N,N′-Bis(4-nitro­phen­yl)oxamide

The mol­ecule of the title compound, C₁₄H₁₀N₄O₆, lies on a crystallographically imposed center of symmetry at the mid-point of the C—C bond of the oxamide unit. Mol­ecules are linked into zigzag chains by N—H...O hydrogen bonds. The packing is further stabilized by van der Waals forces.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.048
• wR factor = 0.120
• Data-to-parameter ratio = 12.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT369_ALERT_2_C Long   C(sp2)-C(sp2) Bond  C7     -   C7_a   ...       1.54 Ang.

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 2003).

N,N'-Bis(4-nitrophenyl)oxalamide

Crystal data

C14H10N4O6	F(000) = 340
Mr = 330.26	Dx = 1.579 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 3.7185 (8) Å	Cell parameters from 794 reflections
b = 13.942 (3) Å	θ = 2.9–24.7°
c = 13.571 (3) Å	µ = 0.13 mm^−1
β = 99.059 (6)°	T = 293 K
V = 694.8 (3) Å^3	Needle, colourless
Z = 2	0.50 × 0.08 × 0.06 mm

Data collection

Siemens SMART 1000 CCD area-detector diffractometer	1370 independent reflections
Radiation source: fine-focus sealed tube	1001 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.031
Detector resolution: 8.33 pixels mm^-1	θmax = 26.0°, θmin = 2.1°
ω scans	h = −4→4
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −12→17
Tmin = 0.939, Tmax = 0.992	l = −16→16
3825 measured reflections

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.120	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0562P)^2 + 0.0313P] where P = (Fo^2 + 2Fc^2)/3
1370 reflections	(Δ/σ)max < 0.001
114 parameters	Δρmax = 0.24 e Å^−3
0 restraints	Δρmin = −0.19 e Å^−3

Special details

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
O1	−0.3471 (4)	−0.12462 (12)	−0.55005 (11)	0.0538 (5)
O2	−0.0265 (4)	−0.25422 (12)	−0.53195 (11)	0.0507 (5)
O3	0.2323 (5)	0.07470 (12)	−0.08431 (11)	0.0606 (5)
N1	−0.1298 (5)	−0.17827 (13)	−0.49971 (12)	0.0372 (5)
N2	0.4290 (5)	−0.07814 (12)	−0.10492 (12)	0.0354 (5)
H2A	0.5556	−0.1229	−0.0726	0.050 (7)*
C1	0.3343 (5)	−0.19258 (14)	−0.23766 (15)	0.0334 (5)
H1A	0.4597	−0.2372	−0.1942	0.039 (6)*
C2	0.2030 (5)	−0.21848 (15)	−0.33440 (14)	0.0337 (5)
H2B	0.2405	−0.2800	−0.3573	0.041 (6)*
C3	0.0135 (5)	−0.15098 (14)	−0.39701 (14)	0.0300 (5)
C4	−0.0466 (5)	−0.05960 (15)	−0.36570 (14)	0.0336 (5)
H4A	−0.1770	−0.0159	−0.4093	0.036 (6)*
C5	0.0890 (5)	−0.03310 (15)	−0.26888 (14)	0.0349 (5)
H5A	0.0531	0.0288	−0.2469	0.052 (7)*
C6	0.2800 (5)	−0.09995 (14)	−0.20447 (14)	0.0303 (5)
C7	0.3987 (6)	0.00299 (15)	−0.05385 (15)	0.0363 (5)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0636 (11)	0.0567 (11)	0.0341 (9)	0.0016 (9)	−0.0137 (8)	0.0030 (8)
O2	0.0693 (12)	0.0446 (10)	0.0362 (9)	−0.0031 (8)	0.0022 (8)	−0.0117 (7)
O3	0.0902 (13)	0.0473 (10)	0.0365 (9)	0.0273 (9)	−0.0141 (8)	−0.0099 (8)
N1	0.0441 (11)	0.0386 (11)	0.0278 (10)	−0.0094 (9)	0.0026 (8)	0.0000 (8)
N2	0.0466 (11)	0.0320 (10)	0.0250 (9)	0.0049 (8)	−0.0027 (8)	−0.0012 (8)
C1	0.0393 (12)	0.0323 (12)	0.0271 (11)	0.0027 (9)	0.0007 (8)	0.0018 (9)
C2	0.0410 (12)	0.0288 (11)	0.0310 (11)	−0.0026 (9)	0.0044 (9)	−0.0042 (9)
C3	0.0324 (11)	0.0356 (12)	0.0214 (10)	−0.0071 (9)	0.0022 (8)	−0.0018 (9)
C4	0.0374 (12)	0.0353 (12)	0.0267 (11)	0.0013 (9)	0.0007 (9)	0.0054 (9)
C5	0.0416 (12)	0.0324 (12)	0.0293 (12)	0.0013 (9)	0.0015 (9)	−0.0006 (9)
C6	0.0321 (11)	0.0335 (12)	0.0249 (10)	−0.0029 (8)	0.0031 (8)	−0.0014 (9)
C7	0.0436 (13)	0.0352 (13)	0.0287 (12)	0.0033 (9)	0.0011 (9)	−0.0028 (9)

