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Acta Cryst. (2007). E63, o3374    [ doi:10.1107/S1600536807031819 ]

Diethyl 2,6-diethyl-4,8-dioxo-2,3,6,7-tetrahydro-1H,5H-2,3a,4a,6,7a,8a-hexaazacyclopenta[def]fluorene-8b,8c-dicarboxylate

L.-P. Cao, Y.-Z. Wang and M. Gao

Abstract top

The title compound, C18H28N6O6, is a derivative of glycoluril, with two ethyl acetate substituents on the convex face of the glycoluril system. Two equivalent six-membered rings bind the N atoms from separate rings of the glycoluril unit to form the flexible sidewalls of a molecular clip. One N atom from each ring carries an ethyl substituent. The crystal packing is stabilized by non-classical C-H...O hydrogen bonds.

Comment top

In 1905, Behrend reported that the condensation of glycoluril and formadehyde in dilute HCl yielded an insoluble polymeric material now known as Behrend's polymer (Behrend et al., 1905). After 76 years, the molecular structure (obtained by heating Behrend's polymer in H2SO4) was disclosed by Mock and co-workers who named it cucurbituril (Freeman et al., 1981). Glycoluril and its derivatives have during the past two decades established an impressive career as building block for supramolecular chemistry (Freeman et al., 1981; Rebek, 2005; Rowan et al., 1999; Wu et al., 2002). As a part of our ongoing investigation into glycoluril derivatives (Li et al., 2006), we report here the structure of the title compound (I) (Fig. 1).

The molecular structure of (I) is shown in Fig. 1. It has four fused rings - two imidazole and two triazinane rings, respectively. The crystal packing is stabilized by intermolecular non-classical C—H···O hydrogen bonds (Table 1).

Related literature top

For preparation of the title compound, see: Li et al. (2006). For general background regarding glycoluril and its derivatives, see: Behrend et al. (1905); Freeman et al. (1981); Rebek (2005); Rowan et al. (1999); Wu et al. (2002).

Experimental top

The title compound was synthesized according to the procedure of Li et al. (2006) in 10% isolated yield. Crystals of (I) suitable for X-ray data collection were obtained by slow evaporation of a chloroform and methaol solution in ratio of 20:1 at 293 K.

Refinement top

All H atoms were positioned geometrically (C—H = 0.96–0.97 Å) and refined using a riding model, with Uiso(H) = 1.2Ueq(C) (1.5Ueq(C) for methly) of the parent atoms.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: PLATON.

