organic compounds
2-Aminoanilinium 2-carboxyacetate
aDepartment of Chemical & Environmental Engineering, Anyang Institute of Technology, Anyang 455000, People's Republic of China
*Correspondence e-mail: ayitzhao@yahoo.com.cn
In the 6H9N2+·C3H3O4−, all the amino H atoms are involved in intermolecular N—H⋯O hydrogen bonds, which link the ions into double chains parallel to [101]. In the anion, an intramolecular O—H⋯O hydrogen bond is observed.
of the title compound, CRelated literature
For background to pharmaceutical applications and growth of co-crystals, see: Almarsson & Zaworotko (2004); Blagden et al. (2008); Vishweshwar et al. (2006); Kapildev et al. (2011); Schultheiss & Newman (2009).
Experimental
Crystal data
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Refinement
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Data collection: CrystalClear (Rigaku, 2005); cell CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL .
Supporting information
10.1107/S160053681102544X/rz2617sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681102544X/rz2617Isup2.hkl
Supporting information file. DOI: 10.1107/S160053681102544X/rz2617Isup3.cml
A mixture of benzene-1,2-diamine (2.0 mmol), malonic acid (2.0 mmol) in distilled water (20 ml) was added into a 50 ml flask and refluxed for 5 hours, then cooled and filtrated. The solution was evaporated slowly in the air. Colourless block crystals suitable for X-ray analysis were obtained after one week.
All H atoms attached to C atoms were fixed geometrically and treated as riding with C-H = 0.93–0.97 Å and with Uiso(H) = 1.2 Ueq(C). The amine and carboxylic H atoms were located in a difference Fourier map and refined freely. In the last stage of the
they were restrained with the H—N1 = 0.90 (2) Å, H—N2 = 0.89 (2) Å and H—O4 = 0.82 (2) Å, and with Uiso(H) = 1.5 Ueq(N1, O4) or 1.2 Ueq(N2).Data collection: CrystalClear (Rigaku, 2005); cell
CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008.Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 30% probability level. | |
Fig. 2. The crystal packing of the title compound viewed along the b axis, showing a double chain formed by intermolecular hydrogen bonds (dashed line). Hydrogen atoms not involved in hydrogen bonding are omitted for clarity. |
C6H9N2+·C3H3O4− | F(000) = 448 |
Mr = 212.21 | Dx = 1.399 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 2310 reflections |
a = 12.735 (3) Å | θ = 1.9–27.5° |
b = 5.7448 (11) Å | µ = 0.11 mm−1 |
c = 14.429 (3) Å | T = 298 K |
β = 107.38 (3)° | Block, colourless |
V = 1007.4 (3) Å3 | 0.30 × 0.25 × 0.15 mm |
Z = 4 |
Rigaku Mercury2 diffractometer | 2310 independent reflections |
Radiation source: fine-focus sealed tube | 2027 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.026 |
Detector resolution: 13.6612 pixels mm-1 | θmax = 27.5°, θmin = 1.9° |
CCD profile fitting scans | h = −16→16 |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | k = −7→7 |
Tmin = 0.910, Tmax = 1.000 | l = −18→18 |
10297 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.129 | H-atom parameters constrained |
