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The title compound, C7H12N4O2, was obtained by nitro­sation of the aminal cage (2R,7R,11S,16S)-1,8,10,17-tetra­aza­penta­cyclo­[8.8.1.18,17.02,7.011,16]icosane. The crystal structure is a racemic mixture of RR and SS enantio­mers. The asymmetric unit contains two crystallographically independent half-mol­ecules, one having two partially occupied conformers with refined occupancy factors of 0.747 (3) and 0.253 (3). The mol­ecules sit across twofold axes. The unique mol­ecules each form chains parallel to [001], with mol­ecules connected by inter­molecular C-H...O hydrogen bonds. The bonding between adjacent chains is weak. The analysis of eight different crystals confirmed the presence of disordered and nondisordered mol­ecules in the same structure as a regular feature.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270111046397/uk3034sup1.cif
Contains datablocks global, I

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270111046397/uk3034Isup2.hkl
Contains datablock I

cml

Chemical Markup Language (CML) file https://doi.org/10.1107/S0108270111046397/uk3034Isup3.cml
Supplementary material

CCDC reference: 862243

Comment top

Our group (at the Universidad Nacional de Colombia, Bogotá) has previously explored the reaction of nitrous acid with cyclic aminals, which are actually tertiary amines. Previously, we reported the synthesis and complete characterization by NMR of a heterocyclic secondary N,N'-dinitrosamine by reaction of the macrocyclic aminal 1,3,6,8-tetraazatricyclo[4.4.1.13,8]dodecane [TATD, (1)] with nitrous acid (sodium nitrite/HCl) (Rivera et al., 1997). The chemistry of N-nitrosamines is a subject of considerable interest with regard to their strong carcinogenic and mutagenic properties (Di Salvo et al., 2008). Recently, we have been interested in the cyclic aminal (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo[8.8.1.18,17.02,7.011,16]icosane, (2). In a further exploration of its synthetic utility, aminal (2) was reacted with sodium nitrite in an acidic medium. We found that the nitrosation of (2) was similar to the reaction of (1); it also proceeded under mild conditions (273–278 K) to give the corresponding title compound, (3aRS,7aRS)-1,3-dinitrosooctahydro-1H-benzimidazole, (I), in 70–75% yields (see scheme). The structure of the N-nitrosoamine obtained was investigated in solution and in the solid state by IR, NMR (1H and 13C, and short- and long-range coupling experiments), mass spectrometry and X-ray methods. Crystallographic information on N,N'-dinitroso compounds in the Cambridge Structural Database (CSD; Allen, 2002) is limited. In particular, the O N—NCH2N—NO fragment is quite rare and a search of the CSD (Version 5.32) for compounds containing structures that match this fragment retrieved no hits.

As reported in the literature, N-nitroso compounds typically display two absorption bands in their IR spectra due to stretching of the NO and N—N bonds between 1460 and 1440 cm-1, and near 1050 cm-1, respectively (Sousa et al., 2005). These characteristic bands are observed in the IR spectrum of (I) at 1455 and 1112 cm-1.

The 1H NMR spectrum of (I) only shows signals corresponding to the syn isomer. The influence of the nitroso group on the chemical shift values is evident in the signals of the aminal protons of the imidazolidine ring, which appear at a lower field (5.20 p.p.m.) than the corresponding aminal protons in the aminal precursor (2).

The molecular structure of (I) is presented in Fig. 1, and selected geometric parameters are given in Table 1. The compound is monoclinic (space group P2/c), with two crystallographically independent half-molecules (half-molecule M1 formed by atoms O1/C1–C4 and half-molecule M2 formed by atoms O2/C5–C8) in the asymmetric unit and overall Z = 4. Molecules M1 and M2 both have twofold symmetry, with atoms C1 (for M1) and C5 (for M2) located on the twofold axes. The cyclohexane ring in molecule M2 is disordered and adopts two unequally occupied orientations. Molecule M1 is fully ordered.

