(E)-3-(4-Eth­oxy­phen­yl)-1-(2-hy­droxy­phen­yl)prop-2-en-1-one

In the title compound, C₁₇H₁₆O₃, the carbonyl group is in an s-cis configuration with respect to the olefinic double bond. The dihedral angle between the two benzene rings is 2.85 (3)°. The prop-2-en-1-one bridge makes dihedral angles of 4.77 (4) and 4.15 (4)°, respectively, with the 2-hy­droxy­phenyl and 4-eth­oxy­phenyl rings. The eth­oxy group is coplanar with the attached phenyl ring [C_ar—O—C—C = 179.72 (5)°]. An intra­molecular O—H...O hydrogen bond generates an S(6) ring motif. In the crystal structure, mol­ecules are stacked in an anti­parallel manner to form columns along the b axis. The columnar structure is stabilized by C—H...π inter­actions involving the 2-hy­droxy­phenyl ring.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.041
• wR factor = 0.124
• Data-to-parameter ratio = 31.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT910_ALERT_3_C Missing # of FCF Reflections Below Th(Min) .....          1
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          3
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600         34

Alert level G
PLAT960_ALERT_3_G Number of Intensities with I .LT. - 2*sig(I) ..           4
PLAT154_ALERT_1_G The su's on the Cell Angles are Equal  (x 10000)        100 Deg.
PLAT720_ALERT_4_G Number of Unusual/Non-Standard Labels ..........          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   3 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   3 ALERT type 3 Indicator that the structure quality may be low
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Chalcones is an interesting class of compounds which have been reported to posses various useful properties such as non-linear optical (NLO) (Patil & Dharmaprakash, 2008) and fluorescent properties (Svetlichny et al., 2007). Synthetic and naturally occurring chalcones have been found to exhibit many useful biological activities, including anti-inflammatory, antileishmanial, antimicrobial, antioxidant (Nowakowska, 2007; Saydam et al., 2003), HIV-1 protease inhibitory (Tewtrakul et al., 2003) and tyrosinase inhibitory (Jun et al., 2007) activities. Our on going research on NLO properties and bioactivities of the synthetic chalcones led us to synthesize the title chalcone in order to study its NLO properties, antibacterial and tyrosinase inhibitory activities. The results show that the title compound, (I), crystallized in centrosymmetric P1 space group which prohibits the second order NLO properties. Our biological testing found that (I) was inactive against the tested bacteria which are Gram-positive bacteria i.e. Bacillus subtilis, Enterococcus faecalis, Staphylococcus aureus, Methicillin-Resistant Staphylococcus aureus and Vancomycin-Resistant Enterococcus faecalis and Gram-negative bacteria i.e. Pseudomonas aeruginosa, Salmonella typhi and Shigella sonnei. Nevertheless (I) shows moderate tyrosinase inhibitory activity which will be reported elsewhere with some other chalcones. Herein the crystal structure of (I) is reported.

The title molecule (Fig. 1) exists in an E configuration with respect to the C8═C9 ethenyl bond [1.3475 (8) Å]; the C7–C8–C9–C10 torsion angle is -178.73 (6)°. The molecule is almost planar with the dihedral angle between the 2-hydroxyphenyl and 4-ethoxyphenyl rings being 2.85 (3)°. The substituted ethoxy group is coplanar with the attached phenyl ring with the torsion angle C13–O3–C16–C17 = 179.72 (5)°. The prop-2-en-1-one unit (C7–C9/O1) is planar [r.m.s. deviation 0.0098 (1) Å] and the torsion angle O1–C7–C8–C9 being 3.15 (10)°. This bridge makes dihedral angles of 4.77 (4) and 4.15 (4)° with the 2-hydroxyphenyl and 4-ethoxyphenyl rings, respectively. Intramolecular O2—H1O2···O1 hydrogen bond generates an S(6) ring motif (Fig. 1) (Bernstein et al., 1995) which helps to stabilize the planarity of the chalcone skeleton. The bond distances are of normal values (Allen et al., 1987) and are comparable with those observed in related structures (Fun et al., 2008; Patil et al., 2007).

