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Acta Cryst. (2007). E63, o4393    [ doi:10.1107/S1600536807050945 ]

2,8-Dimethoxy-4,10-dimethyl-1,3,7,9-tetranitro-6H,12H-5,11-methanodibenzo[b,f][1,5]diazocine

M. D. H. Bhuiyan, P. Jensen and A. C. Try

Abstract top

In the molecule of the title compound, C19H18N6O10, the 2,8-dimethoxy-4,10-dimethyl-1,3,7,9-tetranitro analogue of Tröger's base, the diazocine bridge imparts a twist such that the two aryl rings are offset with respect to one another. The hinge angle of the molecule, measured as the dihedral angle between the two benzene rings, is 103.64 (5)°.

Comment top

For over 100 years since the first synthesis of Tröger's base it was believed that analogues bearing electron-withdrawing groups could not be prepared in good yields, if at all. This belief was dispelled with the first synthesis of dihalogenated analogues (Jensen & Wärnmark, 2001), tetrabromo (Faroughi et al., 2006) and dinitro analogues (Mederski et al., 2003; Li et al., 2005; Bhuiyan et al., 2007). Compound (I) is the first example of a tetranitro Tröger's base analogue and was prepared in racemic form by reacting 4-methoxy-2-methyl-3,5-dinitroaniline with diglycolic acid in polyphosphoric acid (PPA) as shown in Fig. 2. The molecular structure of (I) is shown in Fig. 1. It is interesting to note that in addition to (I), there are two other reports of simple dibenzo Tröger's base analogues with dihedral angles greater than 100° that bear substituents in the 2,4,8- and 10-positions (Sucholeiki et al., 1988; Faroughi et al., 2006), at the upper end of the the range of 82° (Solano et al., 2005) to 108° (Faroughi et al., 2006), that are the lower and upper limits, respectively, that have been measured for for over twenty simple dibenzo Tröger's base analogues. These results would tend to suggest that the placement of substituents in these positions may lead to an increase in the cavity size of the Tröger's base systems, at least in the crystalline state.

Although the compound was prepared in racemic form, the crystal chosen for analysis crystallized in enantiopure form, however the absolute configuration of the structure has not been established by X-ray methods. This appears to be the fourth example of conglomerate crystallization among Tröger's base systems (Kostyanovsky et al., 2003; Sergeyev et al., 2005; Lenev et al., 2006).

We were interested in preparing a range of nitro-substituted Tröger's base compounds as precursors for supramolecular recognition elements.

Related literature top

For related literature on mononitro-substituted Tröger's base analogues, see: Webb & Wilcox (1990); Pardo et al., (1996). For dinitro-substituted Tröger's base analogues, see: Mederski et al. (2003); Li et al. (2005); Bhuiyan et al. (2007).

For related literature, see: Faroughi et al. (2006); Jensen & Wärnmark (2001); Kostyanovsky et al. (2003); Lenev et al. (2006); Mederski et al. (2003); Sergeyev et al. (2005); Solano et al. (2005); Sucholeiki et al. (1988).

Experimental top

Synthetic details will be reported elsewhere. Crystals of (I) were obtained by slow evaporation of a dichloromethane solution.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2003); software used to prepare material for publication: modiCIFer (Guzei, 2005).

