4-Ethyl-amino-3-nitro-benzoic acid.

In the title compound, C(9)H(10)N(2)O(4), an intra-molecular N-H⋯O hydrogen-bond inter-action generates an S(6) ring motif. The nitro group is slightly twisted away from its attached benzene ring [dihedral angle = 15.29 (15)°]. In the crystal structure, mol-ecules are stacked down the a axis caused by short O⋯O(-1-x, -y, 2-z) contacts of 2.6481 (16) Å involving the O atoms of the nitro groups. The crystal packing is consolidated by inter-molecular O-H⋯O hydrogen bonds, linking the mol-ecules into centrosymmetric dimers.

Related literature

For reference bond lengths, see: Allen et al. (1987 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For information on the use of derivatives of nitro benzoic acid as precursors for heterocyclic compounds of biological inter­est, see: Ishida et al. (2006 ▶). For related structures, see: Mohd. Maidin et al. (2008 ▶); Narendra Babu et al. (2009 ▶). For the synthesis of ethyl 4-ethylamino-3-nitrobenzoate, see: Li et al. (2009 ▶).

Experimental

Crystal data

C9H10N2O4

M = 210.19

Triclinic,

a = 3.9354 (4) Å

b = 8.4741 (9) Å

c = 13.8106 (15) Å

α = 89.256 (5)°

β = 84.730 (4)°

γ = 82.304 (4)°

V = 454.49 (8) Å3

Z = 2

Mo Kα radiation

μ = 0.12 mm−1

T = 120 K

0.45 × 0.05 × 0.03 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (; Bruker, 2005 ▶) T min = 0.918, T max = 0.996

7604 measured reflections

2410 independent reflections

1903 reflections with I > 2σ(I)

R int = 0.023

Refinement

R[F 2 > 2σ(F 2)] = 0.041

wR(F 2) = 0.121

S = 1.06

2410 reflections

142 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.44 e Å−3

Δρmin = −0.33 e Å−3

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809014196/sj2618sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809014196/sj2618Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C9H10N2O4	Z = 2
Mr = 210.19	F(000) = 220
Triclinic, P1	Dx = 1.536 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 3.9354 (4) Å	Cell parameters from 3018 reflections
b = 8.4741 (9) Å	θ = 1.5–29.0°
c = 13.8106 (15) Å	µ = 0.12 mm−1
α = 89.256 (5)°	T = 120 K
β = 84.730 (4)°	Needle, yellow
γ = 82.304 (4)°	0.45 × 0.05 × 0.03 mm
V = 454.49 (8) Å3

Bruker SMART APEXII CCD area-detector diffractometer	2410 independent reflections
Radiation source: fine-focus sealed tube	1903 reflections with I > 2σ(I)
graphite	Rint = 0.023
φ and ω scans	θmax = 29.0°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −5→5
Tmin = 0.918, Tmax = 0.996	k = −11→11
7604 measured reflections	l = −18→18

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)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ2(Fo2) + (0.0647P)2 + 0.1132P] where P = (Fo2 + 2Fc2)/3
2410 reflections	(Δ/σ)max < 0.001
142 parameters	Δρmax = 0.44 e Å−3
0 restraints	Δρmin = −0.33 e Å−3

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat [Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105–107] operating at 120.0 (1) K.

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.

