organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 68| Part 5| May 2012| Page o1524

Bis(2-amino­pyridinium) 2,5-dicarb­­oxy­benzene-1,4-di­carboxyl­ate

aCEMDRX, Department of Physics, University of Coimbra, P-3004-516 Coimbra, Portugal, and bDepartment of Chemistry, Payame Noor University, 19395-4697 Tehran, Iran
*Correspondence e-mail: vhugo@fis.uc.pt

(Received 16 April 2012; accepted 18 April 2012; online 25 April 2012)

In the title compound, 2C5H7N2+·C10H4O82−, the 2-amino­pyridinium (2-apyH) cation and 2,5-dicarb­oxy­benzene-1,4-dicarboxyl­ate (btcH2) anion are both nearly planar, with r.m.s. deviations of 0.015 and 0.050 Å, respectively. The angle between the latter least-squares planes is 17.68 (9)°. The overall crystal structure results from the packing of two-dimensional networks, formed by alternating 2-apyH and btcH2 linked by hydrogen bonds, parallel to (100).

Related literature

For similar and most common conformations of 2-amino­pyridinium, see: Guelmami & Jouini (2011[Guelmami, L. & Jouini, A. (2011). J. Chem. Crystallogr. 41, 1268-1272.]); Chitra et al. (2008[Chitra, R., Roussel, P., Capet, F., Murli, C. & Choudhury, R. R. (2008). J. Mol. Struct. 891, 103-109.]); Quah et al. (2008[Quah, C. K., Jebas, S. R. & Fun, H.-K. (2008). Acta Cryst. E64, o2230.]); Bis & Zaworotko (2005[Bis, J. A. & Zaworotko, M. J. (2005). Cryst. Growth Des. 5, 1169-1179.]); Büyükgüngör & Odabas˛ogˇlu (2002[Büyükgüngör, O. & Odabas˛ogˇlu, M. (2002). Acta Cryst. C58, o691-o692.]); Odabas˛ogˇlu et al. (2003[Odabasoglu, M., Büyükgüngör, O., Turgut, G., Karadag, A., Bulak, E. & Lönneçke, P. (2003). J. Mol. Struct. 648, 133-138.]); Acheson (1967[Acheson, R. M. (1967). An Introduction to the Chemistry of Heterocyclic Compounds, 2nd ed., pp. 215-218. London: Wiley.]). For similar and most common conformations of 2,5-dicarb­oxy­benzene-1,4-dicarboxyl­ate, see: Dong et al. (2011[Dong, G.-Y., Liu, T.-F., He, C.-H., Deng, X.-C. & Shi, X.-G. (2011). Acta Cryst. E67, o1696.]); Wang & Tang (2010[Wang, Y.-J. & Tang, L.-M. (2010). Chin. J. Struct. Chem. 29, 102-108.]). For graph-set analysis of hydrogen-bond patterns in organic crystals, see: Etter et al. (1990[Etter, M. C., MacDonald, J. C. & Bernstein, J. (1990). Acta Cryst. B46, 256-262.]).

[Scheme 1]

Experimental

Crystal data
  • 2C5H7N2+·C10H4O82−

  • Mr = 442.38

  • Monoclinic, P 21 /c

  • a = 4.0165 (1) Å

  • b = 10.8098 (4) Å

  • c = 21.4036 (7) Å

  • β = 99.535 (2)°

  • V = 916.45 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.13 mm−1

  • T = 273 K

  • 0.3 × 0.2 × 0.15 mm

Data collection
  • Bruker–Nonius APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2003[Sheldrick, G. M. (2003). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.755, Tmax = 1.000