S = 1.14 | w = 1/[σ2(Fo2) + (0.0733P)2 + 0.1065P] where P = (Fo2 + 2Fc2)/3 |
2310 reflections | (Δ/σ)max < 0.001 |
137 parameters | Δρmax = 0.29 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
C6H9N2+·C3H3O4− | V = 1007.4 (3) Å3 |
Mr = 212.21 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 12.735 (3) Å | µ = 0.11 mm−1 |
b = 5.7448 (11) Å | T = 298 K |
c = 14.429 (3) Å | 0.30 × 0.25 × 0.15 mm |
β = 107.38 (3)° |
Rigaku Mercury2 diffractometer | 2310 independent reflections |
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) | 2027 reflections with I > 2σ(I) |
Tmin = 0.910, Tmax = 1.000 | Rint = 0.026 |
10297 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.129 | H-atom parameters constrained |
S = 1.14 | Δρmax = 0.29 e Å−3 |
2310 reflections | Δρmin = −0.25 e Å−3 |
137 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
O2 | 0.61965 (7) | 0.52957 (17) | 0.59590 (7) | 0.0380 (3) | |
N1 | 0.58132 (8) | 0.80154 (19) | 0.41942 (8) | 0.0318 (3) | |
H1A | 0.5336 | 0.8376 | 0.3623 | 0.048* | |
H1B | 0.5997 | 0.9297 | 0.4552 | 0.048* | |
H1C | 0.5506 | 0.6998 | 0.4500 | 0.048* | |
O4 | 0.78587 (8) | 0.72834 (17) | 0.69666 (7) | 0.0407 (3) | |
H4 | 0.7231 | 0.6862 | 0.6670 | 0.061* | |
O3 | 0.94464 (8) | 0.5435 (2) | 0.74114 (7) | 0.0458 (3) | |
O1 | 0.62897 (9) | 0.1692 (2) | 0.54632 (9) | 0.0538 (3) | |
C1 | 0.67983 (9) | 0.6987 (2) | 0.40414 (8) | 0.0286 (3) | |
C9 | 0.84796 (9) | 0.5516 (2) | 0.69323 (8) | 0.0303 (3) | |
C7 | 0.67270 (10) | 0.3478 (2) | 0.58610 (8) | 0.0320 (3) | |
C8 | 0.79755 (9) | 0.3559 (2) | 0.62487 (9) | 0.0307 (3) | |
H8A | 0.8226 | 0.2101 | 0.6580 | 0.037* | |
H8B | 0.8263 | 0.3641 | 0.5698 | 0.037* | |
C6 | 0.77981 (11) | 0.8061 (3) | 0.44260 (10) | 0.0390 (3) | |
H6A | 0.7845 | 0.9435 | 0.4777 | 0.047* | |
N2 | 0.56773 (12) | 0.3929 (3) | 0.31118 (11) | 0.0569 (4) | |
H2A | 0.5601 | 0.2518 | 0.2828 | 0.068* | |
H2B | 0.5078 | 0.4222 | 0.3303 | 0.068* | |
C2 | 0.66864 (11) | 0.4931 (2) | 0.35095 (9) | 0.0342 (3) | |
C3 | 0.76464 (13) | 0.3975 (3) | 0.33892 (10) | 0.0436 (4) | |
H3A | 0.7607 | 0.2596 | 0.3043 | 0.052* | |
C4 | 0.86492 (13) | 0.5041 (3) | 0.37757 (12) | 0.0515 (4) | |
H4A | 0.9277 | 0.4369 | 0.3688 | 0.062* | |
C5 | 0.87378 (12) | 0.7085 (3) | 0.42893 (12) | 0.0513 (4) | |
H5A | 0.9418 | 0.7804 | 0.4542 | 0.062* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O2 | 0.0268 (4) | 0.0449 (5) | 0.0408 (5) | 0.0064 (4) | 0.0079 (4) | 0.0038 (4) |
N1 | 0.0269 (5) | 0.0348 (6) | 0.0329 (5) | 0.0024 (4) | 0.0074 (4) | −0.0021 (4) |
O4 | 0.0355 (5) | 0.0373 (5) | 0.0450 (5) | 0.0022 (4) | 0.0055 (4) | −0.0112 (4) |
O3 | 0.0282 (5) | 0.0568 (6) | 0.0444 (6) | −0.0005 (4) | −0.0012 (4) | −0.0073 (5) |
O1 | 0.0412 (6) | 0.0616 (7) | 0.0592 (7) | −0.0177 (5) | 0.0160 (5) | −0.0293 (6) |
C1 | 0.0259 (6) | 0.0320 (6) | 0.0282 (6) | 0.0026 (4) | 0.0085 (4) | 0.0031 (4) |
C9 | 0.0265 (6) | 0.0365 (6) | 0.0275 (6) | −0.0006 (5) | 0.0075 (4) | 0.0004 (5) |
C7 | 0.0277 (6) | 0.0421 (7) | 0.0262 (5) | −0.0027 (5) | 0.0082 (4) | −0.0023 (5) |
C8 | 0.0274 (6) | 0.0325 (6) | 0.0324 (6) | 0.0012 (5) | 0.0092 (5) | −0.0031 (5) |