In the crystal packing, the molecules are stacked in an antiparallel manner into columns along the b axis (Fig. 2). This arrangement is stabilized by C—H···π interactions (Table 1) involving the hydroxy phenyl ring. In addition C···O short contacts [3.2894 (8)–3.4003 (9) Å] were also observed.

Related literature

For background on the applications of chalcones, see: Jun et al. (2007); Nowakowska (2007); Patil & Dharmaprakash (2008); Saydam et al. (2003); Svetlichny et al. (2007); Tewtrakul et al. (2003). For bond-length data, see: Allen et al. (1987). For hydrogen-bond motifs, see: Bernstein et al. (1995). For related structures, see: Fun et al. (2008); Patil et al. (2007). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

S2. Experimental

The title compound was synthesized by the condensation of 4-ethoxycarboxaldehyde (0.30 g, 2 mmol) with 2-hydroxyacetophenone (0.24 ml, 2 mmol) in ethanol (40 ml) in the presence of 30% aqueous NaOH (5 ml) at room temperature. After stirring for 3 h, 20% H₂SO₄(aq) (5 ml) was added dropwise into the solution. After the reaction mixture was kept at room temperature for a day, a yellow solid appeared and was then collected by filtration, washed with acetone and dried in air. Yellow block-shaped single crystals of the title compound suitable for X-ray structure determination were recrystalized from acetone by slow evaporation of the solvent at room temperature after several days (m.p. 387–388 K).

S3. Refinement

Hydroxyl H atom was located in a difference map and refined isotropically. The remaining H atoms were placed in calculated positions, with C–H = 0.93 Å, U_iso = 1.2U_eq(C) for aromatic and CH, C–H = 0.96 Å, U_iso = 1.2U_eq(C) for CH₂, and C–H = 0.97 Å, U_iso = 1.5U_eq(C) for CH₃ atoms. A rotating group model was used for the methyl groups.

Computing details

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures

	Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Intramolecular O—H···O hydrogen bond is shown as a dashed line.
	Fig. 2. The crystal packing of the title compound viewed along the a axis, showing antiparallel stacked columns running along the b axis.

(E)-3-(4-Ethoxyphenyl)-1-(2-hydroxyphenyl)prop-2-en-1-one

Crystal data

C17H16O3	Z = 2
Mr = 268.30	F(000) = 284
Triclinic, P1	Dx = 1.330 Mg m^−3
Hall symbol: -P 1	Melting point = 387–388 K
a = 6.8305 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 6.8790 (2) Å	Cell parameters from 5849 reflections
c = 14.8188 (3) Å	θ = 1.4–35.0°
α = 88.533 (1)°	µ = 0.09 mm^−1
β = 80.380 (1)°	T = 100 K
γ = 77.469 (1)°	Block, yellow
V = 670.11 (3) Å^3	0.60 × 0.38 × 0.36 mm

Data collection

Bruker APEXII CCD area-detector diffractometer	5849 independent reflections
Radiation source: sealed tube	5179 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
φ and ω scans	θmax = 35.0°, θmin = 1.4°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −11→11
Tmin = 0.948, Tmax = 0.969	k = −10→11
24772 measured reflections	l = −23→23

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.124	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0744P)^2 + 0.1118P] where P = (Fo^2 + 2Fc^2)/3
5848 reflections	(Δ/σ)max = 0.001
186 parameters	Δρmax = 0.39 e Å^−3
0 restraints	Δρmin = −0.44 e Å^−3

