organic compounds
Ethyl 6-(4-chlorophenyl)-2,2-dimethyl-4-oxo-3,4-dihydro-2H-pyran-5-carboxylate
aPostgraduate and Research Department of Physics, National College (Autonomous), Tiruchirappalli 620 001, Tamilnadu, India, bSchool of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamilnadu, India, and cLaboratorio de Políimeros, Centro de Química Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla (BUAP), Complejo de Ciencias, ICUAP, Edif. 103H, 22 Sur y San Claudio, CP 72570 Puebla, Puebla, Mexico
*Correspondence e-mail: sunvag@gmail.com
The title compound, C16H17ClO4, is a derivative of 3,4-dihydro-2H-pyran-4-one in which the root moiety forms a dihedral angle of 49.36 (5)° with the pendent chlorobenzene ring. The features weak methyl-C—H⋯O(ring carbonyl) contacts, leading to an R22(12) ring motif, and benzene-C—H⋯O(ester) interactions, leading to a supramolecular chain along the b axis, to form a three-dimensional network.
Keywords: crystal structure; pyran-4-one; C—H⋯O interactions.
CCDC reference: 1526174
Structure description
4H-Pyran-4-ones and their various derivatives are known for their significant biological and pharmacological activities, and are structurally similar to biologically active 1,4-dihydropyridines (1,4-DHPs) (Zonouz et al., 2014). They act as calcium antagonists (Súarez et al., 2002) and serve as potent apoptosis inducers (Zhang et al., 2005). As a continuation of structural investigations of a series of 4H-pyran-4-one derivatives, we report herein on the determination and the geometry optimization of the title compound, (I).
A perspective view of (I) with the atomic numbering scheme is illustrated in Fig. 1. The 3,4-dihydro-2H-pyran-4-one moiety (C7–C11/O1/O2) forms a dihedral angle of 49.36 (5)° with the benzene ring. The bond distances and angles are essentially equivalent compared to those in the previously reported structure ethyl 2,2-dimethyl-4-oxo-6-phenyl-3,4-dihydro-2H-pyran-5-carboxylate (II) (Sharmila et al., 2016). However, the benzene group has rotated about the C6—C7 bond as evident from the change in torsion angles namely, C1—C6—C7—C11 and C5—C6—C7—C11 of −133.37 (15) and 50.56 (19)°, respectively, cf. 138.6 (2) and −43.3 (3)° in (II). Also, a fragment overlay (Gans & Shalloway, 2001) analysis of (I) with (II) gives an r.m.s. deviation of 2.91 Å (Fig. 2). These observations indicate that the structural changes could be attributed to the substitution of the heavier Cl atom at C3 and the involvement of C2 in making a hydrogen bond with O4 via H2 (Table 1). Another superposition analysis of (I) but, with 4-(4-fluorophenyl)-6-methylamino-5-nitro-2-phenyl-4H-pyran-3- carbonitrile (III) (Vishnupriya et al., 2013) gives an r.m.s. deviation of 1.57 Å, which confirms the effect of relatively heavier Cl substitution at C3 resulting in the small conformational changes in the molecule.
The pyran ring of (I) is puckered (puckering parameters: Q = 0.4539 (16) Å, q2 = 0.378 (15) Å, q3 = −0.2512 (15) Å, θ = 123.61 (19)° and φ = 91.6 (2)°, with atom C8 showing the maximum deviation of 0.2946 (16) Å from the plane defined by O1/C7/C11–C8.
Theoretical calculations of the molecular structure were performed using MOPAC2016′s PM7 geometry optimization algorithm (Stewart, 2016). This shows satisfactory agreement with the results of the X-ray analysis. The HOMO and LUMO energy levels were found to be −9.829 and −1.127 eV, respectively. The total energy and values of (I) are −3643.34886 eV and 5.235 Debye, respectively. In the geometry optimized structure of (I), a decrease in bond distances seems to be observed for the bonds O1—C8 (1.46 Å) and C6—C7 (1.47 Å) when compared to those in the crystal, i.e. 1.4732 (16) and 1.4832 (16) Å. The O1—C7—C6 bond angle decreased from 110.78 (11) to 110.2°, and the O1—C8—C9 bond angle increased from 108.65 (11) to 110.5°. The relative conformation about the bond joining the 3,4-dihydro-2H-pyran-4-one moiety with the chlorobenzene group of (I) is defined by the torsion angles C1—C6—C7—O1 and C5—C6—C7—O1 of 47.68 (17) and −128.38 (13)° in the crystal, i.e. show (+) syn-clinal and (−) anti-clinal conformations, respectively, and compare with 49.9 and −130.8° in the optimized structure. A superimposed fit of (I) with its energy-minimized molecule gives an r.m.s. deviation of 0.152 Å (Fig. 3).
