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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 3| March 2010| Page o578
doi:10.1107/S1600536810004447

2-Amino-5-chloro­pyridine–benzoic acid (1/1)

Madhukar Hemamalinia and Hoong-Kun Funa*‡

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

(Received 1 February 2010; accepted 4 February 2010; online 10 February 2010)

In the title compound, C5H5ClN2·C7H6O2, the carboxyl group of the benzoic acid mol­ecule is twisted away from the attached ring by 14.22 (7)°. In the crystal, the 2-amino-5-chloro­pyridine mol­ecules inter­act with the carboxyl groups of benzoic acid mol­ecules through N—H⋯O and O—H⋯N hydrogen bonds, forming cyclic R22(8) hydrogen-bonded motifs, and linking the mol­ecules into chains parallel to the [001] direction. Neighbouring 2-amino-5-chloro­pyridine mol­ecules are also centrosymmetrically paired through C—H⋯Cl hydrogen bonds, forming another R22(8) motif. The crystal structure is further stabilized by weak C—H⋯O hydrogen bonds.

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.]); 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.]); Lynch & Jones (2004[Lynch, D. E. & Jones, G. D. (2004). Acta Cryst. B60, 748-754.]). For reference 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-S19.]). 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

  • C5H5ClN2·C7H6O2

  • Mr = 250.68

  • Monoclinic, P 21 /c

  • a = 17.6114 (19) Å

  • b = 5.3442 (6) Å

  • c = 12.4774 (13) Å

  • β = 100.161 (2)°

  • V = 1155.9 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.32 mm−1

  • T = 100 K

  • 0.55 × 0.25 × 0.07 mm
Data collection

  • Bruker SMART 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 = 0.844, Tmax = 0.979

  • 11852 measured reflections

  • 3331 independent reflections

  • 2802 reflections with > 2(I)

  • Rint = 0.025
Refinement

  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.111

  • S = 1.12

  • 3331 reflections

  • 198 parameters

  • All H-atom parameters refined

  • Δρmax = 0.46 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H1O2⋯N1i 0.98 (2) 1.65 (2) 2.629 (1) 175 (2)
N2—H1N2⋯O1ii 0.88 (2) 2.04 (2) 2.898 (2) 165.4 (18)
N2—H2N2⋯O2iii 0.88 (2) 2.37 (2) 3.231 (2) 165.8 (17)
C3—H3⋯Cl1iv 0.99 (2) 2.82 (2) 3.780 (2) 163.4 (16)
C6—H6⋯O1v 0.91 (2) 2.58 (2) 3.095 (2) 116.3 (15)
Symmetry codes: (i) x, y+1, z; (ii) x, y-1, z; (iii) [x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iv) -x, -y+1, -z; (v) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810004447/wn2376sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810004447/wn2376Isup2.hkl

checkCIF report


Comment top

Pyridine and its derivatives play an important role in heterocyclic chemistry (Pozharski et al., 1997; Katritzky et al., 1996). Pyridine and its substituted derivatives are often involved in hydrogen-bond interactions (Jeffrey & Saenger, 1991; Jeffrey, 1997; Scheiner, 1997). The adducts of carboxylic acids with the 2-aminoheterocylic ring system form a graph-set motif R22(8) (Lynch & Jones, 2004). In the present study, the hydrogen-bonding patterns in the 2-amino-5-chloropyridine benzoic acid (1/1) cocrystal, are investigated.

The asymmetric unit (Fig. 1), contains one 2-amino-5-chloropyridine molecule and one benzoic acid molecule. The 2-amino-5-chloropyridine molecule is planar, with a maximum deviation of 0.002 (1) Å for atom N1. The carboxyl group of the benzoic acid molecule is twisted away from the attached ring by 14.22 (7)° . The bond lengths (Allen et al., 1987) and angles are normal.

In the crystal packing (Fig. 2), the 2-amino-5-chloropyridine molecules interact with the carboxyl group of benzoic acid molecules through N—H···O and O—H···N hydrogen bonds, forming a cyclic hydrogen-bonded motif R22(8) (Bernstein et al., 1995), and linking the molecules into chains parallel to the [001] direction. Neighbouring 2-amino-5-chloropyridine molecules are also centrosymmetrically paired through C—H···Cl hydrogen bonds, forming another R22(8) motif. The crystal structure is further stabilized by weak C6—H6···O1 (Table 1) hydrogen bonds.

