organic compounds
2-Amino-5-methylpyridinium 4-methylbenzoate
aSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bDepartment of Physics, Faculty of Science, University of Mazandaran, Babolsar, Iran
*Correspondence e-mail: arazaki@usm.my
The 4-methylbenzoate anion of the title salt, C6H9N2+·C8H7O2−, is nearly planar, with a dihedral angle of 6.26 (10)° between the benzene ring and the carboxylate group. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxylate O atoms of the anion via a pair of N—H⋯O hydrogen bonds with an R22(8) ring motif, forming an approximately planar with a dihedral angle of 9.63 (4)° between the pyridinium and benzene rings. The ion pairs are further connected via N—H⋯O and weak C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane.
Related literature
For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996). For related structures, see: Nahringbauer & Kvick (1977); Thanigaimani et al. (2012a,b,c). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2009); cell SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009).
Supporting information
https://doi.org/10.1107/S1600536812050374/is5229sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812050374/is5229Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536812050374/is5229Isup3.cml
Hot methanol solutions (20 ml) of 2-amino5-methylpyridine (54 mg, Aldrich) and 4-methylbenzoic acid (34 mg, Merck) were mixed and warmed over a heating magnetic stirrer hotplate for a few minutes. The resulting solution was allowed to cool slowly at room temperature and crystals of the title compound (I) appeared after a few days.
N-bound H Atoms were located in a difference Fourier maps and refined freely [refined N—H distances 0.976 (18), 0.920 (16) and 0.926 (16) Å]. The remaining hydrogen atoms were positioned geometrically (C—H = 0.95 or 0.98 Å) and were refined using a riding model, with Uiso(H) = 1.2Ueq(C) or 1.5Ueq(methyl C). A rotating group model was used for the methyl group.
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-bond interactions. Related crystal structures of 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977), 2-amino-5-methylpyridinium 6-oxo-1,6-dihydropyridine-2-carboxylate (Thanigaimani et al., 2012a), 2-amino-5-methylpyridinium 3-chlorobenzoate (Thanigaimani et al., 2012b) and 2-amino-5-methylpyridinium 2-aminobenzoate (Thanigaimani et al., 2012c) have been reported. In order to study potential hydrogen bonding interactions, the
determination of the title compound (I) was carried out.The
(Fig. 1) contains one 2-amino-5-methylpyridinium cation and one 4-methylbenzoate anion. In the 2-amino-5-methylpyridinium cation, a wider than normal angle [C9—N1—C13 = 122.15 (8)°] is subtended at the protonated N1 atom. The 2-amino-5-methylpyridinium cation is planar with a maximum deviation of 0.005 (1) Å for atom C9. The dihedral angle between the pyridine (N1/C9–C13) and benzene (C1–C6) rings is 9.63 (4)°. The bond lengths (Allen et al., 1987) and angles are normal. In the crystal packing (Fig. 2), the protonated N1 atom and a nitrogen atom of the 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of intermolecular N1—H1N1···O1i and N2—H1N2···O2i hydrogen bonds (symmetry code in Table 1), forming a ring motif R22(8) (Bernstein et al., 1995). Furthermore, these motifs are connected via N2—H2N2···O1ii and C10—H10A···O2iii hydrogen bonds (symmetry codes in Table 1), to form a two-dimensional network parallel to the bc plane.For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996). For related structures, see: Nahringbauer & Kvick (1977); Thanigaimani et al. (2012a,b,c). For hydrogen-bond motifs, see: Bernstein et al. (1995). For bond-length data, see: Allen et al. (1987). For stability of the temperature controller used for the data collection, see: Cosier & Glazer (1986).
