organic compounds
14-(4-Chlorophenyl)-14H-dibenzo[a,j]xanthene
aDepartment of Chemistry, Assam University, Silchar 788011, India, and bCentre for Soft Matter, Department of Chemistry, Assam University, Silchar 788011, India
*Correspondence e-mail: sudip.choudhury@aus.ac.in
In the title compound, C27H17ClO, the xanthene fused-ring system adopts a shallow butterfly conformation [dihedral angle between the two halves of the ring system = 22.9 (1)°. The dihedral angle between the central heteroyclic ring and the pendant chlorophenyl group is 87.60 (8)°. In the crystal, molecules are linked by weak C—H⋯π interactions.
Keywords: crystal structure; xanthene.
CCDC reference: 1887982
Structure description
The xanthene fused-ring building unit occurs in many natural et al., 1986; de la Fuente & Domínguez, 2007) and other biologically active compounds (Niu et al., 2012). In the arena of materials, dibenzo[a,j]xanthene derivatives have been reported to be promising hole-transporting materials for organic optoelectronic devices (Martins et al., 2017). Many reports on the synthesis of this class of compounds have been reported (Bartolomeu et al., 2014; Mirjalili et al., 2011). The present study of the title compound is a part of our work on the rapid synthesis of substituted dibenzo[a,j]xanthene derivatives as potential optical materials.
(BoenteFig. 1 shows the structure of the compound. The xanthene core has a shallow butterfly conformation with the angle between the planes of the naphthyl units (across the C6—O17 line) being 22.9 (1)°. The packing and the role of the different crystal symmetry operators in building it up are shown in Fig. 2a–c. The molecules are linked by weak C—H⋯π interaction and C—H⋯Cl hydrogen bonds (Table 1 and Fig. 2d).
Synthesis and crystallization
The title compound was synthesized by microwave irradiation of a mixture of 4-chlorobenzaldehyde (0.5 mmol) and 2-naphthol (1.0 mmol) in the presence of iodine (8 mol%) as cyclizing agent. After completion of the reaction, water and a few crystals of potassium iodide were added and the product was extracted with ethyl acetate. The crude product was purified by 1H NMR (CDCl3, 400 MHz) δH p.p.m.: 8.3 (d, J = 8.4 Hz, 2H, ArH), 7.83 (d,J = 8.0 Hz, 2H, ArH), 7.81 (t, J = 4.8 Hz, 2H, ArH), 7.80 (d, J = 8.8 Hz, 2H, ArH), 7.74 (m, 6H, ArH), 7.11 (d, J = 8.4 Hz, 2H, ArH), 6.458 (s,1H,CH). 13C NMR (CDCl3, 100 MHz) δ p.p.m.: 148.7, 143.4, 132.0, 131.2, 131.0, 129.4, 129.0, 128.9, 128.6, 126.9, 124.3, 122.4,118.0, 116.7, 37.3.
and was dissolved in ethyl acetate. The solution was kept undisturbed for few days in an NMR tube to obtain colourless needles of the title compound, yield 85%, m.p. 265°C;Refinement
Crystal data, data collection, and structure .