	x	y	z	Uiso*/Ueq
O1	−0.2816 (3)	0.09151 (12)	0.95790 (7)	0.0267 (3)
O2	0.0296 (3)	0.28327 (12)	0.93767 (7)	0.0260 (3)
O3	0.3986 (3)	0.31078 (13)	0.49289 (7)	0.0302 (3)
O4	0.3740 (3)	0.47173 (12)	0.62170 (8)	0.0272 (3)
H1O4	0.4493	0.5304	0.5797	0.041*
N1	−0.0961 (3)	0.17166 (13)	0.90601 (8)	0.0175 (2)
N2	−0.2305 (3)	−0.12944 (13)	0.82002 (8)	0.0174 (2)
C1	0.1130 (3)	0.24569 (15)	0.74460 (9)	0.0164 (3)
H1A	0.1501	0.3413	0.7714	0.020*
C2	−0.0252 (3)	0.13158 (15)	0.80371 (9)	0.0155 (3)
C3	−0.0921 (3)	−0.01649 (14)	0.76646 (9)	0.0152 (3)
C4	0.0068 (3)	−0.04224 (15)	0.66528 (9)	0.0179 (3)
H4A	−0.0235	−0.1381	0.6374	0.021*
C5	0.1453 (4)	0.07084 (16)	0.60827 (9)	0.0186 (3)
H5A	0.2077	0.0496	0.5427	0.022*
C6	0.1956 (3)	0.21795 (15)	0.64634 (9)	0.0175 (3)
C7	0.3311 (4)	0.34040 (16)	0.58304 (10)	0.0194 (3)
C8	−0.2853 (4)	−0.28286 (15)	0.78103 (10)	0.0177 (3)
H8A	−0.0688	−0.3375	0.7516	0.021*
H8B	−0.4447	−0.2657	0.7312	0.021*
C9	−0.4293 (4)	−0.38448 (16)	0.86180 (10)	0.0206 (3)
H9A	−0.4684	−0.4841	0.8355	0.031*
H9B	−0.6428	−0.3299	0.8910	0.031*
H9C	−0.2680	−0.4038	0.9101	0.031*
H1N2	−0.299 (5)	−0.109 (2)	0.8778 (14)	0.030 (5)*

	U11	U22	U33	U12	U13	U23
O1	0.0407 (6)	0.0221 (5)	0.0181 (5)	−0.0142 (4)	0.0083 (4)	−0.0012 (4)
O2	0.0395 (6)	0.0233 (5)	0.0178 (5)	−0.0145 (4)	−0.0011 (4)	−0.0033 (4)
O3	0.0478 (7)	0.0288 (6)	0.0155 (5)	−0.0165 (5)	0.0056 (4)	0.0006 (4)
O4	0.0415 (7)	0.0199 (5)	0.0215 (5)	−0.0142 (4)	0.0048 (4)	0.0009 (4)
N1	0.0222 (6)	0.0146 (5)	0.0155 (5)	−0.0032 (4)	−0.0002 (4)	0.0006 (4)
N2	0.0236 (6)	0.0144 (5)	0.0147 (5)	−0.0057 (4)	0.0004 (4)	0.0001 (4)
C1	0.0179 (6)	0.0142 (6)	0.0176 (6)	−0.0044 (5)	−0.0013 (5)	0.0004 (5)
C2	0.0181 (6)	0.0151 (6)	0.0133 (6)	−0.0025 (5)	−0.0007 (5)	0.0002 (4)
C3	0.0150 (6)	0.0142 (6)	0.0165 (6)	−0.0018 (5)	−0.0023 (5)	0.0011 (5)
C4	0.0215 (7)	0.0165 (6)	0.0162 (6)	−0.0047 (5)	−0.0016 (5)	−0.0022 (5)
C5	0.0215 (7)	0.0204 (6)	0.0143 (6)	−0.0056 (5)	0.0007 (5)	−0.0008 (5)
C6	0.0196 (7)	0.0166 (6)	0.0166 (6)	−0.0050 (5)	0.0002 (5)	0.0014 (5)
C7	0.0232 (7)	0.0192 (6)	0.0166 (6)	−0.0070 (5)	0.0007 (5)	0.0013 (5)
C8	0.0211 (7)	0.0147 (6)	0.0179 (6)	−0.0051 (5)	−0.0016 (5)	−0.0010 (5)
C9	0.0246 (7)	0.0164 (6)	0.0218 (7)	−0.0071 (5)	−0.0016 (5)	0.0007 (5)

