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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 2| February 2010| Page o430
https://doi.org/10.1107/S1600536810002217

Di­ethyl 1,4-bis­­(4-nitro­phen­yl)-1,4-di­hydro-1,2,4,5-tetra­zine-3,6-di­carboxyl­ate

Abdesselam Baouid,a Aicha Boudinaa and El Hassane Soumhib*

aEquipe de Chimie des Hétérocycles et Valorisation des Extraits des Plantes, Faculté des Sciences-Semlalia, Université Cadi Ayyad, Bd. Abdelkrim Khattabi, BP. 2390,40001, Marrakech, Morocco, and bEquipe de Chimie des Matériaux et de l'Environnement, FSTG-Marrakech, Université Cadi Ayyad, Bd. Abdelkrim Khattabi, BP. 549, Marrakech, Morocco
*Correspondence e-mail: eh_soumhi@yahoo.fr

(Received 5 January 2010; accepted 18 January 2010; online 23 January 2010)

The complete mol­ecule of the title compound, C20H18N6O8, is generated by a crystallographic twofold axis. The dihedral angle between the nitrobenzene rings is 43.5 (2)°. The central six-membered ring exhibits a boat conformation. In the crystal structure, weak inter­molecular C—H⋯O inter­actions are observed.

Related literature

For related literature on diazepine and triazepine derivatives, see: Barltrop et al. (1959[Barltrop, J. A., Richards, C. G., Russel, D. M. & Ryback, G. (1959). J. Chem. Soc. pp. 1132-1142.]); Boudina et al. (2006[Boudina, A., Baouid, A., Hasnaoui, A. & Essaber, M. (2006). Synth. Commun. 36, 573-579.]); El Hazazi et al. (2003[El Hazazi, S., Baouid, A., Hasnaoui, A. & Compain, P. (2003). Synth. Commun. 33, 19-27.]); Huisgen & Koch (1955[Huisgen, R. & Koch, H. J. (1955). Ann. Chem. 591, 200-231.]); Nabih et al. (2003[Nabih, K., Baouid, A., Hasnaoui, A., Selkti, M. & Compain, P. (2003). New J. Chem. 27, 1644-1648.]); Sharp & Hamilton (1946[Sharp, B. & Hamilton, C. S. (1946). J. Am. Chem. Soc. 68, 588-591.]). For related structures, see: Chiaroni et al. (1995[Chiaroni, A., Riche, C., Baouid, A., Hasnaoui, A., Benharref, A. & Lavergne, J.-P. (1995). Acta Cryst. C51, 1352-1355.]); El Hazazi et al. (2000[El Hazazi, S., Baouid, A., Hasnaoui, A. & Pierrot, M. (2000). Acta Cryst. C56, e457-e458.]).

[Scheme 1]

Experimental

Crystal data

  • C20H18N6O8

  • Mr = 470.40

  • Monoclinic, C 2/c

  • a = 20.739 (4) Å

  • b = 7.487 (2) Å

  • c = 14.587 (3) Å

  • β = 104.00 (2)°

  • V = 2197.7 (9) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 300 K

  • 0.30 × 0.15 × 0.10 mm
Data collection

  • Enraf–Nonius CAD-4 diffractometer

  • 3158 measured reflections

  • 2389 independent reflections

  • 1352 reflections with I > 2σ(I)

  • Rint = 0.022

  • 2 standard reflections every 60 min intensity decay: 1.0%
Refinement

  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.173

  • S = 1.04

  • 2389 reflections

  • 155 parameters

  • All H-atom parameters refined

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C6—H4⋯O2i 0.93 2.57 3.400 (4) 149
C9—H6⋯O1ii 0.97 2.60 3.294 (4) 129
Symmetry codes: (i) [-x+1, y, -z+{\script{3\over 2}}]; (ii) [-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1].

