organic compounds
Hexacyclo[6.5.1.01,5.05,12.07,11.09,13]tetradecane-4,6,14-trione
aDepartment of Chemistry, Indian Institute of Technology - Bombay, Powai, Mumbai 400 076, India
*Correspondence e-mail: srk@chem.iitb.ac.in
The structure of the title 14H12O3, encompasses seven fused rings, viz. one four-membered, five five-membered and one six-membered. The four-membered ring is essentially planar, all five-membered rings adopt an and the six-membered ring adopts a boat conformation.
CKeywords: crystal structure; cage compound; hexacyclic trione; cycloaddition.
CCDC reference: 1842060
Structure description
As a result of their rigid and strained architectures, polycyclic cage molecules act as a useful scaffold for pharmaceutical applications (Liu et al., 2001; Wilkinson et al., 2014), medicinal chemistry (Wanka et al., 2013; Liu et al., 2011) and energetic materials (Wu et al., 2015; Lal et al., 2014). Some of the oxa-cage systems play an important role in molecular recognition and inclusion phenomena (Marchand et al., 1998). Cage hydrocarbons are useful as core frameworks for photonic/electronic materials (Giacalone & Martín, 2006; Lebedeva et al., 2015) and ligands for organocatalysis (Biegasiewicz et al., 2012).
In view of our research interest in designing various new cage compounds, herein we report the structure and synthesis of the title compound (Fig. 1). The title compound (II) was synthesized (Fig. 2) from inexpensive and commercially available starting materials such as 2,5-dimethoxy benzaldehyde using the Diels–Alder reaction as a key step (Kotha et al., 2017).
The molecular structure of (II) is built up of seven rings: one four-membered, five five-membered and one six-membered rings are fused to a caged carbon framework. The four-membered ring is essentially planar. All five-membered rings adopt an
whereas the six-membered ring is in a boat conformation.Synthesis and crystallization
The title via a Diels–Alder reaction of cyclopentadiene with 2,3-dihydro-1H-indene-1,4,7-trione followed by [2 + 2] photocycloaddition. To begin with, Diels–Alder adduct (I) (100 mg, 0.43 mmol) was dissolved in dry ethyl acetate (300 ml) and irradiated in a Pyrex immersion well by using 125 W medium pressure UV mercury vapour lamp for 1 h under nitrogen at room temperature. After completion of the reaction (TLC monitoring), the solvent was evaporated under reduced pressure and the crude reaction mixture was purified by silica-gel using 40% ethyl acetate in petroleum ether as an to furnish (II) as a colourless crystalline solid (92 mg, 94%). Recrystallization of a [2 + 2] photocycloadduct from a 1:4 mixture of dichloromethane–hexane solvent system delivered orthorhombic crystals of hexacyclic trione (II), m.p. 452–454 K (the melting point was recorded on a veego VMP–CMP melting point apparatus and is uncorrected). IR (neat, cm−1) 2976, 1757, 1740, 1434, 1266, 1139. 1H NMR (500 MHz, CDCl3, p.p.m.): 3.19 (t, J = 6.2 Hz, 1H), 3.05–3.02 (m, 3H), 2.80–2.74 (m, 2H), 2.69–2.60 (m, 1H), 2.53–2.40 (m, 2H), 2.08 (d, J = 11.5 Hz, 1H), 1.93 (d, J = 11.4 Hz, 1H), 1.89–1.84 (m, 1H). 13C NMR (125 MHz, CDCl3, p.p.m.): 210.7, 209.3, 205.2, 60.0, 56.6, 56.0, 54.7, 43.9, 43.6, 43.3, 42.8, 40.0, 39.9, 20.4; HRMS (ESI, Q-TOF) m/z calculated for C14H13O3 [M + H]+ 229.0859; found: 229.0855.
can be preparedRefinement
Crystal data, data collection and structure .
