0.18620 (9)0.0278 (2)
N31.10673 (10)0.49546 (11)0.25569 (9)0.0336 (3)
C81.04742 (9)0.64369 (10)0.12201 (9)0.0221 (2)
C91.10929 (9)0.53927 (10)0.15432 (9)0.0224 (2)
C101.16824 (9)0.48674 (10)0.08034 (9)0.0244 (2)
H10A1.20800.41770.09920.029*
C111.16949 (10)0.53516 (11)−0.02261 (9)0.0268 (3)
H11A1.21010.4992−0.07140.032*
C121.11068 (10)0.63515 (11)−0.05016 (9)0.0264 (3)
H12A1.11060.6685−0.11810.032*
O1B0.69229 (8)0.72978 (9)0.06840 (7)0.0321 (2)
O2B0.75274 (7)0.77725 (8)0.23701 (7)0.0310 (2)
C1B0.54529 (11)0.56665 (13)0.13724 (12)0.0364 (3)
H1BA0.55780.56370.06570.044*
C2B0.46748 (12)0.49389 (14)0.17377 (15)0.0485 (4)
H2BA0.42810.44170.12670.058*
C3B0.44829 (13)0.49857 (14)0.27941 (15)0.0501 (4)
H3BA0.39530.45030.30330.060*
C4B0.50734 (12)0.57449 (14)0.34983 (13)0.0443 (4)
H4BA0.49430.57710.42120.053*
C5B0.58609 (11)0.64699 (12)0.31465 (10)0.0315 (3)
H5BA0.62640.69750.36250.038*
C6B0.60470 (9)0.64412 (10)0.20783 (9)0.0254 (2)
C7B0.69011 (9)0.72314 (10)0.17338 (9)0.0235 (2)
H1OB0.7482 (18)0.7795 (19)0.0545 (17)0.076 (6)*
H1N11.0151 (13)0.7519 (15)0.0012 (13)0.038 (4)*
H1N20.9746 (13)0.6707 (15)0.2475 (14)0.041 (4)*
H2N20.9452 (13)0.7586 (15)0.1570 (13)0.045 (5)*
H1N31.0666 (13)0.5270 (14)0.3014 (13)0.040 (4)*
H2N31.1455 (13)0.4331 (15)0.2731 (12)0.038 (4)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O1A0.0312 (5)0.0296 (5)0.0266 (4)0.0009 (4)0.0050 (3)0.0098 (3)
O2A0.0266 (4)0.0268 (4)0.0270 (4)0.0029 (3)0.0057 (3)0.0008 (3)
C1A0.0294 (6)0.0309 (6)0.0243 (5)0.0016 (5)0.0045 (5)0.0020 (5)
C2A0.0297 (7)0.0330 (7)0.0385 (7)0.0051 (5)0.0060 (5)−0.0029 (5)
C3A0.0282 (7)0.0274 (6)0.0445 (7)0.0048 (5)0.0010 (5)0.0079 (5)
C4A0.0352 (7)0.0379 (7)0.0312 (6)0.0045 (6)0.0031 (5)0.0145 (5)
C5A0.0282 (6)0.0299 (6)0.0246 (5)0.0014 (5)0.0055 (5)0.0051 (4)
C6A0.0208 (5)0.0208 (5)0.0222 (5)−0.0029 (4)0.0005 (4)0.0019 (4)
C7A0.0241 (6)0.0219 (5)0.0200 (5)−0.0019 (4)0.0000 (4)0.0003 (4)
N10.0254 (5)0.0207 (5)0.0248 (5)0.0020 (4)0.0018 (4)0.0014 (4)
N20.0301 (6)0.0265 (5)0.0280 (5)0.0078 (4)0.0082 (4)0.0024 (4)
N30.0418 (7)0.0340 (6)0.0267 (5)0.0160 (5)0.0113 (5)0.0093 (4)
C80.0212 (5)0.0208 (5)0.0241 (5)−0.0012 (4)0.0019 (4)−0.0005 (4)
C90.0221 (6)0.0214 (5)0.0235 (5)−0.0005 (4)0.0018 (4)0.0006 (4)
