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

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ISSN: 2056-9890

2-Amino-4-methyl­pyridinium 3-hy­dr­oxy­benzoate

aSchool of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: arazaki@usm.my

(Received 6 June 2013; accepted 12 June 2013; online 19 June 2013)

In the title salt, C6H9N2+·C7H5O3, the anion is essentially planar, with a dihedral angle of 2.72 (17)° between the benzene ring and the carboxyl­ate group. In the crystal, the anions are connected by O—H⋯O hydrogen bonds, forming a 41 helical chain along the c axis. 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. The ion pairs are further connected via another N—H⋯O hydrogen bond, resulting in a three-dimensional network.

Related literature

For the role of hydrogen bonding in crystal engineering, see: Goswami & Ghosh (1997[Goswami, S. & Ghosh, K. (1997). Tetrahedron Lett. 38, 4503-4506.]); Goswami et al. (1998[Goswami, S., Mahapatra, A. K., Nigam, G. D., Chinnakali, K. & Fun, H.-K. (1998). Acta Cryst. C54, 1301-1302.]); Lehn (1992[Lehn, J. M. (1992). J. Coord. Chem. 27, 3-6.]). For related structures, see: Kvick & Noordik (1977[Kvick, Å. & Noordik, J. (1977). Acta Cryst. B33, 2862-2866.]). 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+·C7H5O3

  • Mr = 246.26

  • Tetragonal, I 41 /a

  • a = 15.4435 (2) Å

  • c = 21.0395 (3) Å

  • V = 5017.96 (12) Å3

  • Z = 16

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.43 × 0.26 × 0.23 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.961, Tmax = 0.979

  • 46924 measured reflections

  • 3702 independent reflections

  • 3092 reflections with I > 2σ(I)

  • Rint = 0.058

Refinement
  • R[F2 > 2σ(F2)] = 0.060

  • wR(F2) = 0.130

  • S = 1.10

  • 3702 reflections

  • 180 parameters

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

  • Δρmax = 0.45 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O1⋯O2i 0.89 (2) 1.81 (2) 2.6970 (15) 172 (2)
N1—H1N1⋯O2ii 0.92 (2) 1.81 (2) 2.7221 (15) 172 (2)
N2—H1N2⋯O3ii 0.88 (2) 1.91 (2) 2.7852 (16) 170.6 (19)
N2—H2N2⋯O3 0.883 (19) 1.994 (19) 2.8454 (17) 161.7 (18)
Symmetry codes: (i) [-y+{\script{5\over 4}}, x-{\script{1\over 4}}, z-{\script{1\over 4}}]; (ii) [y+{\script{1\over 4}}, -x+{\script{7\over 4}}, -z+{\script{7\over 4}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. 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

Hydrogen bonding plays a key role in molecular recognition (Goswami & Ghosh, 1997) and crystal engineering research (Goswami et al., 1998). The design of highly specific solid-state compounds is of considerable significance in organic chemistry due to important applications of these compounds in the development of new optical, magnetic and electronic systems (Lehn, 1992). In order to study some hydrogen bonding interactions, the synthesis and structure of the title salt, (I), is presented here.

The asymmetric unit (Fig. 1) contains one 2-amino-4-methylpyridinium cation and one 3-hydroxybenzoate anion. A proton is transfered from the carboxyl group to atom N1 of 2-amino-4-methylpyridine, resulting in the widening of C1–N1–C5 angle of the pyridinium ring to 122.25 (12)°, compared to the corresponding angle of 117.3 (1)° in neutral 2-amino-4-methylpyridine (Kvick & Noordik, 1977). The 2-amino-4-methylpyridinium cation is essentially planar, with a maximum deviation of 0.007 (1) Å for atom C5. The carboxylate group of the 3-hydroxybenzoate anion is slightly twisted from the attached ring with a dihedral angle between the C7–C12 ring and the O2/O3/C13 plane being 2.72 (17)°. The bond lengths and angles are normal (Allen et al., 1987).

In the crystal packing (Fig. 2), the anions are connected by O1—H1O1···O2i hydrogen bonds (symmetry code in Table 1). The protonated N1 atom and the 2-amino group (N2) of the cation are hydrogen-bonded to the carboxylate oxygen atoms of the anion (O2 and O3, respectively) via a pair of intermolecular N1—H1N1···O2ii and N2—H1N2···O3ii hydrogen bonds (symmetry code in Table 1), forming an R22(8) (Bernstein et al., 1995) ring motif. These motifs are then connected via N2—H2N2···O3 hydrogen bond (Table 1), resulting in a three-dimensional network.