In the first attempt to model the disorder, we described two overlapping conformations A and B of M2. The positions of the atoms were refined independently, whereas the displacement parameters (isotropic for close positions and anisotropic for farther positions) were constrained so that they were the same for each pair of atoms arising from the corresponding split position; the site-occupancy factors were kept the same for all atoms of A and the complement of one for B. Refinement of this structural model contained 120 parameters and converged with Robs = 0.043, with the largest difference-map residuals being 0.30 and -0.31 e Å-3, indicating a good fit of the structural model to the experimental data. The occupancies of conformations A and B refined to 0.734 (2):0.266 (2), respectively. However, the refined geometries of conformations A and B are significantly different, particularly for the N—NO groups.

Prior to drawing conclusions from the differences between conformations A and B, we had to test whether the diffraction data were sufficiently sensitive for refinement of such weakly occupied positions of B. Indeed, the average electron density of carbon with an occupancy of 0.266 (2) is less than two H atoms. For this test, we used a rigid-body approach available in the crystallographic package JANA2006 (Petříček et al., 2006). The atoms of position A of molecule M2 obtained from the structure model described above were taken as the model molecule. Atom C5, sitting on the twofold axis, was used as a reference point for the calculation of symmetry restrictions of molecular parameters. Together with the parameters of the model molecule, we refined a translation vector and three rotation angles transforming the model molecule (including orientation of anisotropic displacement parameters) to the actual position A, and another translation vector and three rotation angles transforming the model molecule to the actual position B. The reference point located on the twofold axis led to symmetry restrictions of the translation vectors such that molecules A and B were both still located on the twofold axis. Since the model molecule was originally taken from position A of M2, the first translation vector was very short and the corresponding rotation angles zero. The occupancy factors converged to 0.738 (3) and 0.262 (3) for A and B, respectively, which are near to the values from the split-atom model. Surprisingly, the resulting R value was 0.04 and the largest difference-map residuals were 0.27 and -0.27 e Å-3 (i.e. slightly better than the previous model), whereas the number of refined parameters (124) remained almost the same. This meant that the different geometries of A and B were not confirmed and should both be considered identical.

A CIF file was generated as the free atomic model because the rigid-body approach is not included in the CIF dictionary. Therefore, refinement of the structure model included in the CIF would bring back our free atomic model with different molecular geometries for A and B. As a logical step, we constructed another rigid-body model with three positions for the model molecule, including configurations A and B of M2, and nondisordered molecule M1. Refinement of this structure model had 71 parameters and converged with Robs = 0.054; the largest difference-map residuals were 0.43 and -0.32 e Å-3. Taking into account the considerably lower number of parameters, we could conclude that all molecules of (I) have almost the same geometry within the resolution of our diffraction experiment. However, the increase in the R value of the last structure model by 0.014 can not be ignored, and some slight differences in geometry between M1 and M2 can not be excluded. Thus, we took as the final structure model the one with independently refined M1 and M2 molecules.

X-ray crystallography reveals a nearly planar structure for the N atom in the heterocyclic five-membered ring in both molecules (M1 and M2), where the sums of the internal bond angles around the N atoms are 360.08 (10) and 360.0 (2)°, respectively. The presence of planar N atoms in all fused five-membered rings imposes some conformational rigidity on these molecules, which is evident from the values of the relevant torsion angles for M1 [C1—N1—N2—O1 = -3.2 (2)°, C2—N1—C1—N1i = 13.73 (12)°, C1—N1—C2—C2i = -34.42 (17)° and N1—C2—C2i—N1i = 38.99 (17)°] and the puckering parameters Q = 0.391 (2) Å and ϕ = 126.0 (2)° (Cremer & Pople, 1975). These values indicate that the N1—C1—N1i—C2—C2i five-membered ring adopts a conformation that is significantly deformed (twisted on the C2—C2i bond), with the C atoms oriented endo and exo with respect to the reference plane defined by atoms N1, C1 and N1i [symmetry code: (i) -x + 1, y, -z + 3/2]. This orientation is very close to a half-chair conformation. Analogously, the disordered molecule (M2) shows puckering parameters and torsion angles that indicate a conformation twisted around the C6—C6i bond. In addition, the N—NO moieties are nearly coplanar with the imidazolidine rings (mean planes of the imidazolidine rings N1—C1—N1i and N3—C5—N3i), making dihedral angles of -0.1 (3)° and -3.2 (2), respectively.