details are summarized in Table 2
|
Structural data
CCDC reference: 1887982
https://doi.org/10.1107/S2414314618018461/hb4276sup1.cif
contains datablocks global, New_Global_Publ_Block, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618018461/hb4276Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314618018461/hb4276Isup3.mol
Supporting information file. DOI: https://doi.org/10.1107/S2414314618018461/hb4276Isup4.cml
Data collection: APEX2 (Bruker, 2010); cell
SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: Superflip (Palatinus & Chapuis, 2007); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008), CAMERON (Watkin et al., 2003) and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).C27H17ClO | F(000) = 815.997 |
Mr = 392.88 | Dx = 1.354 Mg m−3 |
Orthorhombic, Pna21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2c -2n | Cell parameters from 9942 reflections |
a = 14.0201 (7) Å | θ = 2.8–24.1° |
b = 17.4488 (8) Å | µ = 0.21 mm−1 |
c = 7.8775 (3) Å | T = 296 K |
V = 1927.10 (15) Å3 | Needle, colourless |
Z = 4 | 0.40 × 0.21 × 0.10 mm |
BRUKER SMART APEXII diffractometer | 4052 reflections with I > 2.0σ(I) |
Graphite monochromator | Rint = 0.034 |
ω/2θ scans | θmax = 29.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Bruker, 2010) | h = −19→18 |
Tmin = 0.853, Tmax = 1 | k = −23→23 |
34384 measured reflections | l = −10→10 |
4980 independent reflections |
Refinement on F2 | H-atom parameters constrained |
Least-squares matrix: full | Method = Quasi-Unit weights W = 1.0 or 1./4Fsq |
R[F2 > 2σ(F2)] = 0.046 | (Δ/σ)max = 0.0002 |
wR(F2) = 0.053 | Δρmax = 0.42 e Å−3 |
S = 0.61 | Δρmin = −0.41 e Å−3 |
4970 reflections | Extinction correction: Larson (1970), Equation 22 |
264 parameters | Extinction coefficient: 140 (3) |
1 restraint | Absolute structure: Flack (1983), 2260 Friedel-pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.15 (5) |
Hydrogen site location: difference Fourier map |
Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems open-flow nitrogen cryostat (Cosier & Glazer, 1986) with a nominal stability of 0.1K. Cosier, J. & Glazer, A.M., 1986. J. Appl. Cryst. 105-107. |
Refinement. The H atoms attached to carbon atoms were located in difference maps and refined as riding atoms in their as-found relative locations. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.42137 (5) | 0.44109 (4) | −0.49033 (11) | 0.0905 | |
C2 | 0.35101 (15) | 0.45059 (11) | −0.3081 (3) | 0.0525 | |
C3 | 0.39356 (14) | 0.44159 (12) | −0.1537 (3) | 0.0574 | |
C4 | 0.33832 (12) | 0.44586 (10) | −0.0064 (3) | 0.0498 | |
C5 | 0.24104 (11) | 0.45958 (9) | −0.0168 (2) | 0.0386 | |
C6 | 0.17853 (13) | 0.46716 (10) | 0.1418 (2) | 0.0421 | |
C7 | 0.13553 (13) | 0.54701 (11) | 0.1471 (2) | 0.0450 | |
C8 | 0.19136 (16) | 0.61195 (11) | 0.1980 (3) | 0.0500 | |
C9 | 0.28621 (16) | 0.60620 (11) | 0.2561 (2) | 0.0560 | |
