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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 67| Part 12| December 2011| Page o3222
https://doi.org/10.1107/S1600536811046113

4-Chloro-2-nitro­benzoic acid–pyrazine (2/1)

Kazuma Gotoha and Hiroyuki Ishidaa*

aDepartment of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan
*Correspondence e-mail: ishidah@cc.okayama-u.ac.jp

(Received 17 October 2011; accepted 2 November 2011; online 9 November 2011)

In the title co-crystal, 2C7H4ClNO4·C4H4N2, the pyrazine mol­ecule is located on an inversion centre, so that the asymmetric unit consists of one mol­ecule of 4-chloro-2-nitro­benzoic acid and a half-mol­ecule of pyrazine. The components are connected by O—H⋯N and C—H⋯O hydrogen bonds, forming a 2:1 unit. In the hydrogen-bonded unit, the dihedral angle between the pyrazine ring and the benzene ring of the benzoic acid is 16.55 (4)°. The units are linked by inter­molecular C—H⋯O hydrogen bonds, forming a sheet structure parallel to ([\overline{1}]04). A C—H⋯O hydrogen-bond linkage is also observed between these sheets.

Related literature

For related structures, see: Gotoh & Ishida (2009[Gotoh, K. & Ishida, H. (2009). Acta Cryst. C65, o534-o538.]); Gotoh et al. (2010[Gotoh, K., Katagiri, K. & Ishida, H. (2010). Acta Cryst. E66, o3190.]); Ishida et al. (2001[Ishida, H., Rahman, B. & Kashino, S. (2001). Acta Cryst. C57, 876-879.]).

[Scheme 1]

Experimental

Crystal data

  • 2C7H4ClNO4·C4H4N2

  • Mr = 483.22

  • Monoclinic, P 21 /c

  • a = 4.87662 (13) Å

  • b = 13.5385 (3) Å

  • c = 14.7981 (6) Å

  • β = 90.858 (2)°

  • V = 976.89 (5) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.39 mm−1

  • T = 110 K

  • 0.35 × 0.15 × 0.11 mm
Data collection

  • Rigaku R-AXIS RAPID II diffractometer

  • Absorption correction: numerical (NUMABS; Higashi, 1999[Higashi, T. (1999). NUMABS. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.904, Tmax = 0.958

  • 19734 measured reflections

  • 2833 independent reflections

  • 2535 reflections with I > 2σ(I)

  • Rint = 0.032
Refinement

  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.081

  • S = 1.07

  • 2833 reflections

  • 149 parameters

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

  • Δρmax = 0.51 e Å−3

  • Δρmin = −0.39 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O2—H2⋯N2 0.88 (2) 1.80 (2) 2.6739 (10) 178 (2)
C3—H3⋯O1i 0.95 2.51 3.4305 (12) 162
C6—H6⋯O3ii 0.95 2.59 3.4865 (13) 157
C8—H8⋯O1 0.95 2.55 3.2201 (12) 128
C9—H9⋯O3iii 0.95 2.45 3.1273 (12) 128
Symmetry codes: (i) [-x+2, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]; (ii) [-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) x-1, y, z.

Data collection: PROCESS-AUTO (Rigaku/MSC, 2004[Rigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2004[Rigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2004[Rigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811046113/fj2468sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811046113/fj2468Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811046113/fj2468Isup3.cml

checkCIF report


Comment top

The title compound was prepared in order to extend our study on D—H···A hydrogen bonding (D = N, O, or C; A = N, O or Cl) in pyridine–substituted benzoic acid systems (Gotoh & Ishida, 2009; Gotoh et al., 2010). The structures of the (1/2) compounds of pyrazine with 2-chloro-4-nitrobenzoic acid and 2-chloro-5-nitrobenzoic acid have been reported (Ishida et al., 2001).