One of the methyl carbons, C15, is involved in hydrogen bond with O2 of a symmetry-related molecule via H15B to form a R22(12) ring motif. The phenyl carbon C2 is involved in an interaction with O4 of a symmetry-related molecule via H2 to form a chain along the b axis (Table 1 and Fig. 4). These combine to give a three-dimensional architecture. Further, a weak C—H⋯π interaction between C13 and the centroid (Cg) of the C1–C6 ring via H13B, provides additional stabilization to the crystal (Table 1).
Synthesis and crystallization
To a solution of ethyl 3-(4-chlorophenyl)-3-oxopropanoate (226 mg, 1.0 mmol), CaCl2 (11 mg, 0.1 mmol), triethylamine (278 µL, 2.0 mmol) and 3-methylbut-2-enoyl chloride (112 µL, 1.0 mmol), dichloromethane (4 ml) was added at ambient temperature. After completion of the addition, the reaction mixture was subjected to stirring at room temperature for 3 h. The progress of the reaction was monitored by The organic layer was separated, filtered and concentrated. The crude product was purified by silica gel (EtOAc/hexane = 2:8 v/v as eluent). The product was a colourless solid (yield 90%, 277 mg) and was crystallized in hexane/EtOAc (6:4 v/v (m.p. 354–356 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2
|
Structural data
CCDC reference: 1526174
https://doi.org/10.1107/S2414314617000347/tk4027sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314617000347/tk4027Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314617000347/tk4027Isup3.cml
Data collection: SMART (Bruker, 2008); cell
SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: QMOL (Gans & Shalloway, 2001), Mercury (Macrae et al., 2008) and ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: WinGX publication routines (Farrugia, 2012) and PLATON (Spek, 2009).C16H17ClO4 | Dx = 1.289 Mg m−3 |
Mr = 308.74 | Melting point: 356 K |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 10.4412 (3) Å | Cell parameters from 3995 reflections |
b = 7.6959 (2) Å | θ = 2.0–28.4° |
c = 20.2651 (5) Å | µ = 0.25 mm−1 |
β = 102.311 (2)° | T = 296 K |
V = 1590.94 (7) Å3 | Block, colourless |
Z = 4 | 0.25 × 0.17 × 0.12 mm |
F(000) = 648 |
Bruker Smart CCD Area-detector diffractometer | 3995 independent reflections |
Radiation source: fine-focus sealed tube | 2978 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.018 |
phi and ω scans | θmax = 28.4°, θmin = 2.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | h = −13→13 |
Tmin = 0.746, Tmax = 0.845 | k = −10→10 |
15125 measured reflections | l = −24→27 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.108 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0484P)2 + 0.3683P] where P = (Fo2 + 2Fc2)/3 |
3995 reflections | (Δ/σ)max < 0.001 |
193 parameters | Δρmax = 0.28 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
