Ethyl 4-fluoro-3-nitro­benzoate

Abstract

In the title compound, C₉H₈FNO₄, C—H⋯O inter­molecular inter­actions form dimers with R ² ₂(10) motifs. These dimers are arranged into chains parallel to the b axis and the chains are stacked down the c axis.

Related literature

For general background, see: Ishida et al. (2006 ▶); Rida et al. (2005 ▶); Mohd. Maidin, Abdul Rahim, Abdul Hamid et al. (2008 ▶). For bond-length data, see: Allen et al. (1987 ▶). For related structures, see: Mohd. Maidin, Abdul Rahim, Osman et al. (2008 ▶); Li et al. (2008 ▶, 2009 ▶). For details of hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For details on the stability of the temperature controller, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

• C₉H₈FNO₄

• M _r = 213.16

• Monoclinic,

• a = 9.9246 (3) Å

• b = 13.2883 (3) Å

• c = 6.9310 (2) Å

• β = 94.410 (2)°

• V = 911.36 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 0.14 mm⁻¹

• T = 100 K

• 0.55 × 0.22 × 0.09 mm

Data collection

• Bruker SMART APEXII CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.929, T _max = 0.988

• 12540 measured reflections

• 2913 independent reflections

• 2411 reflections with I > 2σ(I)

• R _int = 0.028

Refinement

• R[F ² > 2σ(F ²)] = 0.045

• wR(F ²) = 0.139

• S = 1.11

• 2913 reflections

• 138 parameters

• H-atom parameters constrained

• Δρ_max = 0.55 e Å⁻³

• Δρ_min = −0.36 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 ▶).

Supplementary Material

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

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O4i	0.93	2.44	3.2380 (15)	144

Symmetry code: (i) .

supplementary crystallographic information

Comment

The nitro benzoic acid intermediates are convenient starting materials for the synthesis of various biologically active heterocycles e.g. benzimidazoles (Ishida et al., 2006) and benzoxazoles (Rida et al., 2005). As a part of our ongoing studies on new nitro benzoic acid derivatives (Mohd. Maidin, Abdul Rahim, Abdul Hamid et al., 2008), we have synthesized the title compound as an intermediate and report its structure here.

The bond lengths (Allen et al., 1987) and angles observed in (I) are within normal ranges and are consistent with other related structures (Mohd. Maidin, Abdul Rahim, Osman et al., 2008; Li et al., 2009; Li et al., 2008). The C1—H1A···O4ⁱ intermolecular interactions (Table 2) linked the molecules into dimers forming 10-membered rings with R²₂(10) motifs (Bernstein et al., 1995). In the crystal structure, these dimers are arranged into chains parallel to the b axis. The chains are stacked down the c axis (Fig. 2).

Experimental

For the preparation of the title compound, 4-fluoro-3-nitro-benzoic acid (5.0 g, 0.027 mol) was refluxed in absolute ethanol (50 ml) and conc. H₂SO₄ (2.0 ml) for 8 h. Upon reaction completion, ethanol was evaporated and the reaction mixture was diluted with water. The aqueous layer was extracted with ethyl acetate (25 x 2 ml). The combined organic layer was collected and dried over anhydrous MgSO₄. The solvent was removed under reduced pressure to afford yellow oil as the crude product. Recrystallization with hot ethyl acetate and petroleum ether (60–80) yielded colourless crystals that were found suitable for X-ray analysis.

Refinement

All the H atoms were positioned geometrically and refined using a riding model with C—H = 0.93Å for aromatic and 0.96Å for CH₃. The U_iso values were constrained to be -1.5U_eq of the carrier atom for the methyl H atoms and -1.2U_equ for the remaining hydrogen atoms. The rotating model group was considered for the methyl group.

Figures

Fig. 1.

The asymmetric unit of the title compound, showing 50% probability displacement ellipsoids and the atom numbering scheme.

Fig. 2.

The crystal packing of the title compound, viewed down the c axis. Intermolecular hydrogen bondings are shown as dotted lines.