Geometric parameters (Å, º)

O1—N1	1.227 (2)	C1—H1A	0.9300
O2—N1	1.230 (2)	C2—C3	1.384 (3)
O3—C7	1.214 (2)	C2—H2B	0.9300
N1—C3	1.462 (2)	C3—C4	1.372 (3)
N2—C7	1.341 (3)	C4—C5	1.381 (3)
N2—C6	1.410 (2)	C4—H4A	0.9299
N2—H2A	0.8600	C5—C6	1.393 (3)
C1—C2	1.375 (3)	C5—H5A	0.9300
C1—C6	1.393 (3)	C7—C7^i	1.538 (4)
O1—N1—O2	122.81 (17)	C2—C3—N1	118.83 (18)
O1—N1—C3	118.78 (18)	C3—C4—C5	119.33 (19)
O2—N1—C3	118.41 (17)	C3—C4—H4A	120.3
C7—N2—C6	128.68 (18)	C5—C4—H4A	120.4
C7—N2—H2A	115.6	C4—C5—C6	119.4 (2)
C6—N2—H2A	115.7	C4—C5—H5A	120.3
C2—C1—C6	120.29 (19)	C6—C5—H5A	120.3
C2—C1—H1A	119.8	C1—C6—C5	120.19 (18)
C6—C1—H1A	119.9	C1—C6—N2	117.04 (17)
C1—C2—C3	118.5 (2)	C5—C6—N2	122.77 (18)
C1—C2—H2B	120.8	O3—C7—N2	126.79 (19)
C3—C2—H2B	120.7	O3—C7—C7^i	121.0 (2)
C4—C3—C2	122.22 (18)	N2—C7—C7^i	112.2 (2)
C4—C3—N1	118.95 (17)
C6—C1—C2—C3	−0.7 (3)	C3—C4—C5—C6	−0.9 (3)
C1—C2—C3—C4	0.0 (3)	C2—C1—C6—C5	0.6 (3)
C1—C2—C3—N1	−179.45 (17)	C2—C1—C6—N2	−178.74 (17)
O1—N1—C3—C4	−11.5 (3)	C4—C5—C6—C1	0.2 (3)
O2—N1—C3—C4	168.48 (18)	C4—C5—C6—N2	179.50 (17)
O1—N1—C3—C2	168.04 (19)	C7—N2—C6—C1	−176.0 (2)
O2—N1—C3—C2	−12.0 (3)	C7—N2—C6—C5	4.6 (3)
C2—C3—C4—C5	0.8 (3)	C6—N2—C7—O3	0.2 (4)
N1—C3—C4—C5	−179.76 (17)	C6—N2—C7—C7^i	179.5 (2)

Symmetry code: (i) −x+1, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O3^i	0.86	2.25	2.677 (2)	110
N2—H2A···O2^ii	0.86	2.32	3.148 (2)	161
C5—H5A···O3	0.93	2.29	2.898 (3)	122

Symmetry codes: (i) −x+1, −y, −z; (ii) x+1, −y−1/2, z+1/2.