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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 65| Part 8| August 2009| Pages o1839-o1840
doi:10.1107/S1600536809026427

3-Carb­oxy­anilinium hemioxalate

Lamia Bendjeddou,a* Sara Faraha and Aouatef Cherouanaa

aLaboratoire de Chimie Moléculaire, du Contrôle, de l'Environnement et des Mesures Physico-Chimiques, Faculté des Sciences Exactes, Département de Chimie, Université Mentouri de Constantine, 25000 Constantine, Algeria
*Correspondence e-mail: lamiabendjeddou@yahoo.fr

(Received 16 June 2009; accepted 7 July 2009; online 11 July 2009)

In the title compound, C7H8NO2+·0.5C2O42−, the asymmetric unit consists of an 3-carboxy­anilinium cation, and one-half of an oxalate anion, which lies on a twofold rotation axis. The crystal packing is consolidated by inter­molecular N—H⋯O and O—H⋯O hydrogen bonds. The structure is built from infinite chains of cations and oxalate anions extending parallel to the b and c axes. The crystal studied was a non-merohedral twin. The ratio of the twin components refined to 0.335 (3):0.665 (3).

Related literature

Packing motifs, common patterns and hydrogen-bond networks in pure amino acids and in their crystals with organic acids are inter­esting for crystal engineering and for understanding structure–property relationships, see: Vijayan (1998[Vijayan, M. (1998). Prog. Biophys. Mol. Biol. 52, 71-99.]); Nangia & Desiraju (1998[Nangia, A. & Desiraju, G. R. (1998). Acta Cryst. A54, 934-944.]); Desiraju (1997[Desiraju, G. R. (1997). J. Chem. Soc. Chem. Commun. pp. 1475-1482.]). For the structures of amino acid–carboxylic acid complexes, see: Bendjeddou et al. (2003[Bendjeddou, L., Cherouana, A., Dahaoui, S., Benali-Cherif, N. & Lecomte, C. (2003). Acta Cryst. E59, o649-o651.]); Cherouana et al. (2002[Cherouana, A., Benali-Cherif, N., Bendjeddou, L. & Merazig, H. (2002). Acta Cryst. E58, o1351-o1353.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L. & Orpen, A. G. (1987). J. Chem. Soc. Perkin Trans 2, pp. S1-19.]). For a description of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]). For graph-set 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.]).

[Scheme 1]

Experimental

Crystal data

  • C7H8NO2+·0.5C2O42−

  • Mr = 182.15

  • Monoclinic, C 2/c

  • a = 22.034 (3) Å

  • b = 10.779 (2) Å

  • c = 6.9927 (10) Å

  • β = 103.918 (4)°

  • V = 1612.0 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 298 K

  • 0.3 × 0.1 × 0.09 mm
Data collection

  • Nonius KappaCCD diffractometer

  • Absorption correction: none

  • 8434 measured reflections

  • 1836 independent reflections

  • 1305 reflections with > 2σ

  • Rint = 0.056
Refinement

  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.127

  • S = 1.02

  • 1836 reflections

  • 119 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
O1C—H1C⋯O2i 0.82 1.75 2.560 (4) 169
N1—H1N⋯O1ii 0.89 1.92 2.798 (2) 169
N1—H2N⋯O2Ciii 0.89 1.97 2.856 (2) 171
N1—H3N⋯O1 0.89 2.03 2.791 (2) 143
Symmetry codes: (i) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (ii) [-x+1, y, -z+{\script{3\over 2}}]; (iii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}].

Data collection: KappaCCD Reference Manual (Nonius, 1998[Nonius (1998). KappaCCD Reference Manual. Nonius BV, Delft, The Netherlands.]); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO and SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); 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: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]), PARST97 (Nardelli, 1995[Nardelli, M. (1995). J. Appl. Cryst. 28, 659.]), Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]), POVRay (Persistence of Vision Team, 2004[Persistence of Vision Team (2004). POV-RAY. Persistence of Vision Raytracer Pty Ltd, Victoria, Australia. URL: http://www.povray.org/ .]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809026427/bx2219sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809026427/bx2219Isup2.hkl

checkCIF report


Comment top

A comparative study of the packing motifs, common patterns and the hydrogen-bond networks in crystals of pure amino acids and in their crystals with organic acids is interesting for crystal engineering and for understanding structure-property relation ships (Vijayan (1998), Nangia & Desiraju (1998), Desiraju (1997)). Amino acids crystallize easily with organic acids in general and with oxalic acid in particular. These systems are interesting as molecular materials which exhibit nonlinear optical properties.