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 & Saenger (1991); Jeffrey (1997); Scheiner (1997). For hydrogen-bond motifs, see: Bernstein et al. (1995); Lynch & Jones (2004). For reference 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-chloropyridine (65 mg, Aldrich) and benzoic acid (61 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

All the H atoms were located in a difference Fourier map and allowed to refine freely [N—H = 0.88 (2) Å, O—H = 0.98 (2) Å, C—H = 0.91 (2) - 1.02 (2) Å].

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. Hydrogen atoms are shown as spheres of arbitrary radius.
[Figure 2] Fig. 2. The crystal packing of the title compound, showing hydrogen-bonded (dashed lines) networks. Hydrogen atoms not involved in hydrogen bonding have been omitted.
2-Amino-5-chloropyridine–benzoic acid (1/1) top
Crystal data top
C5H5ClN2·C7H6O2F(000) = 520
Mr = 250.68Dx = 1.440 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5100 reflections
a = 17.6114 (19) Åθ = 2.4–30.0°
b = 5.3442 (6) ŵ = 0.32 mm−1
c = 12.4774 (13) ÅT = 100 K
β = 100.161 (2)°Plate, colourless
V = 1155.9 (2) Å30.55 × 0.25 × 0.07 mm
Z = 4
Data collection top
Bruker SMART APEX DUO CCD area-detector
diffractometer		3331 independent reflections
Radiation source: fine-focus sealed tube2802 reflections with > 2(I)
Graphite monochromatorRint = 0.025
ϕ and ω scansθmax = 30.0°, θmin = 1.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		h = −24→24
Tmin = 0.844, Tmax = 0.979k = −7→7
11852 measured reflectionsl = −17→17
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)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111All H-atom parameters refined
S = 1.12 w = 1/[σ2(Fo2) + (0.0596P)2 + 0.2767P]
where P = (Fo2 + 2Fc2)/3
3331 reflections(Δ/σ)max < 0.001
198 parametersΔρmax = 0.46 e Å−3
0 restraintsΔρmin = −0.21 e Å−3
Crystal data top
C5H5ClN2·C7H6O2V = 1155.9 (2) Å3
Mr = 250.68Z = 4
Monoclinic, P21/cMo Kα radiation
a = 17.6114 (19) ŵ = 0.32 mm−1
b = 5.3442 (6) ÅT = 100 K
c = 12.4774 (13) Å0.55 × 0.25 × 0.07 mm
β = 100.161 (2)°
Data collection top
Bruker SMART APEX DUO CCD area-detector
diffractometer		3331 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)		2802 reflections with > 2(I)
Tmin = 0.844, Tmax = 0.979Rint = 0.025
11852 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0330 restraints
wR(F2) = 0.111All H-atom parameters refined
S = 1.12Δρmax = 0.46 e Å−3
3331 reflectionsΔρmin = −0.21 e Å−3
198 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 esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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
Cl10.029115 (18)0.29660 (7)0.17435 (3)0.02611 (11)
N10.17431 (6)−0.2004 (2)0.08617 (9)0.0197 (2)
N20.22948 (8)−0.2526 (3)−0.06737 (10)0.0270 (3)
C10.12668 (7)−0.0733 (2)0.14079 (10)0.0202 (2)
C20.08720 (7)0.1356 (2)0.09858 (10)0.0203 (2)