In the crystal structure of the title compound, no acid-base interaction involving proton transfer is observed between the two components, which are linked by O—H···N and C—H···O hydrogen bonds (Table 1 and Fig. 1). In the hydrogen-bonded 1:2 unit located on an inversion centre, the dihedral angle between the pyrazine ring and the benzene ring of the benzoic acid is 16.55 (4)°. The carboxyl plane makes dihedral angles of 7.15 (11) and 22.01 (11)°, respectively, with the pyrazine and benzene rings. The dihedral angle between the nitro group and the benzene ring is 77.58 (11)°. The 1:2 units are linked by intermolecular C—H···O hydrogen bonds between the acid molecules (C3—H3···O1ii and C6—H6···O3iii; Table 1), forming a sheet parallel to the (104) plane (Fig. 2). The sheets are further linked by a C—H···O hydrogen bond (C9—H9···Oiv; Table 1), forming a three-dimensional hydrogen-bonded network.

Related literature top

For related structures, see: Gotoh & Ishida (2009); Gotoh et al. (2010); Ishida et al. (2001).

Experimental top

Single crystals were obtained by slow evaporation from an acetonitrile solution (50 ml) of 4-chloro-2-nitrobenzoic acid (0.620 g) and pyrazine (0.123 g) at room temperature.

Refinement top

C-bound H atoms were positioned geometrically (C—H = 0.95 Å) and refined as riding, with Uiso(H) = 1.2Ueq(C). The O-bound H atom was found in a difference Fourier map and refined freely. The refined O—H distance is 0.88 (2) Å.

Structure description top

The title compound was prepared in order to extend our study on D—H···A hydrogen bonding (D = N, O, or C; A = N, O or Cl) in pyridine–substituted benzoic acid systems (Gotoh & Ishida, 2009; Gotoh et al., 2010). The structures of the (1/2) compounds of pyrazine with 2-chloro-4-nitrobenzoic acid and 2-chloro-5-nitrobenzoic acid have been reported (Ishida et al., 2001).

In the crystal structure of the title compound, no acid-base interaction involving proton transfer is observed between the two components, which are linked by O—H···N and C—H···O hydrogen bonds (Table 1 and Fig. 1). In the hydrogen-bonded 1:2 unit located on an inversion centre, the dihedral angle between the pyrazine ring and the benzene ring of the benzoic acid is 16.55 (4)°. The carboxyl plane makes dihedral angles of 7.15 (11) and 22.01 (11)°, respectively, with the pyrazine and benzene rings. The dihedral angle between the nitro group and the benzene ring is 77.58 (11)°. The 1:2 units are linked by intermolecular C—H···O hydrogen bonds between the acid molecules (C3—H3···O1ii and C6—H6···O3iii; Table 1), forming a sheet parallel to the (104) plane (Fig. 2). The sheets are further linked by a C—H···O hydrogen bond (C9—H9···Oiv; Table 1), forming a three-dimensional hydrogen-bonded network.

For related structures, see: Gotoh & Ishida (2009); Gotoh et al. (2010); Ishida et al. (2001).