Figures top
[Figure 1] Fig. 1. View of the molecule of (I) showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented by spheres of arbitrary radius.
Diethyl 2,6-diethyl-4,8-dioxo-2,3,6,7-tetrahydro-1H,5H-2,3a,4a,6,7a,8a-\ hexaazacyclopenta[def]fluorene-8 b,8c-dicarboxylate top
Crystal data top
C18H28N6O6F(000) = 1808
Mr = 424.47Dx = 1.352 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3350 reflections
a = 20.3689 (13) Åθ = 2.5–22.8°
b = 7.8804 (5) ŵ = 0.10 mm−1
c = 25.9921 (16) ÅT = 292 K
β = 91.697 (1)°Block, colourless
V = 4170.3 (5) Å30.30 × 0.20 × 0.20 mm
Z = 8
Data collection top
Bruker SMART 4K CCD area-detector
diffractometer		2901 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.031
graphiteθmax = 25.0°, θmin = 2.0°
φ and ω scansh = −24→20
13315 measured reflectionsk = −9→9
3662 independent reflectionsl = −30→30
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)] = 0.068Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.190H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0969P)2 + 6.5727P]
where P = (Fo2 + 2Fc2)/3
3662 reflections(Δ/σ)max < 0.001
275 parametersΔρmax = 0.76 e Å−3
0 restraintsΔρmin = −0.50 e Å−3
Crystal data top
C18H28N6O6V = 4170.3 (5) Å3
Mr = 424.47Z = 8
Monoclinic, C2/cMo Kα radiation
a = 20.3689 (13) ŵ = 0.10 mm−1
b = 7.8804 (5) ÅT = 292 K
c = 25.9921 (16) Å0.30 × 0.20 × 0.20 mm
β = 91.697 (1)°
Data collection top
Bruker SMART 4K CCD area-detector
diffractometer		2901 reflections with I > 2σ(I)
13315 measured reflectionsRint = 0.031
3662 independent reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.068H-atom parameters constrained
wR(F2) = 0.190Δρmax = 0.76 e Å−3
S = 1.04Δρmin = −0.50 e Å−3
3662 reflectionsAbsolute structure: ?
275 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
C10.5192 (2)0.4727 (9)0.3310 (2)0.115 (2)
H1A0.51980.39430.30270.172*
H1B0.55290.44270.35590.172*
H1C0.52700.58550.31860.172*
C20.45446 (17)0.4660 (5)0.35513 (14)0.0613 (9)
H2A0.45090.35990.37380.074*
H2B0.45170.55780.37990.074*
C30.39338 (16)0.6401 (4)0.29128 (11)0.0521 (8)
H3A0.36680.62430.26010.062*
H3B0.43680.67580.28130.062*
C40.33661 (15)0.4321 (4)0.33911 (11)0.0459 (7)
H4A0.34290.33210.36050.055*
H4B0.30630.40230.31110.055*
C50.39979 (14)0.8907 (4)0.35146 (11)0.0429 (7)
C60.31809 (13)0.5820 (3)0.42271 (10)0.0374 (6)
C70.30321 (13)0.7315 (3)0.34576 (10)0.0344 (6)
C80.24532 (14)0.7504 (4)0.30633 (11)0.0417 (7)
C90.14594 (14)0.6412 (4)0.27281 (13)0.0526 (8)
H9A0.15840.60890.23840.063*
H9B0.12960.75690.27160.063*
C100.09497 (19)0.5268 (6)0.29102 (18)0.0849 (13)
H10A0.11200.41340.29320.127*
H10B0.05790.52920.26740.127*
H10C0.08160.56290.32440.127*
C110.30001 (13)0.8576 (3)0.39207 (10)0.0363 (6)
C120.23560 (15)0.9608 (4)0.39291 (12)0.0462 (7)
C130.1855 (2)1.2302 (6)0.3808 (2)0.0906 (14)
H13A0.19441.33130.36100.109*
H13B0.14981.16880.36370.109*
