organic compounds
(E)-3-Thia-1,5(1,3)-dibenzenacycloundecaphan-8-ene-6,11-dione 3,3-dioxide
aDepartment of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai - 400076, India
*Correspondence e-mail: srk@chem.iitb.ac.in
The molecular structure of the title cyclophane, C20H18O4S, has two benzyl groups, a sulfone group, and two carbonyl groups adjacent to a double bond. The phenyl rings do not show intramolecular stacking.
Keywords: macrocycles; Grignard reaction; ring-closing metathesis; thiacyclophanes; crystal structure.
CCDC reference: 2040913
Structure description
Cyclophanes (Cram & Helgeson, 1966; Kotha et al., 2015) have become useful targets because of their unique structural features (Knobler et al., 1986). Their shapes are the main cause for their applications in supramolecular chemistry (Xu et al., 2008), material science (Yu et al., 2006) and medicinal chemistry (Lee et al., 2002). To this end, the synthesis of sulfur-containing cyclophanes (thiacyclophanes) has become of great interest for chemists (Nicolaou et al., 2010).
We have prepared novel thiacyclophanes using a simple strategy involving the Grignard reaction and ring-closing metathesis as key steps (Kotha et al., 2020). In this work, we present the single-crystal XRD study of the thiametacyclophane 1, which has two benzyl rings attached to an SO2 moiety and a bridge at the meta positions of the phenyl rings containing two carbonyl functions connected by a double bond (Fig. 1a). The angles between the S atom, the ansa-bridging methylene C atom and pivot atom of the phenyl ring i.e. S1—C1—C2 [114.1 (3)°] and S1—C20—C18 [114.8 (3)°] are slightly widened compared with an sp3-hybridized carbon atom. The structure has completely out-of-plane phenyl groups with no intramolecular interaction between them, as is evident from the top view of the compound (Mitchell & Lai, 1984) (Fig. 1b).
With respect to intermolecular interactions, no π–π stacking between adjacent phenyl rings is observed, as is evident from the packing diagram shown in Fig. 2. The phenyl rings do not share any overlap. Intermolecular hydrogen bonding is also absent.
Synthesis and crystallization
For the synthesis of the compound 1, we started with the preparation of the dialdehyde 2 (Kotha et al., 2020). Later on, a Grignard reaction with 2 gave 3, which on further oxidation provided the sulfone 4. In an oven-dried, two-neck round-bottom flask, compound 4 (1eq., 50 mg) was dissolved in dry dichloromethane (20 ml). 1 Drop (0.1 eq.) of Ti(OiPr)4 was added under an inert atmosphere and the reaction mixture was degassed by nitrogen gas. After degasification, Grubbs' second generation catalyst (5–10 mmol-%) was added, and the reaction mixture was refluxed. After completion of the reaction (TLC monitoring), the crude product was then subjected to oxidation by using pyridinium chlorochromate (2.5 eq.) at room temperature. After completion of the reaction (TLC monitoring), the product was concentrated and purified by silica gel using petroleum ether and ethyl acetate as the to afford the desired compound 1 (Fig. 3). The single crystals were obtained by recrystallization in ethyl acetate and petroleum ether (1:2).
