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2-Amino-5-methyl­pyridinium 4-nitro­benzoate

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 8 February 2010; accepted 9 February 2010; online 13 February 2010)

In the title compound, C6H9N2+·C7H4NO4, the nitro group of the 4-nitro­benzoate anion is twisted by 6.2 (2)° from the attached ring. In the crystal structure, the cations and anions are linked via strong N—H⋯O and weak C—H⋯O hydrogen bonds, forming a three-dimensional network.

Related literature

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997[Pozharski, A. F., Soldatenkov, A. T. & Katritzky, A. R. (1997). Heterocycles in Life and Society. New York: Wiley.]); Katritzky et al. (1996[Katritzky, A. R., Rees, C. W. & Scriven, E. F. V. (1996). Comprehensive Heterocyclic Chemistry II. Oxford: Pergamon Press.]); Hemamalini & Fun (2010[Hemamalini, M. & Fun, H.-K. (2010). Acta Cryst. E66, o335.]). For details of hydrogen bonding, see: Jeffrey & Saenger (1991[Jeffrey, G. A. & Saenger, W. (1991). Hydrogen Bonding in Biological Structures. Berlin: Springer.]); Jeffrey (1997[Jeffrey, G. A. (1997). An Introduction to Hydrogen Bonding. Oxford University Press.]); Scheiner (1997[Scheiner, S. (1997). Hydrogen Bonding. A Theoretical Perspective. Oxford University Press.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C6H9N2+·C7H4NO4

  • Mr = 275.26

  • Monoclinic, P c

  • a = 13.684 (12) Å

  • b = 4.025 (4) Å

  • c = 12.706 (11) Å

  • β = 114.94 (2)°

  • V = 634.5 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 100 K

  • 0.36 × 0.18 × 0.08 mm

Data collection
  • Bruker APEX DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.961, Tmax = 0.991

  • 7053 measured reflections

  • 1854 independent reflections

  • 1283 reflections with I > 2σ(I)

  • Rint = 0.042

Refinement
  • R[F2 > 2σ(F2)] = 0.045

  • wR(F2) = 0.116

  • S = 1.06

  • 1854 reflections

  • 222 parameters

  • 2 restraints

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

  • Δρmax = 0.19 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O3i 0.97 (5) 2.47 (4) 3.238 (5) 136 (3)
N1—H1N1⋯O4i 0.97 (5) 1.77 (5) 2.711 (4) 163 (3)
N2—H1N2⋯O4ii 0.89 (4) 2.02 (4) 2.905 (4) 179 (5)
N2—H2N2⋯O3i 0.91 (4) 1.92 (4) 2.804 (5) 165 (4)
C3—H3A⋯O1iii 0.93 (4) 2.58 (4) 3.514 (6) 176 (3)
Symmetry codes: (i) x, y-1, z; (ii) [x, -y+1, z-{\script{1\over 2}}]; (iii) x+1, y+1, z.

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

Supporting information


Comment top

Pyridine and its derivatives play important roles in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). They are often involved in hydrogen-bond interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). We have recently reported the crystal structure of 2-amino-4-methylpyridinium 4-nitrobenzoate (Hemamalini & Fun, 2010). In a continuation of our studies of pyridinium derivatives, the crystal structure of title compound is presented here.

The asymmetric unit of the title compound (Fig 1), contains a protonated 2-amino-5-methylpyridinium cation and a 4-nitrobenzoate anion. In the 4-nitrobenzoate anion, the nitro group is twisted slightly from the ring with the dihedral angle between O1/O2/N3/C9 and C7–C12 planes being 6.2 (2)°. In the 2-amino-5-methylpyridinium cation, a wide angle (122.0 (3)°) is subtended at the protonated N1 atom. The 2-amino-5-methylpyridinium cation is planar, with a maximum deviation of 0.015 (4)Å for atom C2. The bond lengths are normal (Allen et al., 1987).

In the crystal (Fig. 2), the protonated N1 atom and the 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O3 and O4) via a pair of N—H···O hydrogen bonds forming an R22(8) ring motif (Bernstein et al., 1995). Bifurcated hydrogen bonds are observed between the carboxylate oxygen atoms (O3 & O4) and the protonated N atom to form a four-membered R12(4) hydrogen-bonded ring. The crystal structure is further stabilized by weak C—H···O (Table 1) hydrogen bonds to form a three-dimensional network.