Related literature top

For the role of hydrogen bonding in crystal engineering, see: Goswami & Ghosh (1997); Goswami et al. (1998); Lehn (1992). For related structures, see: Kvick & Noordik (1977). 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

Hot methanol solution (20 ml) of 2-amino-4-methylpyridine (54 mg, Aldrich) and 3-hydroxybenzoic acid (35 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.

Refinement top

O- and N- bound H atoms were located in a difference Fourier map and allowed to be refined freely [O—H = 0.89 (2) Å and N—H = 0.88 (2) and 0.92 (2) Å]. The remaining H 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. One outlier (0 2 0) was omitted in the final refinement.

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 molecular structure of the title compound with atom labels with 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. The crystal packing of the title compound. The H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.
2-Amino-4-methylpyridinium 3-hydroxybenzoate top
Crystal data top
C6H9N2+·C7H5O3Dx = 1.304 Mg m3
Mr = 246.26Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I41/aCell parameters from 9925 reflections
Hall symbol: -I 4adθ = 2.6–30.0°
a = 15.4435 (2) ŵ = 0.09 mm1
c = 21.0395 (3) ÅT = 100 K
V = 5017.96 (12) Å3Block, colourless
Z = 160.43 × 0.26 × 0.23 mm
F(000) = 2080
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3702 independent reflections
Radiation source: fine-focus sealed tube3092 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.058
ϕ and ω scansθmax = 30.1°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 2121
Tmin = 0.961, Tmax = 0.979k = 2121
46924 measured reflectionsl = 2929
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)] = 0.060Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.10 w = 1/[σ2(Fo2) + (0.0518P)2 + 5.0006P]
where P = (Fo2 + 2Fc2)/3
3702 reflections(Δ/σ)max = 0.001
180 parametersΔρmax = 0.45 e Å3
0 restraintsΔρmin = 0.30 e Å3
Crystal data top
C6H9N2+·C7H5O3Z = 16
Mr = 246.26Mo Kα radiation
Tetragonal, I41/aµ = 0.09 mm1
a = 15.4435 (2) ÅT = 100 K
c = 21.0395 (3) Å0.43 × 0.26 × 0.23 mm
V = 5017.96 (12) Å3
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3702 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3092 reflections with I > 2σ(I)
Tmin = 0.961, Tmax = 0.979Rint = 0.058
46924 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0600 restraints
wR(F2) = 0.130H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.45 e Å3
3702 reflectionsΔρmin = 0.30 e Å3
180 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 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
N10.86599 (8)0.70451 (8)0.73009 (5)0.0194 (2)
N20.83258 (9)0.72622 (8)0.83600 (6)0.0248 (3)
C10.88264 (9)0.65309 (9)0.67916 (7)0.0225 (3)
H1A0.89540.67880.63920.027*