Computing details top

Data collection: PROCESS-AUTO (Rigaku/MSC, 2004); cell refinement: PROCESS-AUTO (Rigaku/MSC, 2004); data reduction: CrystalStructure (Rigaku/MSC, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2004) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, with the atom-labeling. Displacement ellipsoids of non-H atoms are drawn at the 50% probability level. The dashed lines indicate the O—H···N and C—H···O hydrogen bonds. [Symmetry code: (i) -x, -y + 1, -z.]
[Figure 2] Fig. 2. A packing diagram of the title compound, showing a sheet structure formed by O—H···N and C—H···O hydrogen bonds (dashed lines). [Symmetry codes: (ii) -x + 2, y + 1/2, -z + 1/2; (iii) -x + 2, y - 1/2, -z + 1/2.]
4-Chloro-2-nitrobenzoic acid–pyrazine (2/1) top
Crystal data top
2C7H4ClNO4·C4H4N2F(000) = 492.00
Mr = 483.22Dx = 1.643 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71075 Å
Hall symbol: -P 2ybcCell parameters from 16875 reflections
a = 4.87662 (13) Åθ = 3.0–30.1°
b = 13.5385 (3) ŵ = 0.39 mm−1
c = 14.7981 (6) ÅT = 110 K
β = 90.858 (2)°Block, colorless
V = 976.89 (5) Å30.35 × 0.15 × 0.11 mm
Z = 2
Data collection top
Rigaku R-AXIS RAPID II
diffractometer		2535 reflections with I > 2σ(I)
Detector resolution: 10.00 pixels mm-1Rint = 0.032
ω scansθmax = 30.0°
Absorption correction: numerical
(NUMABS; Higashi, 1999)		h = −6→6
Tmin = 0.904, Tmax = 0.958k = −19→19
19734 measured reflectionsl = −20→20
2833 independent reflections
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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.081H atoms treated by a mixture of independent and constrained refinement
S = 1.07 w = 1/[σ2(Fo2) + (0.0499P)2 + 0.2334P]
where P = (Fo2 + 2Fc2)/3
2833 reflections(Δ/σ)max = 0.001
149 parametersΔρmax = 0.51 e Å−3
0 restraintsΔρmin = −0.39 e Å−3
Crystal data top
2C7H4ClNO4·C4H4N2V = 976.89 (5) Å3
Mr = 483.22Z = 2
Monoclinic, P21/cMo Kα radiation
a = 4.87662 (13) ŵ = 0.39 mm−1
b = 13.5385 (3) ÅT = 110 K
c = 14.7981 (6) Å0.35 × 0.15 × 0.11 mm
β = 90.858 (2)°
Data collection top
Rigaku R-AXIS RAPID II
diffractometer		2833 independent reflections
Absorption correction: numerical
(NUMABS; Higashi, 1999)		2535 reflections with I > 2σ(I)
Tmin = 0.904, Tmax = 0.958Rint = 0.032
19734 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.081H atoms treated by a mixture of independent and constrained refinement
S = 1.07Δρmax = 0.51 e Å−3
2833 reflectionsΔρmin = −0.39 e Å−3
149 parameters
Special details top