Figures top
[Figure 1]
[Figure 2]
Fig. 1. The molecular structure of (I), with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
2,8-Dimethoxy-4,10-dimethyl-1,3,7,9-tetranitro-6H,12H- 5,11-methanodibenzo[b,f][1,5]diazocine top
Crystal data top
C19H18N6O10Dx = 1.557 Mg m−3
Mr = 490.39Melting point: 509 K
Orthorhombic, P212121Mo Kα radiation
λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 6736 reflections
a = 8.629 (2) Åθ = 2.4–28.3º
b = 9.155 (2) ŵ = 0.13 mm−1
c = 26.484 (5) ÅT = 150 (2) K
V = 2092.2 (8) Å3Plate, pale yellow
Z = 40.50 × 0.47 × 0.20 mm
F000 = 1016
Data collection top
Bruker CCD-1000 area-detector
diffractometer		2951 independent reflections
Radiation source: fine-focus sealed tube2796 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.024
T = 150(2) Kθmax = 28.4º
ω scansθmin = 1.5º
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −11→11
Tmin = 0.913, Tmax = 0.975k = −12→11
20912 measured reflectionsl = −35→35
Refinement top
Refinement on F2H-atom parameters constrained
Least-squares matrix: full  w = 1/[σ2(Fo2) + (0.0569P)2 + 0.4264P]
where P = (Fo2 + 2Fc2)/3
R[F2 > 2σ(F2)] = 0.031(Δ/σ)max < 0.001
wR(F2) = 0.087Δρmax = 0.33 e Å−3
S = 1.04Δρmin = −0.25 e Å−3
2951 reflectionsExtinction correction: none
320 parameters
Primary atom site location: structure-invariant direct methods
Secondary atom site location: difference Fourier map
Hydrogen site location: inferred from neighbouring sites
Crystal data top
C19H18N6O10V = 2092.2 (8) Å3
Mr = 490.39Z = 4
Orthorhombic, P212121Mo Kα
a = 8.629 (2) ŵ = 0.13 mm−1
b = 9.155 (2) ÅT = 150 (2) K
c = 26.484 (5) Å0.50 × 0.47 × 0.20 mm
Data collection top
Bruker CCD-1000 area-detector
diffractometer		2951 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		2796 reflections with I > 2σ(I)
Tmin = 0.913, Tmax = 0.975Rint = 0.024
20912 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.031Δρmax = 0.33 e Å−3
wR(F2) = 0.087Δρmin = −0.25 e Å−3
S = 1.04Absolute structure: ?
2951 reflectionsFlack parameter: ?
320 parametersRogers parameter: ?
H-atom parameters constrained
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 > 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O1−0.24794 (17)0.33842 (19)0.07709 (8)0.0502 (5)
O2−0.08837 (18)0.48777 (15)0.04288 (6)0.0389 (4)
O3−0.16534 (14)0.11061 (15)0.01060 (4)0.0271 (3)
O40.0242 (2)−0.11653 (17)−0.02943 (5)0.0412 (4)
