organic compounds
(E)-2-(3,5-Dimethoxybenzylidene)indan-1-one
aSchool of Science and Technology, H-3209, Georgia Gwinnett College, 1000 University Center Lane, Lawrenceville, GA 30043, USA, and bNorth Carolina State University, Molecular Education, Technology, and Research Innovation Center, 2620 Yarbrough Dr., Raleigh, NC 27695, USA
*Correspondence e-mail: jsloop@ggc.edu
The title chalcone, C18H16O3, was prepared by a solventless base-promoted Claisen–Schmidt condensation and, upon recrystallization from ethanol, obtained in 56% yield. The dihedral angle between the indanone ring system and the benzene ring is 2.54 (4) ° and the C atoms of the methoxy groups deviate from the benzene ring by 0.087 (1) and 0.114 (1) Å. In the crystal, π-stacking is the predominant intermolecular force, with the molecules stacking into columns running parallel to the b axis of the unit cell.
Keywords: crystal structure; green synthesis; indanone; chalcone.
CCDC reference: 1894469
Structure description
The chalcone family of compounds possess an aromatic α,β-unsaturated ketone functionality and can readily be formed by base-promoted condensation–dehydrations of an aromatic aldehyde and an aromatic ketone. They are important pharmacophore scaffolds and can possess anti-inflammatory, anti-fungal, anti-cancer, and anti-malarial biological activities (Singh et al., 2015, 2014; Berthelette et al., 1997). Additionally, the aromatic groups can be functionalized so as to produce other biological effects. The indanone family of compounds are biologically active compounds that are involved in steroid hormone biosynthesis and arachidonic acid metabolism pathways (Berthelette et al., 1997). In addition, indanone derivatives serve as scaffolds for a variety of heterocycles (Sloop et al., 2002, 2012).
The combination of these two potential pharmacophores using greener and more efficient synthesis pathways en route to a series of highly functionalized indanone-based minimizes reaction toxicity, limits waste production and enables easier product isolation in many cases.
is now being studied by our research group. The solvent-free Claisen–Schmidt reaction undertaken in Fig. 1In the title molecule (Fig. 2), the dihedral angle between the indanone ring system and the benzene ring is 2.54 (4) ° and the C`7 and C18 atoms of the methoxy groups deviate from the benzene ring by 0.087 (1) and 0.114 (1) Å, respectively. No unusual bond lengths or angles are noted after a routine Mogul geometry check (Bruno et al., 2004).
The predominant supramolecular feature of this structure (Fig. 3) are slipped stacking interactions. This consists of ring-over-atom pairings between the indanone ring and the 3-position of the dimethoxyphenyl ring of a neighboring molecule and generates a relatively close contact of 2.7 Å for the methylene H atoms of the indanone ring to the adjacent molecule.
Structurally characterized 1b is consistent with known structures of similar indaneones. A search of the Cambridge Structural Database (Version 5.41, update of November 2019; Groom et al., 2016) gave 35 hits with a similar core structure. A defined three-dimensional parameter search on the distance between the carbonyl O atom and the phenyl ring gave a clear indication of the stereochemistry of the double bond. The title compound adopts the more common E isomer – along with 33 of the other structures published – indicated by an O—C distances 4.2 to 4.5 Å. Only two examples of Z isomers (O—C of 3.2 to 3.4 Å) exist [POWZUX (Zhou et al., 2009) and HAVLAR (Mori & Maeda, 1994)]. The latter has seven structure determinations as part of a light-driven solid-state isomerization study (Harada et al., 2009).