The geometry of the N—NO group in M1 is similar to that observed in related compounds (Simonov et al., 2005), as is evident from the O1—N2 bond length of 1.2482 (18) Å, which is between a double bond (1.13 Å) and a single bond (1.49 Å) (Hartung et al., 1996). This type of structure has been observed in other N-nitroso amines (Simonov et al., 2005) where it was associated with the possibility of conjugation and redistribution of the electron density, in contradiction with the representation shown in the scheme above. In contrast, the geometric parameters in M2 fall within the mean for N—O bond distances (Simonov et al., 2005). The N4A—O2A distance [In which compound? That in M2 is identical to M1] is slightly longer than that in M1 [N4A—O2A = 1.266 (3) Å]. The fused six-membered ring for M2A (C6A/C7A/C8A/C8Ai/C7Ai/C6Ai) exhibits a chair conformation with puckering parameters Q = 0.571 (3) Å, θ = 172.7 (3)° and ϕ = 150 (2)°, and the bond lengths and angles are distorted with respect to the normal bond values for an ideal chair conformation of a cyclohexane ring (1.528 Å and 111.1°, respectively; Geise et al., 1971). Furthermore, the C—C bonds shared by the two rings and their vicinal C—C bonds are shorter than the other C—C distances in the cyclohexyl ring. The lengthening of these bonds might be attributed to the polarization effect of the N—NO group. By comparison, the six-membered ring of M1 (C2/C3/C4/C2i/C3i/C4i) adopts a chair conformation with puckering parameters Q = 0.608 (2) Å, θ = 172.90 (3)° and ϕ = 150.0 (15)°.

In the crystal structure of (I) (Fig. 2), C—H···O hydrogen bonds involving the methine groups of the fused rings link adjacent molecules of the same independent type into centrosymmetric dimers which then extend, by virtue of the molecular two-fold symmetry, into extended chains propagating along the c axis. In addition, the chains of M1 and M2 molecules are cross-linked by another weak intermolecular C—H···O hydrogen bond (Table 2). Atom C5 acts as a hydrogen-bond donor to atom O1, producing a chain running parallel to the [001] direction. It is interesting to compare the hydrogen-bond pattern of the nondisordered molecule (M1) with that of the disordered molecule (M2). In M1, where the cyclohexane ring does not exhibit molecular disorder, two intermolecular hydrogen bonds link the molecules to their M1 neighbours and should be structurally important. For the disordered molecule, only an intermolecular hydrogen bond is significant, and bonding with adjacent chains is very weak.

We believe that the differences in the geometric parameters and hydrogen-bond geometry between M1 and M2 might be rationalized in terms of electronic delocalization of the N—NO moiety and/or dipole interactions (Abraham et al., 1972). To provide more relevant data for this theory, quantum chemical calculations were performed on the isolated atomic coordinates derived from the X-ray diffraction experiment to obtain optimized structural parameters. For both structures, full optimizations using ab initio Hartree–Fock (HF) and density functional theory with the 6–31G** basis set were performed using the GAUSSIAN98 program package (Frisch et al., 1998). The results for both methods show that both molecules converge to the same minimum. Selected optimized and X-ray crystallographic bond lengths and angles are collected in Table 1. The largest differences are for the non-disordered molecule (M1), suggesting that the computed geometric parameters are in close agreement with the disordered molecule (M2).