Data collection: APEX2 (Bruker, 2009); cell
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).C6H9N2+·C8H7O2− | F(000) = 520 |
Mr = 244.29 | Dx = 1.315 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 6272 reflections |
a = 9.6315 (5) Å | θ = 2.6–32.6° |
b = 10.8713 (6) Å | µ = 0.09 mm−1 |
c = 12.1481 (7) Å | T = 100 K |
β = 104.093 (1)° | Block, colourless |
V = 1233.71 (12) Å3 | 0.52 × 0.32 × 0.15 mm |
Z = 4 |
Bruker SMART APEXII CCD area-detector diffractometer | 4493 independent reflections |
Radiation source: fine-focus sealed tube | 3783 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.027 |
φ and ω scans | θmax = 32.7°, θmin = 2.6° |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | h = −14→14 |
Tmin = 0.955, Tmax = 0.987 | k = −16→16 |
18139 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.125 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0678P)2 + 0.3153P] where P = (Fo2 + 2Fc2)/3 |
4493 reflections | (Δ/σ)max = 0.001 |
177 parameters | Δρmax = 0.43 e Å−3 |
0 restraints | Δρmin = −0.29 e Å−3 |
C6H9N2+·C8H7O2− | V = 1233.71 (12) Å3 |
Mr = 244.29 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.6315 (5) Å | µ = 0.09 mm−1 |
b = 10.8713 (6) Å | T = 100 K |
c = 12.1481 (7) Å | 0.52 × 0.32 × 0.15 mm |
β = 104.093 (1)° |
Bruker SMART APEXII CCD area-detector diffractometer | 4493 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2009) | 3783 reflections with I > 2σ(I) |
Tmin = 0.955, Tmax = 0.987 | Rint = 0.027 |
18139 measured reflections |
R[F2 > 2σ(F2)] = 0.043 | 0 restraints |
wR(F2) = 0.125 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.43 e Å−3 |
4493 reflections | Δρmin = −0.29 e Å−3 |
177 parameters |
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 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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.07967 (7) | 1.13827 (6) | 0.07082 (5) | 0.01774 (14) | |
O2 | 0.20480 (8) | 1.12140 (6) | −0.06122 (6) | 0.01914 (15) | |
C1 | 0.23323 (9) | 0.93283 (8) | 0.19086 (7) | 0.01486 (16) | |
H1A | 0.1613 | 0.9680 | 0.2224 | 0.018* | |
C2 | 0.31890 (10) | 0.83760 (8) | 0.24780 (7) | 0.01618 (16) | |
H2A | 0.3048 | 0.8090 | 0.3182 | 0.019* | |
C3 | 0.42490 (9) | 0.78366 (8) | 0.20317 (7) | 0.01589 (16) | |
C4 | 0.44248 (10) | 0.82614 (9) | 0.09878 (8) | 0.01896 (18) | |
H4A | 0.5132 | 0.7900 | 0.0665 | 0.023* | |
C5 | 0.35734 (10) | 0.92094 (9) | 0.04167 (7) | 0.01693 (17) | |
H5A | 0.3702 | 0.9484 | −0.0294 | 0.020* | |
C6 | 0.25310 (9) | 0.97626 (8) | 0.08768 (7) | 0.01277 (15) | |
C7 | 0.17236 (9) | 1.08592 (8) | 0.02773 (7) | 0.01374 (15) | |
C8 | 0.51917 (10) | 0.68238 (9) | 0.26587 (8) | 0.02109 (19) | |
H8A | 0.5215 | 0.6869 | 0.3469 | 0.032* | |
H8B | 0.6164 | 0.6921 | 0.2556 | 0.032* | |
H8C | 0.4808 | 0.6024 | 0.2358 | 0.032* | |
N1 | 0.94348 (8) | 0.32387 (7) | 0.93651 (6) | 0.01462 (15) | |
N2 | 1.04273 (9) | 0.28128 (8) | 0.78450 (7) | 0.01928 (16) | |
C9 | 0.95687 (9) | 0.35009 (8) | 0.83058 (7) | 0.01471 (16) | |
C10 | 0.87654 (10) | 0.45002 (9) | 0.77234 (7) | 0.01714 (17) | |
H10A | 0.8825 | 0.4703 | 0.6976 | 0.021* | |