Synthesis and crystallization
A 25 mL beaker equipped with a stir bar was charged with 3,5-dimethoxybenzaldehyde (0.50 g, 3.0 mmol) and warmed to 60°C. To the liquified aldehyde was added 1-indanone (0.40 g, 3.0 mmol) and solid NaOH (0.20 g, 3.8 mmol). The reaction mixture was stirred for 30 minutes at 60°C. The resulting reaction mixture was neutralized with 4 mL of 1 M HCl, the resulting residue was washed with several 1 mL aliquots of distilled water and the crude product (0.80 g, 95% yield) isolated via vacuum filtration. Recrystallization from 95% ethanol solution via slow evaporation afforded the target chalcone, (E)-2-(3,5-dimethoxybenzylidenyl)-1-indanone (1b) as colorless needles, (0.47 g, 56% yield). Melting range: 174–175°C. IR, 1H and 13C NMR spectroscopy and single-crystal X-ray analysis (see supporting information) confirmed the product identity.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 1Structural data
CCDC reference: 1894469
https://doi.org/10.1107/S2414314620007592/bt4094sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620007592/bt4094Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2414314620007592/bt4094Isup3.smi
Supporting information file. DOI: https://doi.org/10.1107/S2414314620007592/bt4094Isup4.cml
1H NMR data. DOI: https://doi.org/10.1107/S2414314620007592/bt4094sup5.pdf
13C NMR data. DOI: https://doi.org/10.1107/S2414314620007592/bt4094sup6.pdf
Data collection: Instrument Service (Bruker, 2017); cell
APEX3 (Bruker, 2017); data reduction: SAINT (Bruker, 2017); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2020); software used to prepare material for publication: publCIF (Westrip, 2010).C18H16O3 | F(000) = 592 |
Mr = 280.31 | Dx = 1.372 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 7.7611 (4) Å | Cell parameters from 242 reflections |
b = 7.2894 (4) Å | θ = 3.0–33.1° |
c = 24.0331 (13) Å | µ = 0.09 mm−1 |
β = 93.5573 (12)° | T = 100 K |
V = 1357.02 (13) Å3 | Needle, colourless |
Z = 4 | 0.39 × 0.12 × 0.05 mm |
Bruker-Nonius X8 Kappa APEXII diffractometer | 5231 independent reflections |
Radiation source: fine-focus sealed tube | 4087 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.040 |
Detector resolution: 8.3333 pixels mm-1 | θmax = 33.3°, θmin = 2.6° |
phi and ω scans | h = −11→11 |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | k = −11→11 |
Tmin = 0.95, Tmax = 0.99 | l = −37→37 |
30838 measured reflections |
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)] = 0.044 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.123 | H-atom parameters constrained |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0695P)2 + 0.2851P] where P = (Fo2 + 2Fc2)/3 |
5231 reflections | (Δ/σ)max = 0.001 |
192 parameters | Δρmax = 0.61 e Å−3 |