Related literature top

For related literature, see: Abraham et al. (1972); Allen (2002); Cremer & Pople (1975); Di Salvo, Estrin, Leitus & Doctorovich (2008); Frisch (1998); Geise et al. (1971); Glister et al. (2005); Hartung et al. (1996); Petříček et al. (2006); Rivera et al. (1997); Simonov et al. (2005); Sousa et al. (2005).

Experimental top

A solution in ethanol and water (1:1 v/v, 5 ml) of aminal (2R,7R,11S,16S)-1,8,10,17-tetraazapentacyclo[8.8.1.18,17.02,7.011,16]icosane, (2) (407 mg, 1.48 mmol), prepared beforehand following a previously described procedure (Glister et al., 2005), was cooled to 283 K using an ice–water bath. The solution was treated with sodium nitrite (450 mg, 6.50 mmol) and concentrated hydrochloric acid was added dropwise until pH 3 was obtained. The mixture was stirred for 15 min until precipitation of a colourless solid occurred. The resulting solid was collected by filtration and recrystallized from propan-2-ol (yield 70%, m.p. 413–415 K). Single crystals of racemic (I) were grown from a propan-2-ol solution by slow evaporation of the solvent at room temperature over a period of about two weeks.

Refinement top

H atoms were positioned geometrically and kept in ideal positions during the refinement, with C—H = 0.96 Å and Uiso(H) = 1.2Ueq(parent). One of the molecules is disordered and its atoms are divided over two sites [occupancy ratio 0.738 (3):0.262 (3)]. In order to describe the disordered molecule, orientational disorder of the complete M2 molecule as a rigid body was applied; see Comment for details.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SIR2002 (Burla et al., 2003); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: JANA2006 (Petříček et al., 2006).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), including two independent molecules and showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms in the disordered molecule have been omitted for clarity. [Symmetry codes: (i) -x + 2, y, -z + 3/2; (ii) -x + 1, y, -z + 1/2.]
[Figure 2] Fig. 2. The packing of the molecules of (I), viewed along the b axis. Hydrogen bonds are drawn as dashed lines (in the electronic version of the journal, blue dashed lines indicate weak inter-chain hydrogen bonds). Only H atoms participating in hydrogen bonds are shown. [Symmetry codes: (iii) -x + 2, y + 1, -z + 1; (iv) -x + 1, -y + 1, -z.]
(3aRS,7aRS)-1,3-dinitroso-2,3,3a,4,5,6,7,7a- octahydro-1H-benzimidazole top
Crystal data top
C7H12N4O2F(000) = 392
Mr = 184.2Dx = 1.393 Mg m3
Monoclinic, P2/cCu Kα radiation, λ = 1.5418 Å
Hall symbol: -P 2ycCell parameters from 3902 reflections
a = 10.8128 (8) Åθ = 4.6–62.1°
b = 8.4293 (4) ŵ = 0.88 mm1
c = 10.9321 (9) ÅT = 120 K
β = 118.192 (8)°Plate, colourless
V = 878.20 (12) Å30.37 × 0.18 × 0.07 mm
Z = 4
Data collection top
Agilent Xcalibur
diffractometer with Atlas (Gemini Ultra Cu) detector
1376 independent reflections
Radiation source: Enhance Ultra (Cu) X-ray Source1163 reflections with I > 3σ(I)
Mirror monochromatorRint = 0.024
Detector resolution: 10.3784 pixels mm-1θmax = 62.2°, θmin = 4.6°
Rotation method data acquisition using ω scansh = 1112
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
k = 99
Tmin = 0.549, Tmax = 1.000l = 1212
6725 measured reflections
Refinement top
Refinement on F249 constraints
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.115Weighting scheme based on measured s.u.'s w = 1/(σ2(I) + 0.0016I2)
S = 1.92(Δ/σ)max = 0.020
1376 reflectionsΔρmax = 0.28 e Å3
122 parametersΔρmin = 0.25 e Å3
0 restraints
Crystal data top
C7H12N4O2V = 878.20 (12) Å3
Mr = 184.2Z = 4
Monoclinic, P2/cCu Kα radiation
a = 10.8128 (8) ŵ = 0.88 mm1
b = 8.4293 (4) ÅT = 120 K
c = 10.9321 (9) Å0.37 × 0.18 × 0.07 mm
β = 118.192 (8)°
Data collection top
Agilent Xcalibur
diffractometer with Atlas (Gemini Ultra Cu) detector
1376 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
1163 reflections with I > 3σ(I)
Tmin = 0.549, Tmax = 1.000Rint = 0.024
6725 measured reflectionsθmax = 62.2°
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.115H-atom parameters constrained
S = 1.92Δρmax = 0.28 e Å3
1376 reflectionsΔρmin = 0.25 e Å3
122 parameters
Special details top