C6 | 0.0319 (6) | 0.0423 (7) | 0.0414 (7) | −0.0037 (5) | 0.0088 (5) | −0.0007 (6) |
N2 | 0.0508 (8) | 0.0546 (8) | 0.0686 (9) | −0.0159 (6) | 0.0229 (7) | −0.0303 (7) |
C2 | 0.0384 (7) | 0.0349 (7) | 0.0314 (6) | 0.0004 (5) | 0.0134 (5) | 0.0004 (5) |
C3 | 0.0542 (9) | 0.0426 (8) | 0.0409 (7) | 0.0124 (7) | 0.0246 (6) | 0.0031 (6) |
C4 | 0.0425 (8) | 0.0685 (11) | 0.0513 (9) | 0.0203 (7) | 0.0259 (7) | 0.0154 (8) |
C5 | 0.0279 (7) | 0.0690 (11) | 0.0571 (9) | −0.0014 (7) | 0.0128 (6) | 0.0069 (8) |
O2—C7 | 1.2742 (16) | C8—H8A | 0.9700 |
N1—C1 | 1.4618 (15) | C8—H8B | 0.9700 |
N1—H1A | 0.8900 | C6—C5 | 1.388 (2) |
N1—H1B | 0.8900 | C6—H6A | 0.9300 |
N1—H1C | 0.8900 | N2—C2 | 1.3679 (19) |
O4—C9 | 1.2969 (16) | N2—H2A | 0.9003 |
O4—H4 | 0.8221 | N2—H2B | 0.9008 |
O3—C9 | 1.2195 (15) | C2—C3 | 1.3978 (19) |
O1—C7 | 1.2253 (17) | C3—C4 | 1.375 (2) |
C1—C6 | 1.3737 (18) | C3—H3A | 0.9300 |
C1—C2 | 1.3924 (18) | C4—C5 | 1.375 (3) |
C9—C8 | 1.5069 (17) | C4—H4A | 0.9300 |
C7—C8 | 1.5205 (17) | C5—H5A | 0.9300 |
C1—N1—H1A | 109.5 | C7—C8—H8B | 108.0 |
C1—N1—H1B | 109.5 | H8A—C8—H8B | 107.2 |
H1A—N1—H1B | 109.5 | C1—C6—C5 | 119.72 (14) |
C1—N1—H1C | 109.5 | C1—C6—H6A | 120.1 |
H1A—N1—H1C | 109.5 | C5—C6—H6A | 120.1 |
H1B—N1—H1C | 109.5 | C2—N2—H2A | 122.0 |
C9—O4—H4 | 105.0 | C2—N2—H2B | 124.6 |
C6—C1—C2 | 122.23 (12) | H2A—N2—H2B | 108.7 |
C6—C1—N1 | 119.42 (12) | N2—C2—C1 | 121.12 (12) |
C2—C1—N1 | 118.34 (11) | N2—C2—C3 | 121.96 (13) |
O3—C9—O4 | 122.15 (12) | C1—C2—C3 | 116.91 (13) |
O3—C9—C8 | 120.19 (12) | C4—C3—C2 | 121.01 (14) |
O4—C9—C8 | 117.62 (10) | C4—C3—H3A | 119.5 |
O1—C7—O2 | 123.81 (12) | C2—C3—H3A | 119.5 |
O1—C7—C8 | 118.48 (12) | C5—C4—C3 | 121.04 (13) |
O2—C7—C8 | 117.71 (11) | C5—C4—H4A | 119.5 |
C9—C8—C7 | 117.25 (10) | C3—C4—H4A | 119.5 |
C9—C8—H8A | 108.0 | C4—C5—C6 | 119.08 (14) |
C7—C8—H8A | 108.0 | C4—C5—H5A | 120.5 |
C9—C8—H8B | 108.0 | C6—C5—H5A | 120.5 |
O3—C9—C8—C7 | 165.75 (12) | C6—C1—C2—C3 | 0.67 (19) |
O4—C9—C8—C7 | −16.10 (16) | N1—C1—C2—C3 | −179.06 (11) |
O1—C7—C8—C9 | −165.98 (12) | N2—C2—C3—C4 | 178.41 (14) |
O2—C7—C8—C9 | 14.93 (16) | C1—C2—C3—C4 | −0.5 (2) |
C2—C1—C6—C5 | −0.2 (2) | C2—C3—C4—C5 | −0.2 (2) |
N1—C1—C6—C5 | 179.56 (12) | C3—C4—C5—C6 | 0.8 (2) |
C6—C1—C2—N2 | −178.23 (14) | C1—C6—C5—C4 | −0.6 (2) |
N1—C1—C2—N2 | 2.05 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O3i | 0.89 | 1.90 | 2.7865 (17) | 171 |
N1—H1B···O1ii | 0.89 | 1.86 | 2.7420 (15) | 170 |
N2—H2A···O3iii | 0.90 | 2.21 | 2.9693 (18) | 142 |
N2—H2B···O2iv | 0.90 | 2.21 | 3.0988 (18) | 169 |
N1—H1C···O2 | 0.89 | 2.25 | 2.9019 (15) | 130 |
O4—H4···O2 | 0.82 | 1.67 | 2.4616 (15) | 161 |
Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) x, y+1, z; (iii) x−1/2, −y+1/2, z−1/2; (iv) −x+1, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C6H9N2+·C3H3O4− |
Mr | 212.21 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 298 |
a, b, c (Å) | 12.735 (3), 5.7448 (11), 14.429 (3) |
β (°) | 107.38 (3) |
V (Å3) | 1007.4 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.11 |
Crystal size (mm) | 0.30 × 0.25 × 0.15 |
Data collection | |
Diffractometer | Rigaku Mercury2 diffractometer |