Crystal data

C9H8FNO4	F(000) = 440
Mr = 213.16	Dx = 1.554 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 5027 reflections
a = 9.9246 (3) Å	θ = 2.6–30.8°
b = 13.2883 (3) Å	µ = 0.14 mm−1
c = 6.9310 (2) Å	T = 100 K
β = 94.410 (2)°	Block, colourless
V = 911.36 (4) Å3	0.55 × 0.22 × 0.09 mm
Z = 4

Data collection

Bruker SMART APEXII CCD area-detector diffractometer	2913 independent reflections
Radiation source: sealed tube	2411 reflections with I > 2σ(I)
graphite	Rint = 0.028
φ and ω scans	θmax = 31.1°, θmin = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −14→14
Tmin = 0.929, Tmax = 0.988	k = −18→19
12540 measured reflections	l = −10→10

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045	H-atom parameters constrained
wR(F2) = 0.139	w = 1/[σ2(Fo2) + (0.0772P)2 + 0.1955P] where P = (Fo2 + 2Fc2)/3
S = 1.11	(Δ/σ)max < 0.001
2913 reflections	Δρmax = 0.55 e Å−3
138 parameters	Δρmin = −0.36 e Å−3
0 restraints	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.018 (4)

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
F1	0.04351 (7)	0.10679 (6)	0.18019 (12)	0.0241 (2)
O1	0.07165 (9)	0.29746 (7)	0.29028 (14)	0.0240 (2)
O2	−0.04092 (9)	0.39394 (6)	0.08249 (15)	0.0247 (2)
O3	−0.52330 (8)	0.30897 (6)	−0.00372 (14)	0.0203 (2)
O4	−0.58597 (9)	0.14638 (7)	−0.02358 (16)	0.0276 (2)
N1	−0.02296 (10)	0.31401 (7)	0.16902 (15)	0.0172 (2)
C1	−0.31523 (12)	0.08546 (9)	0.06256 (18)	0.0197 (2)
H1A	−0.3804	0.0356	0.0410	0.024*
C2	−0.18146 (12)	0.05833 (9)	0.10726 (19)	0.0211 (3)
H2A	−0.1566	−0.0091	0.1139	0.025*
C3	−0.08581 (11)	0.13301 (9)	0.14173 (17)	0.0181 (2)
C4	−0.12280 (11)	0.23409 (8)	0.12960 (16)	0.0154 (2)
C5	−0.25648 (11)	0.26145 (8)	0.08154 (16)	0.0154 (2)
H5A	−0.2807	0.3290	0.0710	0.018*
C6	−0.35338 (11)	0.18648 (8)	0.04945 (17)	0.0161 (2)
C7	−0.49936 (11)	0.21032 (9)	0.00323 (18)	0.0179 (2)
C8	−0.66549 (12)	0.33789 (10)	−0.0398 (2)	0.0231 (3)
H8A	−0.7170	0.3145	0.0648	0.028*
H8B	−0.7035	0.3081	−0.1597	0.028*
C9	−0.67127 (13)	0.45039 (10)	−0.0529 (2)	0.0280 (3)
H9A	−0.7638	0.4716	−0.0713	0.042*
H9B	−0.6233	0.4725	−0.1603	0.042*
H9C	−0.6304	0.4791	0.0646	0.042*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
F1	0.0168 (3)	0.0239 (4)	0.0312 (4)	0.0077 (3)	0.0003 (3)	0.0020 (3)
O1	0.0153 (4)	0.0295 (5)	0.0264 (5)	0.0006 (3)	−0.0037 (3)	0.0008 (4)
O2	0.0228 (4)	0.0174 (4)	0.0333 (5)	−0.0018 (3)	−0.0025 (4)	0.0042 (4)
O3	0.0123 (4)	0.0155 (4)	0.0324 (5)	0.0009 (3)	−0.0017 (3)	0.0002 (3)
O4	0.0191 (4)	0.0176 (4)	0.0453 (6)	−0.0038 (3)	−0.0041 (4)	0.0012 (4)
N1	0.0141 (4)	0.0180 (5)	0.0196 (5)	0.0007 (3)	0.0017 (3)	−0.0015 (4)
C1	0.0201 (5)	0.0148 (5)	0.0242 (6)	−0.0008 (4)	0.0010 (4)	−0.0002 (4)
C2	0.0229 (6)	0.0140 (5)	0.0263 (6)	0.0037 (4)	0.0015 (5)	0.0004 (4)
C3	0.0166 (5)	0.0185 (5)	0.0192 (5)	0.0049 (4)	0.0015 (4)	0.0006 (4)
C4	0.0144 (5)	0.0158 (5)	0.0159 (5)	0.0007 (4)	0.0010 (4)	0.0001 (4)
C5	0.0144 (5)	0.0149 (5)	0.0169 (5)	0.0018 (4)	0.0014 (4)	0.0005 (4)
C6	0.0148 (5)	0.0152 (5)	0.0181 (5)	0.0005 (4)	0.0004 (4)	−0.0001 (4)
C7	0.0157 (5)	0.0162 (5)	0.0216 (5)	−0.0003 (4)	0.0005 (4)	0.0003 (4)
C8	0.0119 (5)	0.0218 (6)	0.0350 (7)	0.0007 (4)	−0.0013 (4)	0.0022 (5)
C9	0.0188 (6)	0.0213 (6)	0.0426 (8)	0.0040 (4)	−0.0050 (5)	−0.0051 (5)