C140.1675 (3)1.2762 (8)0.4321 (3)0.128 (2)
H14A0.15011.17870.44910.191*
H14B0.13481.36390.43030.191*
H14C0.20551.31680.45100.191*
C150.38474 (15)1.0349 (4)0.43596 (12)0.0472 (7)
H15A0.42761.08360.42990.057*
H15B0.35591.12640.44590.057*
C160.32934 (15)0.8260 (4)0.48422 (11)0.0470 (7)
H16A0.29690.90550.49630.056*
H16B0.33540.73900.51030.056*
C170.44876 (16)0.8037 (4)0.47574 (13)0.0542 (8)
H17A0.48680.87140.46740.065*
H17B0.44170.72110.44850.065*
C180.4623 (2)0.7123 (5)0.52582 (16)0.0754 (11)
H18A0.46090.79170.55380.113*
H18B0.50500.66080.52530.113*
H18C0.42960.62610.53030.113*
N10.39898 (13)0.4795 (3)0.31793 (9)0.0498 (7)
N20.36403 (11)0.7760 (3)0.32213 (8)0.0406 (6)
N30.30724 (11)0.5667 (3)0.36995 (8)0.0359 (5)
N40.35879 (11)0.9595 (3)0.38760 (9)0.0393 (6)
N50.30415 (11)0.7466 (3)0.43647 (8)0.0372 (5)
N60.39087 (12)0.9148 (3)0.47816 (9)0.0469 (6)
O10.45657 (11)0.9299 (3)0.34542 (9)0.0636 (7)
O20.33390 (12)0.4685 (3)0.45184 (8)0.0536 (6)
O30.24162 (13)0.8728 (4)0.27949 (11)0.0837 (9)
O40.20263 (9)0.6294 (2)0.30835 (7)0.0441 (5)
O50.18423 (11)0.8918 (3)0.39870 (10)0.0624 (7)
O60.24504 (12)1.1218 (3)0.38462 (13)0.0812 (9)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.056 (3)0.201 (6)0.087 (3)0.026 (3)−0.002 (2)0.011 (4)
C20.056 (2)0.072 (2)0.055 (2)0.0107 (17)−0.0103 (16)−0.0021 (17)
C30.0484 (18)0.071 (2)0.0370 (16)0.0034 (15)0.0055 (13)−0.0026 (15)
C40.0529 (18)0.0413 (15)0.0428 (16)0.0034 (13)−0.0097 (14)−0.0052 (13)
C50.0364 (16)0.0516 (17)0.0405 (15)−0.0100 (13)−0.0011 (12)0.0145 (13)
C60.0384 (15)0.0360 (14)0.0377 (15)−0.0082 (12)−0.0034 (12)0.0062 (12)
C70.0345 (14)0.0342 (13)0.0344 (14)−0.0035 (11)−0.0032 (11)0.0034 (11)
C80.0417 (16)0.0445 (16)0.0384 (15)−0.0039 (13)−0.0077 (12)0.0089 (13)
C90.0371 (16)0.0630 (19)0.0566 (19)0.0025 (14)−0.0149 (14)−0.0001 (15)
C100.048 (2)0.103 (3)0.102 (3)−0.021 (2)−0.016 (2)0.015 (3)
C110.0331 (14)0.0333 (13)0.0424 (15)−0.0056 (11)−0.0004 (11)0.0038 (11)
C120.0420 (17)0.0380 (15)0.0581 (19)−0.0074 (13)−0.0053 (14)−0.0002 (13)
C130.080 (3)0.068 (3)0.124 (4)0.010 (2)−0.005 (3)0.018 (3)
C140.127 (5)0.117 (4)0.140 (5)0.008 (4)0.030 (4)−0.047 (4)
C150.0483 (18)0.0383 (15)0.0544 (18)−0.0111 (13)−0.0062 (14)−0.0022 (13)
C160.0562 (19)0.0498 (17)0.0351 (15)−0.0069 (14)0.0009 (13)−0.0058 (13)
C170.0535 (19)0.0525 (18)0.0559 (19)−0.0064 (15)−0.0116 (15)−0.0058 (15)
C180.070 (2)0.074 (2)0.081 (3)−0.010 (2)−0.026 (2)0.017 (2)
N10.0513 (16)0.0541 (15)0.0435 (14)0.0085 (12)−0.0034 (12)−0.0020 (12)
N20.0381 (13)0.0480 (13)0.0356 (12)−0.0042 (10)−0.0001 (10)0.0049 (10)
N30.0406 (13)0.0338 (11)0.0327 (12)−0.0043 (9)−0.0064 (9)0.0023 (9)
N40.0376 (13)0.0367 (12)0.0433 (13)−0.0089 (10)−0.0043 (10)0.0037 (10)
N50.0426 (13)0.0362 (12)0.0330 (12)−0.0069 (10)0.0022 (10)0.0020 (9)
N60.0536 (15)0.0437 (13)0.0428 (14)−0.0072 (12)−0.0069 (11)−0.0048 (11)