O50.0452 (3)−0.23330 (16)0.04133 (7)0.0519 (4)
O6−0.03451 (19)0.5055 (2)0.31937 (6)0.0516 (5)
O70.1945 (2)0.5605 (2)0.34557 (6)0.0503 (4)
O80.16799 (16)0.21859 (15)0.34025 (4)0.0293 (3)
O90.42213 (18)−0.03735 (17)0.25715 (6)0.0405 (4)
O100.1932 (2)−0.04848 (15)0.29035 (6)0.0390 (3)
N1−0.12096 (16)0.36974 (16)0.06071 (5)0.0229 (3)
N20.04626 (19)−0.12154 (16)0.01626 (6)0.0293 (3)
N30.30705 (16)0.42473 (15)0.14649 (5)0.0204 (3)
N40.38756 (16)0.18709 (16)0.11780 (5)0.0205 (3)
N50.10563 (19)0.49762 (18)0.31727 (5)0.0289 (3)
N60.29756 (19)0.01726 (17)0.26895 (5)0.0267 (3)
C1−0.00005 (17)0.25689 (17)0.06230 (6)0.0192 (3)
C2−0.03352 (19)0.12601 (18)0.03837 (6)0.0210 (3)
C3−0.2842 (2)0.0221 (3)0.03419 (7)0.0362 (4)
H3A−0.2384−0.06950.04620.054*
H3B−0.36570.00050.00950.054*
H3C−0.32880.07540.06280.054*
C40.0768 (2)0.01678 (18)0.04267 (6)0.0217 (3)
C50.21390 (19)0.03065 (17)0.06985 (6)0.0202 (3)
C60.3289 (2)−0.09185 (19)0.07389 (7)0.0274 (3)
H6A0.2939−0.16170.09950.041*
H6B0.4302−0.05250.08360.041*
H6C0.3376−0.14140.04120.041*
C70.24331 (18)0.16794 (17)0.09196 (5)0.0180 (3)
C80.13757 (18)0.28300 (17)0.08822 (5)0.0181 (3)
C90.17197 (19)0.43057 (17)0.11245 (6)0.0205 (3)
H9A0.19170.50340.08560.025*
H9B0.08000.46310.13180.025*
C100.42902 (19)0.34144 (19)0.12147 (6)0.0232 (3)
H10A0.52680.35140.14070.028*
H10B0.44630.38130.08720.028*
C110.38882 (19)0.12370 (18)0.16884 (6)0.0217 (3)
H11A0.49750.10730.17940.026*
H11B0.33610.02770.16800.026*
C120.30895 (18)0.22120 (17)0.20748 (6)0.0199 (3)
C130.27142 (18)0.36599 (17)0.19513 (6)0.0189 (3)
C140.20377 (19)0.46122 (18)0.23053 (6)0.0204 (3)
C150.1778 (2)0.61959 (19)0.21860 (6)0.0273 (3)
H15A0.08930.62920.19570.041*
H15B0.27070.65990.20250.041*
H15C0.15660.67320.24990.041*
C160.17340 (19)0.40371 (19)0.27790 (6)0.0221 (3)
C170.20533 (19)0.26139 (18)0.29235 (6)0.0223 (3)
C180.2990 (3)0.1949 (2)0.37300 (6)0.0335 (4)
H18A0.36330.11590.35940.050*
H18B0.26230.16790.40680.050*
H18C0.36050.28470.37510.050*
C190.27199 (19)0.17181 (18)0.25601 (6)0.0216 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0255 (7)0.0472 (9)0.0781 (12)0.0093 (7)0.0215 (7)0.0217 (9)
O20.0358 (7)0.0257 (6)0.0553 (9)0.0065 (6)0.0150 (7)0.0123 (6)
O30.0214 (5)0.0388 (7)0.0213 (5)−0.0075 (5)−0.0039 (4)0.0033 (5)
O40.0496 (8)0.0450 (8)0.0290 (6)−0.0131 (8)0.0026 (6)−0.0152 (6)