Special details

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	1.46060 (7)	0.63044 (8)	0.13054 (3)	0.01858 (10)
O2	1.59166 (7)	0.61854 (8)	0.27959 (4)	0.01890 (11)
H1O2	1.589 (2)	0.614 (2)	0.2173 (11)	0.052 (4)*
O3	0.61756 (7)	0.84310 (8)	−0.23045 (3)	0.01749 (10)
C1	1.39580 (9)	0.65747 (9)	0.32040 (4)	0.01353 (11)
C2	1.35615 (10)	0.66707 (10)	0.41620 (4)	0.01724 (12)
H2A	1.4636	0.6474	0.4490	0.021*
C3	1.15843 (11)	0.70553 (11)	0.46221 (5)	0.02141 (13)
H3A	1.1333	0.7123	0.5258	0.026*
C4	0.99566 (11)	0.73437 (12)	0.41364 (5)	0.02221 (14)
H4A	0.8626	0.7594	0.4448	0.027*
C5	1.03359 (10)	0.72550 (10)	0.31877 (4)	0.01683 (12)
H5A	0.9248	0.7447	0.2869	0.020*
C6	1.23305 (9)	0.68816 (9)	0.26988 (4)	0.01237 (10)
C7	1.27920 (9)	0.67709 (9)	0.16865 (4)	0.01267 (10)
C8	1.11547 (9)	0.72198 (9)	0.11403 (4)	0.01350 (11)
H8A	0.9811	0.7630	0.1425	0.016*
C9	1.16056 (9)	0.70358 (9)	0.02217 (4)	0.01346 (11)
H9A	1.2972	0.6595	−0.0024	0.016*
C10	1.01927 (9)	0.74506 (9)	−0.04275 (4)	0.01229 (10)
C11	0.80665 (9)	0.79158 (9)	−0.01582 (4)	0.01357 (11)
H11A	0.7517	0.7999	0.0461	0.016*
C12	0.67867 (9)	0.82501 (9)	−0.08002 (4)	0.01398 (11)
H12A	0.5386	0.8566	−0.0611	0.017*
C13	0.75873 (9)	0.81164 (9)	−0.17369 (4)	0.01315 (10)
C14	0.96900 (9)	0.76806 (10)	−0.20234 (4)	0.01477 (11)
H14A	1.0233	0.7606	−0.2643	0.018*
C15	1.09656 (9)	0.73581 (9)	−0.13654 (4)	0.01429 (11)
H15A	1.2367	0.7074	−0.1555	0.017*
C16	0.68663 (9)	0.83005 (9)	−0.32736 (4)	0.01484 (11)
H16A	0.7685	0.6985	−0.3445	0.018*
H16B	0.7680	0.9278	−0.3465	0.018*
C17	0.49767 (11)	0.87050 (11)	−0.37121 (5)	0.01895 (12)
H17A	0.5358	0.8690	−0.4366	0.028*
H17B	0.4155	0.9986	−0.3514	0.028*