details are summarized in Table 1Structural data
CCDC reference: 1842060
https://doi.org/10.1107/S2414314618008520/bt4070sup1.cif
contains datablock I. DOI:Supporting information file. DOI: https://doi.org/10.1107/S2414314618008520/bt4070Isup2.cml
Data collection: CrysAlis PRO (Rigaku OD, 2015); cell
CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007; Palatinus & van der Lee, 2008; Palatinus et al., 2012); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).C14H12O3 | Dx = 1.503 Mg m−3 |
Mr = 228.24 | Melting point = 452–454 K |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.4539 (5) Å | Cell parameters from 3418 reflections |
b = 7.8553 (5) Å | θ = 2.3–30.9° |
c = 17.2286 (10) Å | µ = 0.11 mm−1 |
V = 1008.78 (11) Å3 | T = 150 K |
Z = 4 | Plate, colourless |
F(000) = 480 | 0.21 × 0.18 × 0.03 mm |
Rigaku Saturn724+ CCD diffractometer | 1769 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source | 1553 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.059 |
Detector resolution: 28.5714 pixels mm-1 | θmax = 25.0°, θmin = 2.4° |
ω scans | h = −8→6 |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | k = −9→9 |
Tmin = 0.874, Tmax = 1.000 | l = −20→20 |
5609 measured reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.042 | w = 1/[σ2(Fo2) + (0.0411P)2 + 0.1833P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.097 | (Δ/σ)max < 0.001 |
S = 1.07 | Δρmax = 0.27 e Å−3 |
1769 reflections | Δρmin = −0.25 e Å−3 |
154 parameters | Absolute structure: Flack x determined using 530 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
0 restraints | Absolute structure parameter: −0.4 (10) |
Primary atom site location: iterative |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
Refinement. All H atoms were placed in geometrically calculated positions and refined using a riding model with C–H distances of 1.00 Å for all H atoms bound to tertiary C(sp3) atoms and 0.99 Å for H atoms bound to secondary C(sp3) atoms. Isotropic displacement parameters for H atoms were calculated as Uiso(H) = 1.2Ueq(C). Due to the absence of anomalous scatterers, the absolute configuration could not be determined and was arbitrarily set. |
x | y | z | Uiso*/Ueq | ||
O1 | −0.4454 (3) | −0.5002 (3) | −0.44952 (13) | 0.0323 (6) | |
O2 | −0.7382 (3) | −0.2091 (3) | −0.31876 (12) | 0.0283 (6) | |
O3 | −0.7593 (4) | −0.5952 (3) | −0.57320 (12) | 0.0386 (7) | |
C1 | −0.7649 (5) | −0.7940 (4) | −0.25367 (17) | 0.0236 (7) | |
H1A | −0.678028 | −0.808534 | −0.210723 | 0.028* | |
H1B | −0.857452 | −0.884250 | −0.251388 | 0.028* | |
C2 | −0.8456 (4) | −0.6158 (4) | −0.25598 (17) | 0.0213 (7) | |
H2 | −0.917858 | −0.582697 | −0.209453 | 0.026* | |
