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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 10| October 2009| Pages o2468-o2469
doi:10.1107/S1600536809036095

2-Aminoterephthalic acid di­methyl ester

Jürgen Brüning,a Jan W. Batsb and Martin U. Schmidta*

aInstitute of Inorganic and Analytical Chemistry, University of Frankfurt, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany, and bInstitute of Organic Chemistry and Chemical Biology, University of Frankfurt, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany
*Correspondence e-mail: m.schmidt@chemie.uni-frankfurt.de

(Received 31 August 2009; accepted 7 September 2009; online 16 September 2009)

Single crystals of the title compound, C10H11NO4, an inter­mediate in the industrial synthesis of yellow azo pigments, were obtained from the industrial production. The mol­ecules crystallize as centrosymmetic dimers connected by two symmetry-related N—H⋯O=C hydrogen bonds. Each mol­ecule also contains an intra­molecular N—H⋯O=C hydrogen bond. The dimers form stacks along the a-axis direction. Neighbouring stacks are arranged into a herringbone structure.

Related literature

For studies on amino­terephthalic acid esters, see: Wegscheider et al. (1912[Wegscheider, R., Faltis, F., Black, S. & Huppert, O. (1912). Monatsh. Chem. 33, 141-168.]); Clark et al. (1995[Clark, A. S., Deans, B., Stevens, M. F. G., Tisdale, M. J., Wheelhouse, R. T., Denny, B. J. & Hartley, J. A. (1995). J. Med. Chem. 38, 1493-1504.]); O'Connor et al. (1999[O'Connor, S. P., Barr, K. J., Wang, L., Sorensen, B. K., Tasker, A. S., Sham, H., Ng, S.-C., Cohen, J., Devine, E., Cherian, S., Saeed, B., Zhang, H., Lee, J. Y., Warner, R., Tahir, S., Kovar, P., Ewing, P., Alder, J., Mitten, M., Leal, J., Marsh, K., Bauch, J., Hoffman, D. J., Sebti, S. M. & Rosenberg, S. H. (1999). J. Med. Chem. 42, 3701-3710.]); Lavalette et al. (2002[Lavalette, A., Lalot, T., Brigodiot, M. & Maréchal, E. (2002). Biomacromolecules, 3, 225-228.]); Jones et al. (2008[Jones, A. M., Lebl, T., Patterson, S., van Mourik, T., Früchtl, H. A., Philp, D., Slawin, A. M. Z. & Westwood, N. J. (2008). Tetrahedron, 65, 563-578.]). For syntheses wherein the title compound is used, see: Cordier & Coulet (1994[Cordier, D. & Coulet, P. R. (1994). J. Chem Soc. Perkin Trans. 2, pp. 891-894.]); Metz & Weber (1999[Metz, H. J. & Weber, J. (1999). US Patent 591057.]); Stengel-Rutkowski & Metz (2000[Stengel-Rutkowski, B. & Metz, H. J. (2000). Farbe Lack, 106, 38-42.]); Jung et al. (2001[Jung, R., Metz, H.-J., Weber, J., Schmidt, M. U., Schupp, O. & Wacker, A. (2001). European Patent EP 1188800B1.]); Herbst & Hunger (2004[Herbst, W. & Hunger, K. (2004). Industrial Organic Pigments, 3rd ed., pp. 260-264. Weinheim: Wiley-VCH.]); Schweikart et al. (2007[Schweikart, K.-H., Lerch, J.-P. & Pourcheron, L. (2007). US Patent 7384472.]). For the crystal structure of the final product, Pigment Yellow 213, see: Schmidt et al. (2009[Schmidt, M. U., Brühne, S., Wolf, A. K., Rech, A., Brüning, J., Alig, E., Fink, L., Buchsbaum, C., Glinnemann, J., van de Streek, J., Gozzo, F., Brunelli, M., Stowasser, F., Gorelik, T., Mugnaioli, E. & Kolb, U. (2009). Acta Cryst. B65, 189-199.]).

