Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536801014131/om6044sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536801014131/om6044Isup2.hkl |
CCDC reference: 175350
Crystals of the title compound were supplied by Dr Michael Chaykovsky, Naval Surface Warfare Center – White Oak, Silver Spring, MD. Crystal and reflection data were obtained using standard procedures (Butcher et al., 1995).
The ethylene (–NCH2CH2N–) backbone of the piperazine ring was found to be disordered over two conformations. Using the SHELXTL refinement package, the disordered ethylene segments of the two conformers shown in Fig. 3 were constrained to be equivalent in their bond distances and angles, while their occupancies refined to convergance at 0.596 (16) and 0.404 (16). H atoms were found in difference maps, except for those in the disordered segment, where they were generated to be in ideal tetrahedral positions. All H atoms were constrained in the refinement to ideal positions, with C—H distances of 0.97 or 0.98 Å, and angles as close to 109.5° as possible. Each was assigned a Uiso value equal to 1.2Ueq of the neighboring C atom.
Data collection: XSCANS (Siemens, 1994); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 1997a); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997b); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.
C5H6N4O7 | Dx = 1.828 Mg m−3 |
Mr = 234.14 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Pna21 | Cell parameters from 44 reflections |
a = 14.609 (2) Å | θ = 2.8–17.0° |
b = 8.4266 (12) Å | µ = 0.17 mm−1 |
c = 6.9097 (8) Å | T = 293 K |
V = 850.61 (19) Å3 | Plate, colorless |
Z = 4 | 0.45 × 0.39 × 0.03 mm |
F(000) = 480 |
Bruker P4 diffractometer | 805 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.000 |
Graphite monochromator | θmax = 27.5°, θmin = 2.8° |
2θ/ω scans | h = 0→18 |
Absorption correction: integration (Wuensch & Prewitt; 1965) | k = 0→10 |
Tmin = 0.947, Tmax = 0.992 | l = 0→8 |
1049 measured reflections | 3 standard reflections every 97 reflections |
1049 independent reflections | intensity decay: none |
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)] = 0.046 | H-atom parameters constrained |
wR(F2) = 0.111 | w = 1/[σ2(Fo2) + (0.047P)2 + 0.4504P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
1049 reflections | Δρmax = 0.24 e Å−3 |
165 parameters | Δρmin = −0.19 e Å−3 |
8 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.025 (6) |
C5H6N4O7 | V = 850.61 (19) Å3 |
Mr = 234.14 | Z = 4 |
Orthorhombic, Pna21 | Mo Kα radiation |
a = 14.609 (2) Å | µ = 0.17 mm−1 |
b = 8.4266 (12) Å | T = 293 K |
c = 6.9097 (8) Å | 0.45 × 0.39 × 0.03 mm |
Bruker P4 diffractometer | 805 reflections with I > 2σ(I) |