  • 18838 measured reflections

  • 2209 independent reflections

  • 1652 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.037

  • wR(F2) = 0.102

  • S = 1.01

  • 2209 reflections

  • 158 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.15 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1A⋯O2 0.913 (16) 1.904 (17) 2.7852 (15) 161.6 (15)
N1—H1A⋯O1 0.913 (16) 2.478 (16) 3.2413 (16) 141.4 (13)
N2—H2A⋯O3i 0.831 (19) 2.125 (19) 2.9520 (17) 173.0 (17)
N2—H2B⋯O1 0.880 (19) 2.14 (2) 2.9759 (17) 157.6 (16)
O4—H4A⋯O1 1.06 (2) 1.31 (2) 2.3766 (15) 176.8 (17)
Symmetry code: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker–Nonius, 2004[Bruker-Nonius (2004). APEX2. Bruker-Nonius BV, Delft, The Netherlands.]); cell refinement: SAINT (Bruker, 2003[Bruker (2003). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

This work is a further contribution to the broad family of structural studies of 2-aminopyridinium (2-apyH) systems with hydrogen-bond donors. A considerable number of analogous materials formed from 2-aminopyridine and a given carboxylic acid has already been reported (Guelmami & Jouini, 2011; Chitra et al., 2008; Quah et al., 2008; Bis & Zaworotko, 2005; Büyükgüngör & Odabas˛ogˇlu, 2002; Odabas˛ogˇlu et al., 2003; etc). This is due to the fact that 2-aminopyridine is protonated in acidic solutions. It is well known that the bonding of the H atom to the ring N atom of 2-aminopyridine, and not to the amino N atom, produces an ion for which an additional resonance structure must be considered (Acheson, 1967). We have inferred the positive charge in the 2-apyH ion lies on the amino group based on a difference fourier map, a common practice when allowed by the quality of the collected intensities. The charge state, related to the hydrogen loss, in each of the two candidate carboxylic acid groups belonging to the assymetric unit was also inferred from a difference map and further reinforced by analysis of the C–O bond lengths.

Ellucidation of the numbering scheme and a view of the H-bonds giving rise to two-dimensional networks parallel to (100) are shown in Figs. 1 and 2, respectively. Both the 2-apyH cation and 2,5-dicarboxybenzene-1,4-dicarboxylate (btcH2) anion are nearly planar, with r.m.s. deviations of 0.015 and 0.050 A, respectively. The angle between the latter idealized planes is 17.68 (9)°. The two-dimensional networks are formed by alternating 2-apyH and btcH2 linked by H-bonds and include all H-bonds found. The first order network describing the H-bonding in the title compound is N1=4DS(7), as established by applying the rules of graph-set analysis of hydrogen-bond patterns in organic crystals (Etter et al., 1990).

Similar and most common conformations of 2,5-dicarboxybenzene-1,4-dicarboxylate were described by Dong et al. (2011) and Wang & Tang (2010).

Related literature top

For similar and most common conformations of 2-aminopyridinium, see: Guelmami & Jouini (2011); Chitra et al. (2008); Quah et al. (2008); Bis & Zaworotko (2005); Büyükgüngör & Odabas˛ogˇlu (2002); Odabas˛ogˇlu et al. (2003); Acheson (1967). For similar and most common conformations of 2,5-dicarboxybenzene-1,4-dicarboxylate, see: Dong et al. (2011); Wang & Tang (2010). For graph-set analysis of hydrogen-bond patterns in organic crystals, see: Etter et al. (1990).

Experimental top

A solution of 0.254 g (1 mmol) benzene-1,2,4,5-tetracarboxylicacid in methanol (10 ml) was added to a solution of 2-aminopyridine (0.1 g, 1 mmol) in water (15 ml), and refluxed for 1 h. The resulting solution was light yellow in colour. After slow evaporation of the solvent at room-temperature colorless prisms of the compound were obtained.

Refinement top

The structure was solved by direct methods using SHELXS97 (Sheldrick, 2008). H atoms bound to aromatic C were placed at idealized positions and refined as riding, with C—H=0.93 (Sheldrick, 2008); amine and carboxyl H atoms were found from a difference fourier map and their coordinates refined freely. Uiso(H) was fixed to 1.2 times Ueq of the heavy atom they are bonded to, for all hydrogen atoms.