[Scheme 1]

Experimental

Crystal data

  • C10H11NO4

  • Mr = 209.20

  • Monoclinic, P 21 /c

  • a = 4.7721 (12) Å

  • b = 16.928 (5) Å

  • c = 11.841 (5) Å

  • β = 93.88 (5)°

  • V = 954.4 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 166 K

  • 0.75 × 0.32 × 0.04 mm
Data collection

  • Siemens SMART 1K CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.760, Tmax = 0.995

  • 11829 measured reflections

  • 1687 independent reflections

  • 884 reflections with I > 2σ(I)

  • Rint = 0.140
Refinement

  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.134

  • S = 0.96

  • 1687 reflections

  • 146 parameters

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

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
N1—H1A⋯O4 0.92 (4) 2.01 (4) 2.717 (4) 133 (3)
N1—H1B⋯O2i 0.95 (4) 2.14 (3) 3.016 (4) 153 (3)
Symmetry code: (i) -x, -y+1, -z.

Data collection: SMART (Siemens, 1995[Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1995[Siemens (1995). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: publCIF (Westrip, 2009[Westrip, S. P. (2009). publCIF. In preparation.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809036095/fk2004sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809036095/fk2004Isup2.hkl

checkCIF report


Comment top

2-Aminoterephthalic acid dimethyl ester (I, Fig. 1), C10H11NO4, is used in the synthesis of industrial azo pigments like Pigment Yellow 213 (Metz & Weber, 1999; Stengel-Rutkowski & Metz, 2000; Herbst & Hunger, 2004; Schmidt et al., 2009) (For synthesis of Pigment Yellow 213 see Fig. 1). Compound I is known since 1912 (Wegscheider et al.; 1912) and has been the subject of numerous investigations, e.g. as intermediate (Cordier & Coulet, 1994), antitumor drug (Clark et al.; 1995), drug against reflux disease (O'Connor et al., 1999), in synthesis of pigments (Jung et al., 2001; Herbst & Hunger, 2004; Schweikart et al., 2007), in preparation of polymers (Lavalette et al., 2002), and in parallel syntheses (Jones et al., 2008); but its crystal structure has not been determined hitherto.

In order to determine the crystal structure of compound I and to search for different crystallographic phases, hydrates or solvates, a polymorph screening was performed. Different crystallization methods were used including (1) recrystallization from various solvents and solvent mixtures by heating and subsequent slow cooling, (2) overlaying a solution of the compound by an anti-solvent, (3) diffusion of an anti-solvent into a solution of the compound via the gas phase. The solvents included the most common organic solvents, e.g. dimethylsulfoxide, N,N-dimethylacetamide, N-methylpyrrolidone, ethers, esters, alcohols as well as acids, bases and water. According to X-ray powder diffraction no additional phases were formed.

Single crystals were obtained from technical synthesis. The structure of the molecule is shown in Fig. 2. The central six-membered ring is planar [mean deviation from best plane: 0.002 (2) Å]. The angle between the plane of the six-membered ring and the planes of the carboxy groups attached to C3 and C6 is 3.3 (2) and 5.4 (2)°, respectively. The molecules form centrosymmetric dimers connected by two symmetry-related N—H···O═C hydrogen bonds (Table 1). The second H atom of the NH2 group is involved in an intramolecular N—H···O═C hydrogen bond. The crystal packing is shown in Figures 3 and 4. The molecules stack along the crystallographic a-direction. The interplanar distance in the stack is 3.396 (2) Å. Neighbouring stacks show a herringbone arrangement.

Related literature top

For studies on aminoterephthalic acid esters, see: Wegscheider et al. (1912); Clark et al. (1995); O'Connor et al. (1999); Lavalette et al. (2002); Jones et al. (2008). For syntheses wherein the title compound is used, see: Cordier & Coulet (1994); Metz & Weber (1999); Stengel-Rutkowski & Metz (2000); Jung et al. (2001); Herbst & Hunger (2004); Schweikart et al. (2007). For the crystal structure of the final product, Pigment Yellow 213, see: Schmidt et al. (2009).

