5-Nitro-2,3-bis­(thio­phen-2-yl)quinoxaline

The title compound, C₁₆H₉N₃O₂S₂, was synthesized via a condensation reaction in refluxing acetic acid. The dihedral angles between the mean plane of the quinoxaline unit and the thienyl rings are 35.16 (5)° and 24.94 (3)°.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.038
• wR factor = 0.076
• Data-to-parameter ratio = 29.2

checkCIF/PLATON results

No syntax errors found





Alert level B
PLAT230_ALERT_2_B Hirshfeld Test Diff for    O1       --N3       .        8.3 s.u.
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N3       --C4       .        9.2 s.u.

Alert level C
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.79 Report
PLAT230_ALERT_2_C Hirshfeld Test Diff for    S2       --C13      .        6.3 s.u.

Alert level G
PLAT005_ALERT_5_G No Embedded Refinement Details Found  in the CIF     Please Do !
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check

   0 ALERT level A = Most likely a serious problem - resolve or explain
   2 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   3 ALERT level G = General information/check it is not something unexpected

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 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
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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Computing details

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: OLEX2 (Bourhis et al., 2015).

5-Nitro-2,3-bis(thiophen-2-yl)quinoxaline

Crystal data

C16H9N3O2S2	Dx = 1.485 Mg m^−3
Mr = 339.38	Melting point: 445 K
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 9.6598 (4) Å	Cell parameters from 4761 reflections
b = 7.4249 (3) Å	θ = 4.2–34.7°
c = 11.2457 (6) Å	µ = 0.36 mm^−1
β = 109.745 (5)°	T = 293 K
V = 759.15 (6) Å^3	Block, yellow
Z = 2	0.42 × 0.34 × 0.21 mm
F(000) = 348

Data collection

Oxford Diffraction Xcalibur, Sapphire3 diffractometer	6073 independent reflections
Radiation source: Enhance (Mo) X-ray Source	3455 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
Detector resolution: 16.1790 pixels mm^-1	θmax = 34.7°, θmin = 4.2°
ω scans	h = −14→15
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −11→11
Tmin = 0.865, Tmax = 1.000	l = −17→17
12526 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.038	H-atom parameters constrained
wR(F^2) = 0.076	w = 1/[σ^2(Fo^2) + (0.0401P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.81	(Δ/σ)max < 0.001
6073 reflections	Δρmax = 0.43 e Å^−3
208 parameters	Δρmin = −0.15 e Å^−3
1 restraint	Absolute structure: Flack (1983)
Primary atom site location: iterative	Absolute structure parameter: 0.02 (4)

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.

H atoms were included in calculated positions with C-H distances of 0.93 Å and were included in the refinement in riding motion approximation with U_iso = 1.2 of the carrier atom.