0 restraints | Δρmin = −0.24 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. |
Refinement. All hydrogen atoms were seen in the difference map of later refinements, but were placed at calculated positions and refined using a riding model, setting isotropic displacement parameters to 1.2 or 1.5 times that of the parent atom for ring H atoms and methyl groups respectively. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.47855 (9) | 0.17474 (11) | 0.33135 (3) | 0.01698 (15) | |
O2 | 1.03362 (8) | 0.10918 (10) | 0.58143 (3) | 0.01475 (14) | |
O3 | 0.48827 (9) | 0.32457 (10) | 0.64602 (3) | 0.01472 (14) | |
C1 | 0.37431 (12) | 0.23058 (12) | 0.36368 (4) | 0.01126 (16) | |
C2 | 0.40164 (11) | 0.24728 (12) | 0.42550 (4) | 0.01007 (15) | |
C3 | 0.23699 (11) | 0.31671 (12) | 0.44870 (4) | 0.01069 (16) | |
H3A | 0.191109 | 0.227118 | 0.474981 | 0.013* | |
H3B | 0.256199 | 0.435489 | 0.468075 | 0.013* | |
C4 | 0.11611 (11) | 0.33843 (12) | 0.39744 (4) | 0.01048 (16) | |
C5 | 0.19615 (12) | 0.29325 (12) | 0.34906 (4) | 0.01129 (16) | |
C6 | 0.11094 (12) | 0.30860 (13) | 0.29642 (4) | 0.01457 (18) | |
H6 | 0.168019 | 0.279979 | 0.263676 | 0.017* | |
C7 | −0.05951 (13) | 0.36685 (14) | 0.29328 (4) | 0.01710 (19) | |
H7 | −0.120329 | 0.378944 | 0.257935 | 0.021* | |
C8 | −0.14259 (12) | 0.40795 (13) | 0.34182 (4) | 0.01618 (18) | |
H8 | −0.260325 | 0.444422 | 0.339062 | 0.019* | |
C9 | −0.05538 (12) | 0.39621 (12) | 0.39403 (4) | 0.01333 (17) | |
H9 | −0.111664 | 0.427002 | 0.426756 | 0.016* | |
C10 | 0.55633 (12) | 0.20333 (12) | 0.44993 (4) | 0.01049 (16) | |
H10 | 0.63798 | 0.160868 | 0.425033 | 0.013* | |
C11 | 0.62038 (11) | 0.20978 (12) | 0.50842 (4) | 0.00944 (15) | |
C12 | 0.79305 (11) | 0.15891 (12) | 0.52012 (4) | 0.01034 (15) | |
H12 | 0.86179 | 0.122965 | 0.490626 | 0.012* | |
C13 | 0.86425 (11) | 0.16081 (12) | 0.57468 (4) | 0.01032 (15) | |
C14 | 0.76564 (11) | 0.21385 (12) | 0.61855 (4) | 0.01067 (16) | |
H14 | 0.813948 | 0.214673 | 0.655848 | 0.013* | |
C15 | 0.59412 (11) | 0.26573 (12) | 0.60630 (4) | 0.01004 (15) | |
C16 | 0.52038 (11) | 0.26358 (12) | 0.55215 (4) | 0.01045 (15) | |
H16 | 0.40318 | 0.298291 | 0.544834 | 0.013* | |
C17 | 1.10933 (12) | 0.09692 (13) | 0.63704 (4) | 0.01411 (17) | |
H17A | 1.229061 | 0.054895 | 0.636091 | 0.021* | |
H17B | 1.043717 | 0.009564 | 0.658384 | 0.021* | |
H17C | 1.107152 | 0.217881 | 0.654776 | 0.021* | |
C18 | 0.54517 (13) | 0.30032 (15) | 0.70314 (4) | 0.01596 (18) | |
H18A | 0.57173 | 0.170604 | 0.710108 | 0.024* | |
H18B | 0.453887 | 0.339485 | 0.726921 | 0.024* | |
H18C | 0.648975 | 0.374224 | 0.711613 | 0.024* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0152 (3) | 0.0258 (4) | 0.0101 (3) | 0.0022 (3) | 0.0025 (2) | −0.0029 (3) |