C3 | −0.6831 (4) | −0.5005 (4) | −0.27393 (17) | 0.0212 (7) | |
H3 | −0.619466 | −0.458066 | −0.226618 | 0.025* | |
C4 | −0.5625 (4) | −0.6183 (4) | −0.32811 (17) | 0.0201 (7) | |
H4 | −0.438219 | −0.636161 | −0.307861 | 0.024* | |
C5 | −0.6744 (4) | −0.7835 (4) | −0.33247 (17) | 0.0213 (7) | |
H5 | −0.607082 | −0.887681 | −0.348789 | 0.026* | |
C6 | −0.8299 (4) | −0.7293 (4) | −0.38685 (18) | 0.0203 (7) | |
H6 | −0.891741 | −0.821255 | −0.416750 | 0.024* | |
C7 | −0.9485 (4) | −0.6135 (4) | −0.33487 (17) | 0.0189 (7) | |
H7 | −1.080298 | −0.637233 | −0.333650 | 0.023* | |
C8 | −0.8843 (4) | −0.4520 (4) | −0.38033 (17) | 0.0201 (7) | |
C9 | −0.7637 (4) | −0.5706 (4) | −0.43341 (17) | 0.0205 (7) | |
C10 | −0.5679 (4) | −0.5535 (4) | −0.41111 (17) | 0.0208 (7) | |
C11 | −0.7643 (4) | −0.3607 (4) | −0.32306 (17) | 0.0211 (7) | |
C12 | −1.0053 (4) | −0.3498 (4) | −0.43411 (18) | 0.0254 (8) | |
H12A | −0.956944 | −0.233685 | −0.441920 | 0.030* | |
H12B | −1.127812 | −0.340844 | −0.412290 | 0.030* | |
C13 | −1.0076 (5) | −0.4483 (5) | −0.51065 (19) | 0.0334 (9) | |
H13A | −1.109883 | −0.528665 | −0.511804 | 0.040* | |
H13B | −1.019144 | −0.368952 | −0.555029 | 0.040* | |
C14 | −0.8314 (4) | −0.5442 (4) | −0.51511 (18) | 0.0247 (7) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0259 (13) | 0.0392 (15) | 0.0317 (14) | −0.0016 (11) | 0.0053 (10) | 0.0096 (11) |
O2 | 0.0378 (13) | 0.0185 (12) | 0.0285 (12) | −0.0033 (11) | −0.0014 (11) | −0.0020 (10) |
O3 | 0.0414 (14) | 0.0544 (16) | 0.0201 (12) | 0.0079 (14) | 0.0019 (12) | −0.0031 (12) |
C1 | 0.0246 (17) | 0.0219 (16) | 0.0243 (17) | −0.0021 (15) | 0.0004 (14) | 0.0028 (14) |
C2 | 0.0229 (16) | 0.0238 (16) | 0.0173 (16) | 0.0012 (16) | 0.0031 (13) | −0.0018 (14) |
C3 | 0.0246 (16) | 0.0227 (17) | 0.0163 (15) | −0.0015 (15) | −0.0035 (13) | −0.0007 (14) |
C4 | 0.0158 (15) | 0.0242 (17) | 0.0202 (16) | 0.0019 (14) | −0.0023 (12) | 0.0021 (14) |
C5 | 0.0240 (16) | 0.0174 (15) | 0.0224 (18) | 0.0025 (15) | −0.0013 (14) | 0.0008 (13) |
C6 | 0.0219 (16) | 0.0191 (15) | 0.0198 (17) | −0.0015 (15) | −0.0026 (14) | −0.0009 (13) |
C7 | 0.0169 (15) | 0.0194 (16) | 0.0203 (16) | −0.0015 (13) | 0.0004 (13) | −0.0013 (13) |
C8 | 0.0195 (15) | 0.0219 (16) | 0.0188 (16) | −0.0019 (14) | −0.0027 (12) | 0.0002 (14) |
C9 | 0.0229 (15) | 0.0219 (16) | 0.0168 (14) | 0.0005 (14) | 0.0010 (14) | 0.0002 (13) |
C10 | 0.0199 (17) | 0.0176 (16) | 0.0249 (18) | 0.0019 (14) | 0.0042 (14) | 0.0004 (14) |
C11 | 0.0252 (16) | 0.0189 (17) | 0.0193 (15) | 0.0013 (15) | 0.0060 (14) | −0.0031 (13) |
C12 | 0.0265 (17) | 0.0277 (17) | 0.0219 (16) | 0.0061 (16) | −0.0012 (14) | 0.0011 (15) |