Examination of the crystal structure with PLATON (Spek, 2009) showed that there are no solvent-accessible voids in the crystal lattice.

Computing details top

Data collection: APEX2 (Bruker–Nonius, 2004); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEPII plot of the title compound. Displacement ellipsoids are drawn at the 50% level.
[Figure 2] Fig. 2. Representation of the two-dimensional networks, paralell to the (100) planes, of H-bonded molecules.
Bis(2-aminopyridinium) 2,5-dicarboxybenzene-1,4-dicarboxylate top
Crystal data top
2C5H7N2+·C10H4O82F(000) = 460
Mr = 442.38Dx = 1.603 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 7209 reflections
a = 4.0165 (1) Åθ = 2.7–24.9°
b = 10.8098 (4) ŵ = 0.13 mm1
c = 21.4036 (7) ÅT = 273 K
β = 99.535 (2)°Block, yellow
V = 916.45 (5) Å30.3 × 0.2 × 0.15 mm
Z = 2
Data collection top
Bruker–Nonius APEXII CCD area-detector
diffractometer
2209 independent reflections
Radiation source: fine-focus sealed tube1652 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
ϕ and ω scansθmax = 28.2°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
h = 45
Tmin = 0.755, Tmax = 1.000k = 1314
18838 measured reflectionsl = 2723
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.037H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.102 w = 1/[σ2(Fo2) + (0.0519P)2 + 0.1584P]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max < 0.001
2209 reflectionsΔρmax = 0.20 e Å3
158 parametersΔρmin = 0.15 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.014 (3)
Crystal data top
2C5H7N2+·C10H4O82V = 916.45 (5) Å3
Mr = 442.38Z = 2
Monoclinic, P21/cMo Kα radiation
a = 4.0165 (1) ŵ = 0.13 mm1
b = 10.8098 (4) ÅT = 273 K
c = 21.4036 (7) Å0.3 × 0.2 × 0.15 mm
β = 99.535 (2)°
Data collection top
Bruker–Nonius APEXII CCD area-detector
diffractometer
2209 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003)
1652 reflections with I > 2σ(I)
Tmin = 0.755, Tmax = 1.000Rint = 0.024
18838 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.102H atoms treated by a mixture of independent and constrained refinement
S = 1.01Δρmax = 0.20 e Å3
2209 reflectionsΔρmin = 0.15 e Å3
158 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N11.1547 (3)0.04940 (11)0.38178 (5)0.0424 (3)
H1A1.040 (4)0.1095 (15)0.3993 (8)0.051*
C11.1679 (3)0.04905 (12)0.32019 (6)0.0370 (3)
N21.0229 (4)0.14007 (12)0.28496 (6)0.0511 (3)
H2A1.021 (4)0.1363 (16)0.2461 (9)0.061*
H2B0.916 (5)0.1990 (16)0.3019 (9)0.061*
C31.3390 (4)0.04878 (13)0.29700 (7)0.0469 (4)
H31.35080.05320.25400.056*
C41.4882 (4)0.13741 (15)0.33704 (9)0.0569 (4)