C11 | 0.79056 (10) | 0.51697 (8) | 0.82424 (8) | 0.01771 (17) | |
H11A | 0.7373 | 0.5839 | 0.7847 | 0.021* | |
C12 | 0.77883 (9) | 0.48901 (8) | 0.93576 (8) | 0.01643 (16) | |
C13 | 0.85738 (9) | 0.39091 (8) | 0.98802 (7) | 0.01558 (16) | |
H13A | 0.8517 | 0.3689 | 1.0625 | 0.019* | |
C14 | 0.68490 (11) | 0.56433 (9) | 0.99240 (9) | 0.02191 (19) | |
H14A | 0.6859 | 0.5287 | 1.0667 | 0.033* | |
H14B | 0.5867 | 0.5644 | 0.9450 | 0.033* | |
H14C | 0.7209 | 0.6489 | 1.0024 | 0.033* | |
H1N2 | 1.0977 (16) | 0.2237 (15) | 0.8310 (13) | 0.035 (4)* | |
H2N2 | 1.0599 (17) | 0.3085 (15) | 0.7168 (14) | 0.035 (4)* | |
H1N1 | 0.9942 (18) | 0.2547 (17) | 0.9795 (15) | 0.046 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0208 (3) | 0.0182 (3) | 0.0149 (3) | 0.0068 (2) | 0.0055 (2) | 0.0002 (2) |
O2 | 0.0245 (3) | 0.0186 (3) | 0.0158 (3) | 0.0042 (2) | 0.0075 (2) | 0.0036 (2) |
C1 | 0.0150 (4) | 0.0143 (4) | 0.0157 (4) | 0.0013 (3) | 0.0046 (3) | 0.0008 (3) |
C2 | 0.0175 (4) | 0.0155 (4) | 0.0156 (4) | 0.0011 (3) | 0.0041 (3) | 0.0021 (3) |
C3 | 0.0149 (4) | 0.0135 (4) | 0.0182 (4) | 0.0011 (3) | 0.0021 (3) | 0.0004 (3) |
C4 | 0.0179 (4) | 0.0184 (4) | 0.0221 (4) | 0.0052 (3) | 0.0076 (3) | 0.0013 (3) |
C5 | 0.0184 (4) | 0.0174 (4) | 0.0162 (4) | 0.0030 (3) | 0.0064 (3) | 0.0015 (3) |
C6 | 0.0129 (3) | 0.0119 (3) | 0.0131 (3) | 0.0002 (3) | 0.0023 (3) | −0.0007 (3) |
C7 | 0.0157 (4) | 0.0127 (3) | 0.0122 (3) | 0.0002 (3) | 0.0021 (3) | −0.0012 (3) |
C8 | 0.0197 (4) | 0.0171 (4) | 0.0249 (4) | 0.0044 (3) | 0.0024 (3) | 0.0035 (3) |
N1 | 0.0161 (3) | 0.0144 (3) | 0.0134 (3) | 0.0003 (2) | 0.0037 (2) | 0.0022 (2) |
N2 | 0.0229 (4) | 0.0206 (4) | 0.0159 (3) | 0.0040 (3) | 0.0076 (3) | 0.0036 (3) |
C9 | 0.0158 (4) | 0.0146 (4) | 0.0135 (3) | −0.0019 (3) | 0.0032 (3) | 0.0012 (3) |
C10 | 0.0187 (4) | 0.0170 (4) | 0.0151 (4) | 0.0001 (3) | 0.0028 (3) | 0.0044 (3) |
C11 | 0.0172 (4) | 0.0149 (4) | 0.0203 (4) | 0.0003 (3) | 0.0032 (3) | 0.0036 (3) |
C12 | 0.0149 (4) | 0.0144 (4) | 0.0198 (4) | −0.0014 (3) | 0.0041 (3) | 0.0001 (3) |
C13 | 0.0165 (4) | 0.0160 (4) | 0.0146 (4) | −0.0012 (3) | 0.0043 (3) | 0.0003 (3) |
C14 | 0.0203 (4) | 0.0207 (4) | 0.0259 (4) | 0.0030 (3) | 0.0077 (3) | −0.0002 (3) |
O1—C7 | 1.2737 (10) | N1—C9 | 1.3545 (11) |
O2—C7 | 1.2564 (11) | N1—C13 | 1.3649 (11) |
C1—C6 | 1.3956 (12) | N1—H1N1 | 0.976 (18) |
C1—C2 | 1.3975 (12) | N2—C9 | 1.3351 (12) |
C1—H1A | 0.9500 | N2—H1N2 | 0.920 (16) |
C2—C3 | 1.3962 (13) | N2—H2N2 | 0.926 (16) |
C2—H2A | 0.9500 | C9—C10 | 1.4187 (12) |
C3—C4 | 1.3981 (13) | C10—C11 | 1.3665 (13) |
C3—C8 | 1.5100 (12) | C10—H10A | 0.9500 |
C4—C5 | 1.3924 (12) | C11—C12 | 1.4195 (13) |
C4—H4A | 0.9500 | C11—H11A | 0.9500 |
C5—C6 | 1.3984 (12) | C12—C13 | 1.3708 (12) |
C5—H5A | 0.9500 | C12—C14 | 1.5052 (13) |
C6—C7 | 1.5101 (12) | C13—H13A | 0.9500 |
C8—H8A | 0.9800 | C14—H14A | 0.9800 |
C8—H8B | 0.9800 | C14—H14B | 0.9800 |
C8—H8C | 0.9800 | C14—H14C | 0.9800 |
C6—C1—C2 | 120.10 (8) | C9—N1—C13 | 122.15 (8) |
C6—C1—H1A | 120.0 | C9—N1—H1N1 | 121.3 (10) |
C2—C1—H1A | 120.0 | C13—N1—H1N1 | 116.6 (10) |
C3—C2—C1 | 121.23 (8) | C9—N2—H1N2 | 116.5 (10) |