Yield 27 mg, 58%, m.p. 186–188°C, appearance: colourless solid, Rf = 0.5 (50% EtOAc–petroleum ether), 1H NMR 400 MHz, CDCl3) δ 8.04 (d, J = 8.0 Hz, 2H), 7.91 (d, J = 8.0 Hz, 2H), 7.56–7.51 (m, 4H), 5.83 (t, J = 3.2 Hz, 2H), 4.08 (s, 4H), 3.59 (m, 4H) p.p.m., 13C NMR (100 MHz, CDCl3) δ 197.1, 136.9, 135.4, 131.2, 130.1, 129.4, 128.7, 127.8, 57.1, 43.7 p.p.m., HRMS (ESI) m/z calculated C20H18O4SK[M + K]+ 393.0557, found 393.0551.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 1Structural data
CCDC reference: 2040913
https://doi.org/10.1107/S2414314620014649/bt4102sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620014649/bt4102Isup2.hkl
Data collection: CrysAlis PRO (Rigaku, 2018); cell
CrysAlis PRO (Rigaku, 2018); data reduction: CrysAlis PRO (Rigaku, 2018); program(s) used to solve structure: ShelXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).C20H18O4S | F(000) = 744 |
Mr = 354.40 | Dx = 1.403 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 8.4257 (11) Å | Cell parameters from 1833 reflections |
b = 9.0522 (9) Å | θ = 2.4–26.4° |
c = 22.237 (2) Å | µ = 0.22 mm−1 |
β = 98.303 (12)° | T = 150 K |
V = 1678.3 (3) Å3 | Block, colourless |
Z = 4 | 0.14 × 0.09 × 0.03 mm |
Rigaku Saturn724+ diffractometer | 2942 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source | 1671 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.083 |
Detector resolution: 28.5714 pixels mm-1 | θmax = 25.0°, θmin = 2.4° |
ω scans | h = −9→10 |
Absorption correction: multi-scan (CrysAlisPro; Rigaku, 2018) | k = −7→10 |
Tmin = 0.921, Tmax = 1.000 | l = −18→26 |
6670 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.069 | H-atom parameters constrained |
wR(F2) = 0.165 | w = 1/[σ2(Fo2) + (0.0393P)2 + 0.7221P] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max < 0.001 |
2942 reflections | Δρmax = 0.42 e Å−3 |
226 parameters | Δρmin = −0.42 e Å−3 |
0 restraints |
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. H atoms were refined using a riding model with U(H)=1.2UeqC and with Caromatic—H = 0.95?Å or Cmethylene—H = 0.99?Å. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.78574 (15) | 0.72123 (11) | 0.70216 (5) | 0.0316 (4) | |
O2 | 0.7211 (4) | 0.8626 (3) | 0.68124 (14) | 0.0421 (9) | |
O1 | 0.8964 (4) | 0.7170 (3) | 0.75787 (13) | 0.0392 (9) | |
O3 | 0.1830 (4) | 0.3005 (3) | 0.50373 (14) | 0.0475 (10) | |
O4 | 1.0566 (4) | −0.0096 (3) | 0.62633 (17) | 0.0515 (10) | |
C6 | 1.0134 (5) | 0.2434 (4) | 0.64281 (18) | 0.0267 (10) | |
C14 | 0.3355 (6) | 0.4516 (4) | 0.57729 (19) | 0.0305 (11) | |
C1 | 0.8785 (5) | 0.6454 (4) | 0.64184 (18) | 0.0267 (11) | |
H1A | 0.7948 | 0.6265 | 0.6067 | 0.032* | |
H1B | 0.9536 | 0.7194 | 0.6291 | 0.032* | |
C8 | 0.9719 (6) | 0.0980 (4) | 0.6111 (2) | 0.0325 (11) | |