The present study, which reports the crystal structure of 3-carboxyanilinium acid with oxalic acid, (I), forms part of a series of X-ray investigations being carried out in our laboratory on amino acid-carboxylic acid complexes. The X-ray investigations on these complexes have revealed interesting and useful data regarding the ionization states of individual molecules, their stoichiometry and intermolecular aggregation patterns (Bendjeddou et al., 2003, Cherouana et al., 2002).

Fig. 1 shows the molecular structure of (I). The amino acid molecule exists in the cationic form with a positively charged amino group and uncharged carboxylic acid group. The oxalate anion is flat and completely deprotonated and lies across a crystallographic rotation axis 2. The bond lengths and angles are all normal for their types (Allen et al., 1987).

In the title compound the ions are connected via a three-dimensional N—H···O and O—H···O hydrogen bonds network (Table 1). Unexpectedly, there are no centrosymmetric hydrogen bonded dimers between the carboxylic acid groups of adjacent 3-carboxyanilinium cations which is a characteristic feature found in most salts of 3- and 4-aminobenzoic acid (Cambridge Structural Database, Version 5.29; Allen, 2002). All ammonium H atoms are involved in hydrogen bonds with two different anions and one cation. Two of these interactions link the anions and cations in an alternating fashion into extended rings along the [001] direction, which can be described by the graph-set motif R21(5) (Bernstein et al., 1995). The combination of each N—H1N···O1 and N—H3N···O1 hydrogen bonds, with the only O—H···O which is a finit chain with a D(4) motif, generates two centrosymmetric fused rings a long [001] direction which can be described by the graph-set motif R44 (22) (Fig.2). The third interaction link the cations with the carbonyl O atom into zigzag chains along the [010] direction, which can be described by the graph-set motif C(7) (Fig.3).

Related literature top

Packing motifs, common patterns and hydrogen-bond networks in pure amino acids and in their crystals with organic acids is interesting for crystal engineering and for understanding structure–property relation ships, see: Vijayan (1998); Nangia & Desiraju (1998); Desiraju (1997). For the structures of amino acid–carboxylic acid complexes, see: Bendjeddou et al. (2003); Cherouana et al. (2002). For bond-length data, see: Allen et al. (1987). For a description of the Cambridge Structural Database, see: Allen (2002). For graph-set motifs, see: Bernstein et al. (1995).

Experimental top

Brown needle-shaped single crystals of (I) were grown from a saturated aqueous solution containing m-aminobenzoic and oxalic acid in a 2:1 stoichiometric ratio.

Refinement top

All H atoms attached to C, N and O atom were fixed geometrically and treated as riding with C—H = 0.93 Å, N—H = 0.89Å and O—H = 0.82 Å with Uiso(H) = 1.2Ueq(C,N) or Uiso(H) = 1.5Ueq(O).

Owing to the initial poor refinement, the search for the possibility of a non-merohedral twinning was carried out using the TwinRotMat procedure within PLATON (Spek, 2009). The crystal appears to be twinned about (1 0 0) with the rotation matrix: 1 0 1.516 0 - 1 0 0 0 - 1 The ratio of the two twin components was refined to 0.335 (3):0.665 (3).