Experimental. CrysAlisPro (Agilent Technologies, 2010); empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

1H NMR (CDCl3, 400 MHz, δ, p.p.m.): 1.64 (2H, m), 1.99 (2H, m), 2.16 (2H, m), 2.88 (2H, m), 3.84 (2H, m), 5.20 (2H, s, NCH2N).

13C NMR (CDCl3, 100 MHz, δ, p.p.m.): 23.8, 27.5, 60.8, 65.5.

MS-ESI in its positive mode m/z: [M+Na]+ calculated for C7H12N4O2Na: 207.0858, found: 207.0858.

Refinement. The refinement was carried out against all reflections. The conventional R-factor is always based on F. The goodness of fit as well as the weighted R-factor are based on F and F2 for refinement carried out on F and F2, respectively. The threshold expression is used only for calculating R-factors etc. and it is not relevant to the choice of reflections for refinement.

The program used for refinement, Jana2006, uses the weighting scheme based on the experimental expectations, see _refine_ls_weighting_details, that does not force S to be one. Therefore the values of S are usually larger than the ones from the SHELX program.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
O10.82871 (14)0.35148 (13)0.49054 (13)0.0297 (6)
N10.94408 (6)0.53528 (13)0.63361 (13)0.0224 (6)
N20.85648 (16)0.49615 (16)0.50649 (14)0.0256 (6)
C110.42468 (12)0.750.0237 (10)
C20.9961 (2)0.69770 (18)0.67919 (16)0.0224 (7)
C30.9105 (2)0.83710 (17)0.59407 (18)0.0246 (7)
C40.9873 (2)0.98577 (19)0.67535 (19)0.0324 (9)
H110.924370.3652930.750270.0284*
H21.0805360.7152760.6727430.0268*
H310.8184450.8331230.5866710.0296*
H320.908760.8368540.5054710.0296*
H410.934581.0784490.6284980.0389*
H421.0752760.9957040.6744350.0389*
O2A0.6431 (4)0.35254 (17)0.1192 (5)0.0333 (12)0.747 (3)
N3A0.58317 (10)0.5367 (3)0.21626 (10)0.0209 (9)0.747 (3)
N4A0.6542 (4)0.4976 (3)0.1525 (4)0.0333 (14)0.747 (3)
C5A0.50.42546 (18)0.250.0232 (14)0.747 (3)
C6A0.5741 (2)0.6984 (3)0.2605 (2)0.0237 (10)0.747 (3)
C7A0.6020 (3)0.8380 (3)0.1913 (3)0.0289 (12)0.747 (3)
C8A0.5719 (3)0.9873 (3)0.2520 (3)0.0364 (13)0.747 (3)
H5A0.4417120.3634440.1694470.0279*0.747 (3)
H6A0.6491680.7146730.3527250.0285*0.747 (3)
H71A0.5398590.834010.0932150.0347*0.747 (3)
H72A0.6987410.8374530.2119730.0347*0.747 (3)
H81A0.644151.0012960.3460170.0437*0.747 (3)
H82A0.5812421.0790940.2049940.0437*0.747 (3)
O2B0.6626 (5)0.3451 (4)0.1401 (4)0.0333 (13)0.253 (3)