O1—N1	1.2375 (14)	C3—C4	1.4273 (18)
O2—N1	1.2273 (14)	C4—C5	1.3700 (18)
O3—C7	1.2700 (17)	C4—H4A	0.9300
O4—C7	1.2784 (16)	C5—C6	1.4043 (18)
O4—H1O4	0.8200	C5—H5A	0.9300
N1—C2	1.4506 (16)	C6—C7	1.4711 (18)
N2—C3	1.3441 (16)	C8—C9	1.5155 (18)
N2—C8	1.4634 (16)	C8—H8A	0.9700
N2—H1N2	0.832 (19)	C8—H8B	0.9700
C1—C6	1.3818 (18)	C9—H9A	0.9600
C1—C2	1.3914 (17)	C9—H9B	0.9600
C1—H1A	0.9300	C9—H9C	0.9600
C2—C3	1.4278 (17)
C7—O4—H1O4	109.5	C4—C5—H5A	119.2
O2—N1—O1	122.64 (11)	C6—C5—H5A	119.2
O2—N1—C2	118.90 (11)	C1—C6—C5	118.53 (12)
O1—N1—C2	118.46 (10)	C1—C6—C7	120.64 (12)
C3—N2—C8	123.74 (11)	C5—C6—C7	120.83 (12)
C3—N2—H1N2	117.9 (13)	O3—C7—O4	123.29 (12)
C8—N2—H1N2	118.3 (13)	O3—C7—C6	118.53 (12)
C6—C1—C2	120.49 (12)	O4—C7—C6	118.18 (12)
C6—C1—H1A	119.8	N2—C8—C9	109.98 (11)
C2—C1—H1A	119.8	N2—C8—H8A	109.7
C1—C2—C3	122.29 (11)	C9—C8—H8A	109.7
C1—C2—N1	115.93 (11)	N2—C8—H8B	109.7
C3—C2—N1	121.78 (11)	C9—C8—H8B	109.7
N2—C3—C4	120.00 (11)	H8A—C8—H8B	108.2
N2—C3—C2	124.66 (12)	C8—C9—H9A	109.5
C4—C3—C2	115.33 (11)	C8—C9—H9B	109.5
C5—C4—C3	121.59 (12)	H9A—C9—H9B	109.5
C5—C4—H4A	119.2	C8—C9—H9C	109.5
C3—C4—H4A	119.2	H9A—C9—H9C	109.5
C4—C5—C6	121.69 (12)	H9B—C9—H9C	109.5
C6—C1—C2—C3	−0.9 (2)	N2—C3—C4—C5	179.34 (13)
C6—C1—C2—N1	178.84 (11)	C2—C3—C4—C5	−2.10 (19)
O2—N1—C2—C1	−14.67 (18)	C3—C4—C5—C6	−0.3 (2)
O1—N1—C2—C1	165.34 (12)	C2—C1—C6—C5	−1.6 (2)
O2—N1—C2—C3	165.04 (12)	C2—C1—C6—C7	177.98 (12)
O1—N1—C2—C3	−14.95 (19)	C4—C5—C6—C1	2.2 (2)
C8—N2—C3—C4	0.74 (19)	C4—C5—C6—C7	−177.39 (13)
C8—N2—C3—C2	−177.68 (12)	C1—C6—C7—O3	−178.93 (12)
C1—C2—C3—N2	−178.83 (12)	C5—C6—C7—O3	0.7 (2)
N1—C2—C3—N2	1.5 (2)	C1—C6—C7—O4	0.9 (2)
C1—C2—C3—C4	2.69 (19)	C5—C6—C7—O4	−179.51 (13)
N1—C2—C3—C4	−177.01 (11)	C3—N2—C8—C9	177.29 (12)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H1O4···O3i	0.82	1.80	2.6092 (15)	168
N2—H1N2···O1	0.831 (19)	2.052 (18)	2.6634 (15)	130.0 (16)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O4—H1O4⋯O3i	0.82	1.80	2.6092 (15)	168
N2—H1N2⋯O1	0.831 (19)	2.052 (18)	2.6634 (15)	130.0 (16)

Symmetry code: (i) .