C13 | 0.034 (2) | 0.043 (2) | 0.0230 (19) | 0.0080 (18) | −0.0077 (15) | −0.0020 (17) |
C14 | 0.0284 (16) | 0.0279 (17) | 0.0177 (17) | −0.0014 (16) | −0.0006 (14) | 0.0009 (15) |
O1—C10 | 1.203 (4) | C5—C6 | 1.550 (4) |
O2—C11 | 1.209 (4) | C6—H6 | 1.0000 |
O3—C14 | 1.204 (4) | C6—C7 | 1.553 (4) |
C1—H1A | 0.9900 | C6—C9 | 1.562 (4) |
C1—H1B | 0.9900 | C7—H7 | 1.0000 |
C1—C2 | 1.524 (4) | C7—C8 | 1.566 (4) |
C1—C5 | 1.518 (4) | C8—C9 | 1.585 (4) |
C2—H2 | 1.0000 | C8—C11 | 1.513 (4) |
C2—C3 | 1.544 (4) | C8—C12 | 1.522 (4) |
C2—C7 | 1.561 (4) | C9—C10 | 1.516 (4) |
C3—H3 | 1.0000 | C9—C14 | 1.509 (4) |
C3—C4 | 1.592 (4) | C12—H12A | 0.9900 |
C3—C11 | 1.513 (4) | C12—H12B | 0.9900 |
C4—H4 | 1.0000 | C12—C13 | 1.529 (4) |
C4—C5 | 1.544 (4) | C13—H13A | 0.9900 |
C4—C10 | 1.518 (4) | C13—H13B | 0.9900 |
C5—H5 | 1.0000 | C13—C14 | 1.517 (5) |
H1A—C1—H1B | 110.1 | C6—C7—C2 | 102.4 (2) |
C2—C1—H1A | 112.6 | C6—C7—H7 | 117.5 |
C2—C1—H1B | 112.6 | C6—C7—C8 | 90.7 (2) |
C5—C1—H1A | 112.6 | C8—C7—H7 | 117.5 |
C5—C1—H1B | 112.6 | C7—C8—C9 | 89.2 (2) |
C5—C1—C2 | 95.9 (2) | C11—C8—C7 | 103.8 (2) |
C1—C2—H2 | 115.5 | C11—C8—C9 | 108.6 (2) |
C1—C2—C3 | 103.5 (2) | C11—C8—C12 | 119.9 (3) |
C1—C2—C7 | 103.2 (2) | C12—C8—C7 | 123.4 (3) |
C3—C2—H2 | 115.5 | C12—C8—C9 | 107.1 (2) |
C3—C2—C7 | 101.8 (2) | C6—C9—C8 | 89.7 (2) |
C7—C2—H2 | 115.5 | C10—C9—C6 | 104.1 (2) |
C2—C3—H3 | 113.8 | C10—C9—C8 | 110.4 (2) |
C2—C3—C4 | 102.6 (2) | C14—C9—C6 | 118.9 (3) |
C4—C3—H3 | 113.8 | C14—C9—C8 | 105.5 (2) |
C11—C3—C2 | 102.9 (2) | C14—C9—C10 | 123.1 (3) |
C11—C3—H3 | 113.8 | O1—C10—C4 | 128.0 (3) |
C11—C3—C4 | 108.6 (2) | O1—C10—C9 | 128.5 (3) |
C3—C4—H4 | 113.6 | C9—C10—C4 | 103.5 (2) |
C5—C4—C3 | 102.3 (2) | O2—C11—C3 | 128.0 (3) |
C5—C4—H4 | 113.6 | O2—C11—C8 | 127.0 (3) |
C10—C4—C3 | 110.0 (2) | C3—C11—C8 | 104.9 (2) |
C10—C4—H4 | 113.6 | C8—C12—H12A | 110.7 |
C10—C4—C5 | 102.8 (2) | C8—C12—H12B | 110.7 |
C1—C5—C4 | 104.0 (2) | C8—C12—C13 | 105.4 (3) |
C1—C5—H5 | 115.5 | H12A—C12—H12B | 108.8 |
C1—C5—C6 | 102.9 (2) | C13—C12—H12A | 110.7 |
C4—C5—H5 | 115.5 | C13—C12—H12B | 110.7 |
C4—C5—C6 | 101.7 (2) | C12—C13—H13A | 110.4 |
C6—C5—H5 | 115.5 | C12—C13—H13B | 110.4 |
C5—C6—H6 | 117.2 | H13A—C13—H13B | 108.6 |
C5—C6—C7 | 103.8 (2) | C14—C13—C12 | 106.6 (3) |
C5—C6—C9 | 107.1 (2) | C14—C13—H13A | 110.4 |
C7—C6—H6 | 117.2 | C14—C13—H13B | 110.4 |
C7—C6—C9 | 90.5 (2) | O3—C14—C9 | 125.5 (3) |
C9—C6—H6 | 117.2 | O3—C14—C13 | 126.4 (3) |
C2—C7—H7 | 117.5 | C9—C14—C13 | 108.1 (3) |
C2—C7—C8 | 107.2 (2) | ||
C1—C2—C3—C4 | 33.3 (3) | C7—C2—C3—C4 | −73.5 (2) |
C1—C2—C3—C11 | 146.1 (2) | C7—C2—C3—C11 | 39.3 (3) |
C1—C2—C7—C6 | −33.1 (3) | C7—C6—C9—C8 | 0.1 (2) |
C1—C2—C7—C8 | −127.7 (3) | C7—C6—C9—C10 | 111.1 (2) |