C10 | 0.3369 (2) | 0.66973 (14) | 0.3063 (3) | 0.0747 | |
C11 | 0.2959 (3) | 0.74292 (15) | 0.2984 (3) | 0.0821 | |
C12 | 0.2059 (3) | 0.75021 (14) | 0.2438 (3) | 0.0776 | |
C13 | 0.15026 (18) | 0.68635 (12) | 0.1914 (3) | 0.0626 | |
C14 | 0.0552 (2) | 0.69352 (14) | 0.1342 (3) | 0.0734 | |
C15 | 0.00195 (19) | 0.63196 (14) | 0.0875 (3) | 0.0676 | |
C16 | 0.04440 (15) | 0.55834 (13) | 0.0970 (2) | 0.0531 | |
O17 | −0.01588 (9) | 0.49912 (9) | 0.04831 (19) | 0.0608 | |
C18 | 0.01068 (14) | 0.42485 (12) | 0.0923 (2) | 0.0512 | |
C19 | 0.10051 (13) | 0.40635 (10) | 0.1441 (2) | 0.0415 | |
C20 | 0.11915 (14) | 0.32913 (10) | 0.1936 (2) | 0.0446 | |
C21 | 0.04471 (16) | 0.27372 (11) | 0.1814 (3) | 0.0533 | |
C22 | −0.04492 (17) | 0.29705 (15) | 0.1219 (3) | 0.0675 | |
C23 | −0.06320 (15) | 0.37023 (14) | 0.0807 (3) | 0.0640 | |
H231 | −0.1241 | 0.3856 | 0.0300 | 0.0765* | |
H221 | −0.0936 | 0.2577 | 0.0994 | 0.0807* | |
C24 | 0.0624 (2) | 0.19770 (13) | 0.2329 (3) | 0.0734 | |
C25 | 0.1482 (2) | 0.17598 (14) | 0.2956 (3) | 0.0773 | |
C26 | 0.22213 (19) | 0.22971 (12) | 0.3076 (3) | 0.0651 | |
C27 | 0.20808 (16) | 0.30473 (11) | 0.2575 (2) | 0.0520 | |
H271 | 0.2583 | 0.3393 | 0.2605 | 0.0622* | |
H261 | 0.2849 | 0.2188 | 0.3669 | 0.0779* | |
H251 | 0.1567 | 0.1211 | 0.3386 | 0.0907* | |
H241 | 0.0128 | 0.1608 | 0.2309 | 0.0876* | |
H151 | −0.0622 | 0.6373 | 0.0494 | 0.0807* | |
H141 | 0.0301 | 0.7435 | 0.1236 | 0.0901* | |
H121 | 0.1766 | 0.7974 | 0.2287 | 0.0959* | |
H111 | 0.3319 | 0.7883 | 0.3472 | 0.0967* | |
H101 | 0.4031 | 0.6629 | 0.3524 | 0.0904* | |
H91 | 0.3154 | 0.5576 | 0.2599 | 0.0665* | |
H61 | 0.2175 | 0.4624 | 0.2449 | 0.0468* | |
C28 | 0.20141 (14) | 0.46887 (11) | −0.1766 (2) | 0.0480 | |
C29 | 0.25589 (15) | 0.46442 (12) | −0.3222 (3) | 0.0562 | |
H291 | 0.2294 | 0.4713 | −0.4303 | 0.0667* | |
H281 | 0.1359 | 0.4806 | −0.1823 | 0.0578* | |
H41 | 0.3664 | 0.4380 | 0.0975 | 0.0603* | |
H31 | 0.4631 | 0.4339 | −0.1510 | 0.0692* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0832 (4) | 0.0975 (5) | 0.0909 (4) | 0.0033 (4) | 0.0486 (4) | 0.0036 (4) |
C2 | 0.0583 (14) | 0.0418 (11) | 0.0575 (12) | −0.0032 (10) | 0.0252 (11) | −0.0022 (11) |
C3 | 0.0360 (11) | 0.0498 (13) | 0.0865 (17) | −0.0012 (10) | 0.0105 (11) | −0.0150 (12) |
C4 | 0.0424 (11) | 0.0476 (11) | 0.0594 (12) | 0.0034 (9) | −0.0046 (10) | −0.0093 (11) |
C5 | 0.0357 (10) | 0.0311 (9) | 0.0491 (11) | 0.0013 (8) | −0.0018 (8) | −0.0044 (9) |
C6 | 0.0449 (11) | 0.0408 (10) | 0.0405 (11) | 0.0050 (9) | −0.0021 (8) | −0.0026 (9) |
C7 | 0.0536 (12) | 0.0419 (12) | 0.0394 (11) | 0.0128 (9) | 0.0049 (9) | −0.0008 (9) |
C8 | 0.0719 (14) | 0.0398 (11) | 0.0384 (10) | 0.0114 (11) | 0.0111 (10) | 0.0008 (9) |
C9 | 0.0712 (15) | 0.0424 (12) | 0.0545 (12) | 0.0005 (11) | 0.0016 (11) | −0.0066 (10) |