Experimental top

The crystals of compound I were obtained from Clariant GmbH, Frankfurt am Main.

Refinement top

The H atoms attached to C atoms were geometrically positioned and were constrained using Cplanar—H = 0.95 Å, Cmethyl—H = 0.98 Å, Uiso(H) = 1.2Ueq(Cplanar) and Uiso(H) = 1.5Ueq(Cmethyl). The H atoms at the NH2 group were taken from a difference Fourier synthesis and were refined. The torsion angles about the O—Cmethyl groups were refined.

Computing details top

Data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT (Siemens, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top
[Figure 1] Fig. 1. Preparation of Pigment Yellow 213 in which compound (I) is used as preproduct.
[Figure 2] Fig. 2. Molecular structure of compound I, with atom labels and anisotropic displacement ellipsoids (drawn at 50% probability level) for non-H atoms.
[Figure 3] Fig. 3. Molecular packing of compound I showing the hydrogen bond architecture; view direction [100]. The hydrogen bonds are drawn as dashed lines.
[Figure 4] Fig. 4. Molecular packing of compound I, showing the herringbone arrangement of the molecules. View direction [001].
2-Aminoterephthalic acid dimethyl ester top
Crystal data top
C10H11NO4F(000) = 440
Mr = 209.20Dx = 1.456 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 57 reflections
a = 4.7721 (12) Åθ = 3–23°
b = 16.928 (5) ŵ = 0.11 mm−1
c = 11.841 (5) ÅT = 166 K
β = 93.88 (5)°Plate, colourless
V = 954.4 (6) Å30.75 × 0.32 × 0.04 mm
Z = 4
Data collection top
Siemens SMART 1K CCD
diffractometer		1687 independent reflections
Radiation source: normal-focus sealed tube884 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.140
ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		h = −5→5
Tmin = 0.760, Tmax = 0.995k = −20→20
11829 measured reflectionsl = −14→14
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)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 0.96 w = 1/[σ2(Fo2) + (0.06P)2]
where P = (Fo2 + 2Fc2)/3
1687 reflections(Δ/σ)max = 0.005
146 parametersΔρmax = 0.27 e Å−3
0 restraintsΔρmin = −0.24 e Å−3
Crystal data top
C10H11NO4V = 954.4 (6) Å3
Mr = 209.20Z = 4
Monoclinic, P21/cMo Kα radiation
a = 4.7721 (12) ŵ = 0.11 mm−1
b = 16.928 (5) ÅT = 166 K
c = 11.841 (5) Å0.75 × 0.32 × 0.04 mm
β = 93.88 (5)°
Data collection top
Siemens SMART 1K CCD
diffractometer		1687 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)		884 reflections with I > 2σ(I)
Tmin = 0.760, Tmax = 0.995Rint = 0.140
11829 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0540 restraints
wR(F2) = 0.134H atoms treated by a mixture of independent and constrained refinement
S = 0.96Δρmax = 0.27 e Å−3
1687 reflectionsΔρmin = −0.24 e Å−3
146 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
O1−0.2268 (4)0.60319 (11)0.30114 (17)0.0341 (6)
O2−0.1912 (5)0.58551 (12)0.11612 (18)0.0421 (7)
O30.7681 (5)0.32502 (11)0.44342 (17)0.0328 (6)
O40.8629 (4)0.29952 (12)0.26489 (18)0.0333 (6)
N10.5292 (7)0.36927 (18)0.0986 (3)0.0402 (8)
C10.4228 (7)0.40860 (18)0.1867 (3)0.0280 (8)
C20.2108 (7)0.46595 (17)0.1622 (3)0.0298 (8)
H2A0.14870.47620.08570.036*
C30.0944 (6)0.50678 (17)0.2471 (3)0.0258 (8)
C40.1783 (6)0.49355 (17)0.3592 (3)0.0287 (8)
H4A0.09670.52240.41750.034*
C50.3823 (6)0.43779 (17)0.3851 (2)0.0277 (8)
H5A0.44010.42810.46220.033*