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. |
x | y | z | Uiso*/Ueq | ||
Cl1 | 0.43713 (4) | 0.28175 (7) | 0.02231 (2) | 0.06956 (16) | |
O1 | 0.76719 (10) | 0.25784 (13) | 0.33513 (5) | 0.0475 (2) | |
O2 | 1.03226 (13) | 0.63993 (19) | 0.40015 (6) | 0.0736 (4) | |
O3 | 0.96413 (11) | 0.71077 (17) | 0.24439 (7) | 0.0670 (3) | |
O4 | 0.76146 (10) | 0.76716 (13) | 0.25811 (5) | 0.0494 (3) | |
C1 | 0.56401 (14) | 0.3304 (2) | 0.22085 (7) | 0.0476 (3) | |
H1 | 0.5298 | 0.3190 | 0.2594 | 0.057* | |
C2 | 0.48338 (14) | 0.3058 (2) | 0.15815 (7) | 0.0515 (4) | |
H2 | 0.3950 | 0.2802 | 0.1541 | 0.062* | |
C3 | 0.53638 (14) | 0.3198 (2) | 0.10154 (7) | 0.0451 (3) | |
C4 | 0.66627 (14) | 0.3583 (2) | 0.10654 (7) | 0.0464 (3) | |
H4 | 0.7003 | 0.3669 | 0.0678 | 0.056* | |
C5 | 0.74647 (13) | 0.38433 (18) | 0.16963 (7) | 0.0420 (3) | |
H5 | 0.8347 | 0.4102 | 0.1733 | 0.050* | |
C6 | 0.69542 (12) | 0.37183 (17) | 0.22726 (6) | 0.0368 (3) | |
C7 | 0.78238 (12) | 0.39149 (17) | 0.29499 (6) | 0.0374 (3) | |
C8 | 0.83024 (15) | 0.2695 (2) | 0.40731 (7) | 0.0498 (4) | |
C9 | 0.96580 (15) | 0.3470 (2) | 0.41366 (7) | 0.0524 (4) | |
H9A | 1.0057 | 0.3629 | 0.4611 | 0.063* | |
H9B | 1.0200 | 0.2667 | 0.3948 | 0.063* | |
C10 | 0.96159 (14) | 0.5182 (2) | 0.37801 (7) | 0.0486 (3) | |
C11 | 0.86698 (12) | 0.52417 (18) | 0.31346 (6) | 0.0391 (3) | |
C12 | 0.87223 (13) | 0.67511 (18) | 0.26829 (7) | 0.0415 (3) | |
C13 | 0.75166 (17) | 0.9164 (2) | 0.21306 (9) | 0.0601 (4) | |
H13A | 0.8384 | 0.9637 | 0.2147 | 0.072* | |
H13B | 0.6989 | 1.0060 | 0.2279 | 0.072* | |
C14 | 0.6913 (2) | 0.8648 (3) | 0.14272 (10) | 0.0745 (5) | |
H14A | 0.7470 | 0.7826 | 0.1269 | 0.112* | |
H14B | 0.6805 | 0.9657 | 0.1142 | 0.112* | |
H14C | 0.6072 | 0.8128 | 0.1416 | 0.112* | |
C15 | 0.74350 (17) | 0.3815 (3) | 0.44129 (8) | 0.0685 (5) | |
H15A | 0.7383 | 0.4966 | 0.4226 | 0.103* | |
H15B | 0.7800 | 0.3869 | 0.4889 | 0.103* | |
H15C | 0.6573 | 0.3319 | 0.4339 | 0.103* | |
C16 | 0.8362 (2) | 0.0834 (3) | 0.43209 (10) | 0.0813 (6) | |
H16A | 0.7490 | 0.0372 | 0.4255 | 0.122* | |
H16B | 0.8768 | 0.0801 | 0.4793 | 0.122* | |
H16C | 0.8866 | 0.0149 | 0.4072 | 0.122* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0693 (3) | 0.0924 (4) | 0.0396 (2) | −0.0122 (2) | −0.00473 (17) | −0.0057 (2) |
O1 | 0.0577 (6) | 0.0468 (6) | 0.0350 (5) | −0.0092 (5) | 0.0030 (4) | 0.0070 (4) |
O2 | 0.0762 (8) | 0.0824 (9) | 0.0531 (7) | −0.0320 (7) | −0.0067 (6) | −0.0001 (6) |
O3 | 0.0486 (6) | 0.0729 (8) | 0.0846 (9) | −0.0020 (6) | 0.0258 (6) | 0.0254 (7) |
O4 | 0.0498 (6) | 0.0426 (5) | 0.0581 (6) | 0.0033 (4) | 0.0169 (5) | 0.0065 (5) |
C1 | 0.0446 (7) | 0.0631 (9) | 0.0370 (7) | −0.0032 (6) | 0.0127 (5) | 0.0018 (6) |