C3—C2—H2A | 119.4 | C9—N2—H2N2 | 117.1 (10) |
C1—C2—H2A | 119.4 | H1N2—N2—H2N2 | 124.3 (14) |
C2—C3—C4 | 118.36 (8) | N2—C9—N1 | 119.50 (8) |
C2—C3—C8 | 121.14 (8) | N2—C9—C10 | 122.56 (8) |
C4—C3—C8 | 120.51 (8) | N1—C9—C10 | 117.94 (8) |
C5—C4—C3 | 120.64 (8) | C11—C10—C9 | 119.73 (8) |
C5—C4—H4A | 119.7 | C11—C10—H10A | 120.1 |
C3—C4—H4A | 119.7 | C9—C10—H10A | 120.1 |
C4—C5—C6 | 120.81 (8) | C10—C11—C12 | 121.62 (8) |
C4—C5—H5A | 119.6 | C10—C11—H11A | 119.2 |
C6—C5—H5A | 119.6 | C12—C11—H11A | 119.2 |
C1—C6—C5 | 118.84 (8) | C13—C12—C11 | 116.45 (8) |
C1—C6—C7 | 122.21 (7) | C13—C12—C14 | 122.48 (8) |
C5—C6—C7 | 118.84 (7) | C11—C12—C14 | 121.08 (8) |
O2—C7—O1 | 124.21 (8) | N1—C13—C12 | 122.11 (8) |
O2—C7—C6 | 116.77 (8) | N1—C13—H13A | 118.9 |
O1—C7—C6 | 118.99 (7) | C12—C13—H13A | 118.9 |
C3—C8—H8A | 109.5 | C12—C14—H14A | 109.5 |
C3—C8—H8B | 109.5 | C12—C14—H14B | 109.5 |
H8A—C8—H8B | 109.5 | H14A—C14—H14B | 109.5 |
C3—C8—H8C | 109.5 | C12—C14—H14C | 109.5 |
H8A—C8—H8C | 109.5 | H14A—C14—H14C | 109.5 |
H8B—C8—H8C | 109.5 | H14B—C14—H14C | 109.5 |
C6—C1—C2—C3 | −0.32 (13) | C1—C6—C7—O1 | −2.27 (12) |
C1—C2—C3—C4 | −0.82 (13) | C5—C6—C7—O1 | −178.40 (8) |
C1—C2—C3—C8 | 178.86 (8) | C13—N1—C9—N2 | 179.99 (8) |
C2—C3—C4—C5 | 0.77 (14) | C13—N1—C9—C10 | −0.73 (13) |
C8—C3—C4—C5 | −178.91 (9) | N2—C9—C10—C11 | −179.98 (9) |
C3—C4—C5—C6 | 0.41 (14) | N1—C9—C10—C11 | 0.77 (13) |
C2—C1—C6—C5 | 1.49 (13) | C9—C10—C11—C12 | −0.17 (14) |
C2—C1—C6—C7 | −174.64 (8) | C10—C11—C12—C13 | −0.48 (13) |
C4—C5—C6—C1 | −1.54 (13) | C10—C11—C12—C14 | 179.36 (9) |
C4—C5—C6—C7 | 174.72 (8) | C9—N1—C13—C12 | 0.07 (13) |
C1—C6—C7—O2 | 175.94 (8) | C11—C12—C13—N1 | 0.54 (13) |
C5—C6—C7—O2 | −0.19 (12) | C14—C12—C13—N1 | −179.30 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H1N2···O2i | 0.920 (16) | 1.832 (16) | 2.7469 (11) | 172.7 (15) |
N2—H2N2···O1ii | 0.926 (16) | 1.919 (17) | 2.8424 (11) | 175.4 (15) |
N1—H1N1···O1i | 0.976 (18) | 1.751 (18) | 2.7224 (10) | 173.1 (16) |
C10—H10A···O2iii | 0.95 | 2.34 | 3.1120 (11) | 138 |
Symmetry codes: (i) x+1, y−1, z+1; (ii) x+1, −y+3/2, z+1/2; (iii) −x+1, y−1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C6H9N2+·C8H7O2− |
Mr | 244.29 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 100 |
a, b, c (Å) | 9.6315 (5), 10.8713 (6), 12.1481 (7) |
β (°) | 104.093 (1) |
V (Å3) | 1233.71 (12) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.52 × 0.32 × 0.15 |
Data collection | |
Diffractometer | Bruker SMART APEXII CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2009) |
Tmin, Tmax | 0.955, 0.987 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 18139, 4493, 3783 |
Rint | 0.027 |
(sin θ/λ)max (Å−1) | 0.759 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.043, 0.125, 1.03 |
No. of reflections | 4493 |
No. of parameters | 177 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.43, −0.29 |
Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H1N2···O2i | 0.920 (16) | 1.832 (16) | 2.7469 (11) | 172.7 (15) |
N2—H2N2···O1ii | 0.926 (16) | 1.919 (17) | 2.8424 (11) | 175.4 (15) |
N1—H1N1···O1i | 0.976 (18) | 1.751 (18) | 2.7224 (10) | 173.1 (16) |