Absorption correction: integration (Wuensch & Prewitt; 1965) | Rint = 0.000 |
Tmin = 0.947, Tmax = 0.992 | 3 standard reflections every 97 reflections |
1049 measured reflections | intensity decay: none |
1049 independent reflections |
R[F2 > 2σ(F2)] = 0.046 | 8 restraints |
wR(F2) = 0.111 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.24 e Å−3 |
1049 reflections | Δρmin = −0.19 e Å−3 |
165 parameters |
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. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
C1 | 0.3886 (3) | 0.1680 (5) | 0.2406 (8) | 0.0290 (11) | |
H1A | 0.4002 | 0.1927 | 0.3770 | 0.035* | |
N2 | 0.3125 (3) | 0.2561 (6) | 0.1730 (7) | 0.0411 (11) | |
C3 | 0.3059 (5) | 0.2900 (10) | −0.0363 (10) | 0.036 (3) | 0.596 (16) |
H3A | 0.3065 | 0.1919 | −0.1097 | 0.044* | 0.596 (16) |
H3B | 0.2494 | 0.3460 | −0.0645 | 0.044* | 0.596 (16) |
C4 | 0.3848 (5) | 0.3879 (9) | −0.0876 (13) | 0.041 (3) | 0.596 (16) |
H4A | 0.3810 | 0.4895 | −0.0221 | 0.049* | 0.596 (16) |
H4B | 0.3853 | 0.4071 | −0.2260 | 0.049* | 0.596 (16) |
N5 | 0.4697 (3) | 0.3044 (5) | −0.0293 (8) | 0.0405 (11) | |
C6 | 0.4766 (3) | 0.1917 (5) | 0.1218 (8) | 0.0314 (11) | |
H6A | 0.5276 | 0.2192 | 0.2077 | 0.038* | |
O7 | 0.4915 (3) | 0.0358 (4) | 0.0382 (8) | 0.0531 (12) | |
C8 | 0.4323 (3) | −0.0699 (6) | 0.1083 (8) | 0.0352 (11) | |
O8 | 0.4364 (3) | −0.2070 (4) | 0.0759 (7) | 0.0507 (11) | |
O9 | 0.3697 (2) | 0.0002 (4) | 0.2185 (6) | 0.0368 (8) | |
C3' | 0.3122 (7) | 0.3628 (17) | 0.0065 (15) | 0.058 (6) | 0.404 (16) |
H3'A | 0.2521 | 0.3617 | −0.0532 | 0.070* | 0.404 (16) |
H3'B | 0.3246 | 0.4702 | 0.0497 | 0.070* | 0.404 (16) |
C4' | 0.3807 (5) | 0.3159 (17) | −0.1359 (12) | 0.053 (5) | 0.404 (16) |
H4'A | 0.3848 | 0.3944 | −0.2383 | 0.063* | 0.404 (16) |
H4'B | 0.3649 | 0.2144 | −0.1929 | 0.063* | 0.404 (16) |
N2A | 0.2585 (3) | 0.3273 (6) | 0.3134 (9) | 0.0484 (12) | |
O2A | 0.2037 (3) | 0.4269 (5) | 0.2554 (9) | 0.0699 (15) | |
O2B | 0.2681 (3) | 0.2838 (7) | 0.4779 (8) | 0.0776 (17) | |
N5A | 0.5444 (3) | 0.3976 (5) | −0.0631 (8) | 0.0380 (10) | |
O5A | 0.5339 (3) | 0.5113 (5) | −0.1697 (8) | 0.0592 (13) | |
O5B | 0.6160 (3) | 0.3612 (5) | 0.0127 (7) | 0.0586 (13) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.032 (2) | 0.028 (2) | 0.027 (2) | −0.0006 (19) | −0.002 (2) | −0.002 (2) |
N2 | 0.036 (2) | 0.048 (2) | 0.040 (2) | 0.015 (2) | 0.0058 (19) | 0.001 (2) |
C3 | 0.036 (5) | 0.042 (6) | 0.032 (5) | 0.013 (4) | 0.002 (4) | −0.006 (4) |
C4 | 0.042 (6) | 0.040 (5) | 0.041 (6) | −0.009 (4) | −0.018 (5) | −0.002 (5) |
N5 | 0.035 (2) | 0.044 (2) | 0.042 (3) | −0.009 (2) | 0.000 (2) | 0.014 (2) |
C6 | 0.034 (2) | 0.026 (2) | 0.035 (3) | −0.001 (2) | 0.005 (2) | 0.000 (2) |
O7 | 0.055 (2) | 0.0304 (18) | 0.074 (3) | −0.0002 (18) | 0.034 (2) | −0.006 (2) |