O10.0419 (13)0.0848 (17)0.0644 (15)−0.0225 (12)0.0067 (11)0.0081 (12)
O20.0770 (16)0.0419 (11)0.0411 (11)−0.0071 (10)−0.0120 (10)0.0114 (9)
O30.0736 (17)0.0874 (18)0.0875 (19)−0.0298 (14)−0.0399 (15)0.0500 (16)
O40.0349 (11)0.0496 (11)0.0471 (12)−0.0065 (9)−0.0091 (9)0.0052 (9)
O50.0426 (13)0.0577 (14)0.0871 (18)−0.0013 (11)0.0073 (12)0.0011 (12)
O60.0559 (15)0.0467 (14)0.140 (3)0.0042 (11)−0.0048 (16)0.0078 (15)
Geometric parameters (Å, °) top
C1—C21.479 (6)C10—H10A0.9600
C1—H1A0.9600C10—H10B0.9600
C1—H1B0.9600C10—H10C0.9600
C1—H1C0.9600C11—N51.448 (3)
C2—N11.469 (4)C11—N41.449 (3)
C2—H2A0.9700C11—C121.544 (4)
C2—H2B0.9700C12—O51.192 (3)
C3—N11.446 (4)C12—O61.302 (4)
C3—N21.475 (4)C13—C141.438 (7)
C3—H3A0.9700C13—O61.485 (5)
C3—H3B0.9700C13—H13A0.9700
C4—N11.448 (4)C13—H13B0.9700
C4—N31.468 (4)C14—H14A0.9600
C4—H4A0.9700C14—H14B0.9600
C4—H4B0.9700C14—H14C0.9600
C5—O11.212 (3)C15—N61.452 (4)
C5—N21.377 (4)C15—N41.474 (4)
C5—N41.386 (4)C15—H15A0.9700
C6—O21.210 (3)C15—H15B0.9700
C6—N51.377 (3)C16—N61.448 (4)
C6—N31.388 (3)C16—N51.469 (3)
C7—N21.442 (3)C16—H16A0.9700
C7—N31.444 (3)C16—H16B0.9700
C7—C81.547 (4)C17—N61.471 (4)
C7—C111.564 (4)C17—C181.506 (5)
C8—O31.192 (3)C17—H17A0.9700
C8—O41.293 (3)C17—H17B0.9700
C9—O41.460 (3)C18—H18A0.9600
C9—C101.464 (5)C18—H18B0.9600
C9—H9A0.9700C18—H18C0.9600
C9—H9B0.9700
C2—C1—H1A109.5O5—C12—C11120.7 (3)
C2—C1—H1B109.5O6—C12—C11112.4 (3)
H1A—C1—H1B109.5C14—C13—O6108.3 (5)
C2—C1—H1C109.5C14—C13—H13A110.0
H1A—C1—H1C109.5O6—C13—H13A110.0
H1B—C1—H1C109.5C14—C13—H13B110.0
N1—C2—C1113.3 (3)O6—C13—H13B110.0
N1—C2—H2A108.9H13A—C13—H13B108.4
C1—C2—H2A108.9C13—C14—H14A109.5
N1—C2—H2B108.9C13—C14—H14B109.5
C1—C2—H2B108.9H14A—C14—H14B109.5
H2A—C2—H2B107.7C13—C14—H14C109.5
N1—C3—N2113.8 (2)H14A—C14—H14C109.5
N1—C3—H3A108.8H14B—C14—H14C109.5
N2—C3—H3A108.8N6—C15—N4113.7 (2)
N1—C3—H3B108.8N6—C15—H15A108.8
N2—C3—H3B108.8N4—C15—H15A108.8
H3A—C3—H3B107.7N6—C15—H15B108.8
N1—C4—N3113.4 (2)N4—C15—H15B108.8
N1—C4—H4A108.9H15A—C15—H15B107.7
N3—C4—H4A108.9N6—C16—N5113.3 (2)
N1—C4—H4B108.9N6—C16—H16A108.9
N3—C4—H4B108.9N5—C16—H16A108.9
H4A—C4—H4B107.7N6—C16—H16B108.9
O1—C5—N2125.9 (3)N5—C16—H16B108.9
O1—C5—N4125.8 (3)H16A—C16—H16B107.7
N2—C5—N4108.2 (2)N6—C17—C18111.9 (3)
O2—C6—N5125.9 (3)N6—C17—H17A109.2
O2—C6—N3125.9 (3)C18—C17—H17A109.2
N5—C6—N3108.1 (2)N6—C17—H17B109.2
N2—C7—N3111.5 (2)C18—C17—H17B109.2
N2—C7—C8110.0 (2)H17A—C17—H17B107.9
N3—C7—C8114.1 (2)C17—C18—H18A109.5
N2—C7—C11103.2 (2)C17—C18—H18B109.5
N3—C7—C11103.9 (2)H18A—C18—H18B109.5
C8—C7—C11113.6 (2)C17—C18—H18C109.5
O3—C8—O4126.2 (3)H18A—C18—H18C109.5
O3—C8—C7120.0 (3)H18B—C18—H18C109.5
O4—C8—C7113.7 (2)C3—N1—C4110.5 (2)
O4—C9—C10108.1 (3)C3—N1—C2115.3 (3)
O4—C9—H9A110.1C4—N1—C2113.4 (3)
C10—C9—H9A110.1C5—N2—C7111.8 (2)
O4—C9—H9B110.1C5—N2—C3124.1 (2)
C10—C9—H9B110.1C7—N2—C3114.9 (2)