C7 | 0.9243 (5) | 0.3719 (4) | 0.62869 (18) | 0.0249 (10) | |
H7 | 0.8320 | 0.3692 | 0.5986 | 0.030* | |
C15 | 0.2412 (5) | 0.5744 (5) | 0.5605 (2) | 0.0323 (11) | |
H15 | 0.1555 | 0.5682 | 0.5278 | 0.039* | |
C2 | 0.9693 (5) | 0.5035 (4) | 0.65816 (18) | 0.0250 (10) | |
C19 | 0.4621 (5) | 0.4625 (4) | 0.62534 (18) | 0.0267 (10) | |
H19 | 0.5263 | 0.3782 | 0.6372 | 0.032* | |
C4 | 1.1943 (5) | 0.3788 (5) | 0.7164 (2) | 0.0347 (12) | |
H4 | 1.2863 | 0.3821 | 0.7466 | 0.042* | |
C13 | 0.2932 (6) | 0.3062 (5) | 0.5460 (2) | 0.0352 (12) | |
C3 | 1.1054 (5) | 0.5051 (5) | 0.7015 (2) | 0.0315 (11) | |
H3 | 1.1382 | 0.5952 | 0.7215 | 0.038* | |
C9 | 0.8348 (5) | 0.0863 (5) | 0.5607 (2) | 0.0357 (12) | |
H9A | 0.8362 | −0.0127 | 0.5419 | 0.043* | |
H9B | 0.8486 | 0.1605 | 0.5291 | 0.043* | |
C11 | 0.5455 (5) | 0.1580 (4) | 0.5472 (2) | 0.0329 (11) | |
H11 | 0.5545 | 0.1882 | 0.5069 | 0.040* | |
C5 | 1.1485 (5) | 0.2470 (4) | 0.68701 (18) | 0.0302 (11) | |
H5 | 1.2091 | 0.1596 | 0.6970 | 0.036* | |
C17 | 0.3971 (6) | 0.7161 (4) | 0.63881 (19) | 0.0319 (11) | |
H17 | 0.4166 | 0.8070 | 0.6600 | 0.038* | |
C16 | 0.2725 (5) | 0.7065 (5) | 0.59171 (19) | 0.0337 (12) | |
H16 | 0.2076 | 0.7906 | 0.5804 | 0.040* | |
C12 | 0.3844 (6) | 0.1679 (4) | 0.5677 (2) | 0.0349 (12) | |
H12A | 0.3985 | 0.1652 | 0.6127 | 0.042* | |
H12B | 0.3200 | 0.0805 | 0.5525 | 0.042* | |
C18 | 0.4949 (5) | 0.5959 (4) | 0.65603 (19) | 0.0271 (10) | |
C10 | 0.6757 (6) | 0.1099 (4) | 0.5816 (2) | 0.0339 (12) | |
H10 | 0.6680 | 0.0885 | 0.6229 | 0.041* | |
C20 | 0.6247 (5) | 0.6022 (4) | 0.71042 (19) | 0.0293 (11) | |
H20A | 0.6675 | 0.5013 | 0.7188 | 0.035* | |
H20B | 0.5760 | 0.6343 | 0.7462 | 0.035* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0419 (8) | 0.0204 (6) | 0.0310 (6) | −0.0001 (5) | 0.0005 (6) | −0.0055 (5) |
O2 | 0.054 (2) | 0.0163 (14) | 0.053 (2) | 0.0032 (15) | −0.0005 (18) | −0.0051 (14) |
O1 | 0.045 (2) | 0.0354 (17) | 0.0338 (18) | 0.0011 (15) | −0.0077 (16) | −0.0115 (14) |
O3 | 0.046 (2) | 0.053 (2) | 0.038 (2) | 0.0074 (17) | −0.0131 (18) | −0.0068 (16) |
O4 | 0.038 (2) | 0.0275 (17) | 0.085 (3) | 0.0069 (16) | −0.002 (2) | −0.0016 (17) |
C6 | 0.030 (3) | 0.026 (2) | 0.025 (2) | 0.000 (2) | 0.006 (2) | 0.0027 (18) |
C14 | 0.033 (3) | 0.030 (2) | 0.028 (3) | 0.002 (2) | 0.003 (2) | 0.0018 (19) |
C1 | 0.037 (3) | 0.019 (2) | 0.023 (2) | −0.003 (2) | 0.002 (2) | −0.0017 (18) |
C8 | 0.037 (3) | 0.026 (2) | 0.035 (3) | −0.001 (2) | 0.008 (2) | −0.003 (2) |
C7 | 0.024 (3) | 0.027 (2) | 0.023 (2) | 0.001 (2) | 0.000 (2) | 0.0004 (18) |
C15 | 0.030 (3) | 0.041 (3) | 0.027 (3) | 0.007 (2) | 0.005 (2) | 0.009 (2) |
C2 | 0.032 (3) | 0.023 (2) | 0.021 (2) | −0.003 (2) | 0.005 (2) | 0.0038 (18) |
