Ethyl 3-methyl-5-nitro-1H-imidazole-2-carboxyl­ate

The title compound, C₇H₉N₃O₄, exists as a planar mol­ecule whose carboxy­ethyl fragment is disordered across a crystallographic mirror plane. The fragment is twisted by 15.1 (1)° with respect to the plane.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.038
• wR factor = 0.124
• Data-to-parameter ratio = 11.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT301_ALERT_3_C Main Residue  Disorder .........................      22.00 Perc.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97.

Ethyl 3-methyl-5-nitro-1H-imidazole-2-carboxylate

Crystal data

C7H9N3O4	F(000) = 416
Mr = 199.17	Dx = 1.455 Mg m^−3
Orthorhombic, Pnma	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2n	Cell parameters from 861 reflections
a = 8.940 (1) Å	θ = 2.7–27.1°
b = 6.768 (1) Å	µ = 0.12 mm^−1
c = 15.028 (2) Å	T = 298 K
V = 909.2 (2) Å^3	Block, colorless
Z = 4	0.50 × 0.33 × 0.21 mm

Data collection

Bruker SMART area-detector diffractometer	954 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.017
Graphite monochromator	θmax = 27.1°, θmin = 2.7°
φ and ω scans	h = −10→11
11054 measured reflections	k = −7→8
1089 independent reflections	l = −19→19

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.124	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0803P)^2 + 0.1466P] where P = (Fo^2 + 2Fc^2)/3
1089 reflections	(Δ/σ)max < 0.001
99 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.16 e Å^−3

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
O1	0.5077 (2)	0.1981 (2)	0.6789 (1)	0.0518 (6)	0.50
O2	0.2765 (2)	0.279 (2)	0.6250 (1)	0.064 (2)	0.50
O3	0.7800 (2)	0.2500	0.2994 (1)	0.0646 (4)
O4	0.8913 (2)	0.2500	0.4257 (1)	0.0856 (6)
N1	0.6255 (2)	0.2500	0.5130 (1)	0.0426 (4)
N2	0.4010 (2)	0.2500	0.4492 (1)	0.0420 (3)
N3	0.7798 (2)	0.2500	0.3808 (1)	0.0517 (4)
C1	0.4506 (4)	0.1661 (4)	0.7683 (2)	0.0559 (6)	0.50
C2	0.4181 (4)	0.3511 (5)	0.8151 (2)	0.0691 (8)	0.50
C3	0.4082 (2)	0.2500	0.6150 (1)	0.0541 (5)
C4	0.2380 (2)	0.2500	0.4370 (2)	0.0613 (5)
C5	0.4806 (2)	0.2500	0.5269 (1)	0.0396 (4)
C6	0.5012 (2)	0.2500	0.3827 (1)	0.0450 (4)
C7	0.6370 (2)	0.2500	0.4239 (1)	0.0412 (4)
H1a	0.5236	0.0915	0.8022	0.067*	0.50
H1b	0.3599	0.0878	0.7650	0.067*	0.50
H2a	0.3956	0.3232	0.8763	0.104*	0.50
H2b	0.3338	0.4147	0.7877	0.104*	0.50
H2c	0.5036	0.4366	0.8119	0.104*	0.50
H4a	0.2146	0.2852	0.3767	0.092*	0.50
H4b	0.1935	0.3442	0.4768	0.092*	0.50
H4c	0.1993	0.1207	0.4496	0.092*	0.50
H6	0.4821	0.2500	0.3218	0.054*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.053 (1)	0.070 (2)	0.033 (1)	0.003 (1)	−0.001 (1)	−0.002 (1)
O2	0.043 (1)	0.099 (7)	0.050 (1)	0.004 (1)	0.009 (1)	−0.004 (1)
O3	0.063 (1)	0.086 (1)	0.044 (1)	0.000	0.016 (1)	0.000
O4	0.037 (1)	0.152 (2)	0.067 (1)	0.000	0.001 (1)	0.000
N1	0.037 (1)	0.054 (1)	0.037 (1)	0.000	−0.001 (1)	0.000
N2	0.035 (1)	0.052 (1)	0.039 (1)	0.000	−0.003 (1)	0.000
N3	0.041 (1)	0.066 (1)	0.048 (1)	0.000	0.007 (1)	0.000
C1	0.067 (2)	0.064 (1)	0.037 (1)	−0.001 (1)	0.002 (1)	0.005 (1)
C2	0.079 (2)	0.081 (2)	0.048 (2)	0.004 (2)	0.007 (2)	−0.009 (2)
C3	0.042 (1)	0.081 (1)	0.040 (1)	0.000	0.002 (1)	0.000
C4	0.035 (1)	0.095 (2)	0.054 (1)	0.000	−0.009 (1)	0.000
C5	0.037 (1)	0.047 (1)	0.035 (1)	0.000	−0.001 (1)	0.000
C6	0.045 (1)	0.055 (1)	0.035 (1)	0.000	−0.002 (1)	0.000
C7	0.038 (1)	0.049 (1)	0.037 (1)	0.000	0.003 (1)	0.000