Absorption correction | Multi-scan (CrystalClear; Rigaku, 2005) |
Tmin, Tmax | 0.910, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10297, 2310, 2027 |
Rint | 0.026 |
(sin θ/λ)max (Å−1) | 0.650 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.129, 1.14 |
No. of reflections | 2310 |
No. of parameters | 137 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.29, −0.25 |
Computer programs: CrystalClear (Rigaku, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O3i | 0.89 | 1.90 | 2.7865 (17) | 171 |
N1—H1B···O1ii | 0.89 | 1.86 | 2.7420 (15) | 170 |
N2—H2A···O3iii | 0.90 | 2.21 | 2.9693 (18) | 142 |
N2—H2B···O2iv | 0.90 | 2.21 | 3.0988 (18) | 169 |
N1—H1C···O2 | 0.89 | 2.25 | 2.9019 (15) | 130 |
O4—H4···O2 | 0.82 | 1.67 | 2.4616 (15) | 161 |
Symmetry codes: (i) x−1/2, −y+3/2, z−1/2; (ii) x, y+1, z; (iii) x−1/2, −y+1/2, z−1/2; (iv) −x+1, −y+1, −z+1. |
Acknowledgements
This work was supported by the start-up fund of Anyang Institute of Technology, China.
References
Almarsson, O. & Zaworotko, M. J. (2004). Chem. Commun. 17, 1889–1896. Web of Science CrossRef Google Scholar
Blagden, N., Berry, D. J., Parkin, A., Javed, H., Ibrahim, A., Gavan, P. T., De Matos, L. L. & Seaton, C. C. (2008). New J. Chem. 32, 1659–1672. Web of Science CSD CrossRef CAS Google Scholar
Kapildev, K. A., Nitin, G. T. & Raj, S. (2011). Mol. Pharm. 8, 982–989. Web of Science PubMed Google Scholar
Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan. Google Scholar
Schultheiss, N. & Newman, A. (2009). Cryst. Growth Des. 9, 2950–2967. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Vishweshwar, P., McMahon, J. A., Bis, J. A. & Zaworotko, M. J. (2006). J. Pharm. Sci. 95, 499–516. Web of Science CrossRef PubMed CAS 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.
Molecular co-crystals are becoming increasingly important within the pharmaceutical industry as an alternative source of new solid crystalline materials with the potential to provide optimal physical properties whilst retaining the chemical properties of the cocrystal components (Almarsson & Zaworotko, 2004; Blagden et al., 2008; Vishweshwar et al., 2006). Physicochemical properties such as the melting point, stability and solubility of an active pharmaceutical ingredient can be tuned through co-crystal formulation (Kapildev et al., 2011; Schultheiss & Newman, 2009). Co-crystal synthesis often relies on the acid-amide H-bonds interactions. Herein, we report the crystal structure of the title compound, 2-aminoanilinium 2-carboxyacetate.
The asymmetric unit of the title compound is composed of one 2-aminoanilinium cation and one 2-carboxyacetate anion (Fig. 1). The amine N1 atom is protonated and one of the carboxyl groups (C7/O1/O2) is deprotonated. The geometric parameters of the title compound are in the normal range. In the crystal structure, all the amino H atoms are involved in intermolecular N—H···O hydrogen bonding interactions with carboxylic O atoms, linking the ions into double chains parallel to the [101] direction (Table 1; Fig. 2). The conformation of the anion is stabilized by an intramolecular O—H···O hydrogen bond (Table 1).