C60.5072 (6)0.39497 (17)0.3004 (3)0.0263 (8)
C7−0.1217 (7)0.56897 (17)0.2121 (3)0.0281 (8)
C8−0.4282 (6)0.66622 (18)0.2753 (3)0.0386 (9)
H8A−0.32900.71340.25140.058*
H8B−0.52770.67850.34290.058*
H8C−0.56360.64920.21420.058*
C90.7296 (7)0.33575 (17)0.3320 (3)0.0267 (8)
C100.9869 (7)0.26942 (18)0.4801 (3)0.0381 (9)
H10A0.93940.21700.44950.057*
H10B1.00300.26700.56300.057*
H10C1.16610.28670.45270.057*
H1A0.702 (9)0.348 (2)0.120 (3)0.074 (14)*
H1B0.482 (7)0.385 (2)0.023 (3)0.059 (12)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0400 (15)0.0187 (12)0.0440 (14)0.0105 (11)0.0066 (11)0.0034 (10)
O20.0606 (18)0.0258 (14)0.0392 (15)0.0091 (12)−0.0009 (12)0.0034 (11)
O30.0391 (13)0.0174 (11)0.0416 (14)0.0065 (11)0.0000 (11)0.0041 (10)
O40.0396 (14)0.0177 (12)0.0431 (14)0.0031 (11)0.0068 (11)−0.0042 (10)
N10.049 (2)0.0357 (19)0.0361 (19)0.0125 (16)0.0027 (17)−0.0045 (15)
C10.032 (2)0.0169 (17)0.0351 (19)−0.0029 (16)0.0028 (16)−0.0014 (14)
C20.034 (2)0.0208 (18)0.0347 (19)−0.0019 (16)0.0017 (16)0.0027 (15)
C30.0273 (19)0.0148 (17)0.0354 (19)−0.0035 (15)0.0038 (15)0.0009 (14)
C40.037 (2)0.0129 (17)0.036 (2)−0.0012 (16)0.0058 (16)−0.0015 (14)
C50.035 (2)0.0139 (17)0.0334 (18)−0.0036 (15)−0.0004 (15)0.0010 (14)
C60.0305 (19)0.0109 (16)0.0376 (19)−0.0015 (14)0.0029 (16)−0.0005 (14)
C70.034 (2)0.0133 (18)0.037 (2)−0.0050 (15)0.0053 (17)0.0005 (16)
C80.040 (2)0.0197 (19)0.056 (2)0.0112 (16)−0.0004 (18)0.0031 (16)
C90.035 (2)0.0127 (17)0.0329 (19)−0.0090 (15)0.0039 (16)−0.0007 (14)
C100.041 (2)0.0234 (18)0.049 (2)0.0059 (17)−0.0031 (17)0.0051 (17)
Geometric parameters (Å, º) top
O1—C71.330 (3)C3—C41.379 (4)
O1—C81.455 (3)C3—C71.512 (4)
O2—C71.195 (3)C4—C51.376 (4)
O3—C91.333 (3)C4—H4A0.9500
O3—C101.450 (3)C5—C61.403 (4)
O4—C91.216 (3)C5—H5A0.9500
N1—C11.365 (4)C6—C91.489 (4)
N1—H1A0.92 (4)C8—H8A0.9800
N1—H1B0.94 (3)C8—H8B0.9800
C1—C61.398 (4)C8—H8C0.9800
C1—C21.418 (4)C10—H10A0.9800
C2—C31.368 (4)C10—H10B0.9800
C2—H2A0.9500C10—H10C0.9800
C7—O1—C8115.6 (2)C1—C6—C9120.5 (3)
C9—O3—C10115.7 (2)C5—C6—C9119.9 (3)
C1—N1—H1A111 (2)O2—C7—O1123.8 (3)
C1—N1—H1B120 (2)O2—C7—C3124.3 (3)
H1A—N1—H1B122 (3)O1—C7—C3111.9 (3)
N1—C1—C6123.9 (3)O1—C8—H8A109.5
N1—C1—C2118.4 (3)O1—C8—H8B109.5
C6—C1—C2117.7 (3)H8A—C8—H8B109.5
C3—C2—C1121.0 (3)O1—C8—H8C109.5
C3—C2—H2A119.5H8A—C8—H8C109.5
C1—C2—H2A119.5H8B—C8—H8C109.5
C2—C3—C4121.3 (3)O4—C9—O3122.3 (3)
C2—C3—C7117.0 (3)O4—C9—C6124.8 (3)
C4—C3—C7121.7 (3)O3—C9—C6112.9 (3)
C5—C4—C3118.7 (3)O3—C10—H10A109.5
C5—C4—H4A120.6O3—C10—H10B109.5
C3—C4—H4A120.6H10A—C10—H10B109.5
C4—C5—C6121.6 (3)O3—C10—H10C109.5
C4—C5—H5A119.2H10A—C10—H10C109.5
C6—C5—H5A119.2H10B—C10—H10C109.5
C1—C6—C5119.6 (3)
N1—C1—C2—C3179.4 (3)C8—O1—C7—O2−2.7 (4)
C6—C1—C2—C30.4 (4)C8—O1—C7—C3177.5 (2)
C1—C2—C3—C4−0.1 (4)C2—C3—C7—O2−1.7 (4)
C1—C2—C3—C7177.6 (3)C4—C3—C7—O2176.1 (3)
C2—C3—C4—C5−0.3 (4)C2—C3—C7—O1178.1 (2)
C7—C3—C4—C5−178.0 (3)C4—C3—C7—O1−4.1 (4)
C3—C4—C5—C60.5 (4)C10—O3—C9—O42.2 (4)
N1—C1—C6—C5−179.2 (3)C10—O3—C9—C6−178.6 (2)
C2—C1—C6—C5−0.1 (4)C1—C6—C9—O44.7 (4)
N1—C1—C6—C91.2 (5)C5—C6—C9—O4−175.0 (3)
C2—C1—C6—C9−179.8 (3)C1—C6—C9—O3−174.5 (3)
C4—C5—C6—C1−0.3 (4)C5—C6—C9—O35.8 (4)
C4—C5—C6—C9179.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O40.92 (4)2.01 (4)2.717 (4)133 (3)
N1—H1B···O2i0.95 (4)2.14 (3)3.016 (4)153 (3)
Symmetry code: (i) −x, −y+1, −z.