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
Cl11.52398 (5)0.692432 (19)0.490381 (17)0.02257 (8)
O10.69354 (15)0.47150 (5)0.18863 (5)0.02033 (15)
O20.54429 (14)0.62747 (5)0.17436 (5)0.01875 (15)
O30.99168 (16)0.77178 (6)0.14572 (5)0.02218 (16)
O40.72288 (16)0.82806 (6)0.25018 (5)0.02337 (17)
N10.89159 (16)0.76980 (6)0.22167 (5)0.01549 (16)
N20.18864 (16)0.54745 (6)0.05617 (5)0.01577 (16)
C10.90441 (18)0.59589 (7)0.27806 (6)0.01446 (17)
C20.99232 (19)0.69339 (6)0.28474 (6)0.01377 (17)
C31.18351 (19)0.72540 (7)0.34825 (6)0.01557 (18)
H31.24160.79230.35040.019*
C41.28706 (19)0.65599 (7)0.40871 (7)0.01698 (18)
C51.2038 (2)0.55818 (7)0.40559 (7)0.01984 (19)
H51.27570.51170.44780.024*
C61.0143 (2)0.52883 (7)0.34015 (7)0.01845 (19)
H60.95840.46170.33760.022*
C70.70336 (18)0.55797 (7)0.20900 (6)0.01475 (17)
C80.18281 (19)0.44916 (7)0.04969 (6)0.01661 (18)
H80.30990.41090.08410.020*
C90.00621 (19)0.59808 (7)0.00657 (6)0.01588 (18)
H90.00560.66820.00980.019*
H20.429 (4)0.6024 (14)0.1346 (14)0.050 (5)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.02064 (13)0.02541 (14)0.02136 (13)−0.00126 (9)−0.00925 (9)−0.00274 (9)
O10.0212 (3)0.0153 (3)0.0243 (4)−0.0027 (3)−0.0041 (3)−0.0039 (3)
O20.0174 (3)0.0171 (3)0.0215 (4)0.0001 (3)−0.0072 (3)−0.0038 (3)
O30.0290 (4)0.0224 (4)0.0151 (3)−0.0004 (3)0.0005 (3)0.0007 (3)
O40.0249 (4)0.0182 (3)0.0271 (4)0.0068 (3)0.0004 (3)−0.0010 (3)
N10.0167 (4)0.0131 (3)0.0166 (4)−0.0019 (3)−0.0031 (3)−0.0010 (3)
N20.0148 (3)0.0181 (4)0.0144 (4)−0.0023 (3)−0.0012 (3)−0.0013 (3)
C10.0139 (4)0.0135 (4)0.0160 (4)−0.0009 (3)−0.0011 (3)−0.0025 (3)
C20.0138 (4)0.0135 (4)0.0139 (4)0.0011 (3)−0.0007 (3)−0.0008 (3)
C30.0150 (4)0.0150 (4)0.0167 (4)−0.0015 (3)−0.0012 (3)−0.0025 (3)
C40.0146 (4)0.0199 (4)0.0163 (4)0.0005 (3)−0.0037 (3)−0.0024 (3)
C50.0207 (4)0.0179 (4)0.0208 (4)0.0015 (4)−0.0059 (4)0.0014 (4)
C60.0200 (4)0.0138 (4)0.0215 (4)−0.0005 (3)−0.0036 (3)−0.0002 (3)
C70.0131 (4)0.0160 (4)0.0151 (4)−0.0022 (3)0.0002 (3)−0.0017 (3)
C80.0160 (4)0.0178 (4)0.0159 (4)−0.0004 (3)−0.0019 (3)−0.0006 (3)
C90.0165 (4)0.0154 (4)0.0157 (4)−0.0017 (3)−0.0003 (3)−0.0010 (3)
Geometric parameters (Å, º) top
Cl1—C41.7313 (10)C2—C31.3836 (12)
O1—C71.2095 (11)C3—C41.3875 (13)
O2—C71.3183 (11)C3—H30.9500
O2—H20.88 (2)C4—C51.3855 (14)
O3—N11.2323 (11)C5—C61.3866 (13)
O4—N11.2195 (11)C5—H50.9500
N1—C21.4727 (12)C6—H60.9500
N2—C91.3343 (12)C8—C9i1.3888 (13)
N2—C81.3344 (13)C8—H80.9500
C1—C21.3909 (12)C9—C8i1.3888 (13)
C1—C61.3932 (13)C9—H90.9500
C1—C71.4964 (12)
C7—O2—H2110.7 (12)C3—C4—Cl1119.32 (7)
O4—N1—O3125.45 (9)C4—C5—C6119.28 (9)
O4—N1—C2117.09 (8)C4—C5—H5120.4
O3—N1—C2117.41 (8)C6—C5—H5120.4
C9—N2—C8117.35 (8)C5—C6—C1121.31 (9)
C2—C1—C6117.15 (8)C5—C6—H6119.3
C2—C1—C7124.91 (8)C1—C6—H6119.3
C6—C1—C7117.93 (8)O1—C7—O2124.96 (9)
C3—C2—C1123.33 (8)O1—C7—C1121.69 (9)
C3—C2—N1115.18 (8)O2—C7—C1113.35 (8)
C1—C2—N1121.47 (8)N2—C8—C9i121.03 (8)
C2—C3—C4117.45 (9)N2—C8—H8119.5
C2—C3—H3121.3C9i—C8—H8119.5
C4—C3—H3121.3N2—C9—C8i121.62 (9)
C5—C4—C3121.48 (9)N2—C9—H9119.2
C5—C4—Cl1119.20 (7)C8i—C9—H9119.2
C6—C1—C2—C31.03 (14)C3—C4—C5—C60.51 (15)
C7—C1—C2—C3−178.46 (9)Cl1—C4—C5—C6−179.92 (8)
C6—C1—C2—N1179.18 (9)C4—C5—C6—C1−0.57 (15)
C7—C1—C2—N1−0.31 (14)C2—C1—C6—C5−0.16 (15)
O4—N1—C2—C3−77.08 (11)C7—C1—C6—C5179.36 (9)
O3—N1—C2—C3100.39 (10)C2—C1—C7—O1157.90 (10)
O4—N1—C2—C1104.62 (10)C6—C1—C7—O1−21.58 (14)
O3—N1—C2—C1−77.91 (11)C2—C1—C7—O2−22.11 (13)
C1—C2—C3—C4−1.09 (14)C6—C1—C7—O2158.41 (9)
N1—C2—C3—C4−179.35 (8)C9—N2—C8—C9i−0.01 (15)
C2—C3—C4—C50.29 (15)C8—N2—C9—C8i0.01 (15)
C2—C3—C4—Cl1−179.28 (7)
Symmetry code: (i) −x, −y+1, −z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N20.88 (2)1.80 (2)2.6739 (10)178 (2)
C3—H3···O1ii0.952.513.4305 (12)162
C6—H6···O3iii0.952.593.4865 (13)157
C8—H8···O10.952.553.2201 (12)128
C9—H9···O3iv0.952.453.1273 (12)128
Symmetry codes: (ii) −x+2, y+1/2, −z+1/2; (iii) −x+2, y−1/2, −z+1/2; (iv) x−1, y, z.