Related literature top

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996); Hemamalini & Fun (2010). For details of hydrogen bonding, see: Jeffrey & Saenger (1991); Jeffrey (1997); Scheiner (1997). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

A hot methanol solution (20 ml) of 2-amino-5-methylpyridine (27 mg, Aldrich) and 4-nitrobenzoic acid (42 mg, Merck) were mixed and warmed over a heating magnetic stirrer for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound appeared after a few days.

Refinement top

The methyl H atoms were positioned geometrically and were refined using a riding model, with Uiso(H) = 1.5Ueq(C). A rotating group model was used for the methyl group. The remaining H atoms were located in a difference map and refined freely [N–H = 0.89 (4)–0.97 (4)Å and C–H = 0.89 (4)–0.98 (4)Å]. In the absence of significant anomalous scattering effects, 1641 Friedel pairs were merged.

Computing details top

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

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the title compound, showing hydrogen-bonded (dashed lines) networks.
2-Amino-5-methylpyridinium 4-nitrobenzoate top
Crystal data top
C6H9N2+·C7H4NO4F(000) = 288
Mr = 275.26Dx = 1.441 Mg m3
Monoclinic, PcMo Kα radiation, λ = 0.71073 Å
Hall symbol: P -2ycCell parameters from 1854 reflections
a = 13.684 (12) Åθ = 3.2–28.2°
b = 4.025 (4) ŵ = 0.11 mm1
c = 12.706 (11) ÅT = 100 K
β = 114.94 (2)°Block, colourless
V = 634.5 (10) Å30.36 × 0.18 × 0.08 mm
Z = 2
Data collection top
Bruker APEX DUO CCD area-detector
diffractometer
1854 independent reflections
Radiation source: fine-focus sealed tube1283 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.042
ϕ and ω scansθmax = 30.0°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1819
Tmin = 0.961, Tmax = 0.991k = 55
7053 measured reflectionsl = 1717
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0604P)2]
where P = (Fo2 + 2Fc2)/3
1854 reflections(Δ/σ)max < 0.001
222 parametersΔρmax = 0.19 e Å3
2 restraintsΔρmin = 0.20 e Å3
Crystal data top
C6H9N2+·C7H4NO4V = 634.5 (10) Å3
Mr = 275.26Z = 2
Monoclinic, PcMo Kα radiation
a = 13.684 (12) ŵ = 0.11 mm1
b = 4.025 (4) ÅT = 100 K
c = 12.706 (11) Å0.36 × 0.18 × 0.08 mm
β = 114.94 (2)°
Data collection top
Bruker APEX DUO CCD area-detector
diffractometer
1854 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1283 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.991Rint = 0.042
7053 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0452 restraints
wR(F2) = 0.116H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.19 e Å3
1854 reflectionsΔρmin = 0.20 e Å3
222 parameters
Special details top