C100.0239 (6)0.0212 (6)0.0282 (6)0.0029 (4)0.0029 (4)−0.0003 (4)
C110.0285 (6)0.0280 (6)0.0244 (5)0.0016 (5)0.0060 (5)−0.0029 (4)
C120.0302 (6)0.0279 (6)0.0213 (5)−0.0013 (5)0.0041 (4)0.0008 (4)
O1B0.0342 (5)0.0385 (5)0.0237 (4)−0.0063 (4)0.0036 (4)−0.0013 (4)
O2B0.0313 (5)0.0331 (5)0.0284 (4)−0.0075 (4)0.0031 (4)−0.0048 (4)
C1B0.0311 (7)0.0323 (7)0.0451 (8)−0.0034 (6)0.0011 (6)−0.0051 (6)
C2B0.0355 (8)0.0330 (8)0.0760 (11)−0.0094 (6)0.0020 (8)−0.0029 (7)
C3B0.0364 (8)0.0315 (8)0.0845 (12)−0.0028 (6)0.0156 (8)0.0184 (8)
C4B0.0431 (9)0.0413 (8)0.0510 (9)0.0068 (7)0.0166 (7)0.0208 (7)
C5B0.0324 (7)0.0297 (6)0.0326 (6)0.0034 (5)0.0046 (5)0.0074 (5)
C6B0.0230 (6)0.0207 (5)0.0321 (6)0.0033 (5)0.0017 (5)0.0017 (4)
C7B0.0238 (6)0.0214 (5)0.0253 (5)0.0031 (4)0.0026 (4)−0.0017 (4)

Geometric parameters (Å, °)

O1A—C7A1.2733 (13)C8—C91.4283 (16)
O2A—C7A1.2541 (14)C9—C101.3802 (16)
C1A—C2A1.3866 (18)C10—C111.4018 (16)
C1A—C6A1.3922 (16)C10—H10A0.93
C1A—H1AA0.93C11—C121.3559 (17)
C2A—C3A1.3855 (19)C11—H11A0.93
C2A—H2AA0.93C12—H12A0.93
C3A—C4A1.3775 (19)O1B—C7B1.3241 (14)
C3A—H3AA0.93O1B—H1OB0.93 (2)
C4A—C5A1.3891 (18)O2B—C7B1.2166 (14)
C4A—H4AA0.93C1B—C2B1.385 (2)
C5A—C6A1.3880 (15)C1B—C6B1.3913 (18)
C5A—H5AA0.93C1B—H1BA0.93
C6A—C7A1.5028 (16)C2B—C3B1.376 (2)
N1—C81.3461 (14)C2B—H2BA0.93
N1—C121.3566 (15)C3B—C4B1.377 (2)
N1—H1N10.888 (17)C3B—H3BA0.93
N2—C81.3358 (15)C4B—C5B1.3855 (19)
N2—H1N20.869 (17)C4B—H4BA0.93
N2—H2N20.875 (17)C5B—C6B1.3877 (17)
N3—C91.3665 (15)C5B—H5BA0.93
N3—H1N30.878 (17)C6B—C7B1.4873 (17)
N3—H2N30.860 (17)
C2A—C1A—C6A120.34 (11)N3—C9—C8118.97 (11)
C2A—C1A—H1AA119.8C10—C9—C8117.84 (10)
C6A—C1A—H1AA119.8C9—C10—C11121.42 (11)
C3A—C2A—C1A120.00 (12)C9—C10—H10A119.3
C3A—C2A—H2AA120.0C11—C10—H10A119.3
C1A—C2A—H2AA120.0C12—C11—C10119.13 (11)
C4A—C3A—C2A119.88 (12)C12—C11—H11A120.4
C4A—C3A—H3AA120.1C10—C11—H11A120.4
C2A—C3A—H3AA120.1C11—C12—N1119.45 (11)
C3A—C4A—C5A120.38 (12)C11—C12—H12A120.3
C3A—C4A—H4AA119.8N1—C12—H12A120.3
C5A—C4A—H4AA119.8C7B—O1B—H1OB108.7 (13)
C6A—C5A—C4A120.13 (11)C2B—C1B—C6B119.86 (14)
C6A—C5A—H5AA119.9C2B—C1B—H1BA120.1
C4A—C5A—H5AA119.9C6B—C1B—H1BA120.1
C5A—C6A—C1A119.22 (11)C3B—C2B—C1B120.22 (15)
C5A—C6A—C7A120.19 (10)C3B—C2B—H2BA119.9