C30.09605 (8)0.2235 (3)−0.00426 (11)0.0232 (3)
C40.14399 (8)0.0960 (3)−0.06017 (11)0.0229 (3)
C50.18308 (7)−0.1193 (2)−0.01300 (10)0.0199 (2)
O10.30023 (6)0.33873 (19)0.06701 (7)0.0235 (2)
O20.25316 (5)0.46305 (18)0.21358 (7)0.0202 (2)
C60.35843 (7)0.1449 (3)0.34708 (10)0.0194 (2)
C70.40642 (7)−0.0304 (3)0.40807 (10)0.0226 (3)
C80.44122 (8)−0.2180 (3)0.35634 (12)0.0232 (3)
C90.42870 (8)−0.2295 (3)0.24289 (12)0.0227 (3)
C100.38163 (7)−0.0544 (2)0.18193 (10)0.0202 (2)
C110.34623 (7)0.1339 (2)0.23375 (10)0.0170 (2)
C120.29775 (7)0.3214 (2)0.16423 (10)0.0173 (2)
H10.1213 (10)−0.132 (3)0.2126 (14)0.028 (4)*
H30.0695 (11)0.375 (4)−0.0377 (16)0.040 (5)*
H40.1539 (10)0.154 (4)−0.1271 (15)0.032 (5)*
H60.3370 (10)0.270 (4)0.3810 (14)0.026 (4)*
H70.4150 (10)−0.018 (4)0.4848 (14)0.032 (5)*
H80.4762 (10)−0.344 (3)0.4016 (14)0.026 (4)*
H90.4506 (10)−0.362 (3)0.2061 (14)0.029 (4)*
H100.3722 (9)−0.058 (3)0.1028 (13)0.024 (4)*
H1O20.2262 (13)0.590 (5)0.1647 (19)0.061 (7)*
H1N20.2563 (11)−0.378 (4)−0.0353 (16)0.039 (5)*
H2N20.2443 (11)−0.186 (4)−0.1250 (16)0.033 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02624 (17)0.02425 (18)0.02760 (18)0.00709 (12)0.00407 (12)0.00036 (12)
N10.0220 (5)0.0181 (5)0.0187 (5)0.0018 (4)0.0026 (4)0.0026 (4)
N20.0345 (6)0.0266 (6)0.0217 (5)0.0075 (5)0.0096 (5)0.0059 (5)
C10.0208 (5)0.0187 (6)0.0208 (6)0.0005 (5)0.0025 (4)0.0021 (5)
C20.0185 (5)0.0186 (6)0.0228 (6)0.0008 (5)0.0011 (4)−0.0009 (5)
C30.0232 (6)0.0200 (6)0.0240 (6)0.0016 (5)−0.0028 (5)0.0040 (5)
C40.0249 (6)0.0229 (6)0.0193 (6)0.0005 (5)−0.0006 (5)0.0049 (5)
C50.0208 (5)0.0189 (6)0.0193 (5)−0.0018 (5)0.0012 (4)0.0010 (5)
O10.0320 (5)0.0243 (5)0.0148 (4)0.0045 (4)0.0059 (3)0.0020 (4)
O20.0225 (4)0.0211 (4)0.0178 (4)0.0043 (4)0.0055 (3)0.0031 (4)
C60.0207 (5)0.0203 (6)0.0182 (5)0.0006 (5)0.0063 (4)0.0022 (5)
C70.0219 (6)0.0267 (7)0.0191 (6)0.0010 (5)0.0037 (4)0.0056 (5)
C80.0197 (6)0.0206 (6)0.0291 (7)0.0010 (5)0.0034 (5)0.0065 (5)
C90.0210 (6)0.0182 (6)0.0289 (7)0.0010 (5)0.0044 (5)−0.0018 (5)
C100.0210 (5)0.0195 (6)0.0200 (5)−0.0013 (5)0.0033 (4)−0.0026 (5)
C110.0165 (5)0.0158 (5)0.0187 (5)−0.0029 (4)0.0030 (4)0.0015 (4)
C120.0179 (5)0.0167 (6)0.0172 (5)−0.0025 (4)0.0027 (4)0.0001 (4)
Geometric parameters (Å, º) top
Cl1—C21.7382 (13)O2—C121.3190 (15)
N1—C51.3454 (16)O2—H1O20.98 (2)
N1—C11.3532 (17)C6—C111.3936 (17)
N2—C51.3530 (18)C6—C71.3946 (18)
N2—H1N20.88 (2)C6—H60.907 (18)
N2—H2N20.881 (19)C7—C81.392 (2)
C1—C21.3705 (18)C7—H70.945 (17)
C1—H10.970 (18)C8—C91.395 (2)
C2—C31.4006 (19)C8—H81.015 (18)
C3—C41.368 (2)C9—C101.3854 (19)
C3—H30.99 (2)C9—H90.962 (18)
C4—C51.4149 (18)C10—C111.4005 (18)
C4—H40.936 (18)C10—H100.972 (16)
O1—C121.2250 (15)C11—C121.4913 (17)
C5—N1—C1118.92 (11)C11—C6—H6120.1 (11)
C5—N2—H1N2120.0 (13)C7—C6—H6120.1 (11)
C5—N2—H2N2119.3 (13)C8—C7—C6120.33 (12)
H1N2—N2—H2N2117.8 (18)C8—C7—H7120.9 (11)
N1—C1—C2122.21 (12)C6—C7—H7118.7 (11)