Experimental details

Crystal data
Chemical formulaC10H11NO4
Mr209.20
Crystal system, space groupMonoclinic, P21/c
Temperature (K)166
a, b, c (Å)4.7721 (12), 16.928 (5), 11.841 (5)
β (°) 93.88 (5)
V (Å3)954.4 (6)
Z4
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.75 × 0.32 × 0.04
Data collection
DiffractometerSiemens SMART 1K CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.760, 0.995
No. of measured, independent and
observed [I > 2σ(I)] reflections		11829, 1687, 884
Rint0.140
(sin θ/λ)max (Å−1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.134, 0.96
No. of reflections1687
No. of parameters146
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.27, −0.24

Computer programs: SMART (Siemens, 1995), SAINT (Siemens, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008), publCIF (Westrip, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1A···O40.92 (4)2.01 (4)2.717 (4)133 (3)
N1—H1B···O2i0.95 (4)2.14 (3)3.016 (4)153 (3)
Symmetry code: (i) −x, −y+1, −z.
 

Acknowledgements

The authors thank Clariant GmbH, Germany, for supplying the material and for financial support.

References

First citationBruker (2000). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationClark, A. S., Deans, B., Stevens, M. F. G., Tisdale, M. J., Wheelhouse, R. T., Denny, B. J. & Hartley, J. A. (1995). J. Med. Chem. 38, 1493–1504.  CrossRef CAS PubMed Web of Science Google Scholar
 First citationCordier, D. & Coulet, P. R. (1994). J. Chem Soc. Perkin Trans. 2, pp. 891–894.  CrossRef Google Scholar
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ISSN: 2056-9890
Volume 65| Part 10| October 2009| Pages o2468-o2469
doi:10.1107/S1600536809036095
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