Computing details top

Data collection: KappaCCD Reference Manual (Nonius, 1998); cell refinement: DENZO and SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999), PARST97 (Nardelli, 1995), Mercury (Macrae et al., 2006), POVRay (Persistence of Vision Team, 2004) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The cation and anion of (I), with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as spheres of arbitrary radii. Atoms with sufix (i) are generated by crystallographic rotation axis 2.
[Figure 2] Fig. 2. A view of the two-dimensional hydrogen-bonded network parallel to the (010) plane of (I), showing the aggregation of two hydrogen-bonding motifs, R12(5) and R44(24). Hydrogen bonds are drawn as dotted lines. Atoms marked with (ii), (iii) and (iv) are at the symmetry positions (1/2 - x,1/2 - y, 1 - z), (x, y, 1 + z), (1 - x, y, 1.5 - z) respectively.
[Figure 3] Fig. 3. Projection down the a axis of the lattice of C7H8NO2 +. 0.5 C2 O4 2-, showing the formation of C(7) chains along [010]. Atom marked with (v) is at symmetry positions (1/2 - x, 1/2 + y, 1.5 - z).
3-carboxyanilinium hemioxalate top
Crystal data top
C7H8NO2+·0.5C2O42−F(000) = 760
Mr = 182.15Dx = 1.501 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 6947 reflections
a = 22.034 (3) Åθ = 1.0–27.5°
b = 10.779 (2) ŵ = 0.12 mm−1
c = 6.9927 (10) ÅT = 298 K
β = 103.918 (4)°Prism, brown
V = 1612.0 (4) Å30.3 × 0.1 × 0.09 mm
Z = 8
Data collection top
Nonius KappaCCD
diffractometer		1305 reflections with > 2σ
Radiation source: fine-focus sealed tubeRint = 0.056
Graphite monochromatorθmax = 27.5°, θmin = 5.1°
ω scansh = −28→27
8434 measured reflectionsk = −14→14
1836 independent reflectionsl = −8→9
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.050 w = 1/[σ2(Fo2) + (0.06P)2 + 0.8696P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.127(Δ/σ)max < 0.001
S = 1.02Δρmax = 0.23 e Å−3
1836 reflectionsΔρmin = −0.30 e Å−3
119 parameters
Crystal data top
C7H8NO2+·0.5C2O42−V = 1612.0 (4) Å3
Mr = 182.15Z = 8
Monoclinic, C2/cMo Kα radiation
a = 22.034 (3) ŵ = 0.12 mm−1
b = 10.779 (2) ÅT = 298 K
c = 6.9927 (10) Å0.3 × 0.1 × 0.09 mm
β = 103.918 (4)°
Data collection top
Nonius KappaCCD
diffractometer		1305 reflections with > 2σ
8434 measured reflectionsRint = 0.056
1836 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.127H-atom parameters constrained
S = 1.02Δρmax = 0.23 e Å−3
1836 reflectionsΔρmin = −0.30 e Å−3
119 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O1C0.19114 (6)0.20422 (15)0.7825 (2)0.0416 (4)
H1C0.15430.19250.78220.062*
O2C0.18039 (7)0.02007 (15)0.6332 (3)0.0454 (4)
O10.47841 (6)0.34729 (17)0.4737 (2)0.0444 (5)
O20.41945 (6)0.32562 (19)0.1690 (2)0.0511 (5)
N10.40615 (7)0.35616 (16)0.7510 (2)0.0311 (4)
H1N0.44050.34690.84730.037*
H2N0.38190.41390.78510.037*
H3N0.41670.37930.64120.037*
C20.27904 (9)0.1208 (2)0.6919 (3)0.0298 (5)
C60.37088 (10)0.0240 (2)0.6326 (3)0.0419 (6)
H60.3912−0.04620.60220.050*
C70.30879 (10)0.0167 (2)0.6429 (3)0.0363 (5)
H70.2873−0.05800.61690.044*
C30.31077 (8)0.2324 (2)0.7322 (3)0.0286 (5)
H30.29110.30180.76860.034*
C40.37232 (8)0.2388 (2)0.7174 (3)0.0283 (5)
C80.47040 (9)0.3362 (2)0.2924 (3)0.0299 (5)
C50.40230 (10)0.1354 (2)0.6675 (3)0.0378 (5)
H50.44350.14100.65750.045*
C10.21199 (9)0.1102 (2)0.7004 (3)0.0321 (5)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O1C0.0238 (7)0.0494 (10)0.0560 (10)−0.0059 (6)0.0181 (7)−0.0094 (8)
O2C0.0338 (8)0.0464 (10)0.0578 (10)−0.0126 (7)0.0145 (8)−0.0077 (8)
O10.0245 (7)0.0812 (13)0.0303 (8)−0.0043 (7)0.0121 (6)−0.0032 (8)
O20.0201 (7)0.0984 (15)0.0351 (8)−0.0040 (8)0.0073 (6)−0.0016 (9)
N10.0200 (8)0.0438 (11)0.0302 (9)−0.0009 (7)0.0075 (7)0.0004 (8)
C20.0244 (10)0.0378 (12)0.0278 (10)−0.0007 (8)0.0072 (8)0.0020 (9)
C60.0366 (12)0.0437 (14)0.0483 (13)0.0077 (10)0.0159 (11)−0.0037 (11)
C70.0367 (11)0.0375 (13)0.0363 (11)−0.0045 (10)0.0119 (9)−0.0022 (10)
C30.0231 (9)0.0363 (12)0.0276 (10)0.0022 (8)0.0082 (8)0.0002 (9)
C40.0218 (10)0.0389 (12)0.0237 (9)−0.0017 (8)0.0045 (7)0.0014 (8)
C80.0208 (10)0.0406 (12)0.0298 (10)0.0004 (8)0.0091 (8)0.0002 (9)
C50.0234 (10)0.0525 (15)0.0393 (12)0.0020 (10)0.0113 (9)−0.0004 (11)
C10.0269 (10)0.0400 (13)0.0299 (10)−0.0040 (9)0.0076 (8)0.0058 (10)
Geometric parameters (Å, º) top
O1C—C11.302 (3)C2—C11.497 (3)
O1C—H1C0.8200C6—C51.378 (3)
O2C—C11.222 (2)C6—C71.389 (3)
O1—C81.244 (3)C6—H60.9300
O2—C81.245 (2)C7—H70.9300
N1—C41.459 (3)C3—C41.386 (3)
N1—H1N0.8900C3—H30.9300
N1—H2N0.8900C4—C51.382 (3)
N1—H3N0.8900C8—C8i1.557 (4)
C2—C71.384 (3)C5—H50.9300
C2—C31.385 (3)
C1—O1C—H1C109.5C2—C3—C4118.88 (19)
C4—N1—H1N109.5C2—C3—H3120.6
C4—N1—H2N109.5C4—C3—H3120.6
H1N—N1—H2N109.5C5—C4—C3120.95 (19)
C4—N1—H3N109.5C5—C4—N1118.88 (17)
H1N—N1—H3N109.5C3—C4—N1120.16 (18)
H2N—N1—H3N109.5O1—C8—O2126.74 (19)
C7—C2—C3120.55 (18)O1—C8—C8i117.5 (2)
C7—C2—C1118.60 (19)O2—C8—C8i115.8 (2)
C3—C2—C1120.85 (18)C6—C5—C4119.77 (19)
C5—C6—C7120.0 (2)C6—C5—H5120.1
C5—C6—H6120.0C4—C5—H5120.1
C7—C6—H6120.0O2C—C1—O1C124.04 (19)
C2—C7—C6119.9 (2)O2C—C1—C2121.5 (2)
C2—C7—H7120.1O1C—C1—C2114.49 (17)
C6—C7—H7120.1
O1C—C1—C2—C3−12.3 (3)C2—C3—C4—C5−1.3 (3)
O1C—C1—C2—C7167.71 (18)N1—C4—C5—C6−179.12 (19)
O2C—C1—C2—C3167.2 (2)C3—C4—C5—C6−0.3 (3)
O2C—C1—C2—C7−12.9 (3)C4—C5—C6—C71.6 (3)
C1—C2—C3—C4−178.32 (19)C5—C6—C7—C2−1.2 (3)
C7—C2—C3—C41.7 (3)O1—C8—C8i—O1i−167.6 (2)
C1—C2—C7—C6179.58 (19)O1—C8—C8i—O2i12.1 (3)
C3—C2—C7—C6−0.4 (3)O2—C8—C8i—O1i12.1 (3)
C2—C3—C4—N1177.46 (19)O2—C8—C8i—O2i−168.3 (2)
Symmetry code: (i) −x+1, y, −z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1C—H1C···O2ii0.821.752.560 (4)169
N1—H1N···O1iii0.891.922.798 (2)169
N1—H2N···O2Civ0.891.972.856 (2)171
N1—H3N···O10.892.032.791 (2)143
Symmetry codes: (ii) −x+1/2, −y+1/2, −z+1; (iii) −x+1, y, −z+3/2; (iv) −x+1/2, y+1/2, −z+3/2.