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

	x	y	z	Uiso*/Ueq
S1	0.47899 (5)	0.46766 (7)	0.76512 (4)	0.06021 (14)
S2	−0.19846 (4)	0.56574 (5)	0.45980 (4)	0.04714 (10)
O1	−0.14872 (15)	0.6115 (2)	0.11787 (12)	0.0794 (4)
O2	−0.12755 (18)	0.3929 (3)	0.00033 (12)	0.0978 (6)
N1	0.33895 (13)	0.50828 (18)	0.48400 (11)	0.0434 (3)
N2	0.03464 (12)	0.50012 (16)	0.35820 (10)	0.0368 (3)
N3	−0.07726 (18)	0.4977 (3)	0.08793 (12)	0.0608 (4)
C1	0.24643 (14)	0.52968 (18)	0.54672 (12)	0.0358 (3)
C2	0.08928 (14)	0.51352 (17)	0.48202 (12)	0.0324 (3)
C3	0.13010 (16)	0.4937 (2)	0.29286 (13)	0.0390 (3)
C4	0.08067 (17)	0.4805 (2)	0.16013 (13)	0.0473 (4)
C5	0.1750 (2)	0.4561 (3)	0.09426 (17)	0.0645 (5)
H5	0.1394	0.4464	0.0067	0.077*
C6	0.3257 (2)	0.4459 (3)	0.16079 (18)	0.0727 (6)
H6	0.3903	0.4287	0.1164	0.087*
C7	0.3801 (2)	0.4603 (3)	0.28792 (17)	0.0647 (5)
H7	0.4811	0.4537	0.3299	0.078*
C8	0.28385 (16)	0.4853 (2)	0.35731 (14)	0.0435 (3)
C9	0.31323 (14)	0.5671 (2)	0.68209 (12)	0.0378 (3)
C10	0.26900 (17)	0.6793 (2)	0.75847 (14)	0.0447 (4)
H10	0.1831	0.7472	0.7308	0.054*
C11	0.36745 (19)	0.6812 (2)	0.88351 (15)	0.0554 (4)
H11	0.3529	0.7491	0.9478	0.066*
C12	0.48426 (19)	0.5748 (3)	0.90005 (15)	0.0630 (5)
H12	0.5599	0.5610	0.9769	0.076*
C13	−0.02054 (14)	0.50573 (18)	0.54585 (12)	0.0332 (3)
C14	−0.01082 (17)	0.4470 (2)	0.66529 (14)	0.0452 (4)
H14	0.0756	0.4075	0.7262	0.054*
C15	−0.1486 (2)	0.4545 (3)	0.68296 (16)	0.0554 (4)
H15	−0.1625	0.4191	0.7574	0.066*
C16	−0.25747 (19)	0.5175 (2)	0.58246 (17)	0.0552 (5)
H16	−0.3539	0.5329	0.5802	0.066*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0398 (2)	0.0812 (3)	0.0524 (2)	0.0186 (2)	0.00605 (16)	0.0062 (2)
S2	0.03174 (17)	0.0601 (2)	0.0503 (2)	0.00166 (19)	0.01476 (14)	−0.0002 (2)
O1	0.0607 (8)	0.1124 (12)	0.0540 (8)	0.0145 (9)	0.0049 (6)	−0.0004 (8)
O2	0.0919 (11)	0.1455 (15)	0.0512 (8)	−0.0414 (11)	0.0180 (7)	−0.0355 (9)
N1	0.0313 (5)	0.0576 (8)	0.0441 (7)	0.0034 (5)	0.0163 (5)	0.0023 (6)
N2	0.0324 (5)	0.0459 (7)	0.0336 (6)	−0.0032 (5)	0.0130 (4)	−0.0010 (5)
N3	0.0650 (9)	0.0883 (11)	0.0270 (6)	−0.0192 (9)	0.0130 (6)	−0.0009 (7)
C1	0.0309 (6)	0.0381 (9)	0.0380 (7)	0.0006 (5)	0.0110 (5)	0.0010 (6)
C2	0.0299 (6)	0.0335 (7)	0.0359 (7)	0.0008 (5)	0.0137 (5)	0.0011 (5)
C3	0.0416 (7)	0.0408 (7)	0.0388 (7)	−0.0044 (7)	0.0193 (6)	−0.0011 (6)
C4	0.0517 (9)	0.0560 (9)	0.0362 (7)	−0.0060 (8)	0.0172 (6)	−0.0046 (7)
C5	0.0788 (13)	0.0810 (12)	0.0454 (9)	−0.0026 (12)	0.0363 (9)	−0.0057 (10)
C6	0.0749 (13)	0.0977 (15)	0.0651 (12)	0.0070 (12)	0.0494 (11)	−0.0044 (11)
C7	0.0481 (9)	0.0942 (14)	0.0624 (11)	0.0057 (10)	0.0326 (8)	−0.0038 (11)
C8	0.0393 (7)	0.0503 (8)	0.0463 (8)	0.0020 (7)	0.0214 (6)	−0.0015 (7)
C9	0.0300 (6)	0.0451 (7)	0.0361 (7)	0.0024 (7)	0.0085 (5)	0.0068 (7)
C10	0.0380 (8)	0.0513 (9)	0.0404 (8)	0.0033 (7)	0.0074 (6)	−0.0021 (7)
C11	0.0552 (10)	0.0658 (11)	0.0422 (9)	−0.0047 (9)	0.0126 (7)	−0.0075 (8)
C12	0.0515 (9)	0.0874 (13)	0.0394 (8)	0.0023 (11)	0.0014 (7)	0.0092 (10)
C13	0.0286 (6)	0.0369 (7)	0.0355 (7)	−0.0008 (5)	0.0125 (5)	−0.0013 (6)
C14	0.0446 (8)	0.0523 (9)	0.0424 (8)	−0.0013 (8)	0.0195 (6)	0.0057 (7)
C15	0.0598 (10)	0.0686 (11)	0.0483 (9)	−0.0147 (10)	0.0321 (8)	−0.0071 (9)
C16	0.0420 (8)	0.0686 (12)	0.0664 (11)	−0.0068 (8)	0.0331 (8)	−0.0123 (9)