H9A—C9—H9B108.4C6—N3—C7110.9 (2)
C9—C10—H10A109.5C6—N3—C4123.2 (2)
C9—C10—H10B109.5C7—N3—C4115.5 (2)
H10A—C10—H10B109.5C5—N4—C11110.7 (2)
C9—C10—H10C109.5C5—N4—C15121.9 (2)
H10A—C10—H10C109.5C11—N4—C15115.6 (2)
H10B—C10—H10C109.5C6—N5—C11111.7 (2)
N5—C11—N4111.7 (2)C6—N5—C16123.5 (2)
N5—C11—C12109.6 (2)C11—N5—C16115.2 (2)
N4—C11—C12114.4 (2)C16—N6—C15110.0 (2)
N5—C11—C7103.1 (2)C16—N6—C17114.5 (2)
N4—C11—C7103.7 (2)C15—N6—C17114.0 (3)
C12—C11—C7113.6 (2)C8—O4—C9116.6 (2)
O5—C12—O6126.8 (3)C12—O6—C13116.6 (3)
N2—C7—C8—O3−44.8 (4)C8—C7—N3—C6−134.4 (2)
N3—C7—C8—O3−170.9 (3)C11—C7—N3—C6−10.2 (3)
C11—C7—C8—O370.3 (4)N2—C7—N3—C4−46.0 (3)
N2—C7—C8—O4138.7 (2)C8—C7—N3—C479.3 (3)
N3—C7—C8—O412.6 (3)C11—C7—N3—C4−156.5 (2)
C11—C7—C8—O4−106.1 (3)N1—C4—N3—C6−91.5 (3)
N2—C7—C11—N5−115.2 (2)N1—C4—N3—C750.3 (3)
N3—C7—C11—N51.2 (2)O1—C5—N4—C11−166.8 (3)
C8—C7—C11—N5125.7 (2)N2—C5—N4—C1115.9 (3)
N2—C7—C11—N41.4 (2)O1—C5—N4—C15−25.8 (4)
N3—C7—C11—N4117.8 (2)N2—C5—N4—C15156.9 (2)
C8—C7—C11—N4−117.7 (2)N5—C11—N4—C5100.0 (3)
N2—C7—C11—C12126.2 (2)C12—C11—N4—C5−134.7 (2)
N3—C7—C11—C12−117.4 (2)C7—C11—N4—C5−10.4 (3)
C8—C7—C11—C127.1 (3)N5—C11—N4—C15−43.7 (3)
N5—C11—C12—O5−50.3 (4)C12—C11—N4—C1581.6 (3)
N4—C11—C12—O5−176.7 (3)C7—C11—N4—C15−154.1 (2)
C7—C11—C12—O564.4 (4)N6—C15—N4—C5−90.4 (3)
N5—C11—C12—O6132.3 (3)N6—C15—N4—C1149.0 (3)
N4—C11—C12—O66.0 (4)O2—C6—N5—C11168.3 (3)
C7—C11—C12—O6−112.9 (3)N3—C6—N5—C11−15.0 (3)
N2—C3—N1—C451.4 (3)O2—C6—N5—C1624.0 (4)
N2—C3—N1—C2−78.8 (3)N3—C6—N5—C16−159.4 (2)
N3—C4—N1—C3−51.2 (3)N4—C11—N5—C6−102.5 (3)
N3—C4—N1—C279.9 (3)C12—C11—N5—C6129.5 (2)
C1—C2—N1—C3−65.4 (5)C7—C11—N5—C68.2 (3)
C1—C2—N1—C4165.8 (4)N4—C11—N5—C1644.9 (3)
O1—C5—N2—C7167.7 (3)C12—C11—N5—C16−83.0 (3)
N4—C5—N2—C7−15.1 (3)C7—C11—N5—C16155.7 (2)
O1—C5—N2—C322.6 (4)N6—C16—N5—C691.7 (3)
N4—C5—N2—C3−160.1 (2)N6—C16—N5—C11−51.5 (3)
N3—C7—N2—C5−102.8 (3)N5—C16—N6—C1553.3 (3)
C8—C7—N2—C5129.7 (2)N5—C16—N6—C17−76.6 (3)
C11—C7—N2—C58.1 (3)N4—C15—N6—C16−52.1 (3)
N3—C7—N2—C345.7 (3)N4—C15—N6—C1778.1 (3)
C8—C7—N2—C3−81.9 (3)C18—C17—N6—C16−66.0 (3)
C11—C7—N2—C3156.6 (2)C18—C17—N6—C15166.1 (3)
N1—C3—N2—C593.8 (3)O3—C8—O4—C92.6 (5)
N1—C3—N2—C7−50.3 (3)C7—C8—O4—C9178.8 (2)
O2—C6—N3—C7−167.5 (3)C10—C9—O4—C8−162.9 (3)
N5—C6—N3—C715.8 (3)O5—C12—O6—C13−1.5 (6)
O2—C6—N3—C4−24.3 (4)C11—C12—O6—C13175.7 (3)
N5—C6—N3—C4159.1 (2)C14—C13—O6—C1283.9 (5)
N2—C7—N3—C6100.3 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C4—H4B···O3i0.972.533.460 (4)160
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C4—H4B···O3i0.972.533.460 (4)160
Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2.
Acknowledgements top

The authors thank Professor An-Xin Wu (Central China Normal University, Wuhan, China) for helpful discussions, and Dr Xiang-Gao Meng for the X-ray data collection.

references
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