N3B0.54902 (11)0.5292 (5)0.17961 (9)0.0209 (9)0.253 (3)
N4B0.6284 (4)0.4901 (5)0.1249 (3)0.0333 (14)0.253 (3)
C5B0.50.4180 (4)0.250.0232 (14)0.253 (3)
C6B0.5001 (2)0.6909 (5)0.1811 (2)0.0237 (10)0.253 (3)
C7B0.5787 (4)0.8305 (5)0.1663 (3)0.0289 (12)0.253 (3)
C8B0.5089 (3)0.9799 (5)0.1844 (2)0.0364 (13)0.253 (3)
H5B0.5776590.3559730.3152950.0279*0.253 (3)
H6B0.4124350.7072020.0987510.0285*0.253 (3)
H71B0.6746480.8265390.237820.0347*0.253 (3)
H72B0.5713360.8299820.075290.0347*0.253 (3)
H81B0.4188770.9938250.1043370.0437*0.253 (3)
H82B0.5608311.0716230.1830960.0437*0.253 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0311 (8)0.0250 (7)0.0290 (7)0.0035 (5)0.0109 (7)0.0101 (5)
N10.0263 (9)0.0184 (7)0.0174 (7)0.0000 (6)0.0061 (7)0.0011 (5)
N20.0257 (9)0.0284 (8)0.0204 (8)0.0001 (6)0.0089 (7)0.0055 (6)
C10.0263 (15)0.0194 (11)0.0211 (12)00.0076 (12)0
C20.0263 (11)0.0189 (8)0.0216 (9)0.0024 (7)0.0110 (8)0.0013 (7)
C30.0286 (11)0.0226 (9)0.0223 (8)0.0009 (7)0.0117 (8)0.0041 (7)
C40.0368 (12)0.0199 (9)0.0358 (11)0.0010 (8)0.0133 (10)0.0047 (8)
O2A0.0304 (16)0.0294 (7)0.0414 (19)0.0078 (9)0.0180 (15)0.0028 (9)
N3A0.0209 (12)0.0170 (7)0.0255 (12)0.0008 (8)0.0116 (10)0.0004 (8)
N4A0.0353 (19)0.0294 (9)0.043 (2)0.0051 (11)0.0254 (17)0.0011 (11)
C5A0.021 (2)0.0188 (12)0.0304 (19)00.0125 (12)0
C6A0.0247 (13)0.0155 (10)0.0289 (13)0.0002 (8)0.0110 (12)0.0010 (8)
C7A0.0284 (19)0.0235 (10)0.0300 (15)0.0072 (11)0.0098 (14)0.0008 (11)
C8A0.0392 (17)0.0189 (10)0.0436 (18)0.0039 (9)0.0133 (16)0.0022 (9)
O2B0.042 (2)0.0294 (7)0.0317 (14)0.0042 (10)0.0196 (15)0.0067 (8)
N3B0.0255 (14)0.0170 (7)0.0215 (11)0.0003 (9)0.0122 (10)0.0008 (7)
N4B0.042 (2)0.0294 (9)0.0380 (16)0.0004 (12)0.0263 (17)0.0049 (10)
C5B0.031 (2)0.0188 (12)0.0219 (19)00.0139 (13)0
C6B0.0297 (15)0.0155 (10)0.0246 (12)0.0011 (9)0.0117 (12)0.0001 (7)
C7B0.0314 (18)0.0235 (10)0.0274 (16)0.0020 (12)0.0102 (14)0.0065 (10)
C8B0.046 (2)0.0189 (10)0.0378 (15)0.0029 (10)0.0143 (16)0.0033 (9)
Geometric parameters (Å, º) top
O1—N21.2482 (18)C6A—H6A0.96
N1—N21.3014 (17)C7A—C8A1.528 (4)
N1—C11.4583 (13)C7A—H71A0.96
N1—C21.4746 (18)C7A—H72A0.96
C1—H110.96C8A—C8Aii1.535 (4)
C1—H11i0.96C8A—H81A0.96
C2—C2i1.510 (3)C8A—H82A0.96
C2—C31.513 (2)O2B—N4B1.266 (5)
C2—H20.96N3B—N4B1.299 (5)
C3—C41.534 (2)N3B—C5B1.462 (3)
C3—H310.96N3B—C6B1.465 (5)