H17C	0.4217	0.7696	−0.3536	0.028*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.01206 (19)	0.0280 (3)	0.0151 (2)	−0.00354 (17)	−0.00144 (15)	−0.00028 (17)
O2	0.01199 (19)	0.0265 (2)	0.0186 (2)	−0.00291 (17)	−0.00501 (16)	−0.00171 (18)
O3	0.01373 (19)	0.0271 (3)	0.01164 (19)	−0.00273 (17)	−0.00437 (14)	0.00013 (16)
C1	0.0135 (2)	0.0129 (2)	0.0151 (2)	−0.00301 (18)	−0.00482 (18)	0.00005 (18)
C2	0.0209 (3)	0.0179 (3)	0.0145 (2)	−0.0041 (2)	−0.0076 (2)	0.00091 (19)
C3	0.0244 (3)	0.0268 (3)	0.0130 (2)	−0.0054 (2)	−0.0034 (2)	0.0009 (2)
C4	0.0174 (3)	0.0329 (4)	0.0149 (3)	−0.0044 (2)	−0.0001 (2)	0.0007 (2)
C5	0.0130 (2)	0.0228 (3)	0.0145 (2)	−0.0035 (2)	−0.00232 (19)	0.0006 (2)
C6	0.0120 (2)	0.0133 (2)	0.0122 (2)	−0.00281 (17)	−0.00315 (17)	0.00025 (17)
C7	0.0127 (2)	0.0131 (2)	0.0129 (2)	−0.00335 (17)	−0.00318 (17)	0.00039 (17)
C8	0.0128 (2)	0.0150 (2)	0.0130 (2)	−0.00247 (18)	−0.00374 (18)	−0.00015 (18)
C9	0.0138 (2)	0.0146 (2)	0.0129 (2)	−0.00401 (18)	−0.00363 (17)	0.00107 (18)
C10	0.0129 (2)	0.0128 (2)	0.0116 (2)	−0.00302 (17)	−0.00291 (17)	0.00046 (17)
C11	0.0136 (2)	0.0159 (2)	0.0113 (2)	−0.00358 (18)	−0.00181 (17)	0.00037 (17)
C12	0.0124 (2)	0.0167 (2)	0.0125 (2)	−0.00295 (18)	−0.00149 (17)	−0.00021 (18)
C13	0.0127 (2)	0.0145 (2)	0.0126 (2)	−0.00236 (18)	−0.00379 (17)	0.00019 (18)
C14	0.0134 (2)	0.0191 (3)	0.0111 (2)	−0.00229 (19)	−0.00181 (17)	−0.00019 (18)
C15	0.0122 (2)	0.0177 (3)	0.0124 (2)	−0.00208 (18)	−0.00191 (17)	−0.00048 (18)
C16	0.0169 (2)	0.0151 (2)	0.0129 (2)	−0.00269 (19)	−0.00430 (18)	0.00006 (18)
C17	0.0206 (3)	0.0204 (3)	0.0173 (3)	−0.0031 (2)	−0.0091 (2)	0.0003 (2)