C1A—C6A—C7A120.58 (10)C1B—C2B—H2BA119.9
O2A—C7A—O1A122.65 (11)C2B—C3B—C4B120.18 (14)
O2A—C7A—C6A119.96 (10)C2B—C3B—H3BA119.9
O1A—C7A—C6A117.38 (10)C4B—C3B—H3BA119.9
C8—N1—C12124.11 (11)C3B—C4B—C5B120.23 (15)
C8—N1—H1N1119.3 (10)C3B—C4B—H4BA119.9
C12—N1—H1N1116.6 (10)C5B—C4B—H4BA119.9
C8—N2—H1N2121.0 (11)C4B—C5B—C6B119.88 (13)
C8—N2—H2N2116.6 (11)C4B—C5B—H5BA120.1
H1N2—N2—H2N2120.2 (15)C6B—C5B—H5BA120.1
C9—N3—H1N3122.8 (10)C5B—C6B—C1B119.62 (12)
C9—N3—H2N3116.8 (10)C5B—C6B—C7B118.18 (11)
H1N3—N3—H2N3120.3 (14)C1B—C6B—C7B122.19 (11)
N2—C8—N1118.79 (11)O2B—C7B—O1B122.94 (11)
N2—C8—C9123.18 (10)O2B—C7B—C6B122.38 (11)
N1—C8—C9118.03 (10)O1B—C7B—C6B114.68 (10)
N3—C9—C10123.18 (11)
C6A—C1A—C2A—C3A2.2 (2)N3—C9—C10—C11−179.41 (12)
C1A—C2A—C3A—C4A−1.6 (2)C8—C9—C10—C111.28 (17)
C2A—C3A—C4A—C5A−0.6 (2)C9—C10—C11—C12−0.60 (18)
C3A—C4A—C5A—C6A2.1 (2)C10—C11—C12—N10.01 (18)
C4A—C5A—C6A—C1A−1.49 (18)C8—N1—C12—C11−0.18 (18)
C4A—C5A—C6A—C7A177.79 (11)C6B—C1B—C2B—C3B0.4 (2)
C2A—C1A—C6A—C5A−0.64 (18)C1B—C2B—C3B—C4B−0.9 (2)
C2A—C1A—C6A—C7A−179.92 (11)C2B—C3B—C4B—C5B0.3 (2)
C5A—C6A—C7A—O2A20.53 (16)C3B—C4B—C5B—C6B0.7 (2)
C1A—C6A—C7A—O2A−160.20 (11)C4B—C5B—C6B—C1B−1.17 (19)
C5A—C6A—C7A—O1A−160.22 (11)C4B—C5B—C6B—C7B−179.87 (11)
C1A—C6A—C7A—O1A19.05 (16)C2B—C1B—C6B—C5B0.6 (2)
C12—N1—C8—N2−179.66 (11)C2B—C1B—C6B—C7B179.24 (12)
C12—N1—C8—C90.88 (17)C5B—C6B—C7B—O2B9.93 (17)
N2—C8—C9—N3−0.17 (18)C1B—C6B—C7B—O2B−168.74 (12)
N1—C8—C9—N3179.27 (11)C5B—C6B—C7B—O1B−170.02 (11)
N2—C8—C9—C10179.17 (11)C1B—C6B—C7B—O1B11.31 (17)
N1—C8—C9—C10−1.39 (16)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1B—H1OB···O1A0.93 (2)1.66 (2)2.5796 (13)173 (2)
N1—H1N1···O1A0.89 (2)2.35 (2)3.0786 (13)140 (1)
N1—H1N1···O2A0.89 (2)2.01 (2)2.8514 (13)158 (2)
N2—H1N2···O2Ai0.87 (2)2.07 (2)2.9370 (14)173 (2)
N2—H2N2···O1A0.87 (2)2.08 (2)2.9038 (14)157 (2)
N3—H1N3···O2Ai0.88 (2)2.18 (2)3.0543 (15)175 (2)
N3—H2N3···O1Aii0.86 (2)2.59 (2)3.0649 (14)116 (1)
N3—H2N3···O2Bii0.86 (2)2.16 (2)2.9912 (15)162 (1)
C10—H10A···O2Bii0.932.583.3375 (14)138

Symmetry codes: (i) x, −y+3/2, z+1/2; (ii) −x+2, y−1/2, −z+1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI5016).

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