C1—C5—C6—C7 | 33.4 (3) | C7—C6—C9—C14 | −107.5 (3) |
C1—C5—C6—C9 | 128.3 (3) | C7—C8—C9—C6 | −0.1 (2) |
C2—C1—C5—C4 | 52.9 (3) | C7—C8—C9—C10 | −105.1 (3) |
C2—C1—C5—C6 | −52.8 (3) | C7—C8—C9—C14 | 119.8 (3) |
C2—C3—C4—C5 | −0.3 (3) | C7—C8—C11—O2 | −150.2 (3) |
C2—C3—C4—C10 | 108.4 (3) | C7—C8—C11—C3 | 30.7 (3) |
C2—C3—C11—O2 | 136.2 (3) | C7—C8—C12—C13 | −80.9 (4) |
C2—C3—C11—C8 | −44.7 (3) | C8—C9—C10—O1 | −116.4 (3) |
C2—C7—C8—C9 | 103.4 (2) | C8—C9—C10—C4 | 63.1 (3) |
C2—C7—C8—C11 | −5.6 (3) | C8—C9—C14—O3 | 169.8 (3) |
C2—C7—C8—C12 | −146.5 (3) | C8—C9—C14—C13 | −12.0 (3) |
C3—C2—C7—C6 | 74.0 (3) | C8—C12—C13—C14 | −27.4 (4) |
C3—C2—C7—C8 | −20.6 (3) | C9—C6—C7—C2 | −107.9 (2) |
C3—C4—C5—C1 | −33.0 (3) | C9—C6—C7—C8 | −0.1 (2) |
C3—C4—C5—C6 | 73.6 (3) | C9—C8—C11—O2 | 115.9 (4) |
C3—C4—C10—O1 | 117.1 (3) | C9—C8—C11—C3 | −63.2 (3) |
C3—C4—C10—C9 | −62.4 (3) | C9—C8—C12—C13 | 19.8 (3) |
C4—C3—C11—O2 | −115.5 (4) | C10—C4—C5—C1 | −147.2 (2) |
C4—C3—C11—C8 | 63.6 (3) | C10—C4—C5—C6 | −40.5 (3) |
C4—C5—C6—C7 | −74.1 (3) | C10—C9—C14—O3 | 42.0 (5) |
C4—C5—C6—C9 | 20.8 (3) | C10—C9—C14—C13 | −139.8 (3) |
C5—C1—C2—C3 | −52.9 (3) | C11—C3—C4—C5 | −108.8 (3) |
C5—C1—C2—C7 | 52.9 (3) | C11—C3—C4—C10 | −0.1 (3) |
C5—C4—C10—O1 | −134.5 (3) | C11—C8—C9—C6 | 104.2 (3) |
C5—C4—C10—C9 | 46.0 (3) | C11—C8—C9—C10 | −0.8 (3) |
C5—C6—C7—C2 | −0.1 (3) | C11—C8—C9—C14 | −135.9 (3) |
C5—C6—C7—C8 | 107.6 (2) | C11—C8—C12—C13 | 144.1 (3) |
C5—C6—C9—C8 | −104.5 (2) | C12—C8—C9—C6 | −125.0 (3) |
C5—C6—C9—C10 | 6.5 (3) | C12—C8—C9—C10 | 130.0 (3) |
C5—C6—C9—C14 | 147.9 (3) | C12—C8—C9—C14 | −5.0 (3) |
C6—C7—C8—C9 | 0.1 (2) | C12—C8—C11—O2 | −7.6 (5) |
C6—C7—C8—C11 | −108.9 (2) | C12—C8—C11—C3 | 173.3 (3) |
C6—C7—C8—C12 | 110.2 (3) | C12—C13—C14—O3 | −157.1 (3) |
C6—C9—C10—O1 | 148.6 (3) | C12—C13—C14—C9 | 24.8 (4) |
C6—C9—C10—C4 | −31.9 (3) | C14—C9—C10—O1 | 9.3 (5) |
C6—C9—C14—O3 | −91.8 (4) | C14—C9—C10—C4 | −171.3 (3) |
C6—C9—C14—C13 | 86.4 (3) |
Acknowledgements
We thank Mr Darshan Matre for his help in collecting the X-ray data.
Funding information
We thank the Defence Research and Development Organization (DRDO, No. ARDB/01/1041849/M/1), New Delhi for financial assistance. SK thanks the Department of Science and Technology (DST, No. SR/S2/JCB-33/2010) for the award of a J. C. Bose fellowship and Praj Industries for a Chair Professorship (Green Chemistry). SRC thanks the University Grants Commission (UGC), New Delhi for the award of a research fellowship and RG thanks Indian Institute of Technology (IIT) – Bombay, Mumbai for financial support as an Institute Research Associate (RA).
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