Geometric parameters (Å, º)

O1—C7	1.2491 (7)	C9—C10	1.4543 (8)
O2—C1	1.3452 (8)	C9—H9A	0.93
O2—H1O2	0.928 (16)	C10—C15	1.3998 (8)
O3—C13	1.3621 (7)	C10—C11	1.4078 (8)
O3—C16	1.4334 (7)	C11—C12	1.3791 (8)
C1—C2	1.4006 (9)	C11—H11A	0.93
C1—C6	1.4174 (8)	C12—C13	1.4019 (8)
C2—C3	1.3803 (10)	C12—H12A	0.93
C2—H2A	0.93	C13—C14	1.3960 (8)
C3—C4	1.3993 (10)	C14—C15	1.3957 (8)
C3—H3A	0.93	C14—H14A	0.93
C4—C5	1.3868 (9)	C15—H15A	0.93
C4—H4A	0.93	C16—C17	1.5102 (9)
C5—C6	1.4053 (8)	C16—H16A	0.97
C5—H5A	0.93	C16—H16B	0.97
C6—C7	1.4808 (8)	C17—H17A	0.96
C7—C8	1.4632 (8)	C17—H17B	0.96
C8—C9	1.3475 (8)	C17—H17C	0.96
C8—H8A	0.93
C1—O2—H1O2	105.5 (10)	C15—C10—C9	118.97 (5)
C13—O3—C16	118.56 (5)	C11—C10—C9	123.04 (5)
O2—C1—C2	117.49 (5)	C12—C11—C10	120.91 (5)
O2—C1—C6	122.28 (5)	C12—C11—H11A	119.5
C2—C1—C6	120.23 (6)	C10—C11—H11A	119.5
C3—C2—C1	120.32 (6)	C11—C12—C13	120.33 (5)
C3—C2—H2A	119.8	C11—C12—H12A	119.8
C1—C2—H2A	119.8	C13—C12—H12A	119.8
C2—C3—C4	120.34 (6)	O3—C13—C14	125.05 (5)
C2—C3—H3A	119.8	O3—C13—C12	114.98 (5)
C4—C3—H3A	119.8	C14—C13—C12	119.97 (5)
C5—C4—C3	119.71 (6)	C15—C14—C13	119.03 (5)
C5—C4—H4A	120.1	C15—C14—H14A	120.5
C3—C4—H4A	120.1	C13—C14—H14A	120.5
C4—C5—C6	121.34 (6)	C14—C15—C10	121.76 (5)
C4—C5—H5A	119.3	C14—C15—H15A	119.1
C6—C5—H5A	119.3	C10—C15—H15A	119.1
C5—C6—C1	118.06 (5)	O3—C16—C17	106.17 (5)
C5—C6—C7	122.80 (5)	O3—C16—H16A	110.5
C1—C6—C7	119.14 (5)	C17—C16—H16A	110.5
O1—C7—C8	120.46 (5)	O3—C16—H16B	110.5
O1—C7—C6	118.86 (5)	C17—C16—H16B	110.5
C8—C7—C6	120.67 (5)	H16A—C16—H16B	108.7
C9—C8—C7	119.61 (5)	C16—C17—H17A	109.5
C9—C8—H8A	120.2	C16—C17—H17B	109.5
C7—C8—H8A	120.2	H17A—C17—H17B	109.5
C8—C9—C10	127.21 (5)	C16—C17—H17C	109.5
C8—C9—H9A	116.4	H17A—C17—H17C	109.5
C10—C9—H9A	116.4	H17B—C17—H17C	109.5
C15—C10—C11	117.98 (5)
O2—C1—C2—C3	−179.69 (6)	C7—C8—C9—C10	−178.73 (5)
C6—C1—C2—C3	0.31 (10)	C8—C9—C10—C15	173.80 (6)
C1—C2—C3—C4	0.31 (11)	C8—C9—C10—C11	−7.18 (10)
C2—C3—C4—C5	−0.43 (12)	C15—C10—C11—C12	0.63 (9)
C3—C4—C5—C6	−0.06 (11)	C9—C10—C11—C12	−178.39 (5)
C4—C5—C6—C1	0.65 (10)	C10—C11—C12—C13	0.49 (9)
C4—C5—C6—C7	179.82 (6)	C16—O3—C13—C14	0.40 (9)
O2—C1—C6—C5	179.22 (6)	C16—O3—C13—C12	−179.35 (5)
C2—C1—C6—C5	−0.78 (9)	C11—C12—C13—O3	178.52 (5)
O2—C1—C6—C7	0.03 (9)	C11—C12—C13—C14	−1.24 (9)
C2—C1—C6—C7	−179.97 (5)	O3—C13—C14—C15	−178.90 (6)
C5—C6—C7—O1	−175.37 (6)	C12—C13—C14—C15	0.83 (9)
C1—C6—C7—O1	3.79 (9)	C13—C14—C15—C10	0.32 (10)
C5—C6—C7—C8	5.26 (9)	C11—C10—C15—C14	−1.04 (9)
C1—C6—C7—C8	−175.59 (5)	C9—C10—C15—C14	178.03 (6)
O1—C7—C8—C9	3.15 (9)	C13—O3—C16—C17	179.71 (5)
C6—C7—C8—C9	−177.48 (5)

Hydrogen-bond geometry (Å, º)

Cg1 is the centroid of the O2,C1–C6 ring?

D—H···A	D—H	H···A	D···A	D—H···A
O2—H1O2···O1	0.93 (2)	1.66 (2)	2.5113 (7)	151 (1)
C16—H16A···Cg1^i	0.97	2.70	3.5762 (7)	151
C16—H16B···Cg1^ii	0.97	2.66	3.5339 (7)	151

Symmetry codes: (i) −x+2, −y+1, −z; (ii) −x+2, −y+2, −z.