C3—H320.96C5B—H5B0.96
C4—C4i1.522 (3)C5B—H5Bii0.96
C4—H410.96C6B—C6Bii1.507 (4)
C4—H420.96C6B—C7B1.505 (6)
O2A—N4A1.266 (3)C6B—H6B0.96
N3A—N4A1.299 (5)C7B—C8B1.528 (6)
N3A—C5A1.462 (2)C7B—H71B0.96
N3A—C6A1.465 (3)C7B—H72B0.96
C5A—H5A0.96C8B—C8Bii1.535 (4)
C5A—H5Aii0.96C8B—H81B0.96
C6A—C6Aii1.507 (4)C8B—H82B0.96
C6A—C7A1.505 (4)
N2—N1—C1124.21 (10)C6Aii—C6A—H6A118.0728
N2—N1—C2124.42 (12)C7A—C6A—H6A98.3342
C1—N1—C2111.35 (9)C6A—C7A—C8A106.9 (3)
O1—N2—N1113.73 (12)C6A—C7A—H71A109.4717
N1—C1—N1i100.52 (9)C6A—C7A—H72A109.4715
N1—C1—H11109.4714C8A—C7A—H71A109.4713
N1—C1—H11i109.471C8A—C7A—H72A109.4708
N1i—C1—H11109.471H71A—C7A—H72A111.8888
N1i—C1—H11i109.4714C7A—C8A—C8Aii114.1 (2)
H11—C1—H11i117.1456C7A—C8A—H81A109.4713
N1—C2—C2i100.03 (14)C7A—C8A—H82A109.4714
N1—C2—C3119.23 (12)C8Aii—C8A—H81A109.3716
N1—C2—H2110.0325C8Aii—C8A—H82A110.2434
C2i—C2—C3110.62 (16)H81A—C8A—H82A103.6659
C2i—C2—H2118.7348N4B—N3B—C5B124.2 (3)
C3—C2—H299.3155N4B—N3B—C6B124.2 (3)
C2—C3—C4105.76 (12)C5B—N3B—C6B111.60 (19)
C2—C3—H31109.4713O2B—N4B—N3B113.6 (5)
C2—C3—H32109.4714N3B—C5B—N3Bii100.2 (3)
C4—C3—H31109.4707N3B—C5B—H5B109.4712
C4—C3—H32109.4713N3B—C5B—H5Bii111.4168
H31—C3—H32112.9436N3Bii—C5B—H5B111.4168
C3—C4—C4i113.30 (17)N3Bii—C5B—H5Bii109.4712
C3—C4—H41109.4707H5B—C5B—H5Bii114.0098
C3—C4—H42109.4712N3B—C6B—C6Bii100.5 (2)
C4i—C4—H41109.4717N3B—C6B—C7B120.1 (3)
C4i—C4—H42109.4717N3B—C6B—H6B108.9293
H41—C4—H42105.3534C6Bii—C6B—C7B112.0 (3)
N4A—N3A—C5A124.2 (2)C6Bii—C6B—H6B118.0728
N4A—N3A—C6A124.2 (2)C7B—C6B—H6B98.3341
C5A—N3A—C6A111.60 (15)C6B—C7B—C8B106.9 (3)
O2A—N4A—N3A113.6 (4)C6B—C7B—H71B109.4717
N3A—C5A—N3Aii100.22 (14)C6B—C7B—H72B109.4715
N3A—C5A—H5A109.4712C8B—C7B—H71B109.4713
N3A—C5A—H5Aii111.4168C8B—C7B—H72B109.4708
N3Aii—C5A—H5A111.4168H71B—C7B—H72B111.8888
N3Aii—C5A—H5Aii109.4712C7B—C8B—C8Bii114.1 (3)
H5A—C5A—H5Aii114.0098C7B—C8B—H81B109.4713
N3A—C6A—C6Aii100.50 (18)C7B—C8B—H82B109.4714
N3A—C6A—C7A120.1 (2)C8Bii—C8B—H81B109.3717
N3A—C6A—H6A108.9293C8Bii—C8B—H82B110.2434
C6Aii—C6A—C7A112.0 (2)H81B—C8B—H82B103.6659
Symmetry codes: (i) x+2, y, z+3/2; (ii) x+1, y, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1iii0.962.473.244 (3)137.15
C5B—H5B···O10.962.483.3213 (15)146.93
C6B—H6B···O2Biv0.962.383.111 (4)132.53
Symmetry codes: (iii) x+2, y+1, z+1; (iv) x+1, y+1, z.