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 s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
N10.83203 (19)0.0861 (6)0.16111 (18)0.0407 (6)
N20.7398 (2)0.0221 (8)0.0369 (2)0.0498 (7)
C10.8230 (2)0.1476 (7)0.0532 (2)0.0399 (7)
C20.9053 (3)0.3372 (8)0.0431 (3)0.0489 (8)
C30.9897 (3)0.4449 (9)0.1392 (3)0.0508 (8)
C40.9979 (3)0.3777 (7)0.2514 (3)0.0459 (7)
C50.9169 (2)0.1971 (8)0.2569 (3)0.0429 (7)
C61.0921 (3)0.4935 (10)0.3582 (3)0.0653 (9)
H6A1.07810.45400.42510.098*
H6B1.10300.72690.35190.098*
H6C1.15550.37390.36620.098*
O10.1957 (2)0.0891 (11)0.1134 (2)0.0995 (12)
O20.2751 (3)0.0198 (10)0.2954 (3)0.0953 (11)
O30.61995 (19)0.6210 (7)0.04604 (18)0.0613 (7)
O40.70099 (15)0.7415 (6)0.23282 (17)0.0504 (5)
N30.2718 (2)0.0063 (7)0.1991 (2)0.0548 (7)
C70.5306 (2)0.4378 (8)0.2704 (2)0.0401 (6)
C80.4456 (2)0.2895 (8)0.2828 (2)0.0428 (6)
C90.3641 (2)0.1565 (7)0.1870 (2)0.0400 (6)
C100.3648 (3)0.1575 (8)0.0790 (3)0.0470 (7)
C110.4522 (2)0.3019 (8)0.0683 (2)0.0443 (7)
C120.5345 (2)0.4473 (7)0.1622 (2)0.0339 (5)
C130.6260 (2)0.6165 (7)0.1462 (2)0.0401 (7)
H2A0.896 (2)0.396 (9)0.035 (3)0.048 (8)*
H3A1.042 (3)0.577 (9)0.131 (3)0.059 (10)*
H5A0.915 (3)0.145 (9)0.328 (3)0.055 (9)*
H7A0.585 (2)0.545 (7)0.333 (2)0.034 (7)*
H9A0.442 (3)0.273 (8)0.355 (4)0.061 (10)*
H10A0.308 (3)0.083 (10)0.017 (3)0.065 (11)*
H11A0.459 (3)0.323 (10)0.006 (4)0.070 (11)*
H1N10.775 (4)0.035 (9)0.171 (3)0.059 (10)*
H1N20.728 (3)0.097 (9)0.107 (3)0.052 (9)*
H2N20.691 (3)0.087 (9)0.019 (3)0.055 (10)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0419 (14)0.0442 (13)0.0410 (12)0.0003 (11)0.0224 (11)0.0046 (11)
N20.0518 (16)0.0608 (17)0.0392 (13)0.0021 (13)0.0217 (12)0.0057 (12)
C10.0431 (16)0.0395 (16)0.0406 (14)0.0106 (12)0.0211 (13)0.0076 (12)
C20.061 (2)0.0446 (17)0.0533 (17)0.0047 (14)0.0356 (16)0.0118 (14)
C30.0485 (19)0.0460 (18)0.064 (2)0.0025 (15)0.0299 (16)0.0072 (15)
C40.0455 (17)0.0389 (15)0.0514 (16)0.0041 (13)0.0186 (14)0.0031 (14)
C50.0444 (16)0.0457 (16)0.0393 (15)0.0034 (13)0.0183 (13)0.0043 (13)
C60.052 (2)0.064 (2)0.066 (2)0.0083 (17)0.0123 (16)0.0025 (17)
O10.069 (2)0.162 (3)0.0674 (18)0.061 (2)0.0293 (16)0.0244 (19)
O20.090 (2)0.152 (3)0.0620 (17)0.046 (2)0.0490 (17)0.0059 (18)
O30.0633 (15)0.0915 (18)0.0378 (11)0.0184 (13)0.0299 (11)0.0033 (12)
O40.0455 (12)0.0696 (14)0.0406 (11)0.0138 (11)0.0224 (9)0.0070 (10)
N30.0509 (16)0.0659 (18)0.0539 (16)0.0126 (14)0.0283 (13)0.0038 (14)
C70.0454 (16)0.0462 (16)0.0284 (12)0.0042 (13)0.0151 (12)0.0026 (11)
C80.0498 (17)0.0510 (18)0.0330 (13)0.0057 (14)0.0227 (12)0.0005 (12)
C90.0410 (16)0.0405 (16)0.0424 (15)0.0001 (11)0.0216 (13)0.0031 (12)
C100.0476 (18)0.0576 (19)0.0325 (14)0.0095 (15)0.0135 (13)0.0051 (13)
C110.0524 (18)0.0542 (19)0.0305 (13)0.0037 (14)0.0216 (13)0.0002 (12)
C120.0377 (14)0.0360 (14)0.0297 (11)0.0035 (10)0.0160 (10)0.0013 (10)
C130.0445 (17)0.0470 (16)0.0330 (14)0.0004 (13)0.0203 (12)0.0017 (11)
Geometric parameters (Å, º) top
N1—C11.347 (3)O1—N31.208 (4)
N1—C51.355 (4)O2—N31.210 (4)
N1—H1N10.97 (4)O3—C131.241 (3)
N2—C11.328 (4)O4—C131.251 (3)
N2—H1N20.89 (4)N3—C91.466 (4)
N2—H2N20.90 (4)C7—C81.374 (4)
C1—C21.410 (4)C7—C121.399 (4)
C2—C31.350 (5)C7—H7A0.94 (3)
C2—H2A0.97 (3)C8—C91.366 (4)