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 EXPRESS. Enraf-Nonius, Deft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: MolEN (Fair, 1990[Fair, C. K. (1990). MolEN. Enraf-Nonius, Delft, The Netherlands.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEPII (Johnson, 1976[Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810002217/is2514sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810002217/is2514Isup2.hkl

checkCIF report


Comment top

In order to prepare a new heterocyclic systems, our research team have been interested in the 1,3-dipolar cycloaddition reaction of nitrile oxides and nitrilimines toward diazepines, benzodiazepines, triazepines and benzotriazepines (El Hazazi et al., 2003; Nabih et al., 2003; Boudina et al., 2006). In this context, we directed our axe of research to examine reactivity of adducts-obtained from the 1,5-benzodiazepine (Barltrop et al., 1959) via 1,3-dipolar cycloaddition reaction of nitrilimines- with N-paranitrophenylnitrilimine (Sharp & Hamilton, 1946; Huisgen & Koch, 1955). This reaction provided to bicycloadduct and a new heterocycle (A). The new heterocycle (A) resulted from precursor ethyl paranitrophenylhydrazono-α-bromoglyoxylate by the action of triethylamine in dichloromethane at room temperature (Fig. 1).

The structure of product (A) was determined on the basis of NMR spectral data (1H and 13 C) and studied by single-crystal X-ray diffraction (Fig. 2). The asymmetric unit consists of one independent [C10H9N3O4] group that form one half of a molecule compound. The main geometric features of this group are in good agreement with those observed in similar compounds (Chiaroni et al., 1995; El Hazazi et al., 2000). The molecule of nominal compound is localized around a twofold rotation axis and exhibit a boat conformation in which N2 and N2a show the maximum deviation (0.3213 Å) from N3/N2/C7/N3i/N2i/C7i plane [symmetry code: (i) -x + 1, y, -z + 1/2].

Related literature top

For related literature on diazepine and triazepine derivatives, see: Barltrop et al. (1959); Boudina et al. (2006); El Hazazi et al. (2003); Huisgen & Koch (1955); Nabih et al. (2003); Sharp & Hamilton (1946). For related structures, see: Chiaroni et al. (1995); El Hazazi et al. (2000).

Experimental top

Triethylamine (0.8 mmol) in dichloromethane (2 ml) was added at room temperature to a stirred solution of ethyl paranitrophenylhydrazono-α-bromoglyoxylate (0.65 mmol) in dichloromethane (20 ml). The mixture was stirred at room temperature, washed with water and the aqueous phase was then extracted with ether (3×20 ml). The organic layer was dried over anhydrous sodium sulfate and then concentrated under reduced pressure and recrystallized from ethanol to afford the reaction product (A) (m.p. = 219–220 °C).

Refinement top

All H atoms were located in a difference map and refined using a riding model, with d(C—H) = 0.93–0.97 Å, and with Uiso(H) =1.2Ueq(C).

Structure description top

In order to prepare a new heterocyclic systems, our research team have been interested in the 1,3-dipolar cycloaddition reaction of nitrile oxides and nitrilimines toward diazepines, benzodiazepines, triazepines and benzotriazepines (El Hazazi et al., 2003; Nabih et al., 2003; Boudina et al., 2006). In this context, we directed our axe of research to examine reactivity of adducts-obtained from the 1,5-benzodiazepine (Barltrop et al., 1959) via 1,3-dipolar cycloaddition reaction of nitrilimines- with N-paranitrophenylnitrilimine (Sharp & Hamilton, 1946; Huisgen & Koch, 1955). This reaction provided to bicycloadduct and a new heterocycle (A). The new heterocycle (A) resulted from precursor ethyl paranitrophenylhydrazono-α-bromoglyoxylate by the action of triethylamine in dichloromethane at room temperature (Fig. 1).

The structure of product (A) was determined on the basis of NMR spectral data (1H and 13 C) and studied by single-crystal X-ray diffraction (Fig. 2). The asymmetric unit consists of one independent [C10H9N3O4] group that form one half of a molecule compound. The main geometric features of this group are in good agreement with those observed in similar compounds (Chiaroni et al., 1995; El Hazazi et al., 2000). The molecule of nominal compound is localized around a twofold rotation axis and exhibit a boat conformation in which N2 and N2a show the maximum deviation (0.3213 Å) from N3/N2/C7/N3i/N2i/C7i plane [symmetry code: (i) -x + 1, y, -z + 1/2].