Experimental details

Crystal data
Chemical formulaC7H12N4O2
Mr184.2
Crystal system, space groupMonoclinic, P2/c
Temperature (K)120
a, b, c (Å)10.8128 (8), 8.4293 (4), 10.9321 (9)
β (°) 118.192 (8)
V3)878.20 (12)
Z4
Radiation typeCu Kα
µ (mm1)0.88
Crystal size (mm)0.37 × 0.18 × 0.07
Data collection
DiffractometerAgilent Xcalibur
diffractometer with Atlas (Gemini Ultra Cu) detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.549, 1.000
No. of measured, independent and
observed [I > 3σ(I)] reflections
6725, 1376, 1163
Rint0.024
θmax (°)62.2
(sin θ/λ)max1)0.574
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.115, 1.92
No. of reflections1376
No. of parameters122
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.28, 0.25

Computer programs: CrysAlis PRO (Agilent, 2010), SIR2002 (Burla et al., 2003), JANA2006 (Petříček et al., 2006), DIAMOND (Brandenburg & Putz, 2005).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C2—H2···O1i0.962.473.244 (3)137.15
C5B—H5B···O10.962.483.3213 (15)146.93
C6B—H6B···O2Bii0.962.383.111 (4)132.53
Symmetry codes: (i) x+2, y+1, z+1; (ii) x+1, y+1, z.
Comparison of the experimental and optimized geometric parameters of molecules M1 and M2 (Å, °) top
M1/M2M1M2DFT/631G(dp)HF/631G(dp)
N2—O1/N4—O21.2482 (18)1.266 (3)1.2311.182
N2—N1/N4—N31.3014 (17)1.299 (5)1.3271.304
N1—C1/N3—C51.4583 (13)1.462 (2)1.4681.459
N1—C2/N3—C61.4746 (18)1.465 (3)1.4631.455
C2—C3/C6—C71.513 (2)1.505 (4)1.5211.517
C2—C2ii/C6—C6i1.510 (3)1.507 (4)1.5331.517
C3—C4/C7—C81.534 (2)1.528 (4)1.5471.541
C4—C4ii/C8—C8i1.522 (3)1.535 (4)1.5461.540
O1—N2—N1/O2—N4—N3113.73 (12)113.6 (4)113.85115.27
N2—N1—C1/N4—N3—C5124.21 (10)124.2 (2)124.23122.14
N2—N1—C2/N4—N3—C6124.42 (12)124.2 (2)123.99120.97
C1—N1—C2/C5—N3—C6111.35 (9)111.60 (15)111.78111.28
C3—C2—C2ii/C7—C6—C6i110.62 (16)112.0 (2)110.84110.72
C2—C3—C4/C6—C7—C8105.76 (12)106.9 (3)106.64106.80
C3—C4—C4ii/C7—C8—C8i113.30 (17)114.1 (2)113.77113.55
Symmetry codes: (i) -x + 2, y, -z + 3/2; (ii) -x + 1, y, -z + 1/2.
 

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