C8 | 0.040 (2) | 0.031 (3) | 0.035 (3) | 0.007 (2) | −0.002 (2) | 0.001 (2) |
O8 | 0.064 (2) | 0.0283 (19) | 0.060 (3) | 0.0048 (17) | 0.000 (2) | −0.0033 (19) |
O9 | 0.0356 (17) | 0.0313 (17) | 0.0433 (19) | −0.0046 (14) | 0.0072 (17) | −0.0018 (17) |
C3' | 0.058 (11) | 0.077 (14) | 0.040 (10) | 0.032 (10) | −0.008 (8) | −0.005 (10) |
C4' | 0.048 (9) | 0.086 (13) | 0.023 (7) | −0.032 (9) | −0.021 (6) | 0.005 (8) |
N2A | 0.037 (2) | 0.046 (3) | 0.062 (3) | 0.003 (2) | 0.009 (2) | −0.013 (3) |
O2A | 0.052 (2) | 0.054 (2) | 0.104 (4) | 0.024 (2) | 0.006 (3) | −0.011 (3) |
O2B | 0.060 (3) | 0.126 (5) | 0.046 (3) | 0.020 (3) | 0.017 (2) | −0.011 (3) |
N5A | 0.039 (2) | 0.032 (2) | 0.043 (3) | −0.0047 (18) | 0.009 (2) | −0.001 (2) |
O5A | 0.077 (3) | 0.037 (2) | 0.064 (3) | −0.004 (2) | 0.017 (2) | 0.015 (2) |
O5B | 0.034 (2) | 0.075 (3) | 0.067 (3) | −0.010 (2) | 0.003 (2) | 0.011 (3) |
C1—N2 | 1.416 (6) | C3'—C4' | 1.459 (10) |
C1—O9 | 1.449 (5) | N2A—O2B | 1.202 (8) |
C1—C6 | 1.539 (6) | N2A—O2A | 1.227 (7) |
N2—N2A | 1.387 (7) | N5A—O5B | 1.209 (6) |
N2—C3' | 1.460 (9) | N5A—O5A | 1.218 (6) |
N2—C3 | 1.477 (9) | C1—H1A | 0.9800 |
C3—C4 | 1.461 (10) | C3—H3A | 0.9700 |
C4—N5 | 1.483 (8) | C3—H3B | 0.9700 |
N5—N5A | 1.365 (5) | C4—H4A | 0.9700 |
N5—C6 | 1.415 (7) | C4—H4B | 0.9700 |
N5—C4' | 1.497 (8) | C6—H6A | 0.9800 |
C6—O7 | 1.451 (6) | C3'—H3'A | 0.9700 |
O7—C8 | 1.332 (6) | C3'—H3'B | 0.9700 |
C8—O8 | 1.178 (6) | C4'—H4'A | 0.9700 |
C8—O9 | 1.328 (6) | C4'—H4'B | 0.9700 |
N2—C1—O9 | 109.1 (4) | O5B—N5A—N5 | 118.1 (4) |
N2—C1—C6 | 114.3 (4) | O5A—N5A—N5 | 117.1 (5) |
O9—C1—C6 | 103.3 (4) | N2—C1—H1A | 110.0 |
N2A—N2—C1 | 116.3 (5) | O9—C1—H1A | 110.0 |
N2A—N2—C3' | 106.4 (6) | C6—C1—H1A | 110.0 |
C1—N2—C3' | 125.8 (5) | C4—C3—H3A | 110.3 |
N2A—N2—C3 | 124.3 (5) | N2—C3—H3A | 110.3 |
C1—N2—C3 | 118.4 (5) | C4—C3—H3B | 110.3 |
C4—C3—N2 | 107.2 (6) | N2—C3—H3B | 110.3 |
C3—C4—N5 | 109.0 (6) | H3A—C3—H3B | 108.5 |
N5A—N5—C6 | 117.1 (4) | C3—C4—H4A | 109.9 |
N5A—N5—C4 | 110.4 (4) | N5—C4—H4A | 109.9 |
C6—N5—C4 | 125.4 (5) | C3—C4—H4B | 109.9 |
N5A—N5—C4' | 124.9 (6) | N5—C4—H4B | 109.9 |
C6—N5—C4' | 117.9 (5) | H4A—C4—H4B | 108.3 |
N5—C6—O7 | 109.0 (4) | N5—C6—H6A | 110.0 |
N5—C6—C1 | 114.9 (4) | O7—C6—H6A | 110.0 |
O7—C6—C1 | 102.7 (3) | C1—C6—H6A | 110.0 |
C8—O7—C6 | 111.3 (4) | C4'—C3'—H3'A | 109.4 |
O8—C8—O9 | 125.5 (5) | N2—C3'—H3'A | 109.4 |
O8—C8—O7 | 123.6 (5) | C4'—C3'—H3'B | 109.4 |
O9—C8—O7 | 111.0 (4) | N2—C3'—H3'B | 109.4 |
C8—O9—C1 | 111.3 (4) | H3'A—C3'—H3'B | 108.0 |
C4'—C3'—N2 | 111.2 (7) | C3'—C4'—H4'A | 110.5 |
C3'—C4'—N5 | 106.4 (7) | N5—C4'—H4'A | 110.5 |
O2B—N2A—O2A | 126.4 (6) | C3'—C4'—H4'B | 110.5 |
O2B—N2A—N2 | 117.6 (5) | N5—C4'—H4'B | 110.5 |