Experimental details

Crystal data
Chemical formula2C7H4ClNO4·C4H4N2
Mr483.22
Crystal system, space groupMonoclinic, P21/c
Temperature (K)110
a, b, c (Å)4.87662 (13), 13.5385 (3), 14.7981 (6)
β (°) 90.858 (2)
V (Å3)976.89 (5)
Z2
Radiation typeMo Kα
µ (mm−1)0.39
Crystal size (mm)0.35 × 0.15 × 0.11
Data collection
DiffractometerRigaku R-AXIS RAPID II
Absorption correctionNumerical
(NUMABS; Higashi, 1999)
Tmin, Tmax0.904, 0.958
No. of measured, independent and
observed [I > 2σ(I)] reflections		19734, 2833, 2535
Rint0.032
(sin θ/λ)max (Å−1)0.703
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.029, 0.081, 1.07
No. of reflections2833
No. of parameters149
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.51, −0.39

Computer programs: PROCESS-AUTO (Rigaku/MSC, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), CrystalStructure (Rigaku/MSC, 2004) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···N20.88 (2)1.80 (2)2.6739 (10)178 (2)
C3—H3···O1i0.952.513.4305 (12)162
C6—H6···O3ii0.952.593.4865 (13)157
C8—H8···O10.952.553.2201 (12)128
C9—H9···O3iii0.952.453.1273 (12)128
Symmetry codes: (i) −x+2, y+1/2, −z+1/2; (ii) −x+2, y−1/2, −z+1/2; (iii) x−1, y, z.
 

Acknowledgements

This work was supported by a Grant-in-Aid for Scientific Research (C) (No. 22550013) from the Japan Society for the Promotion of Science.

References

First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
 First citationGotoh, K. & Ishida, H. (2009). Acta Cryst. C65, o534–o538.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationGotoh, K., Katagiri, K. & Ishida, H. (2010). Acta Cryst. E66, o3190.  Web of Science CSD CrossRef IUCr Journals Google Scholar
 First citationHigashi, T. (1999). NUMABS. Rigaku Corporation, Tokyo, Japan.  Google Scholar
 First citationIshida, H., Rahman, B. & Kashino, S. (2001). Acta Cryst. C57, 876–879.  Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
 First citationRigaku/MSC. (2004). PROCESS-AUTO and CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.  Google Scholar
 First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
 First citationSpek, A. L. (2009). Acta Cryst. D65, 148–155.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 12| December 2011| Page o3222
https://doi.org/10.1107/S1600536811046113
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