O50.0773 (12)0.0237 (6)0.0548 (9)−0.0119 (8)−0.0092 (10)−0.0007 (6)
O60.0351 (8)0.0801 (13)0.0394 (8)0.0226 (9)0.0029 (7)−0.0153 (9)
O70.0524 (9)0.0621 (10)0.0363 (7)−0.0002 (9)−0.0028 (7)−0.0274 (7)
O80.0311 (7)0.0394 (7)0.0174 (5)0.0006 (6)−0.0004 (5)0.0032 (5)
O90.0401 (8)0.0389 (7)0.0426 (8)0.0175 (7)−0.0053 (6)0.0050 (7)
O100.0501 (9)0.0298 (7)0.0371 (7)−0.0035 (7)0.0030 (7)0.0049 (6)
N10.0191 (6)0.0267 (7)0.0229 (6)0.0022 (6)0.0006 (5)0.0020 (5)
N20.0309 (7)0.0242 (7)0.0329 (7)−0.0076 (6)0.0027 (6)−0.0084 (6)
N30.0205 (6)0.0222 (6)0.0187 (6)−0.0035 (5)0.0011 (5)−0.0020 (5)
N40.0160 (6)0.0244 (6)0.0211 (6)0.0001 (5)−0.0001 (5)−0.0031 (5)
N50.0331 (8)0.0341 (8)0.0196 (6)0.0090 (7)0.0013 (6)−0.0031 (6)
N60.0333 (8)0.0261 (7)0.0209 (6)0.0035 (6)−0.0078 (6)0.0011 (5)
C10.0176 (7)0.0212 (7)0.0187 (6)0.0011 (6)0.0023 (5)0.0020 (5)
C20.0201 (7)0.0260 (7)0.0167 (6)−0.0049 (6)0.0004 (6)0.0008 (6)
C30.0268 (9)0.0514 (12)0.0302 (9)−0.0165 (9)−0.0057 (7)0.0059 (9)
C40.0245 (8)0.0199 (7)0.0207 (7)−0.0043 (6)0.0026 (6)−0.0032 (6)
C50.0213 (7)0.0200 (7)0.0192 (6)0.0005 (6)0.0038 (6)−0.0011 (6)
C60.0284 (8)0.0227 (7)0.0310 (8)0.0053 (7)0.0030 (7)−0.0027 (6)
C70.0173 (7)0.0206 (7)0.0163 (6)−0.0006 (6)0.0025 (5)−0.0017 (5)
C80.0184 (7)0.0202 (7)0.0157 (6)−0.0026 (6)0.0036 (5)−0.0007 (5)
C90.0232 (7)0.0193 (7)0.0189 (6)−0.0003 (6)0.0005 (6)−0.0004 (5)
C100.0182 (7)0.0290 (8)0.0226 (7)−0.0057 (6)0.0027 (6)−0.0046 (6)
C110.0192 (7)0.0251 (7)0.0209 (7)0.0048 (6)−0.0011 (6)−0.0027 (6)
C120.0170 (6)0.0230 (7)0.0198 (6)0.0008 (6)−0.0017 (6)−0.0023 (6)
C130.0165 (6)0.0217 (7)0.0185 (6)−0.0026 (6)−0.0011 (5)−0.0021 (5)
C140.0185 (7)0.0222 (7)0.0204 (7)−0.0006 (6)−0.0016 (6)−0.0032 (6)
C150.0355 (9)0.0218 (7)0.0245 (7)0.0031 (7)0.0004 (7)−0.0027 (6)
C160.0201 (7)0.0282 (8)0.0180 (7)0.0024 (6)−0.0014 (6)−0.0053 (6)
C170.0212 (7)0.0288 (8)0.0168 (6)0.0001 (7)−0.0021 (6)0.0000 (6)
C180.0414 (10)0.0366 (10)0.0227 (8)0.0015 (9)−0.0101 (7)0.0019 (7)
C190.0207 (7)0.0240 (7)0.0201 (7)0.0011 (6)−0.0039 (6)0.0004 (6)
Geometric parameters (Å, °) top
O1—N11.213 (2)C4—C51.391 (2)
O2—N11.212 (2)C5—C71.410 (2)
O3—C21.3618 (19)C5—C61.501 (2)
O3—C31.449 (2)C6—H6A0.9800
O4—N21.226 (2)C6—H6B0.9800
O5—N21.220 (2)C6—H6C0.9800
O6—N51.213 (2)C7—C81.397 (2)
O7—N51.217 (2)C8—C91.525 (2)
O8—C171.366 (2)C9—H9A0.9900
O8—C181.441 (2)C9—H9B0.9900
O9—N61.226 (2)C10—H10A0.9900