C2 | 0.0396 (7) | 0.0701 (10) | 0.0439 (7) | −0.0049 (7) | 0.0067 (6) | 0.0000 (7) |
C3 | 0.0495 (7) | 0.0482 (8) | 0.0343 (6) | −0.0006 (6) | 0.0015 (5) | −0.0007 (6) |
C4 | 0.0531 (8) | 0.0531 (8) | 0.0347 (6) | −0.0021 (6) | 0.0137 (6) | −0.0010 (6) |
C5 | 0.0416 (7) | 0.0468 (8) | 0.0391 (7) | −0.0037 (6) | 0.0120 (5) | −0.0007 (6) |
C6 | 0.0403 (6) | 0.0359 (6) | 0.0338 (6) | −0.0003 (5) | 0.0067 (5) | 0.0016 (5) |
C7 | 0.0396 (6) | 0.0408 (7) | 0.0326 (6) | 0.0016 (5) | 0.0095 (5) | 0.0020 (5) |
C8 | 0.0545 (8) | 0.0584 (9) | 0.0336 (7) | −0.0035 (7) | 0.0025 (6) | 0.0105 (6) |
C9 | 0.0478 (8) | 0.0663 (10) | 0.0393 (7) | 0.0017 (7) | 0.0009 (6) | 0.0076 (7) |
C10 | 0.0435 (7) | 0.0632 (9) | 0.0377 (7) | −0.0068 (7) | 0.0057 (6) | −0.0012 (6) |
C11 | 0.0382 (6) | 0.0442 (7) | 0.0347 (6) | −0.0014 (5) | 0.0075 (5) | 0.0008 (5) |
C12 | 0.0397 (7) | 0.0428 (7) | 0.0416 (7) | −0.0057 (6) | 0.0079 (5) | −0.0018 (6) |
C13 | 0.0657 (10) | 0.0389 (8) | 0.0749 (11) | 0.0025 (7) | 0.0134 (8) | 0.0102 (8) |
C14 | 0.0836 (13) | 0.0675 (12) | 0.0673 (11) | 0.0038 (10) | 0.0047 (10) | 0.0165 (9) |
C15 | 0.0616 (10) | 0.1026 (15) | 0.0442 (8) | 0.0000 (10) | 0.0179 (7) | 0.0050 (9) |
C16 | 0.0993 (15) | 0.0726 (13) | 0.0627 (11) | −0.0121 (11) | −0.0035 (10) | 0.0308 (10) |
Cl1—C3 | 1.7401 (13) | C8—C9 | 1.516 (2) |
O1—C7 | 1.3415 (16) | C8—C15 | 1.518 (2) |
O1—C8 | 1.4732 (16) | C9—C10 | 1.498 (2) |
O2—C10 | 1.2177 (19) | C9—H9A | 0.9700 |
O3—C12 | 1.1954 (17) | C9—H9B | 0.9700 |
O4—C12 | 1.3343 (17) | C10—C11 | 1.4622 (18) |
O4—C13 | 1.4571 (18) | C11—C12 | 1.4871 (19) |
C1—C2 | 1.3795 (19) | C13—C14 | 1.484 (3) |
C1—C6 | 1.3876 (19) | C13—H13A | 0.9700 |
C1—H1 | 0.9300 | C13—H13B | 0.9700 |
C2—C3 | 1.380 (2) | C14—H14A | 0.9600 |
C2—H2 | 0.9300 | C14—H14B | 0.9600 |
C3—C4 | 1.371 (2) | C14—H14C | 0.9600 |
C4—C5 | 1.3854 (18) | C15—H15A | 0.9600 |
C4—H4 | 0.9300 | C15—H15B | 0.9600 |
C5—C6 | 1.3866 (18) | C15—H15C | 0.9600 |
C5—H5 | 0.9300 | C16—H16A | 0.9600 |
C6—C7 | 1.4832 (16) | C16—H16B | 0.9600 |
C7—C11 | 1.3498 (18) | C16—H16C | 0.9600 |
C8—C16 | 1.515 (2) | ||
C7—O1—C8 | 118.01 (11) | H9A—C9—H9B | 107.9 |
C12—O4—C13 | 117.26 (11) | O2—C10—C11 | 123.09 (14) |
C2—C1—C6 | 120.99 (12) | O2—C10—C9 | 123.08 (13) |
C2—C1—H1 | 119.5 | C11—C10—C9 | 113.82 (13) |
C6—C1—H1 | 119.5 | C7—C11—C10 | 120.09 (12) |
C1—C2—C3 | 118.74 (13) | C7—C11—C12 | 121.88 (11) |
C1—C2—H2 | 120.6 | C10—C11—C12 | 117.96 (12) |
C3—C2—H2 | 120.6 | O3—C12—O4 | 124.04 (13) |
C4—C3—C2 | 121.41 (13) | O3—C12—C11 | 124.53 (13) |
C4—C3—Cl1 | 119.33 (11) | O4—C12—C11 | 111.43 (11) |
C2—C3—Cl1 | 119.24 (11) | O4—C13—C14 | 110.47 (14) |
C3—C4—C5 | 119.57 (12) | O4—C13—H13A | 109.6 |
C3—C4—H4 | 120.2 | C14—C13—H13A | 109.6 |
C5—C4—H4 | 120.2 | O4—C13—H13B | 109.6 |