C20.88132 (10)0.56542 (9)0.68453 (7)0.0235 (3)
H2A0.89350.52990.64880.028*
C30.86144 (9)0.52768 (8)0.74423 (6)0.0196 (3)
C40.84480 (9)0.58047 (8)0.79506 (6)0.0196 (3)
H4A0.83120.55580.83520.024*
C50.84777 (9)0.67176 (9)0.78816 (6)0.0186 (3)
C60.86067 (10)0.43092 (9)0.75102 (7)0.0247 (3)
H6A0.83780.41530.79290.037*
H6B0.91980.40860.74670.037*
H6C0.82390.40560.71790.037*
O10.53366 (7)0.62983 (8)0.91513 (5)0.0265 (2)
O20.87586 (6)0.63112 (7)1.05329 (5)0.0220 (2)
O30.85543 (7)0.62684 (8)0.94864 (5)0.0278 (3)
C70.67779 (8)0.63135 (8)0.95960 (6)0.0174 (3)
H7A0.70300.62650.91860.021*
C80.58817 (9)0.63434 (9)0.96604 (6)0.0190 (3)
C90.55143 (9)0.64153 (10)1.02625 (7)0.0236 (3)
H9A0.49030.64361.03080.028*
C100.60424 (9)0.64573 (10)1.07952 (6)0.0234 (3)
H10A0.57890.65071.12050.028*
C110.69395 (9)0.64269 (9)1.07361 (6)0.0201 (3)
H11A0.72970.64551.11030.024*
C120.73072 (8)0.63549 (8)1.01339 (6)0.0163 (2)
C130.82751 (8)0.63125 (9)1.00454 (6)0.0182 (3)
H1O10.5651 (14)0.6250 (13)0.8797 (10)0.044 (6)*
H1N10.8684 (13)0.7633 (14)0.7223 (10)0.043 (6)*
H1N20.8428 (13)0.7814 (13)0.8286 (9)0.036 (5)*
H2N20.8309 (12)0.7032 (13)0.8744 (9)0.035 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0252 (6)0.0171 (5)0.0158 (6)0.0003 (4)0.0020 (4)0.0011 (4)
N20.0410 (7)0.0191 (6)0.0144 (6)0.0007 (5)0.0048 (5)0.0002 (5)
C10.0297 (7)0.0241 (7)0.0137 (6)0.0018 (5)0.0038 (5)0.0017 (5)
C20.0317 (7)0.0227 (7)0.0159 (7)0.0032 (5)0.0036 (5)0.0013 (5)
C30.0214 (6)0.0179 (6)0.0194 (7)0.0010 (5)0.0018 (5)0.0004 (5)
C40.0242 (6)0.0192 (6)0.0155 (6)0.0011 (5)0.0007 (5)0.0021 (5)
C50.0201 (6)0.0204 (6)0.0154 (6)0.0001 (5)0.0009 (5)0.0012 (5)
C60.0358 (8)0.0167 (6)0.0217 (7)0.0006 (5)0.0009 (6)0.0003 (5)
O10.0195 (5)0.0455 (7)0.0145 (5)0.0015 (4)0.0043 (4)0.0043 (4)
O20.0178 (4)0.0327 (5)0.0154 (5)0.0010 (4)0.0015 (4)0.0004 (4)
O30.0201 (5)0.0490 (7)0.0143 (5)0.0031 (4)0.0022 (4)0.0033 (4)
C70.0194 (6)0.0199 (6)0.0129 (6)0.0005 (5)0.0007 (5)0.0008 (5)
C80.0197 (6)0.0226 (6)0.0147 (6)0.0004 (5)0.0028 (5)0.0024 (5)
C90.0164 (6)0.0354 (8)0.0189 (7)0.0000 (5)0.0004 (5)0.0041 (6)
C100.0205 (6)0.0371 (8)0.0127 (6)0.0008 (5)0.0025 (5)0.0033 (5)
C110.0189 (6)0.0288 (7)0.0128 (6)0.0004 (5)0.0018 (5)0.0014 (5)
C120.0168 (6)0.0176 (6)0.0146 (6)0.0005 (4)0.0001 (4)0.0010 (4)
C130.0168 (6)0.0220 (6)0.0157 (6)0.0007 (5)0.0007 (5)0.0015 (5)
Geometric parameters (Å, º) top
N1—C51.3521 (17)C6—H6C0.9800
N1—C11.3582 (18)O1—C81.3641 (16)
N1—H1N10.92 (2)O1—H1O10.89 (2)
N2—C51.3326 (18)O2—C131.2686 (16)
N2—H1N20.88 (2)O3—C131.2546 (16)
N2—H2N20.88 (2)C7—C81.3914 (18)
C1—C21.359 (2)C7—C121.3975 (18)
C1—H1A0.9500C7—H7A0.9500
C2—C31.4184 (19)C8—C91.3924 (19)
C2—H2A0.9500C9—C101.3876 (19)
C3—C41.3691 (19)C9—H9A0.9500
C3—C61.5012 (19)C10—C111.3918 (19)
C4—C51.4180 (18)C10—H10A0.9500
C4—H4A0.9500C11—C121.3929 (18)
C6—H6A0.9800C11—H11A0.9500
C6—H6B0.9800C12—C131.5078 (18)