C19 | 0.027 (3) | 0.024 (2) | 0.030 (2) | 0.007 (2) | 0.009 (2) | 0.0038 (18) |
C4 | 0.026 (3) | 0.046 (3) | 0.030 (3) | −0.005 (2) | −0.001 (2) | −0.001 (2) |
C13 | 0.036 (3) | 0.044 (3) | 0.026 (2) | 0.006 (2) | 0.003 (2) | −0.001 (2) |
C3 | 0.032 (3) | 0.028 (2) | 0.034 (3) | 0.000 (2) | 0.004 (2) | −0.0016 (19) |
C9 | 0.037 (3) | 0.029 (2) | 0.040 (3) | 0.006 (2) | 0.001 (2) | −0.007 (2) |
C11 | 0.037 (3) | 0.025 (2) | 0.036 (3) | 0.000 (2) | 0.001 (2) | −0.008 (2) |
C5 | 0.030 (3) | 0.031 (2) | 0.030 (2) | −0.002 (2) | 0.004 (2) | 0.005 (2) |
C17 | 0.038 (3) | 0.027 (2) | 0.032 (3) | 0.009 (2) | 0.010 (2) | 0.003 (2) |
C16 | 0.036 (3) | 0.031 (2) | 0.034 (3) | 0.012 (2) | 0.004 (2) | 0.014 (2) |
C12 | 0.043 (3) | 0.029 (2) | 0.032 (3) | −0.005 (2) | 0.001 (2) | −0.003 (2) |
C18 | 0.028 (3) | 0.027 (2) | 0.028 (2) | −0.001 (2) | 0.009 (2) | 0.0023 (19) |
C10 | 0.039 (3) | 0.027 (2) | 0.031 (3) | 0.002 (2) | −0.006 (2) | −0.0037 (19) |
C20 | 0.038 (3) | 0.025 (2) | 0.026 (2) | 0.001 (2) | 0.007 (2) | 0.0033 (18) |
S1—O2 | 1.441 (3) | C4—H4 | 0.9500 |
S1—O1 | 1.439 (3) | C4—C3 | 1.380 (6) |
S1—C1 | 1.785 (4) | C4—C5 | 1.388 (5) |
S1—C20 | 1.763 (4) | C13—C12 | 1.511 (6) |
O3—C13 | 1.223 (5) | C3—H3 | 0.9500 |
O4—C8 | 1.226 (5) | C9—H9A | 0.9900 |
C6—C8 | 1.510 (5) | C9—H9B | 0.9900 |
C6—C7 | 1.395 (5) | C9—C10 | 1.497 (6) |
C6—C5 | 1.393 (5) | C11—H11 | 0.9500 |
C14—C15 | 1.386 (6) | C11—C12 | 1.496 (6) |
C14—C19 | 1.400 (5) | C11—C10 | 1.318 (5) |
C14—C13 | 1.507 (6) | C5—H5 | 0.9500 |
C1—H1A | 0.9900 | C17—H17 | 0.9500 |
C1—H1B | 0.9900 | C17—C16 | 1.375 (6) |
C1—C2 | 1.512 (5) | C17—C18 | 1.385 (5) |
C8—C9 | 1.492 (6) | C16—H16 | 0.9500 |
C7—H7 | 0.9500 | C12—H12A | 0.9900 |
C7—C2 | 1.385 (5) | C12—H12B | 0.9900 |
C15—H15 | 0.9500 | C18—C20 | 1.510 (6) |
C15—C16 | 1.389 (6) | C10—H10 | 0.9500 |
C2—C3 | 1.388 (6) | C20—H20A | 0.9900 |
C19—H19 | 0.9500 | C20—H20B | 0.9900 |
C19—C18 | 1.395 (5) | ||
O2—S1—C1 | 106.56 (19) | C2—C3—H3 | 119.2 |
O2—S1—C20 | 108.4 (2) | C4—C3—C2 | 121.5 (4) |
O1—S1—O2 | 117.98 (18) | C4—C3—H3 | 119.2 |
O1—S1—C1 | 109.7 (2) | C8—C9—H9A | 109.0 |
O1—S1—C20 | 107.84 (19) | C8—C9—H9B | 109.0 |
C20—S1—C1 | 105.7 (2) | C8—C9—C10 | 112.8 (4) |
C7—C6—C8 | 122.7 (4) | H9A—C9—H9B | 107.8 |
C5—C6—C8 | 117.4 (4) | C10—C9—H9A | 109.0 |
C5—C6—C7 | 119.8 (4) | C10—C9—H9B | 109.0 |
C15—C14—C19 | 119.5 (4) | C12—C11—H11 | 118.0 |
C15—C14—C13 | 119.2 (4) | C10—C11—H11 | 118.0 |
C19—C14—C13 | 121.2 (4) | C10—C11—C12 | 123.9 (4) |
S1—C1—H1A | 108.7 | C6—C5—H5 | 120.2 |
S1—C1—H1B | 108.7 | C4—C5—C6 | 119.7 (4) |
H1A—C1—H1B | 107.6 | C4—C5—H5 | 120.2 |
C2—C1—S1 | 114.1 (3) | C16—C17—H17 | 119.4 |
C2—C1—H1A | 108.7 | C16—C17—C18 | 121.3 (4) |
C2—C1—H1B | 108.7 | C18—C17—H17 | 119.4 |
O4—C8—C6 | 118.5 (4) | C15—C16—H16 | 119.9 |