Geometric parameters (Å, º)

O1—C1	1.453 (3)	C3—C5	1.475 (2)
O1—C3	1.355 (2)	C6—C7	1.363 (2)
O2—C3	1.203 (4)	C1—H1a	0.97
O3—N3	1.223 (2)	C1—H1b	0.97
O4—N3	1.203 (2)	C2—H2a	0.96
N1—C5	1.312 (2)	C2—H2b	0.96
N1—C7	1.343 (2)	C2—H2c	0.96
N2—C4	1.469 (2)	C4—H4a	0.96
N2—C6	1.342 (2)	C4—H4b	0.96
N2—C5	1.367 (2)	C4—H4c	0.96
N3—C7	1.432 (2)	C6—H6	0.93
C1—C2	1.464 (4)
C1—O1—C3	117.6 (2)	N1—C7—C6	112.7 (1)
C5—N1—C7	103.5 (1)	N1—C7—N3	121.3 (1)
C4—N2—C5	128.5 (2)	N3—C7—C6	126.1 (2)
C4—N2—C6	124.7 (2)	O1—C1—H1a	109.1
C5—N2—C6	106.8 (1)	C2—C1—H1a	109.1
O4—N3—O3	124.1 (2)	O1—C1—H1b	109.1
O3—N3—C7	117.0 (2)	C2—C1—H1b	109.1
O4—N3—C7	119.0 (2)	H1a—C1—H1b	107.8
O1—C1—C2	112.7 (2)	N2—C4—H4a	109.5
O2—C3—O1	126.6 (2)	N2—C4—H4b	109.5
O1—C3—C5	110.4 (2)	H4a—C4—H4b	109.5
O2—C3—C5	122.8 (2)	N2—C4—H4c	109.5
N1—C5—N2	112.2 (1)	H4a—C4—H4c	109.5
N1—C5—C3	125.2 (2)	H4b—C4—H4c	109.5
N2—C5—C3	122.6 (2)	N2—C6—H6	127.6
N2—C6—C7	104.8 (1)	C7—C6—H6	127.6
C3—O1—C1—C2	−76.5 (3)	O2^i—C3—C5—N2	11.2 (8)
C1—O1—C3—O2^i	−18.9 (7)	O2—C3—C5—N2	−11.2 (8)
C1—O1—C3—O2	2.5 (8)	O1—C3—C5—N2	163.9 (1)
C1—O1—C3—O1^i	91.9 (2)	O1^i—C3—C5—N2	−163.9 (1)
C1—O1—C3—C5	−172.4 (2)	C5—N2—C6—C7	0.0
C7—N1—C5—N2	0.0	C4—N2—C6—C7	180.0
C7—N1—C5—C3	180.0	C5—N1—C7—C6	0.0
C6—N2—C5—N1	0.0	C5—N1—C7—N3	180.0
C4—N2—C5—N1	180.0	N2—C6—C7—N1	0.0
C6—N2—C5—C3	180.0	N2—C6—C7—N3	180.0
C4—N2—C5—C3	0.0	O4—N3—C7—N1	0.0
O2^i—C3—C5—N1	−168.8 (8)	O3—N3—C7—N1	180.0
O2—C3—C5—N1	168.8 (8)	O4—N3—C7—C6	180.0
O1—C3—C5—N1	−16.1 (1)	O3—N3—C7—C6	0.0
O1^i—C3—C5—N1	16.1 (1)

Symmetry code: (i) x, −y+1/2, z.