C10 | 0.095 (2) | 0.0604 (16) | 0.0690 (16) | −0.0117 (15) | −0.0041 (15) | −0.0122 (13) |
C11 | 0.123 (3) | 0.0550 (16) | 0.0678 (17) | −0.0101 (17) | 0.0063 (17) | −0.0167 (14) |
C12 | 0.128 (3) | 0.0348 (12) | 0.0703 (16) | 0.0099 (16) | 0.0237 (18) | −0.0007 (12) |
C13 | 0.0924 (19) | 0.0497 (13) | 0.0456 (12) | 0.0178 (13) | 0.0176 (13) | 0.0033 (11) |
C14 | 0.107 (2) | 0.0504 (14) | 0.0633 (16) | 0.0345 (15) | 0.0264 (15) | 0.0132 (12) |
C15 | 0.0720 (16) | 0.0778 (17) | 0.0530 (13) | 0.0381 (14) | 0.0086 (11) | 0.0146 (12) |
C16 | 0.0582 (13) | 0.0574 (13) | 0.0437 (11) | 0.0146 (12) | 0.0062 (9) | 0.0008 (11) |
O17 | 0.0489 (8) | 0.0754 (9) | 0.0579 (9) | 0.0158 (8) | −0.0042 (8) | 0.0039 (8) |
C18 | 0.0491 (12) | 0.0642 (15) | 0.0402 (11) | 0.0059 (11) | 0.0013 (9) | −0.0003 (10) |
C19 | 0.0414 (10) | 0.0498 (11) | 0.0333 (10) | 0.0023 (9) | 0.0024 (8) | −0.0004 (9) |
C20 | 0.0503 (12) | 0.0500 (11) | 0.0336 (10) | −0.0023 (10) | 0.0067 (9) | −0.0037 (9) |
C21 | 0.0579 (14) | 0.0571 (13) | 0.0449 (12) | −0.0095 (11) | 0.0116 (11) | −0.0032 (11) |
C22 | 0.0643 (16) | 0.0761 (17) | 0.0620 (16) | −0.0216 (14) | 0.0075 (12) | −0.0140 (13) |
C23 | 0.0445 (12) | 0.0964 (19) | 0.0510 (13) | −0.0026 (13) | −0.0015 (10) | −0.0089 (13) |
C24 | 0.090 (2) | 0.0611 (16) | 0.0694 (18) | −0.0232 (15) | 0.0155 (14) | −0.0003 (13) |
C25 | 0.115 (2) | 0.0465 (14) | 0.0704 (17) | −0.0047 (16) | 0.0155 (16) | 0.0081 (13) |
C26 | 0.0816 (18) | 0.0576 (15) | 0.0561 (14) | 0.0121 (13) | 0.0042 (13) | 0.0099 (12) |
C27 | 0.0613 (14) | 0.0463 (12) | 0.0484 (12) | 0.0019 (11) | 0.0060 (11) | 0.0026 (10) |
C28 | 0.0405 (10) | 0.0547 (12) | 0.0488 (11) | 0.0079 (10) | 0.0018 (10) | 0.0024 (10) |
C29 | 0.0563 (13) | 0.0629 (13) | 0.0494 (12) | 0.0067 (11) | 0.0070 (10) | 0.0038 (12) |
Cl1—C2 | 1.7496 (19) | C14—H141 | 0.944 |
C2—C3 | 1.364 (3) | C15—C16 | 1.418 (3) |
C2—C29 | 1.360 (3) | C15—H151 | 0.953 |
C3—C4 | 1.397 (3) | C16—O17 | 1.389 (2) |
C3—H31 | 0.985 | O17—C18 | 1.392 (2) |
C4—C5 | 1.387 (2) | C18—C19 | 1.363 (2) |
C4—H41 | 0.919 | C18—C23 | 1.411 (3) |
C5—C6 | 1.532 (2) | C19—C20 | 1.427 (2) |
C5—C28 | 1.386 (3) | C20—C21 | 1.426 (2) |
C6—C7 | 1.519 (3) | C20—C27 | 1.410 (3) |
C6—C19 | 1.524 (3) | C21—C22 | 1.402 (3) |
C6—H61 | 0.983 | C21—C24 | 1.409 (3) |
C7—C8 | 1.435 (3) | C22—C23 | 1.342 (3) |
C7—C16 | 1.352 (3) | C22—H221 | 0.985 |
C8—C9 | 1.410 (3) | C23—H231 | 0.981 |
C8—C13 | 1.421 (3) | C24—C25 | 1.355 (3) |
C9—C10 | 1.375 (3) | C24—H241 | 0.947 |
C9—H91 | 0.943 | C25—C26 | 1.401 (3) |
C10—C11 | 1.401 (3) | C25—H251 | 1.022 |
C10—H101 | 1.005 | C26—C27 | 1.381 (3) |
C11—C12 | 1.339 (4) | C26—H261 | 1.014 |
C11—H111 | 1.014 | C27—H271 | 0.928 |
C12—C13 | 1.422 (3) | C28—C29 | 1.380 (3) |
C12—H121 | 0.927 | C28—H281 | 0.942 |
C13—C14 | 1.412 (3) | C29—H291 | 0.937 |
C14—C15 | 1.359 (3) | ||