C4—C5—C6 | 120.13 (12) | C14—C13—H13B | 109.6 |
C4—C5—H5 | 119.9 | H13A—C13—H13B | 108.1 |
C6—C5—H5 | 119.9 | C13—C14—H14A | 109.5 |
C5—C6—C1 | 119.15 (12) | C13—C14—H14B | 109.5 |
C5—C6—C7 | 120.20 (11) | H14A—C14—H14B | 109.5 |
C1—C6—C7 | 120.54 (11) | C13—C14—H14C | 109.5 |
O1—C7—C11 | 124.54 (11) | H14A—C14—H14C | 109.5 |
O1—C7—C6 | 110.78 (11) | H14B—C14—H14C | 109.5 |
C11—C7—C6 | 124.68 (11) | C8—C15—H15A | 109.5 |
O1—C8—C16 | 104.45 (13) | C8—C15—H15B | 109.5 |
O1—C8—C9 | 108.65 (11) | H15A—C15—H15B | 109.5 |
C16—C8—C9 | 111.84 (14) | C8—C15—H15C | 109.5 |
O1—C8—C15 | 107.56 (12) | H15A—C15—H15C | 109.5 |
C16—C8—C15 | 111.90 (15) | H15B—C15—H15C | 109.5 |
C9—C8—C15 | 112.02 (14) | C8—C16—H16A | 109.5 |
C10—C9—C8 | 111.96 (12) | C8—C16—H16B | 109.5 |
C10—C9—H9A | 109.2 | H16A—C16—H16B | 109.5 |
C8—C9—H9A | 109.2 | C8—C16—H16C | 109.5 |
C10—C9—H9B | 109.2 | H16A—C16—H16C | 109.5 |
C8—C9—H9B | 109.2 | H16B—C16—H16C | 109.5 |
C6—C1—C2—C3 | 1.2 (2) | C16—C8—C9—C10 | 169.65 (14) |
C1—C2—C3—C4 | −0.4 (2) | C15—C8—C9—C10 | −63.80 (16) |
C1—C2—C3—Cl1 | 177.82 (13) | C8—C9—C10—O2 | 141.88 (16) |
C2—C3—C4—C5 | −0.2 (2) | C8—C9—C10—C11 | −39.47 (18) |
Cl1—C3—C4—C5 | −178.35 (12) | O1—C7—C11—C10 | 7.7 (2) |
C3—C4—C5—C6 | −0.2 (2) | C6—C7—C11—C10 | −171.07 (12) |
C4—C5—C6—C1 | 1.0 (2) | O1—C7—C11—C12 | −175.43 (12) |
C4—C5—C6—C7 | 177.14 (13) | C6—C7—C11—C12 | 5.8 (2) |
C2—C1—C6—C5 | −1.6 (2) | O2—C10—C11—C7 | −173.28 (15) |
C2—C1—C6—C7 | −177.69 (14) | C9—C10—C11—C7 | 8.07 (19) |
C8—O1—C7—C11 | 10.50 (19) | O2—C10—C11—C12 | 9.8 (2) |
C8—O1—C7—C6 | −170.55 (11) | C9—C10—C11—C12 | −168.88 (13) |
C5—C6—C7—O1 | −128.38 (13) | C13—O4—C12—O3 | 2.3 (2) |
C1—C6—C7—O1 | 47.68 (17) | C13—O4—C12—C11 | −178.24 (12) |
C5—C6—C7—C11 | 50.56 (19) | C7—C11—C12—O3 | −115.07 (17) |
C1—C6—C7—C11 | −133.37 (15) | C10—C11—C12—O3 | 61.8 (2) |
C7—O1—C8—C16 | −160.72 (14) | C7—C11—C12—O4 | 65.43 (17) |
C7—O1—C8—C9 | −41.22 (17) | C10—C11—C12—O4 | −117.67 (13) |
C7—O1—C8—C15 | 80.23 (16) | C12—O4—C13—C14 | 91.59 (17) |
O1—C8—C9—C10 | 54.88 (17) |
Cg is the centroid of the C1–C6 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O4i | 0.93 | 2.66 | 3.3694 (18) | 134 |
C15—H15B···O2ii | 0.96 | 2.66 | 3.553 (2) | 156 |
C13—H13B···Cgiii | 0.97 | 2.96 | 3.6463 (17) | 129 |
Symmetry codes: (i) −x+1, y−1/2, −z+1/2; (ii) −x+2, −y+1, −z+1; (iii) x, y+1, z. |
Acknowledgements
The authors thank Professor D. Velmurugan, Head of Department, CAS in Crystallography and Biophysics, TBI X-ray Facility, University of Madras, India, for his kind help with the data collection and Professor A. Ilangovan, School of Chemistry, Bharathidasan University, Tiruchirappalli, Tamilnadu, India, for fruitful discussions.
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