O2 | 0.0093 (3) | 0.0234 (3) | 0.0114 (3) | 0.0048 (2) | −0.0004 (2) | −0.0017 (2) |
O3 | 0.0125 (3) | 0.0249 (4) | 0.0069 (3) | 0.0053 (3) | 0.0018 (2) | −0.0017 (2) |
C1 | 0.0120 (4) | 0.0128 (4) | 0.0089 (4) | −0.0009 (3) | 0.0004 (3) | −0.0003 (3) |
C2 | 0.0117 (4) | 0.0111 (4) | 0.0074 (3) | −0.0006 (3) | 0.0009 (3) | −0.0002 (3) |
C3 | 0.0112 (4) | 0.0120 (4) | 0.0090 (3) | 0.0004 (3) | 0.0015 (3) | −0.0008 (3) |
C4 | 0.0108 (4) | 0.0096 (3) | 0.0110 (4) | −0.0010 (3) | 0.0002 (3) | 0.0002 (3) |
C5 | 0.0119 (4) | 0.0119 (4) | 0.0099 (4) | −0.0007 (3) | −0.0007 (3) | 0.0004 (3) |
C6 | 0.0155 (4) | 0.0170 (4) | 0.0109 (4) | −0.0010 (3) | −0.0017 (3) | 0.0006 (3) |
C7 | 0.0164 (4) | 0.0177 (4) | 0.0165 (4) | −0.0009 (3) | −0.0053 (3) | 0.0025 (3) |
C8 | 0.0121 (4) | 0.0142 (4) | 0.0218 (5) | 0.0007 (3) | −0.0021 (3) | 0.0023 (3) |
C9 | 0.0116 (4) | 0.0126 (4) | 0.0159 (4) | 0.0006 (3) | 0.0012 (3) | 0.0014 (3) |
C10 | 0.0117 (4) | 0.0116 (4) | 0.0083 (3) | 0.0002 (3) | 0.0012 (3) | −0.0007 (3) |
C11 | 0.0100 (4) | 0.0097 (3) | 0.0086 (3) | −0.0002 (3) | 0.0006 (3) | −0.0004 (3) |
C12 | 0.0110 (4) | 0.0116 (4) | 0.0086 (3) | 0.0012 (3) | 0.0016 (3) | −0.0005 (3) |
C13 | 0.0089 (4) | 0.0112 (4) | 0.0109 (4) | 0.0009 (3) | 0.0007 (3) | −0.0002 (3) |
C14 | 0.0103 (4) | 0.0125 (4) | 0.0092 (4) | 0.0011 (3) | 0.0004 (3) | −0.0005 (3) |
C15 | 0.0101 (4) | 0.0121 (4) | 0.0080 (4) | 0.0006 (3) | 0.0017 (3) | −0.0010 (3) |
C16 | 0.0094 (4) | 0.0127 (4) | 0.0093 (4) | 0.0011 (3) | 0.0003 (3) | −0.0004 (3) |
C17 | 0.0123 (4) | 0.0165 (4) | 0.0132 (4) | 0.0014 (3) | −0.0025 (3) | −0.0011 (3) |
C18 | 0.0172 (4) | 0.0238 (5) | 0.0071 (4) | 0.0020 (3) | 0.0022 (3) | −0.0007 (3) |
O1—C1 | 1.2255 (11) | C8—H8 | 0.95 |
O2—C13 | 1.3673 (11) | C9—H9 | 0.95 |
O2—C17 | 1.4289 (11) | C10—C11 | 1.4623 (12) |
O3—C15 | 1.3665 (11) | C10—H10 | 0.95 |
O3—C18 | 1.4267 (11) | C11—C16 | 1.4006 (12) |
C1—C5 | 1.4777 (13) | C11—C12 | 1.4020 (12) |
C1—C2 | 1.4929 (12) | C12—C13 | 1.3912 (12) |
C2—C10 | 1.3421 (12) | C12—H12 | 0.95 |
C2—C3 | 1.5127 (13) | C13—C14 | 1.3952 (12) |
C3—C4 | 1.5098 (13) | C14—C15 | 1.3975 (12) |
C3—H3A | 0.99 | C14—H14 | 0.95 |
C3—H3B | 0.99 | C15—C16 | 1.3890 (12) |
C4—C5 | 1.3913 (12) | C16—H16 | 0.95 |
C4—C9 | 1.3935 (12) | C17—H17A | 0.98 |
C5—C6 | 1.3951 (12) | C17—H17B | 0.98 |
C6—C7 | 1.3869 (14) | C17—H17C | 0.98 |
C6—H6 | 0.95 | C18—H18A | 0.98 |
C7—C8 | 1.3999 (15) | C18—H18B | 0.98 |
C7—H7 | 0.95 | C18—H18C | 0.98 |
C8—C9 | 1.3908 (13) | ||
C13—O2—C17 | 117.69 (7) | C2—C10—H10 | 114.6 |
C15—O3—C18 | 118.00 (7) | C11—C10—H10 | 114.6 |
O1—C1—C5 | 126.64 (8) | C16—C11—C12 | 119.40 (8) |
O1—C1—C2 | 126.83 (8) | C16—C11—C10 | 123.99 (8) |
C5—C1—C2 | 106.53 (7) | C12—C11—C10 | 116.61 (8) |
C10—C2—C1 | 118.94 (8) | C13—C12—C11 | 120.34 (8) |
