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

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ISSN: 2056-9890

2-Amino-5-methyl­pyridinium 3-chloro­benzoate

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

(Received 1 October 2012; accepted 17 October 2012; online 24 October 2012)

The 3-chloro­benzoate anion of the title salt, C6H9N2+·C7H4ClO2, is nearly planar with a dihedral angle of 2.44 (13)° 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 ion pair with a dihedral angle of 7.92 (5)° between the pyridinium and benzene rings. The ion pairs are further connected via N—H⋯O and 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[Pozharski, A. F., Soldatenkov, A. T. & Katritzky, A. R. (1997). In Heterocycles in Life and Society. New York: Wiley.]); Katritzky et al. (1996[Katritzky, A. R., Rees, C. W. & Scriven, E. F. V. (1996). In Comprehensive Heterocyclic Chemistry II. Oxford: Pergamon Press.]). For details of hydrogen bonding, see: Jeffrey (1997[Jeffrey, G. A. (1997). In An Introduction of Hydrogen Bonding. Oxford University Press.]); Scheiner (1997[Scheiner, S. (1997). In 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 stability of the temperature controller used for 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+·C7H4ClO2

  • Mr = 264.70

  • Monoclinic, P 21 /c

  • a = 9.0318 (11) Å

  • b = 11.6590 (14) Å

  • c = 12.1166 (15) Å

  • β = 101.521 (2)°

  • V = 1250.2 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.30 mm−1

  • T = 100 K

  • 0.53 × 0.31 × 0.22 mm

Data collection
  • Bruker SMART APEXII DUO CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.856, Tmax = 0.936

  • 13594 measured reflections

  • 3629 independent reflections

  • 3201 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.115

  • S = 1.06

  • 3629 reflections

  • 176 parameters

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

  • Δρmax = 0.48 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N1⋯O1 1.00 (2) 1.68 (2) 2.6716 (13) 174 (2)
N2—H1N2⋯O2 0.946 (19) 1.820 (19) 2.7618 (15) 173.0 (19)
N2—H2N2⋯O1i 0.90 (2) 1.95 (2) 2.8526 (14) 174.0 (17)
C2—H2A⋯O2ii 0.95 2.52 3.2104 (15) 130
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z+{\script{1\over 2}}]; (ii) [-x+1, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

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

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 (Jeffrey, 1997; Scheiner, 1997). In order to study some interesting hydrogen bonding interactions, the synthesis and structure of the title compound, (I), is presented here.

The asymmetric unit of the title compound contains a protonated 2-amino-5-methylpyridinium cation and a 3-chlorobenzoate anion (Fig. 1). In the 2-amino-5-methylpyridinium cation, a wider than normal angle [C1—N1—C5 = 122.50 (10)°] is subtended at the protonated N1 atom. The 2-amino-5-methylpyridinium cation is planar with a maximum deviation of 0.001 (1) Å for atom C2. The dihedral angle between the pyridine (N1/C1–C5) and benzene (C8–C13) rings is 7.92 (5)°. 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 N—H···O hydrogen bonds (Table 1), forming a ring motif R22(8) (Bernstein et al., 1995). Furthermore, these motifs are connected via N2—H2N2···O1i and C2—H2A···O2ii hydrogen bonds to form a two-dimensional network parallel to the bc plane.

Related literature top

For background to the chemistry of substituted pyridines, see: Pozharski et al. (1997); Katritzky et al. (1996). For details of hydrogen bonding, see: Jeffrey (1997); Scheiner (1997). 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 top

Hot methanol solutions (20 ml) of 2-amino5-methylpyridine (54 mg, Aldrich) and 3-chlorobenzoic acid (39 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

N-bound H atoms were located in a difference Fourier maps and refined freely [refined N—H distances 1.00 (2), 0.949 (19) and 0.90 (2) Å]. The remaining H atoms were positioned geometrically (C—H= 0.95 and 0.98 Å) and were refined using a riding model, with Uiso(H) = 1.2 Ueq(C) or 1.5Ueq(methyl C). A rotating-group model was used for the methyl group. In the final refinement, four outliers were omitted (1 1 8, 1 0 8, 2 3 1 and -1 4 8).