O10—N61.223 (2)C10—H10B0.9900
N1—C11.469 (2)C11—C121.523 (2)
N2—C41.470 (2)C11—H11A0.9900
N3—C131.4295 (19)C11—H11B0.9900
N3—C101.459 (2)C12—C191.399 (2)
N3—C91.475 (2)C12—C131.403 (2)
N4—C71.431 (2)C13—C141.407 (2)
N4—C101.461 (2)C14—C161.386 (2)
N4—C111.471 (2)C14—C151.501 (2)
N5—C161.472 (2)C15—H15A0.9800
N6—C191.473 (2)C15—H15B0.9800
C1—C21.386 (2)C15—H15C0.9800
C1—C81.392 (2)C16—C171.386 (2)
C2—C41.385 (2)C17—C191.389 (2)
C3—H3A0.9800C18—H18A0.9800
C3—H3B0.9800C18—H18B0.9800
C3—H3C0.9800C18—H18C0.9800
C2—O3—C3114.59 (13)C7—C8—C9120.73 (14)
C17—O8—C18114.64 (14)N3—C9—C8112.28 (13)
O2—N1—O1124.03 (16)N3—C9—H9A109.1
O2—N1—C1118.24 (14)C8—C9—H9A109.1
O1—N1—C1117.72 (14)N3—C9—H9B109.1
O5—N2—O4124.57 (16)C8—C9—H9B109.1
O5—N2—C4117.72 (15)H9A—C9—H9B107.9
O4—N2—C4117.71 (15)N3—C10—N4111.05 (13)
C13—N3—C10111.58 (13)N3—C10—H10A109.4
C13—N3—C9113.24 (12)N4—C10—H10A109.4
C10—N3—C9108.16 (12)N3—C10—H10B109.4
C7—N4—C10111.31 (13)N4—C10—H10B109.4
C7—N4—C11113.42 (13)H10A—C10—H10B108.0
C10—N4—C11108.57 (13)N4—C11—C12112.52 (13)
O6—N5—O7124.88 (18)N4—C11—H11A109.1
O6—N5—C16117.60 (17)C12—C11—H11A109.1
O7—N5—C16117.52 (16)N4—C11—H11B109.1
O10—N6—O9124.29 (16)C12—C11—H11B109.1
O10—N6—C19118.07 (16)H11A—C11—H11B107.8
O9—N6—C19117.63 (16)C19—C12—C13117.83 (15)
C2—C1—C8123.48 (15)C19—C12—C11122.07 (15)
C2—C1—N1116.55 (14)C13—C12—C11120.10 (14)
C8—C1—N1119.94 (14)C12—C13—C14121.72 (14)
O3—C2—C4122.92 (15)C12—C13—N3121.06 (14)
O3—C2—C1120.70 (15)C14—C13—N3117.17 (14)
C4—C2—C1116.32 (15)C16—C14—C13116.51 (15)
O3—C3—H3A109.5C16—C14—C15121.97 (15)
O3—C3—H3B109.5C13—C14—C15121.35 (15)
H3A—C3—H3B109.5C14—C15—H15A109.5
O3—C3—H3C109.5C14—C15—H15B109.5
H3A—C3—H3C109.5H15A—C15—H15B109.5
H3B—C3—H3C109.5C14—C15—H15C109.5
C2—C4—C5124.14 (15)H15A—C15—H15C109.5
C2—C4—N2117.37 (15)H15B—C15—H15C109.5
C5—C4—N2118.49 (15)C14—C16—C17124.73 (15)
C4—C5—C7116.71 (14)C14—C16—N5119.63 (15)
C4—C5—C6122.07 (15)C17—C16—N5115.62 (14)
C7—C5—C6121.17 (15)O8—C17—C16118.64 (15)
C5—C6—H6A109.5O8—C17—C19124.86 (16)
C5—C6—H6B109.5C16—C17—C19116.49 (15)
H6A—C6—H6B109.5O8—C18—H18A109.5
C5—C6—H6C109.5O8—C18—H18B109.5
H6A—C6—H6C109.5H18A—C18—H18B109.5
H6B—C6—H6C109.5O8—C18—H18C109.5
C8—C7—C5121.68 (14)H18A—C18—H18C109.5
C8—C7—N4120.63 (14)H18B—C18—H18C109.5
C5—C7—N4117.67 (14)C17—C19—C12122.68 (15)
C1—C8—C7117.55 (14)C17—C19—N6117.90 (15)
C1—C8—C9121.71 (14)C12—C19—N6119.36 (15)