C3—C41.408 (5)C8—H9A0.94 (4)
C3—H3A0.94 (4)C9—C101.375 (4)
C4—C51.352 (5)C10—C111.387 (5)
C4—C61.499 (5)C10—H10A0.89 (4)
C5—H5A0.93 (4)C11—C121.379 (4)
C6—H6A0.9600C11—H11A0.98 (4)
C6—H6B0.9600C12—C131.512 (4)
C6—H6C0.9600
C1—N1—C5122.0 (3)H6B—C6—H6C109.5
C1—N1—H1N1119 (2)O1—N3—O2122.2 (3)
C5—N1—H1N1119 (2)O1—N3—C9119.3 (3)
C1—N2—H1N2117 (2)O2—N3—C9118.4 (3)
C1—N2—H2N2115 (2)C8—C7—C12120.6 (3)
H1N2—N2—H2N2125 (3)C8—C7—H7A121.1 (18)
N2—C1—N1119.0 (3)C12—C7—H7A118.2 (18)
N2—C1—C2123.7 (3)C9—C8—C7118.7 (3)
N1—C1—C2117.2 (3)C9—C8—H9A118 (2)
C3—C2—C1120.2 (3)C7—C8—H9A123 (2)
C3—C2—H2A122.6 (19)C8—C9—C10122.8 (3)
C1—C2—H2A117.1 (19)C8—C9—N3118.9 (2)
C2—C3—C4121.7 (3)C10—C9—N3118.3 (3)
C2—C3—H3A119 (2)C9—C10—C11117.9 (3)
C4—C3—H3A119 (2)C9—C10—H10A120 (2)
C5—C4—C3116.0 (3)C11—C10—H10A122 (2)
C5—C4—C6122.1 (3)C12—C11—C10121.1 (3)
C3—C4—C6121.8 (3)C12—C11—H11A115 (2)
C4—C5—N1122.8 (3)C10—C11—H11A124 (2)
C4—C5—H5A122 (2)C11—C12—C7118.9 (3)
N1—C5—H5A116 (2)C11—C12—C13119.7 (2)
C4—C6—H6A109.5C7—C12—C13121.4 (2)
C4—C6—H6B109.5O3—C13—O4124.8 (3)
H6A—C6—H6B109.5O3—C13—C12116.3 (2)
C4—C6—H6C109.5O4—C13—C12118.8 (2)
H6A—C6—H6C109.5
C5—N1—C1—N2177.7 (3)O2—N3—C9—C86.1 (5)
C5—N1—C1—C20.7 (4)O1—N3—C9—C105.5 (5)
N2—C1—C2—C3177.3 (3)O2—N3—C9—C10173.9 (3)
N1—C1—C2—C31.1 (4)C8—C9—C10—C110.3 (5)
C1—C2—C3—C41.0 (5)N3—C9—C10—C11179.6 (3)
C2—C3—C4—C50.6 (5)C9—C10—C11—C121.6 (5)
C2—C3—C4—C6179.3 (3)C10—C11—C12—C72.1 (4)
C3—C4—C5—N10.2 (5)C10—C11—C12—C13177.2 (3)
C6—C4—C5—N1178.9 (3)C8—C7—C12—C110.8 (4)
C1—N1—C5—C40.3 (4)C8—C7—C12—C13178.5 (3)
C12—C7—C8—C91.1 (4)C11—C12—C13—O31.7 (4)
C7—C8—C9—C101.6 (5)C7—C12—C13—O3177.6 (3)
C7—C8—C9—N3178.3 (3)C11—C12—C13—O4178.7 (3)
O1—N3—C9—C8174.4 (4)C7—C12—C13—O42.1 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O3i0.97 (5)2.47 (4)3.238 (5)136 (3)
N1—H1N1···O4i0.97 (5)1.77 (5)2.711 (4)163 (3)
N2—H1N2···O4ii0.89 (4)2.02 (4)2.905 (4)179 (5)
N2—H2N2···O3i0.91 (4)1.92 (4)2.804 (5)165 (4)
C3—H3A···O1iii0.93 (4)2.58 (4)3.514 (6)176 (3)
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z1/2; (iii) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C7H4NO4
Mr275.26
Crystal system, space groupMonoclinic, Pc
Temperature (K)100
a, b, c (Å)13.684 (12), 4.025 (4), 12.706 (11)
β (°) 114.94 (2)
V3)634.5 (10)
Z2
Radiation typeMo Kα
µ (mm1)0.11
Crystal size (mm)0.36 × 0.18 × 0.08
Data collection
DiffractometerBruker APEX DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.961, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
7053, 1854, 1283
Rint0.042
(sin θ/λ)max1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.116, 1.06
No. of reflections1854
No. of parameters222
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.19, 0.20

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O3i0.97 (5)2.47 (4)3.238 (5)136 (3)
N1—H1N1···O4i0.97 (5)1.77 (5)2.711 (4)163 (3)
N2—H1N2···O4ii0.89 (4)2.02 (4)2.905 (4)179 (5)
N2—H2N2···O3i0.91 (4)1.92 (4)2.804 (5)165 (4)
C3—H3A···O1iii0.93 (4)2.58 (4)3.514 (6)176 (3)
Symmetry codes: (i) x, y1, z; (ii) x, y+1, z1/2; (iii) x+1, y+1, z.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

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.

References

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