Geometric parameters (Å, º)

S1—C9	1.7234 (14)	C5—C6	1.396 (3)
S1—C12	1.6986 (19)	C6—H6	0.9300
S2—C13	1.7219 (14)	C6—C7	1.351 (2)
S2—C16	1.6992 (17)	C7—H7	0.9300
O1—N3	1.209 (2)	C7—C8	1.414 (2)
O2—N3	1.220 (2)	C9—C10	1.365 (2)
N1—C1	1.3218 (17)	C10—H10	0.9300
N1—C8	1.3528 (19)	C10—C11	1.407 (2)
N2—C2	1.3155 (17)	C11—H11	0.9300
N2—C3	1.3602 (17)	C11—C12	1.338 (2)
N3—C4	1.472 (2)	C12—H12	0.9300
C1—C2	1.4498 (18)	C13—C14	1.3849 (19)
C1—C9	1.4653 (19)	C14—H14	0.9300
C2—C13	1.4693 (18)	C14—C15	1.411 (2)
C3—C4	1.409 (2)	C15—H15	0.9300
C3—C8	1.417 (2)	C15—C16	1.341 (3)
C4—C5	1.367 (2)	C16—H16	0.9300
C5—H5	0.9300
C12—S1—C9	91.46 (8)	N1—C8—C3	120.30 (12)
C16—S2—C13	91.95 (8)	N1—C8—C7	119.98 (14)
C1—N1—C8	118.73 (12)	C3—C8—C7	119.66 (14)
C2—N2—C3	118.14 (12)	C1—C9—S1	118.96 (11)
O1—N3—O2	124.17 (17)	C10—C9—S1	110.59 (10)
O1—N3—C4	119.36 (15)	C10—C9—C1	130.37 (13)
O2—N3—C4	116.47 (19)	C9—C10—H10	123.7
N1—C1—C2	120.28 (12)	C9—C10—C11	112.66 (14)
N1—C1—C9	115.93 (12)	C11—C10—H10	123.7
C2—C1—C9	123.78 (12)	C10—C11—H11	123.6
N2—C2—C1	121.01 (12)	C12—C11—C10	112.76 (15)
N2—C2—C13	114.61 (11)	C12—C11—H11	123.6
C1—C2—C13	124.37 (12)	S1—C12—H12	123.7
N2—C3—C4	121.73 (13)	C11—C12—S1	112.51 (12)
N2—C3—C8	120.66 (13)	C11—C12—H12	123.7
C8—C3—C4	117.41 (12)	C2—C13—S2	117.62 (10)
C3—C4—N3	119.71 (13)	C14—C13—S2	110.76 (10)
C5—C4—N3	117.98 (14)	C14—C13—C2	131.50 (13)
C5—C4—C3	122.29 (15)	C13—C14—H14	124.3
C4—C5—H5	120.6	C13—C14—C15	111.45 (14)
C4—C5—C6	118.83 (16)	C15—C14—H14	124.3
C6—C5—H5	120.6	C14—C15—H15	123.1
C5—C6—H6	119.1	C16—C15—C14	113.81 (14)
C7—C6—C5	121.71 (15)	C16—C15—H15	123.1
C7—C6—H6	119.1	S2—C16—H16	124.0
C6—C7—H7	120.0	C15—C16—S2	112.01 (12)
C6—C7—C8	120.09 (17)	C15—C16—H16	124.0
C8—C7—H7	120.0