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, showing hydrogen-bonded (dashed lines) two-dimensional networks parallel to the bc plane.
2-Amino-5-methylpyridinium 3-chlorobenzoate top
Crystal data top
C6H9N2+·C7H4ClO2F(000) = 552
Mr = 264.70Dx = 1.406 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6768 reflections
a = 9.0318 (11) Åθ = 2.3–30.1°
b = 11.6590 (14) ŵ = 0.30 mm1
c = 12.1166 (15) ÅT = 100 K
β = 101.521 (2)°Block, colourless
V = 1250.2 (3) Å30.53 × 0.31 × 0.22 mm
Z = 4
Data collection top
Bruker SMART APEXII DUO CCD area-detector
diffractometer
3629 independent reflections
Radiation source: fine-focus sealed tube3201 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
ϕ and ω scansθmax = 30.1°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1212
Tmin = 0.856, Tmax = 0.936k = 1616
13594 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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.070P)2 + 0.2814P]
where P = (Fo2 + 2Fc2)/3
3629 reflections(Δ/σ)max < 0.001
176 parametersΔρmax = 0.48 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C6H9N2+·C7H4ClO2V = 1250.2 (3) Å3
Mr = 264.70Z = 4
Monoclinic, P21/cMo Kα radiation
a = 9.0318 (11) ŵ = 0.30 mm1
b = 11.6590 (14) ÅT = 100 K
c = 12.1166 (15) Å0.53 × 0.31 × 0.22 mm
β = 101.521 (2)°
Data collection top
Bruker SMART APEXII DUO CCD area-detector
diffractometer
3629 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3201 reflections with I > 2σ(I)
Tmin = 0.856, Tmax = 0.936Rint = 0.031
13594 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.115H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.48 e Å3
3629 reflectionsΔρmin = 0.33 e Å3
176 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
Cl11.05016 (3)0.25195 (2)0.66489 (3)0.02535 (11)
O10.60056 (10)0.65207 (8)0.46906 (7)0.02385 (19)
O20.72588 (10)0.62484 (8)0.64581 (7)0.02350 (19)
N10.45310 (10)0.81988 (8)0.55172 (8)0.01776 (19)
N20.55220 (12)0.77783 (10)0.73908 (9)0.0219 (2)
C10.46396 (12)0.84318 (9)0.66248 (10)0.0179 (2)
C20.37858 (13)0.93693 (10)0.69173 (10)0.0210 (2)
H2A0.38330.95610.76860.025*
C30.28968 (13)0.99913 (10)0.60827 (11)0.0218 (2)
H3A0.23271.06150.62830.026*
C40.27996 (12)0.97334 (10)0.49275 (10)0.0204 (2)
C50.36421 (12)0.88246 (10)0.46891 (10)0.0190 (2)
H5A0.36070.86240.39240.023*
C60.18156 (14)1.04262 (11)0.40224 (11)0.0262 (3)
H6A0.19681.01700.32830.039*
H6B0.20841.12390.41240.039*
H6C0.07541.03210.40700.039*
C70.69320 (12)0.59788 (9)0.54401 (9)0.0175 (2)
C80.76799 (11)0.49160 (9)0.50805 (9)0.0159 (2)
C90.86515 (12)0.42923 (9)0.59063 (9)0.0172 (2)
H9A0.88400.45370.66700.021*
C100.93380 (12)0.33117 (9)0.55982 (10)0.0180 (2)
C110.91118 (13)0.29472 (10)0.44867 (10)0.0212 (2)
H11A0.96030.22800.42880.025*
C120.81496 (13)0.35797 (10)0.36693 (10)0.0224 (2)
H12A0.79870.33450.29040.027*
C130.74215 (12)0.45553 (10)0.39638 (9)0.0198 (2)
H13A0.67500.49730.34020.024*
H1N10.511 (3)0.7554 (18)0.526 (2)0.055 (7)*
H1N20.617 (2)0.7251 (16)0.7129 (17)0.037 (5)*
H2N20.574 (2)0.8015 (16)0.8114 (16)0.035 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02441 (17)0.02607 (17)0.02424 (17)0.00991 (9)0.00168 (12)0.00262 (10)
O10.0302 (4)0.0259 (4)0.0161 (4)0.0125 (3)0.0061 (3)0.0030 (3)