O2—N1—C1—C2−123.01 (17)C7—N4—C10—N356.74 (17)
O1—N1—C1—C256.5 (2)C11—N4—C10—N3−68.78 (16)
O2—N1—C1—C858.8 (2)C7—N4—C11—C12−79.62 (16)
O1—N1—C1—C8−121.7 (2)C10—N4—C11—C1244.66 (17)
C3—O3—C2—C476.4 (2)N4—C11—C12—C19168.27 (14)
C3—O3—C2—C1−106.45 (19)N4—C11—C12—C13−12.4 (2)
C8—C1—C2—O3−175.31 (14)C19—C12—C13—C142.2 (2)
N1—C1—C2—O36.6 (2)C11—C12—C13—C14−177.18 (14)
C8—C1—C2—C42.0 (2)C19—C12—C13—N3179.33 (14)
N1—C1—C2—C4−176.08 (13)C11—C12—C13—N30.0 (2)
O3—C2—C4—C5178.54 (15)C10—N3—C13—C12−20.9 (2)
C1—C2—C4—C51.3 (2)C9—N3—C13—C12101.40 (17)
O3—C2—C4—N2−0.9 (2)C10—N3—C13—C14156.36 (14)
C1—C2—C4—N2−178.10 (14)C9—N3—C13—C14−81.33 (17)
O5—N2—C4—C2−123.3 (2)C12—C13—C14—C16−1.2 (2)
O4—N2—C4—C257.0 (2)N3—C13—C14—C16−178.47 (14)
O5—N2—C4—C557.3 (2)C12—C13—C14—C15174.14 (15)
O4—N2—C4—C5−122.48 (18)N3—C13—C14—C15−3.1 (2)
C2—C4—C5—C7−3.3 (2)C13—C14—C16—C170.2 (2)
N2—C4—C5—C7176.13 (14)C15—C14—C16—C17−175.08 (16)
C2—C4—C5—C6179.20 (15)C13—C14—C16—N5178.75 (15)
N2—C4—C5—C6−1.4 (2)C15—C14—C16—N53.4 (3)
C4—C5—C7—C82.1 (2)O6—N5—C16—C1488.4 (2)
C6—C5—C7—C8179.65 (14)O7—N5—C16—C14−92.3 (2)
C4—C5—C7—N4−176.71 (14)O6—N5—C16—C17−93.0 (2)
C6—C5—C7—N40.9 (2)O7—N5—C16—C1786.4 (2)
C10—N4—C7—C8−20.73 (19)C18—O8—C17—C16−109.32 (18)
C11—N4—C7—C8102.05 (17)C18—O8—C17—C1971.6 (2)
C10—N4—C7—C5158.08 (14)C14—C16—C17—O8−179.42 (15)
C11—N4—C7—C5−79.14 (16)N5—C16—C17—O82.0 (2)
C2—C1—C8—C7−3.0 (2)C14—C16—C17—C19−0.3 (2)
N1—C1—C8—C7174.98 (13)N5—C16—C17—C19−178.84 (15)
C2—C1—C8—C9177.82 (14)O8—C17—C19—C12−179.61 (15)
N1—C1—C8—C9−4.1 (2)C16—C17—C19—C121.3 (2)
C5—C7—C8—C10.9 (2)O8—C17—C19—N63.2 (2)
N4—C7—C8—C1179.63 (13)C16—C17—C19—N6−175.87 (15)
C5—C7—C8—C9−179.99 (13)C13—C12—C19—C17−2.3 (2)
N4—C7—C8—C9−1.2 (2)C11—C12—C19—C17177.10 (15)
C13—N3—C9—C8−80.15 (16)C13—C12—C19—N6174.90 (14)
C10—N3—C9—C844.05 (17)C11—C12—C19—N6−5.7 (2)
C1—C8—C9—N3168.06 (13)O10—N6—C19—C1744.5 (2)
C7—C8—C9—N3−11.0 (2)O9—N6—C19—C17−136.02 (17)
C13—N3—C10—N455.74 (17)O10—N6—C19—C12−132.75 (17)
C9—N3—C10—N4−69.45 (17)O9—N6—C19—C1246.7 (2)
Acknowledgements top

The authors thank the Australian Research Council for a Discovery Project grant (No. DP0345180) to ACT, and Macquarie University for the award of a Macquarie University Research Development grant to ACT and the award of an iMURS grant to MDHB.

references
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