C5—N1—C1122.25 (12)H6A—C6—H6C109.5
C5—N1—H1N1122.5 (13)H6B—C6—H6C109.5
C1—N1—H1N1115.3 (14)C8—O1—H1O1108.9 (14)
C5—N2—H1N2116.4 (13)C8—C7—C12120.09 (12)
C5—N2—H2N2116.2 (13)C8—C7—H7A120.0
H1N2—N2—H2N2123.9 (18)C12—C7—H7A120.0
N1—C1—C2120.95 (13)O1—C8—C7122.39 (12)
N1—C1—H1A119.5O1—C8—C9117.83 (12)
C2—C1—H1A119.5C7—C8—C9119.77 (12)
C1—C2—C3119.10 (13)C10—C9—C8119.93 (13)
C1—C2—H2A120.5C10—C9—H9A120.0
C3—C2—H2A120.5C8—C9—H9A120.0
C4—C3—C2119.20 (12)C9—C10—C11120.76 (13)
C4—C3—C6121.12 (12)C9—C10—H10A119.6
C2—C3—C6119.67 (12)C11—C10—H10A119.6
C3—C4—C5120.39 (12)C10—C11—C12119.32 (12)
C3—C4—H4A119.8C10—C11—H11A120.3
C5—C4—H4A119.8C12—C11—H11A120.3
N2—C5—N1118.89 (12)C11—C12—C7120.12 (12)
N2—C5—C4122.99 (12)C11—C12—C13121.33 (12)
N1—C5—C4118.11 (12)C7—C12—C13118.55 (12)
C3—C6—H6A109.5O3—C13—O2123.75 (12)
C3—C6—H6B109.5O3—C13—C12117.31 (12)
H6A—C6—H6B109.5O2—C13—C12118.93 (12)
C3—C6—H6C109.5
C5—N1—C1—C20.2 (2)O1—C8—C9—C10179.56 (13)
N1—C1—C2—C30.6 (2)C7—C8—C9—C100.0 (2)
C1—C2—C3—C40.5 (2)C8—C9—C10—C110.1 (2)
C1—C2—C3—C6179.36 (14)C9—C10—C11—C120.1 (2)
C2—C3—C4—C50.3 (2)C10—C11—C12—C70.0 (2)
C6—C3—C4—C5178.53 (13)C10—C11—C12—C13179.53 (13)
C1—N1—C5—N2179.63 (13)C8—C7—C12—C110.0 (2)
C1—N1—C5—C41.0 (2)C8—C7—C12—C13179.47 (12)
C3—C4—C5—N2179.66 (14)C11—C12—C13—O3178.37 (13)
C3—C4—C5—N11.0 (2)C7—C12—C13—O32.12 (19)
C12—C7—C8—O1179.46 (12)C11—C12—C13—O22.58 (19)
C12—C7—C8—C90.0 (2)C7—C12—C13—O2176.92 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O1···O2i0.89 (2)1.81 (2)2.6970 (15)172 (2)
N1—H1N1···O2ii0.92 (2)1.81 (2)2.7221 (15)172 (2)
N2—H1N2···O3ii0.88 (2)1.91 (2)2.7852 (16)170.6 (19)
N2—H2N2···O30.883 (19)1.994 (19)2.8454 (17)161.7 (18)
Symmetry codes: (i) y+5/4, x1/4, z1/4; (ii) y+1/4, x+7/4, z+7/4.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C7H5O3
Mr246.26
Crystal system, space groupTetragonal, I41/a
Temperature (K)100
a, c (Å)15.4435 (2), 21.0395 (3)
V3)5017.96 (12)
Z16
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.43 × 0.26 × 0.23
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.961, 0.979
No. of measured, independent and
observed [I > 2σ(I)] reflections
46924, 3702, 3092
Rint0.058
(sin θ/λ)max1)0.706
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.060, 0.130, 1.10
No. of reflections3702
No. of parameters180
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.45, 0.30

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
O1—H1O1···O2i0.89 (2)1.81 (2)2.6970 (15)172 (2)
N1—H1N1···O2ii0.92 (2)1.81 (2)2.7221 (15)172 (2)
N2—H1N2···O3ii0.88 (2)1.91 (2)2.7852 (16)170.6 (19)
N2—H2N2···O30.883 (19)1.994 (19)2.8454 (17)161.7 (18)
Symmetry codes: (i) y+5/4, x1/4, z1/4; (ii) y+1/4, x+7/4, z+7/4.
 

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 the TWAS–USM fellowship.

References

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