O2A—N2A—N2 | 116.0 (6) | H4'A—C4'—H4'B | 108.6 |
O5B—N5A—O5A | 124.9 (5) |
Experimental details
Crystal data | |
Chemical formula | C5H6N4O7 |
Mr | 234.14 |
Crystal system, space group | Orthorhombic, Pna21 |
Temperature (K) | 293 |
a, b, c (Å) | 14.609 (2), 8.4266 (12), 6.9097 (8) |
V (Å3) | 850.61 (19) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.17 |
Crystal size (mm) | 0.45 × 0.39 × 0.03 |
Data collection | |
Diffractometer | Bruker P4 diffractometer |
Absorption correction | Integration (Wuensch & Prewitt; 1965) |
Tmin, Tmax | 0.947, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1049, 1049, 805 |
Rint | 0.000 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.046, 0.111, 1.04 |
No. of reflections | 1049 |
No. of parameters | 165 |
No. of restraints | 8 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.24, −0.19 |
Computer programs: XSCANS (Siemens, 1994), XSCANS, SHELXTL (Sheldrick, 1997a), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997b), SHELXTL.
The title compound, 2,5-diaza-2,5-dinitro-7,9-dioxabicyclo[4.3.0]nonan-8-one, (I), crystallizes in the orthorhombic space group Pna21, contains only C, H, N, and O, and has a density of 1.828 Mg m-3. The central core of the molecule contains no double bonds and consists of a cyclic carbonate ring fused to a piperazine ring. The molecule is not planar but is folded about the C1—C6 ring junction (the angle between the carbonate and piperazine rings is 61.8°). It is thus related to the other dense energetic cyclic carbonates, 6,8-diaza-6,8-dinitro-2,4-dioxabicyclo[3.3.0]octan-3-one (Gilardi & Butcher, 2001), and 4,5-bis(fluorodinitromethyl)-1,3-dioxolan-2-one (Ammon & Bhattacharjee, 1984). The synthesis of new energetic CHNO compounds that have high densities is a prime goal in the field of energetic compounds. However, 2,5-diaza-2,5-dinitro-7,9-dioxabicyclo[4.3.0]nonan-8-one has a much lower density than 6,8-diaza-6,8-dinitro-2,4-dioxabicyclo[3.3.0]octan-3-one (1.828 versus 1.953 Mg m-3). One factor which contributes to this is the conformational flexibility of the –NCH2CH2N– backbone of the piperazine ring, which is disordered over two conformations with occupancies of 0.60:0.40 (2). Metrical parameters for the cyclic carbonate ring are within the normal range observed for such compounds (as summarized in the Cambridge Structural Database; Allen et al., 1991). However, the metrical parameters of the piperazine ring are affected by the nitration of the N atoms, and the disorder of the ethylene backbone, and the connection with the cyclic carbonate ring. The major differences are found in the C1—N2 and C6—N5 bond lengths which, at 1.416 (5) Å, are considerably shortened from the expected value of 1.464 Å (Allen et al., 1991).