For related literature on diazepine and triazepine derivatives, see: Barltrop et al. (1959); Boudina et al. (2006); El Hazazi et al. (2003); Huisgen & Koch (1955); Nabih et al. (2003); Sharp & Hamilton (1946). For related structures, see: Chiaroni et al. (1995); El Hazazi et al. (2000).

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1989); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1989); data reduction: MolEN (Fair, 1990); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The reaction scheme of the title compound.
[Figure 2] Fig. 2. The molecule structure of the title compound with 50% probability ellipsoids.
Diethyl 1,4-bis(4-nitrophenyl)-1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate top
Crystal data top
C20H18N6O8F(000) = 976
Mr = 470.40Dx = 1.422 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 25 reflections
a = 20.739 (4) Åθ = 10–15°
b = 7.487 (2) ŵ = 0.11 mm−1
c = 14.587 (3) ÅT = 300 K
β = 104.00 (2)°Prism, colourless
V = 2197.7 (9) Å30.30 × 0.15 × 0.10 mm
Z = 4
Data collection top
Enraf–Nonius CAD-4
diffractometer		Rint = 0.022
Radiation source: fine-focus sealed tubeθmax = 27.0°, θmin = 2.0°
Graphite monochromatorh = −26→25
ω/2θ scansk = −9→2
3158 measured reflectionsl = −1→18
2389 independent reflections2 standard reflections every 60 min
1352 reflections with I > 2σ(I) intensity decay: 1.0%
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.053Hydrogen site location: difference Fourier map
wR(F2) = 0.173All H-atom parameters refined
S = 1.04 w = 1/[σ2(Fo2) + (0.080P)2 + 0.9509P]
where P = (Fo2 + 2Fc2)/3
2389 reflections(Δ/σ)max < 0.001
155 parametersΔρmax = 0.27 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
Crystal data top
C20H18N6O8V = 2197.7 (9) Å3
Mr = 470.40Z = 4
Monoclinic, C2/cMo Kα radiation
a = 20.739 (4) ŵ = 0.11 mm−1
b = 7.487 (2) ÅT = 300 K
c = 14.587 (3) Å0.30 × 0.15 × 0.10 mm
β = 104.00 (2)°
Data collection top
Enraf–Nonius CAD-4
diffractometer		Rint = 0.022
3158 measured reflections2 standard reflections every 60 min
2389 independent reflections intensity decay: 1.0%
1352 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0530 restraints
wR(F2) = 0.173All H-atom parameters refined
S = 1.04Δρmax = 0.27 e Å−3
2389 reflectionsΔρmin = −0.26 e Å−3
155 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
O10.32809 (17)0.4483 (5)0.63327 (19)0.1695 (16)
O20.41693 (14)0.3584 (4)0.72174 (17)0.1199 (10)
O30.32302 (9)0.0896 (4)0.16616 (14)0.1091 (9)
O40.37172 (7)−0.0126 (3)0.31106 (12)0.0661 (5)
N10.38276 (16)0.3893 (3)0.6442 (2)0.0884 (8)
N20.47726 (9)0.2300 (3)0.32241 (12)0.0540 (5)
N30.54350 (8)0.1630 (3)0.33902 (12)0.0564 (5)
C10.40750 (14)0.3493 (3)0.55998 (17)0.0636 (7)
C20.36884 (14)0.3910 (4)0.4717 (2)0.0716 (8)
H10.32730.44300.46530.086*
C30.39257 (13)0.3545 (3)0.39242 (18)0.0654 (7)
H20.36780.38560.33250.078*
C40.45413 (11)0.2706 (3)0.40419 (15)0.0520 (5)
C50.49295 (12)0.2332 (3)0.49362 (16)0.0590 (6)
H30.53460.18110.50080.071*
C60.46928 (13)0.2741 (4)0.57236 (17)0.0660 (7)
H40.49500.25070.63280.079*
C70.43585 (10)0.1682 (3)0.23753 (15)0.0541 (6)
C80.36944 (12)0.0780 (4)0.23316 (18)0.0651 (7)
C90.30977 (13)−0.0998 (5)0.3205 (2)0.0867 (10)
H50.3033−0.21110.28540.104*
H60.2720−0.02270.29540.104*
C100.31545 (15)−0.1344 (5)0.4218 (2)0.1016 (12)