O20.0285 (4)0.0253 (4)0.0163 (4)0.0075 (3)0.0034 (3)0.0021 (3)
N10.0183 (4)0.0195 (4)0.0156 (4)0.0034 (3)0.0037 (3)0.0019 (3)
N20.0240 (5)0.0262 (5)0.0150 (5)0.0050 (4)0.0025 (4)0.0025 (4)
C10.0168 (5)0.0201 (5)0.0173 (5)0.0003 (4)0.0047 (4)0.0028 (4)
C20.0206 (5)0.0231 (5)0.0203 (5)0.0005 (4)0.0066 (4)0.0061 (4)
C30.0193 (5)0.0207 (5)0.0263 (6)0.0030 (4)0.0064 (4)0.0047 (4)
C40.0183 (5)0.0202 (5)0.0230 (5)0.0024 (4)0.0045 (4)0.0000 (4)
C50.0189 (5)0.0215 (5)0.0166 (5)0.0021 (4)0.0038 (4)0.0006 (4)
C60.0253 (6)0.0258 (6)0.0269 (6)0.0084 (4)0.0038 (5)0.0024 (5)
C70.0195 (5)0.0181 (5)0.0163 (5)0.0023 (4)0.0069 (4)0.0013 (4)
C80.0156 (4)0.0169 (4)0.0159 (5)0.0012 (3)0.0049 (4)0.0000 (4)
C90.0166 (4)0.0187 (5)0.0164 (5)0.0011 (4)0.0037 (4)0.0000 (4)
C100.0146 (4)0.0188 (5)0.0205 (5)0.0019 (3)0.0030 (4)0.0016 (4)
C110.0197 (5)0.0203 (5)0.0238 (6)0.0029 (4)0.0046 (4)0.0039 (4)
C120.0242 (5)0.0246 (5)0.0182 (5)0.0032 (4)0.0036 (4)0.0047 (4)
C130.0208 (5)0.0223 (5)0.0160 (5)0.0033 (4)0.0029 (4)0.0003 (4)
Geometric parameters (Å, º) top
Cl1—C101.7447 (11)C5—H5A0.9500
O1—C71.2729 (13)C6—H6A0.9800
O2—C71.2498 (14)C6—H6B0.9800
N1—C11.3535 (14)C6—H6C0.9800
N1—C51.3645 (14)C7—C81.5163 (15)
N1—H1N11.00 (2)C8—C131.3914 (15)
N2—C11.3348 (15)C8—C91.3961 (15)
N2—H1N20.949 (19)C9—C101.3870 (15)
N2—H2N20.90 (2)C9—H9A0.9500
C1—C21.4227 (15)C10—C111.3878 (16)
C2—C31.3671 (17)C11—C121.3914 (16)
C2—H2A0.9500C11—H11A0.9500
C3—C41.4171 (17)C12—C131.3955 (16)
C3—H3A0.9500C12—H12A0.9500
C4—C51.3686 (15)C13—H13A0.9500
C4—C61.5019 (16)
C1—N1—C5122.50 (10)C4—C6—H6C109.5
C1—N1—H1N1121.5 (14)H6A—C6—H6C109.5
C5—N1—H1N1116.0 (14)H6B—C6—H6C109.5
C1—N2—H1N2117.5 (12)O2—C7—O1124.84 (10)
C1—N2—H2N2119.1 (12)O2—C7—C8117.27 (9)
H1N2—N2—H2N2119.4 (17)O1—C7—C8117.88 (10)
N2—C1—N1119.33 (10)C13—C8—C9119.93 (10)
N2—C1—C2122.91 (11)C13—C8—C7121.91 (9)
N1—C1—C2117.75 (10)C9—C8—C7118.16 (9)
C3—C2—C1119.39 (11)C10—C9—C8119.15 (10)
C3—C2—H2A120.3C10—C9—H9A120.4
C1—C2—H2A120.3C8—C9—H9A120.4
C2—C3—C4121.97 (10)C9—C10—C11121.77 (10)
C2—C3—H3A119.0C9—C10—Cl1118.45 (9)
C4—C3—H3A119.0C11—C10—Cl1119.77 (8)
C5—C4—C3116.45 (10)C10—C11—C12118.59 (10)
C5—C4—C6122.35 (11)C10—C11—H11A120.7
C3—C4—C6121.20 (10)C12—C11—H11A120.7
N1—C5—C4121.94 (10)C11—C12—C13120.61 (11)
N1—C5—H5A119.0C11—C12—H12A119.7
C4—C5—H5A119.0C13—C12—H12A119.7
C4—C6—H6A109.5C8—C13—C12119.93 (10)
C4—C6—H6B109.5C8—C13—H13A120.0
H6A—C6—H6B109.5C12—C13—H13A120.0
C5—N1—C1—N2179.47 (10)O2—C7—C8—C91.54 (15)
C5—N1—C1—C20.06 (16)O1—C7—C8—C9177.53 (10)
N2—C1—C2—C3179.39 (11)C13—C8—C9—C100.51 (16)
N1—C1—C2—C30.12 (16)C7—C8—C9—C10179.45 (9)
C1—C2—C3—C40.16 (18)C8—C9—C10—C111.46 (16)
C2—C3—C4—C50.13 (17)C8—C9—C10—Cl1178.02 (8)
C2—C3—C4—C6179.96 (11)C9—C10—C11—C121.01 (17)
C1—N1—C5—C40.03 (17)Cl1—C10—C11—C12178.47 (9)
C3—C4—C5—N10.06 (16)C10—C11—C12—C130.39 (18)
C6—C4—C5—N1179.89 (10)C9—C8—C13—C120.85 (17)
O2—C7—C8—C13178.50 (10)C7—C8—C13—C12179.19 (10)
O1—C7—C8—C132.43 (16)C11—C12—C13—C81.32 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N1···O11.00 (2)1.68 (2)2.6716 (13)174 (2)
N2—H1N2···O20.946 (19)1.820 (19)2.7618 (15)173.0 (19)
N2—H2N2···O1i0.90 (2)1.95 (2)2.8526 (14)174.0 (17)
C2—H2A···O2ii0.952.523.2104 (15)130
Symmetry codes: (i) x, y+3/2, z+1/2; (ii) x+1, y+1/2, z+3/2.