H41.60420.20190.32150.068*
C51.4684 (4)0.13228 (16)0.40058 (9)0.0587 (4)
H51.57120.19220.42850.070*
C61.2984 (4)0.03922 (15)0.42096 (7)0.0523 (4)
H61.27860.03560.46360.063*
C70.7030 (3)0.40755 (11)0.52514 (6)0.0325 (3)
H70.84440.34400.54270.039*
C80.5869 (3)0.40386 (11)0.46123 (5)0.0312 (3)
C90.7148 (3)0.29317 (12)0.42838 (6)0.0380 (3)
O10.6529 (3)0.28618 (10)0.36938 (5)0.0588 (3)
O20.8806 (3)0.21344 (9)0.45984 (5)0.0591 (3)
C100.3760 (3)0.50071 (11)0.43487 (5)0.0315 (3)
C110.2130 (3)0.52081 (12)0.36717 (6)0.0386 (3)
O30.0283 (3)0.60888 (10)0.35332 (5)0.0571 (3)
O40.2721 (3)0.44339 (10)0.32502 (4)0.0556 (3)
H4A0.448 (5)0.3738 (17)0.3439 (8)0.067*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0464 (7)0.0473 (7)0.0338 (6)0.0050 (5)0.0072 (5)0.0078 (5)
C10.0391 (7)0.0395 (7)0.0316 (7)0.0064 (5)0.0038 (5)0.0049 (5)
N20.0690 (9)0.0481 (7)0.0339 (6)0.0058 (6)0.0017 (6)0.0040 (6)
C30.0463 (8)0.0510 (9)0.0452 (8)0.0037 (7)0.0129 (6)0.0118 (7)
C40.0450 (8)0.0447 (8)0.0820 (12)0.0006 (7)0.0131 (8)0.0058 (8)
C50.0511 (9)0.0552 (9)0.0664 (11)0.0078 (7)0.0001 (8)0.0187 (8)
C60.0516 (9)0.0648 (10)0.0387 (8)0.0144 (8)0.0025 (7)0.0090 (7)
C70.0367 (6)0.0310 (6)0.0303 (6)0.0027 (5)0.0067 (5)0.0019 (5)
C80.0349 (6)0.0316 (6)0.0284 (6)0.0069 (5)0.0091 (5)0.0015 (5)
C90.0437 (7)0.0364 (7)0.0351 (7)0.0050 (6)0.0102 (6)0.0056 (5)
O10.0832 (8)0.0600 (7)0.0336 (6)0.0173 (6)0.0113 (5)0.0114 (5)
O20.0841 (8)0.0469 (6)0.0453 (6)0.0203 (6)0.0074 (5)0.0048 (5)
C100.0358 (6)0.0336 (6)0.0259 (6)0.0087 (5)0.0069 (5)0.0005 (5)
C110.0451 (7)0.0429 (7)0.0275 (6)0.0065 (6)0.0055 (5)0.0006 (5)
O30.0777 (7)0.0550 (7)0.0336 (6)0.0151 (6)0.0053 (5)0.0017 (4)
O40.0763 (8)0.0634 (7)0.0257 (5)0.0096 (6)0.0045 (5)0.0065 (5)
Geometric parameters (Å, º) top
N1—C11.3281 (17)C6—H60.9300
N1—C61.3392 (19)C7—C81.3707 (17)
N1—H1A0.913 (16)C7—C10i1.3809 (17)
C1—N21.3154 (19)C7—H70.9300
C1—C31.3964 (19)C8—C101.4049 (18)
N2—H2A0.831 (19)C8—C91.5197 (17)
N2—H2B0.880 (19)C9—O21.2212 (16)
C3—C41.357 (2)C9—O11.2483 (16)
C3—H30.9300C10—C7i1.3809 (17)
C4—C51.377 (2)C10—C111.5037 (17)
C4—H40.9300C11—O31.2133 (17)
C5—C61.329 (2)C11—O41.2811 (16)
C5—H50.9300O4—H4A1.06 (2)
C1—N1—C6122.39 (13)C5—C6—H6119.1
C1—N1—H1A121.0 (10)N1—C6—H6119.1
C6—N1—H1A116.6 (10)C8—C7—C10i124.36 (12)
N2—C1—N1118.70 (13)C8—C7—H7117.8
N2—C1—C3124.06 (13)C10i—C7—H7117.8
N1—C1—C3117.24 (13)C7—C8—C10117.52 (11)
C1—N2—H2A117.8 (12)C7—C8—C9113.54 (11)
C1—N2—H2B120.4 (12)C10—C8—C9128.93 (11)
H2A—N2—H2B121.5 (17)O2—C9—O1120.93 (12)
C4—C3—C1120.15 (14)O2—C9—C8119.73 (11)
C4—C3—H3119.9O1—C9—C8119.33 (12)