H70.2749−0.18640.42990.122*
H80.3236−0.02410.45620.122*
H90.3516−0.21530.44530.122*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.175 (3)0.249 (4)0.118 (2)0.124 (3)0.100 (2)0.043 (2)
O20.144 (2)0.165 (3)0.0653 (13)0.0037 (18)0.0534 (14)−0.0131 (15)
O30.0536 (11)0.199 (3)0.0711 (12)−0.0147 (14)0.0087 (10)0.0158 (15)
O40.0476 (9)0.0843 (12)0.0706 (10)−0.0101 (8)0.0223 (7)0.0018 (9)
N10.119 (2)0.0823 (17)0.0852 (18)0.0141 (15)0.0671 (17)0.0024 (14)
N20.0471 (10)0.0709 (13)0.0503 (10)0.0008 (9)0.0237 (8)−0.0022 (9)
N30.0449 (10)0.0765 (14)0.0516 (11)−0.0025 (9)0.0187 (8)−0.0018 (9)
C10.0872 (18)0.0555 (14)0.0619 (14)0.0005 (13)0.0450 (13)−0.0020 (12)
C20.0814 (17)0.0651 (16)0.0833 (18)0.0191 (13)0.0493 (15)0.0105 (14)
C30.0725 (15)0.0698 (17)0.0634 (14)0.0164 (13)0.0354 (12)0.0112 (12)
C40.0581 (13)0.0524 (13)0.0528 (12)−0.0049 (10)0.0276 (10)−0.0017 (10)
C50.0563 (13)0.0717 (16)0.0537 (13)−0.0029 (12)0.0225 (10)−0.0057 (12)
C60.0762 (17)0.0738 (17)0.0533 (13)−0.0050 (14)0.0258 (12)−0.0059 (12)
C70.0455 (11)0.0700 (15)0.0510 (12)0.0068 (11)0.0200 (10)0.0026 (11)
C80.0433 (12)0.099 (2)0.0579 (14)0.0004 (12)0.0217 (11)−0.0058 (14)
C90.0569 (15)0.121 (3)0.092 (2)−0.0301 (16)0.0365 (14)−0.0204 (18)
C100.0654 (17)0.130 (3)0.110 (2)−0.0187 (18)0.0216 (17)0.046 (2)
Geometric parameters (Å, º) top
O1—N11.191 (3)C3—C41.396 (3)
O2—N11.202 (3)C3—H20.9300
O3—C81.198 (3)C4—C51.386 (3)
O4—C81.314 (3)C5—C61.388 (3)
O4—C91.477 (3)C5—H30.9300
N1—C11.473 (3)C6—H40.9300
N2—C71.403 (3)C7—N3i1.290 (3)
N2—C41.422 (3)C7—C81.522 (3)
N2—N31.427 (3)C9—C101.478 (4)
N3—C7i1.290 (3)C9—H50.9700
C1—C61.371 (4)C9—H60.9700
C1—C21.378 (4)C10—H70.9600
C2—C31.389 (3)C10—H80.9600
C2—H10.9300C10—H90.9600
C8—O4—C9117.3 (2)C6—C5—H3120.2
O1—N1—O2121.5 (3)C1—C6—C5119.2 (2)
O1—N1—C1118.4 (3)C1—C6—H4120.4
O2—N1—C1120.0 (3)C5—C6—H4120.4
C7—N2—C4123.50 (18)N3i—C7—N2120.89 (19)
C7—N2—N3113.10 (17)N3i—C7—C8115.9 (2)
C4—N2—N3116.03 (18)N2—C7—C8122.52 (19)
C7i—N3—N2110.49 (18)O3—C8—O4126.6 (2)
C6—C1—C2122.0 (2)O3—C8—C7122.9 (2)
C6—C1—N1118.5 (2)O4—C8—C7110.5 (2)
C2—C1—N1119.5 (2)O4—C9—C10108.1 (2)
C1—C2—C3119.4 (2)O4—C9—H5110.1
C1—C2—H1120.3C10—C9—H5110.1
C3—C2—H1120.3O4—C9—H6110.1
C2—C3—C4118.9 (2)C10—C9—H6110.1
C2—C3—H2120.5H5—C9—H6108.4
C4—C3—H2120.5C9—C10—H7109.5
C5—C4—C3120.8 (2)C9—C10—H8109.5
C5—C4—N2120.6 (2)H7—C10—H8109.5
C3—C4—N2118.5 (2)C9—C10—H9109.5
C4—C5—C6119.6 (2)H7—C10—H9109.5
C4—C5—H3120.2H8—C10—H9109.5
C7—N2—N3—C7i42.9 (2)N2—C4—C5—C6180.0 (2)
C4—N2—N3—C7i−165.9 (2)C2—C1—C6—C5−2.1 (4)
O1—N1—C1—C6−177.2 (3)N1—C1—C6—C5179.1 (2)
O2—N1—C1—C61.1 (4)C4—C5—C6—C10.6 (4)
O1—N1—C1—C23.9 (4)C4—N2—C7—N3i167.8 (2)
O2—N1—C1—C2−177.7 (3)N3—N2—C7—N3i−43.5 (3)
C6—C1—C2—C30.6 (4)C4—N2—C7—C8−21.9 (4)
N1—C1—C2—C3179.4 (2)N3—N2—C7—C8126.8 (2)
C1—C2—C3—C42.3 (4)C9—O4—C8—O3−4.4 (4)
C2—C3—C4—C5−3.7 (4)C9—O4—C8—C7176.5 (2)
C2—C3—C4—N2178.5 (2)N3i—C7—C8—O3−40.8 (4)
C7—N2—C4—C5143.2 (2)N2—C7—C8—O3148.5 (3)
N3—N2—C4—C5−4.6 (3)N3i—C7—C8—O4138.4 (2)
C7—N2—C4—C3−39.0 (3)N2—C7—C8—O4−32.3 (3)
N3—N2—C4—C3173.1 (2)C8—O4—C9—C10−159.4 (3)
C3—C4—C5—C62.3 (4)
Symmetry code: (i) −x+1, y, −z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H4···O2ii0.932.573.400 (4)149
C9—H6···O1iii0.972.603.294 (4)129
Symmetry codes: (ii) −x+1, y, −z+3/2; (iii) −x+1/2, −y+1/2, −z+1.