O4—C8—C9 | 120.5 (4) | C17—C16—C15 | 120.3 (4) |
C9—C8—C6 | 121.0 (4) | C17—C16—H16 | 119.9 |
C6—C7—H7 | 119.7 | C13—C12—H12A | 108.9 |
C2—C7—C6 | 120.6 (4) | C13—C12—H12B | 108.9 |
C2—C7—H7 | 119.7 | C11—C12—C13 | 113.2 (4) |
C14—C15—H15 | 120.1 | C11—C12—H12A | 108.9 |
C14—C15—C16 | 119.8 (4) | C11—C12—H12B | 108.9 |
C16—C15—H15 | 120.1 | H12A—C12—H12B | 107.8 |
C7—C2—C1 | 121.5 (4) | C19—C18—C20 | 119.6 (4) |
C7—C2—C3 | 118.7 (4) | C17—C18—C19 | 118.5 (4) |
C3—C2—C1 | 119.8 (3) | C17—C18—C20 | 121.7 (4) |
C14—C19—H19 | 119.7 | C9—C10—H10 | 117.5 |
C18—C19—C14 | 120.6 (4) | C11—C10—C9 | 125.0 (4) |
C18—C19—H19 | 119.7 | C11—C10—H10 | 117.5 |
C3—C4—H4 | 120.2 | S1—C20—H20A | 108.6 |
C3—C4—C5 | 119.7 (4) | S1—C20—H20B | 108.6 |
C5—C4—H4 | 120.2 | C18—C20—S1 | 114.8 (3) |
O3—C13—C14 | 119.6 (4) | C18—C20—H20A | 108.6 |
O3—C13—C12 | 120.3 (4) | C18—C20—H20B | 108.6 |
C14—C13—C12 | 120.0 (4) | H20A—C20—H20B | 107.6 |
S1—C1—C2—C7 | 117.0 (4) | C7—C2—C3—C4 | −1.1 (7) |
S1—C1—C2—C3 | −66.1 (5) | C15—C14—C19—C18 | −0.6 (7) |
O2—S1—C1—C2 | 173.6 (3) | C15—C14—C13—O3 | 4.7 (7) |
O2—S1—C20—C18 | 50.0 (3) | C15—C14—C13—C12 | −174.0 (4) |
O1—S1—C1—C2 | 44.9 (4) | C19—C14—C15—C16 | −0.4 (7) |
O1—S1—C20—C18 | 178.8 (3) | C19—C14—C13—O3 | −179.2 (4) |
O3—C13—C12—C11 | 103.5 (5) | C19—C14—C13—C12 | 2.1 (7) |
O4—C8—C9—C10 | 115.5 (5) | C19—C18—C20—S1 | 118.1 (4) |
C6—C8—C9—C10 | −66.8 (5) | C13—C14—C15—C16 | 175.8 (4) |
C6—C7—C2—C1 | 177.5 (4) | C13—C14—C19—C18 | −176.7 (4) |
C6—C7—C2—C3 | 0.6 (6) | C3—C4—C5—C6 | 0.0 (7) |
C14—C15—C16—C17 | 0.4 (7) | C5—C6—C8—O4 | 1.3 (6) |
C14—C19—C18—C17 | 1.5 (6) | C5—C6—C8—C9 | −176.4 (4) |
C14—C19—C18—C20 | 175.8 (4) | C5—C6—C7—C2 | 0.2 (6) |
C14—C13—C12—C11 | −77.8 (5) | C5—C4—C3—C2 | 0.8 (7) |
C1—S1—C20—C18 | −63.9 (3) | C17—C18—C20—S1 | −67.7 (5) |
C1—C2—C3—C4 | −178.1 (4) | C16—C17—C18—C19 | −1.5 (7) |
C8—C6—C7—C2 | −178.5 (4) | C16—C17—C18—C20 | −175.7 (4) |
C8—C6—C5—C4 | 178.3 (4) | C12—C11—C10—C9 | 174.3 (4) |
C8—C9—C10—C11 | 154.2 (4) | C18—C17—C16—C15 | 0.5 (7) |
C7—C6—C8—O4 | −180.0 (4) | C10—C11—C12—C13 | 139.7 (4) |
C7—C6—C8—C9 | 2.3 (7) | C20—S1—C1—C2 | −71.2 (3) |
C7—C6—C5—C4 | −0.5 (6) |
Footnotes
‡NKG and SA contributed equally.
Acknowledgements
We thank Mr Darshan S Mhatre for his help in collecting the X-ray data and with the structure refinement.
Funding information
Funding for this research was provided by: Department of Science and Technology, Ministry of Science and Technology, India (award No. SR/S2/JCB-33/2010 to Sambasivarao Kotha); Council of Scientific and Industrial Research, India (scholarship to Naveen Kumar Gupta); University Grants Commission (scholarship to Saima Ansari).
References
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