C1—C3—H3119.9C7i—C10—C8118.12 (11)
C3—C4—C5120.25 (15)C7i—C10—C11112.67 (11)
C3—C4—H4119.9C8—C10—C11129.20 (11)
C5—C4—H4119.9O3—C11—O4121.18 (12)
C6—C5—C4118.13 (15)O3—C11—C10119.99 (12)
C6—C5—H5120.9O4—C11—C10118.83 (12)
C4—C5—H5120.9C11—O4—H4A112.5 (9)
C5—C6—N1121.83 (15)
C6—N1—C1—N2179.42 (13)C10—C8—C9—O2175.39 (13)
C6—N1—C1—C30.14 (19)C7—C8—C9—O1173.10 (12)
N2—C1—C3—C4178.46 (14)C10—C8—C9—O15.7 (2)
N1—C1—C3—C41.1 (2)C7—C8—C10—C7i0.56 (18)
C1—C3—C4—C50.8 (2)C9—C8—C10—C7i179.36 (11)
C3—C4—C5—C60.5 (2)C7—C8—C10—C11179.96 (11)
C4—C5—C6—N11.4 (2)C9—C8—C10—C111.2 (2)
C1—N1—C6—C51.1 (2)C7i—C10—C11—O31.71 (17)
C10i—C7—C8—C100.60 (19)C8—C10—C11—O3177.72 (13)
C10i—C7—C8—C9179.58 (11)C7i—C10—C11—O4178.55 (12)
C7—C8—C9—O25.76 (17)C8—C10—C11—O42.01 (19)
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O20.913 (16)1.904 (17)2.7852 (15)161.6 (15)
N1—H1A···O10.913 (16)2.478 (16)3.2413 (16)141.4 (13)
N2—H2A···O3ii0.831 (19)2.125 (19)2.9520 (17)173.0 (17)
N2—H2B···O10.880 (19)2.14 (2)2.9759 (17)157.6 (16)
O4—H4A···O11.06 (2)1.31 (2)2.3766 (15)176.8 (17)
Symmetry code: (ii) x+1, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formula2C5H7N2+·C10H4O82
Mr442.38
Crystal system, space groupMonoclinic, P21/c
Temperature (K)273
a, b, c (Å)4.0165 (1), 10.8098 (4), 21.4036 (7)
β (°) 99.535 (2)
V3)916.45 (5)
Z2
Radiation typeMo Kα
µ (mm1)0.13
Crystal size (mm)0.3 × 0.2 × 0.15
Data collection
DiffractometerBruker–Nonius APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2003)
Tmin, Tmax0.755, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
18838, 2209, 1652
Rint0.024
(sin θ/λ)max1)0.666
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.102, 1.01
No. of reflections2209
No. of parameters158
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.20, 0.15

Computer programs: APEX2 (Bruker–Nonius, 2004), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O20.913 (16)1.904 (17)2.7852 (15)161.6 (15)
N1—H1A···O10.913 (16)2.478 (16)3.2413 (16)141.4 (13)
N2—H2A···O3i0.831 (19)2.125 (19)2.9520 (17)173.0 (17)
N2—H2B···O10.880 (19)2.14 (2)2.9759 (17)157.6 (16)
O4—H4A···O11.06 (2)1.31 (2)2.3766 (15)176.8 (17)
Symmetry code: (i) x+1, y1/2, z+1/2.
 

Acknowledgements

This work was supported by funds from FEDER via the COMPETE (Programa Operacional Factores de Competitividade) programme and by the FCT (Fundação para a Ciência e a Tecnologia) (project PEst-C/FIS/UI0036/2011).

References

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Volume 68| Part 5| May 2012| Page o1524
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