Experimental details

Crystal data
Chemical formulaC20H18N6O8
Mr470.40
Crystal system, space groupMonoclinic, C2/c
Temperature (K)300
a, b, c (Å)20.739 (4), 7.487 (2), 14.587 (3)
β (°) 104.00 (2)
V (Å3)2197.7 (9)
Z4
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.30 × 0.15 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		3158, 2389, 1352
Rint0.022
(sin θ/λ)max (Å−1)0.638
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.173, 1.04
No. of reflections2389
No. of parameters155
H-atom treatmentAll H-atom parameters refined
Δρmax, Δρmin (e Å−3)0.27, −0.26

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1989), MolEN (Fair, 1990), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEPII (Johnson, 1976).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H4···O2i0.932.573.400 (4)148.6
C9—H6···O1ii0.972.603.294 (4)128.8
Symmetry codes: (i) −x+1, y, −z+3/2; (ii) −x+1/2, −y+1/2, −z+1.
 

References

First citationBarltrop, J. A., Richards, C. G., Russel, D. M. & Ryback, G. (1959). J. Chem. Soc. pp. 1132–1142.  CrossRef Web of Science Google Scholar
 First citationBoudina, A., Baouid, A., Hasnaoui, A. & Essaber, M. (2006). Synth. Commun. 36, 573–579.  Web of Science CrossRef CAS Google Scholar
 First citationChiaroni, A., Riche, C., Baouid, A., Hasnaoui, A., Benharref, A. & Lavergne, J.-P. (1995). Acta Cryst. C51, 1352–1355.  CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 66| Part 2| February 2010| Page o430
https://doi.org/10.1107/S1600536810002217
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