Geometric parameters (Å, °)

F1—C3	1.3368 (13)	C3—C4	1.3932 (16)
O1—N1	1.2308 (13)	C4—C5	1.3912 (14)
O2—N1	1.2261 (13)	C5—C6	1.3906 (15)
O3—C7	1.3326 (14)	C5—H5A	0.9300
O3—C8	1.4653 (13)	C6—C7	1.4935 (15)
O4—C7	1.2127 (14)	C8—C9	1.4984 (19)
N1—C4	1.4638 (15)	C8—H8A	0.9700
C1—C2	1.3876 (16)	C8—H8B	0.9700
C1—C6	1.3959 (16)	C9—H9A	0.9600
C1—H1A	0.9300	C9—H9B	0.9600
C2—C3	1.3814 (17)	C9—H9C	0.9600
C2—H2A	0.9300
C7—O3—C8	115.52 (9)	C5—C6—C1	119.85 (10)
O2—N1—O1	124.29 (10)	C5—C6—C7	122.00 (10)
O2—N1—C4	117.80 (9)	C1—C6—C7	118.14 (10)
O1—N1—C4	117.89 (10)	O4—C7—O3	124.15 (11)
C2—C1—C6	120.96 (11)	O4—C7—C6	123.28 (11)
C2—C1—H1A	119.5	O3—C7—C6	112.57 (9)
C6—C1—H1A	119.5	O3—C8—C9	107.69 (9)
C3—C2—C1	119.01 (11)	O3—C8—H8A	110.2
C3—C2—H2A	120.5	C9—C8—H8A	110.2
C1—C2—H2A	120.5	O3—C8—H8B	110.2
F1—C3—C2	118.93 (10)	C9—C8—H8B	110.2
F1—C3—C4	120.52 (10)	H8A—C8—H8B	108.5
C2—C3—C4	120.51 (10)	C8—C9—H9A	109.5
C5—C4—C3	120.56 (10)	C8—C9—H9B	109.5
C5—C4—N1	118.32 (10)	H9A—C9—H9B	109.5
C3—C4—N1	121.11 (10)	C8—C9—H9C	109.5
C6—C5—C4	119.08 (10)	H9A—C9—H9C	109.5
C6—C5—H5A	120.5	H9B—C9—H9C	109.5
C4—C5—H5A	120.5
C6—C1—C2—C3	0.93 (19)	N1—C4—C5—C6	−178.04 (10)
C1—C2—C3—F1	−178.41 (11)	C4—C5—C6—C1	−1.07 (18)
C1—C2—C3—C4	−0.74 (19)	C4—C5—C6—C7	178.12 (10)
F1—C3—C4—C5	177.27 (10)	C2—C1—C6—C5	−0.02 (19)
C2—C3—C4—C5	−0.36 (18)	C2—C1—C6—C7	−179.25 (11)
F1—C3—C4—N1	−3.44 (17)	C8—O3—C7—O4	2.20 (18)
C2—C3—C4—N1	178.93 (11)	C8—O3—C7—C6	−177.35 (10)
O2—N1—C4—C5	−31.36 (16)	C5—C6—C7—O4	−179.29 (12)
O1—N1—C4—C5	146.88 (11)	C1—C6—C7—O4	−0.09 (19)
O2—N1—C4—C3	149.33 (12)	C5—C6—C7—O3	0.26 (16)
O1—N1—C4—C3	−32.42 (16)	C1—C6—C7—O3	179.47 (11)
C3—C4—C5—C6	1.27 (17)	C7—O3—C8—C9	−177.07 (11)

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1A···O4i	0.93	2.44	3.2380 (15)	144

Symmetry codes: (i) −x−1, −y, −z.