Cl1—C2—C3 | 118.32 (16) | C14—C15—H151 | 121.8 |
Cl1—C2—C29 | 120.18 (18) | C16—C15—H151 | 120.1 |
C3—C2—C29 | 121.47 (19) | C15—C16—C7 | 123.0 (2) |
C2—C3—C4 | 119.48 (18) | C15—C16—O17 | 113.84 (19) |
C2—C3—H31 | 117.9 | C7—C16—O17 | 123.15 (19) |
C4—C3—H31 | 122.6 | C16—O17—C18 | 117.46 (14) |
C3—C4—C5 | 120.4 (2) | O17—C18—C19 | 122.84 (18) |
C3—C4—H41 | 119.7 | O17—C18—C23 | 114.62 (18) |
C5—C4—H41 | 120.0 | C19—C18—C23 | 122.54 (19) |
C4—C5—C6 | 121.96 (18) | C6—C19—C18 | 119.65 (17) |
C4—C5—C28 | 117.91 (19) | C6—C19—C20 | 121.97 (16) |
C6—C5—C28 | 120.10 (15) | C18—C19—C20 | 118.35 (17) |
C5—C6—C7 | 109.18 (15) | C19—C20—C21 | 119.20 (17) |
C5—C6—C19 | 111.12 (14) | C19—C20—C27 | 122.99 (17) |
C7—C6—C19 | 110.71 (15) | C21—C20—C27 | 117.80 (17) |
C5—C6—H61 | 110.4 | C20—C21—C22 | 118.80 (19) |
C7—C6—H61 | 106.1 | C20—C21—C24 | 119.4 (2) |
C19—C6—H61 | 109.3 | C22—C21—C24 | 121.8 (2) |
C6—C7—C8 | 121.05 (16) | C21—C22—C23 | 121.9 (2) |
C6—C7—C16 | 120.09 (18) | C21—C22—H221 | 118.6 |
C8—C7—C16 | 118.81 (19) | C23—C22—H221 | 119.2 |
C7—C8—C9 | 123.31 (18) | C18—C23—C22 | 119.1 (2) |
C7—C8—C13 | 119.34 (19) | C18—C23—H231 | 118.8 |
C9—C8—C13 | 117.3 (2) | C22—C23—H231 | 121.7 |
C8—C9—C10 | 121.5 (2) | C21—C24—C25 | 121.6 (2) |
C8—C9—H91 | 119.0 | C21—C24—H241 | 120.4 |
C10—C9—H91 | 119.5 | C25—C24—H241 | 117.9 |
C9—C10—C11 | 120.7 (3) | C24—C25—C26 | 119.6 (2) |
C9—C10—H101 | 119.1 | C24—C25—H251 | 119.1 |
C11—C10—H101 | 120.1 | C26—C25—H251 | 121.2 |
C10—C11—C12 | 119.1 (3) | C25—C26—C27 | 120.6 (2) |
C10—C11—H111 | 119.4 | C25—C26—H261 | 123.2 |
C12—C11—H111 | 121.1 | C27—C26—H261 | 115.6 |
C11—C12—C13 | 122.4 (3) | C20—C27—C26 | 120.9 (2) |
C11—C12—H121 | 122.9 | C20—C27—H271 | 119.0 |
C13—C12—H121 | 114.5 | C26—C27—H271 | 120.0 |
C12—C13—C8 | 118.9 (2) | C5—C28—C29 | 121.77 (18) |
C12—C13—C14 | 122.8 (2) | C5—C28—H281 | 117.3 |
C8—C13—C14 | 118.4 (2) | C29—C28—H281 | 120.8 |
C13—C14—C15 | 122.3 (2) | C28—C29—C2 | 119.0 (2) |
C13—C14—H141 | 117.5 | C28—C29—H291 | 121.9 |
C15—C14—H141 | 120.1 | C2—C29—H291 | 119.0 |
C14—C15—C16 | 118.1 (2) |
Cg2 and Cg4 are the centroids of the C2–C5/C28/C29 and C8–C13 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H31···Cl1i | 0.98 | 3.00 | 3.547 (2) | 116 |
C12—H121···Cg2ii | 0.93 | 2.90 | 3.649 (3) | 138 |
C23—H231···Cg4iii | 0.98 | 3.00 | 3.740 (3) | 134 |
C25—H251···Cg2iv | 1.02 | 2.97 | 3.942 (3) | 160 |
Symmetry codes: (i) −x+1, −y+1, z+1/2; (ii) −x+1/2, y+1/2, z+1/2; (iii) −x, −y+1, z−1/2; (iv) −x+1/2, y−1/2, z+1/2. |
Acknowledgements
The authors thank the SAIF, Cochin University, for the NMR analysis and the SAIF, Gauhati University, for the single-crystal XRD facility.
Funding information
ARC thanks the University Grants Commission, India for a fellowship. Partial support from the NRB, India is acknowledged.
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