C10—C2—C3 | 132.21 (8) | C13—C12—H12 | 119.8 |
C1—C2—C3 | 108.84 (7) | C11—C12—H12 | 119.8 |
C4—C3—C2 | 103.34 (7) | O2—C13—C12 | 115.58 (8) |
C4—C3—H3A | 111.1 | O2—C13—C14 | 123.71 (8) |
C2—C3—H3A | 111.1 | C12—C13—C14 | 120.70 (8) |
C4—C3—H3B | 111.1 | C13—C14—C15 | 118.42 (8) |
C2—C3—H3B | 111.1 | C13—C14—H14 | 120.8 |
H3A—C3—H3B | 109.1 | C15—C14—H14 | 120.8 |
C5—C4—C9 | 119.79 (8) | O3—C15—C16 | 115.30 (8) |
C5—C4—C3 | 111.71 (8) | O3—C15—C14 | 122.96 (8) |
C9—C4—C3 | 128.50 (8) | C16—C15—C14 | 121.73 (8) |
C4—C5—C6 | 121.84 (8) | C15—C16—C11 | 119.40 (8) |
C4—C5—C1 | 109.53 (8) | C15—C16—H16 | 120.3 |
C6—C5—C1 | 128.63 (8) | C11—C16—H16 | 120.3 |
C7—C6—C5 | 118.09 (9) | O2—C17—H17A | 109.5 |
C7—C6—H6 | 121.0 | O2—C17—H17B | 109.5 |
C5—C6—H6 | 121.0 | H17A—C17—H17B | 109.5 |
C6—C7—C8 | 120.48 (9) | O2—C17—H17C | 109.5 |
C6—C7—H7 | 119.8 | H17A—C17—H17C | 109.5 |
C8—C7—H7 | 119.8 | H17B—C17—H17C | 109.5 |
C9—C8—C7 | 121.00 (9) | O3—C18—H18A | 109.5 |
C9—C8—H8 | 119.5 | O3—C18—H18B | 109.5 |
C7—C8—H8 | 119.5 | H18A—C18—H18B | 109.5 |
C8—C9—C4 | 118.77 (9) | O3—C18—H18C | 109.5 |
C8—C9—H9 | 120.6 | H18A—C18—H18C | 109.5 |
C4—C9—H9 | 120.6 | H18B—C18—H18C | 109.5 |
C2—C10—C11 | 130.87 (8) | ||
O1—C1—C2—C10 | 2.20 (14) | C3—C4—C9—C8 | 179.35 (9) |
C5—C1—C2—C10 | −178.24 (8) | C1—C2—C10—C11 | 178.55 (9) |
O1—C1—C2—C3 | −178.27 (9) | C3—C2—C10—C11 | −0.85 (17) |
C5—C1—C2—C3 | 1.28 (9) | C2—C10—C11—C16 | 1.67 (15) |
C10—C2—C3—C4 | 179.41 (10) | C2—C10—C11—C12 | −178.08 (9) |
C1—C2—C3—C4 | −0.03 (9) | C16—C11—C12—C13 | 0.36 (13) |
C2—C3—C4—C5 | −1.36 (9) | C10—C11—C12—C13 | −179.87 (8) |
C2—C3—C4—C9 | 179.02 (9) | C17—O2—C13—C12 | −175.86 (8) |
C9—C4—C5—C6 | 1.74 (14) | C17—O2—C13—C14 | 4.54 (13) |
C3—C4—C5—C6 | −177.92 (8) | C11—C12—C13—O2 | −179.86 (8) |
C9—C4—C5—C1 | −178.10 (8) | C11—C12—C13—C14 | −0.25 (13) |
C3—C4—C5—C1 | 2.24 (10) | O2—C13—C14—C15 | 179.29 (8) |
O1—C1—C5—C4 | 177.40 (9) | C12—C13—C14—C15 | −0.29 (13) |
C2—C1—C5—C4 | −2.16 (10) | C18—O3—C15—C16 | 169.35 (8) |
O1—C1—C5—C6 | −2.42 (16) | C18—O3—C15—C14 | −11.69 (13) |
C2—C1—C5—C6 | 178.02 (9) | C13—C14—C15—O3 | −178.18 (8) |
C4—C5—C6—C7 | −1.47 (14) | C13—C14—C15—C16 | 0.72 (13) |
C1—C5—C6—C7 | 178.33 (9) | O3—C15—C16—C11 | 178.37 (8) |
C5—C6—C7—C8 | −0.26 (14) | C14—C15—C16—C11 | −0.61 (13) |
C6—C7—C8—C9 | 1.73 (15) | C12—C11—C16—C15 | 0.06 (13) |
C7—C8—C9—C4 | −1.46 (14) | C10—C11—C16—C15 | −179.69 (8) |
C5—C4—C9—C8 | −0.24 (13) |
Acknowledgements
All X-ray crystallography measurements were made in the Molecular Education, Technology, and Research Innovation Center (METRIC) at North Carolina State University.
Funding information
Funding for this research was provided by: GGC STEC 4500 Research Fund.
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