Experimental details

Crystal data
Chemical formulaC7H8NO2+·0.5C2O42−
Mr182.15
Crystal system, space groupMonoclinic, C2/c
Temperature (K)298
a, b, c (Å)22.034 (3), 10.779 (2), 6.9927 (10)
β (°) 103.918 (4)
V (Å3)1612.0 (4)
Z8
Radiation typeMo Kα
µ (mm−1)0.12
Crystal size (mm)0.3 × 0.1 × 0.09
Data collection
DiffractometerNonius KappaCCD
diffractometer
Absorption correction–
No. of measured, independent and
observed ( > 2σ) reflections		8434, 1836, 1305
Rint0.056
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.127, 1.02
No. of reflections1836
No. of parameters119
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.23, −0.30

Computer programs: KappaCCD Reference Manual (Nonius, 1998), DENZO and SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999), PARST97 (Nardelli, 1995), Mercury (Macrae et al., 2006), POVRay (Persistence of Vision Team, 2004) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1C—H1C···O2i0.82001.75002.560 (4)169.00
N1—H1N···O1ii0.89001.92002.798 (2)169.00
N1—H2N···O2Ciii0.89001.97002.856 (2)171.00
N1—H3N···O10.89002.03002.791 (2)143.00
Symmetry codes: (i) −x+1/2, −y+1/2, −z+1; (ii) −x+1, y, −z+3/2; (iii) −x+1/2, y+1/2, −z+3/2.
 

Acknowledgements

The authors thank Dr Jean-Claude Daran of L3C for helpful discussions.

References

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ISSN: 2056-9890
Volume 65| Part 8| August 2009| Pages o1839-o1840
doi:10.1107/S1600536809026427
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