Experimental details

Crystal data
Chemical formulaC6H9N2+·C7H4ClO2
Mr264.70
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)9.0318 (11), 11.6590 (14), 12.1166 (15)
β (°) 101.521 (2)
V3)1250.2 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.30
Crystal size (mm)0.53 × 0.31 × 0.22
Data collection
DiffractometerBruker SMART APEXII DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.856, 0.936
No. of measured, independent and
observed [I > 2σ(I)] reflections
13594, 3629, 3201
Rint0.031
(sin θ/λ)max1)0.705
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.115, 1.06
No. of reflections3629
No. of parameters176
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.48, 0.33

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···O11.00 (2)1.68 (2)2.6716 (13)174 (2)
N2—H1N2···O20.946 (19)1.820 (19)2.7618 (15)173.0 (19)
N2—H2N2···O1i0.90 (2)1.95 (2)2.8526 (14)174.0 (17)
C2—H2A···O2ii0.952.523.2104 (15)130
Symmetry codes: (i) x, y+3/2, z+1/2; (ii) x+1, y+1/2, z+3/2.
 

Footnotes

Thomson Reuters ResearcherID: A-5599-2009.

Acknowledgements

The authors thank the Malaysian Government and Universiti Sains Malaysia (USM) for the research facilities and Fundamental Research Grant Scheme (FRGS) No. 203/PFIZIK/6711171 to conduct this work. KT thanks The Academy of Sciences for the Developing World and USM for a TWAS–USM fellowship.

References

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