N1—C1—H1118.2 (11)C7—C8—C9119.92 (12)
C2—C1—H1119.5 (11)C7—C8—H8119.6 (10)
C1—C2—C3119.61 (12)C9—C8—H8120.5 (10)
C1—C2—Cl1120.10 (10)C10—C9—C8119.96 (12)
C3—C2—Cl1120.25 (10)C10—C9—H9119.2 (11)
C4—C3—C2118.61 (12)C8—C9—H9120.8 (11)
C4—C3—H3118.7 (11)C9—C10—C11120.26 (12)
C2—C3—H3122.6 (11)C9—C10—H10121.5 (10)
C3—C4—C5119.45 (12)C11—C10—H10118.3 (10)
C3—C4—H4121.2 (11)C6—C11—C10119.82 (12)
C5—C4—H4119.3 (11)C6—C11—C12122.12 (11)
N1—C5—N2117.98 (12)C10—C11—C12118.04 (11)
N1—C5—C4121.20 (12)O1—C12—O2123.17 (11)
N2—C5—C4120.81 (12)O1—C12—C11120.66 (11)
C12—O2—H1O2111.7 (14)O2—C12—C11116.17 (10)
C11—C6—C7119.69 (12)
C5—N1—C1—C2−0.16 (19)C6—C7—C8—C90.6 (2)
N1—C1—C2—C3−0.2 (2)C7—C8—C9—C100.0 (2)
N1—C1—C2—Cl1−178.03 (10)C8—C9—C10—C11−0.3 (2)
C1—C2—C3—C40.34 (19)C7—C6—C11—C100.60 (19)
Cl1—C2—C3—C4178.12 (10)C7—C6—C11—C12−177.84 (11)
C2—C3—C4—C5−0.04 (19)C9—C10—C11—C6−0.01 (19)
C1—N1—C5—N2−178.39 (12)C9—C10—C11—C12178.49 (11)
C1—N1—C5—C40.47 (19)C6—C11—C12—O1165.21 (12)
C3—C4—C5—N1−0.37 (19)C10—C11—C12—O1−13.25 (18)
C3—C4—C5—N2178.46 (13)C6—C11—C12—O2−14.87 (17)
C11—C6—C7—C8−0.9 (2)C10—C11—C12—O2166.67 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H1O2···N1i0.98 (2)1.65 (2)2.629 (1)175 (2)
N2—H1N2···O1ii0.88 (2)2.04 (2)2.898 (2)165.4 (18)
N2—H2N2···O2iii0.88 (2)2.37 (2)3.231 (2)165.8 (17)
C3—H3···Cl1iv0.99 (2)2.82 (2)3.780 (2)163.4 (16)
C6—H6···O1v0.91 (2)2.58 (2)3.095 (2)116.3 (15)
Symmetry codes: (i) x, y+1, z; (ii) x, y−1, z; (iii) x, −y+1/2, z−1/2; (iv) −x, −y+1, −z; (v) x, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC5H5ClN2·C7H6O2
Mr250.68
Crystal system, space groupMonoclinic, P21/c
Temperature (K)100
a, b, c (Å)17.6114 (19), 5.3442 (6), 12.4774 (13)
β (°) 100.161 (2)
V (Å3)1155.9 (2)
Z4
Radiation typeMo Kα
µ (mm−1)0.32
Crystal size (mm)0.55 × 0.25 × 0.07
Data collection
DiffractometerBruker SMART APEX DUO CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.844, 0.979
No. of measured, independent and
observed [ > 2(I)] reflections		11852, 3331, 2802
Rint0.025
(sin θ/λ)max (Å−1)0.704
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.111, 1.12
No. of reflections3331
No. of parameters198
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å−3)0.46, −0.21

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
O2—H1O2···N1i0.98 (2)1.65 (2)2.629 (1)175 (2)
N2—H1N2···O1ii0.88 (2)2.04 (2)2.898 (2)165.4 (18)
N2—H2N2···O2iii0.88 (2)2.37 (2)3.231 (2)165.8 (17)
C3—H3···Cl1iv0.99 (2)2.82 (2)3.780 (2)163.4 (16)
C6—H6···O1v0.91 (2)2.58 (2)3.095 (2)116.3 (15)
Symmetry codes: (i) x, y+1, z; (ii) x, y−1, z; (iii) x, −y+1/2, z−1/2; (iv) −x, −y+1, −z; (v) x, −y+1/2, z+1/2.
 

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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ISSN: 2056-9890
Volume 66| Part 3| March 2010| Page o578
doi:10.1107/S1600536810004447
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