C10—H10A···O2iii | 0.95 | 2.34 | 3.1120 (11) | 138 |
Symmetry codes: (i) x+1, y−1, z+1; (ii) x+1, −y+3/2, z+1/2; (iii) −x+1, y−1/2, −z+1/2. |
Footnotes
‡Thomson Reuters ResearcherID: A-5599-2009.
Acknowledgements
The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the research facilities and USM Short Term Grant No. 304/PFIZIK/6312078 to conduct this work. KT thanks The Academy of Sciences for the Developing World and USM for a TWAS–USM fellowship.
References
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. CSD CrossRef Web of Science Google Scholar
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107. CrossRef CAS Web of Science IUCr Journals Google Scholar
Katritzky, A. R., Rees, C. W. & Scriven, E. F. V. (1996). In Comprehensive Heterocyclic Chemistry II. Oxford: Pergamon Press. Google Scholar
Nahringbauer, I. & Kvick, Å. (1977). Acta Cryst. B33, 2902–2905. CSD CrossRef CAS IUCr Journals Web of Science Google Scholar
Pozharski, A. F., Soldatenkov, A. T. & Katritzky, A. R. (1997). In Heterocycles in Life and Society. New York: Wiley. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012a). Acta Cryst. E68, o3151–o3152. CSD CrossRef IUCr Journals Google Scholar
Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012b). Acta Cryst. E68, o3195. CSD CrossRef IUCr Journals Google Scholar
Thanigaimani, K., Farhadikoutenaei, A., Khalib, N. C., Arshad, S. & Razak, I. A. (2012c). Acta Cryst. E68, o3196–o3197. CSD CrossRef IUCr Journals Google Scholar
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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-bond interactions. Related crystal structures of 2-amino-5-methylpyridine (Nahringbauer & Kvick, 1977), 2-amino-5-methylpyridinium 6-oxo-1,6-dihydropyridine-2-carboxylate (Thanigaimani et al., 2012a), 2-amino-5-methylpyridinium 3-chlorobenzoate (Thanigaimani et al., 2012b) and 2-amino-5-methylpyridinium 2-aminobenzoate (Thanigaimani et al., 2012c) have been reported. In order to study potential hydrogen bonding interactions, the crystal structure determination of the title compound (I) was carried out.
The asymmetric unit (Fig. 1) contains one 2-amino-5-methylpyridinium cation and one 4-methylbenzoate anion. In the 2-amino-5-methylpyridinium cation, a wider than normal angle [C9—N1—C13 = 122.15 (8)°] is subtended at the protonated N1 atom. The 2-amino-5-methylpyridinium cation is planar with a maximum deviation of 0.005 (1) Å for atom C9. The dihedral angle between the pyridine (N1/C9–C13) and benzene (C1–C6) rings is 9.63 (4)°. The bond lengths (Allen et al., 1987) and angles are normal. In the crystal packing (Fig. 2), the protonated N1 atom and a nitrogen atom of the 2-amino group (N2) are hydrogen-bonded to the carboxylate oxygen atoms (O1 and O2) via a pair of intermolecular N1—H1N1···O1i and N2—H1N2···O2i hydrogen bonds (symmetry code in Table 1), forming a ring motif R22(8) (Bernstein et al., 1995). Furthermore, these motifs are connected via N2—H2N2···O1ii and C10—H10A···O2iii hydrogen bonds (symmetry codes in Table 1), to form a two-dimensional network parallel to the bc plane.