1-(4-Fluoro­phen­yl)-3-(4-methoxy­phen­yl)prop-2-en-1-one

Harrison, W.T.A.; Yathirajan, H.S.; Anilkumar, H.G.; Sarojini, B.K.; Narayana, B.

doi:10.1107/S160053680602530X

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 8| August 2006| Pages o3251-o3253

https://doi.org/10.1107/S160053680602530X

1-(4-Fluorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one

William T. A. Harrison,^a ^* H. S. Yathirajan,^b H. G. Anilkumar,^b B. K. Sarojini ^c and B. Narayana ^d

^aDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland, ^bDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, ^cDepartment of Chemistry, P. A. College of Engineering, Nadupadavu, Mangalore 574 153, India, and ^dDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, India
^*Correspondence e-mail: w.harrison@abdn.ac.uk

(Received 27 June 2006; accepted 30 June 2006; online 12 July 2006)

The planar molecules of the title compound, C₁₅H₁₃FO₂, are normal. The non-centrosymmetric crystal packing may be influenced by weak C—H⋯O and C—H⋯F interactions.

Comment

Among the various organic compounds reported for their non-linear optical (NLO) properties, chalcone derivatives are notable for their excellent blue-light transmittance and good crystallizability (Uchida et al., 1998 ). They provide a necessary molecular electronic configuration to show NLO effects, with two aromatic rings connected through a conjugated bridge (Goto et al., 1991 ; Tam et al., 1989 ; Indira et al., 2002 ). Substitution on either of the benzene rings appears to increase the likelihood of non-centrosymmetric crystal packing, as well as enhancing the electronic properties of the molecule (Fichou et al., 1988 ). As part of our ongoing studies in this area (Harrison et al., 2005 ; Harrison, Yathirajan, Sarojini, Narayana & Vijaya Raj, 2006 ), we have prepared the title chalcone derivative, (I) (Fig. 1).

The geometric parameters for (I) are normal. The dihedral angle between the C1–C6 and C10–C15 benzene rings is 7.15 (10)°. The C16 methyl C atom is displaced from the C10–C15 ring plane by 0.059 (4) Å. The enone group is close to planar (r.m.s. deviation from the mean plane of C6–C10 + O1 = 0.028 Å). Overall, the molecule of (I) is approximately planar, which is different from the significantly more twisted conformation of the 4-chloro derivative (Harrison, Yathirajan, Sarojini, Narayana & Indira, 2006 ), where the dihedral angle between the benzene rings is 21.82 (6)°.

The only possible non-van der Waals intermolecular interactions in (I) are C—H⋯O and C—H⋯F bonds arising from the methyl group (Table 2, Fig. 2). There are no π–π stacking interactions in (I).

Compound (I) complements other chalcone derivatives with different substituents X at the 4-fluoro position (see scheme), including X = Cl (Harrison, Yathirajan, Sarojini, Narayana & Indira, 2006), X = OH (Sathiya Moorthi et al., 2005 ), X = CH₃ (Wang et al., 2005 ), X = H (Rabinovich & Schmidt, 1970 ), X = OCH₃ (Zheng et al., 1992 ) and X = NO₂ (Patil et al., 2006 ). All of these compounds crystallize with different structures.

Figure 1
A view of (I)

. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.

Figure 2
The packing in (I)

, viewed down [100], with C—H⋯O and C—H⋯F interactions indicated by dashed lines.

Experimental

4-Fluoroacetophenone (1.38 g, 0.01 mol) in ethanol (25 ml) was mixed with 4-methoxy-benzaldehyde (1.36 g, 0.01 mol) in ethanol (25 ml) and the mixture was treated with an aqueous solution (20 ml) of potassium hydroxide (20 ml, 5%). The resulting mixture was stirred well and left for 24 h, and the solid product was collected by filtration and dried. Crystals of (I) were recrystallized from ethanol (yield 90%; m.p. 371 K). Analysis, found (calculated) for C₁₆H₁₃FO₂: C 74.29 (74.92%), H 5.72 (5.07%).

Crystal data

C₁₆H₁₃FO₂
M_r = 256.26
Orthorhombic, P 2₁ 2₁ 2₁
a = 3.9148 (2) Å
b = 10.1977 (5) Å
c = 30.8052 (14) Å
V = 1229.80 (10) Å³
Z = 4
D_x = 1.384 Mg m⁻³
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 120 (2) K
Block, colourless
0.65 × 0.20 × 0.15 mm

Data collection

Nonius KappaCCD area-detector diffractometer
ω and φ scans
Absorption correction: multi-scan SADABS (Bruker, 2003 ) T_min = 0.938, T_max = 0.985
8063 measured reflections
1669 independent reflections
1402 reflections with I > 2σ(I)
R_int = 0.034
θ_max = 27.5°

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.083
S = 1.09
1669 reflections
174 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0274P)² + 0.45P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max < 0.001
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.17 e Å⁻³
Extinction correction: SHELXL97 (Sheldrick, 1997 )
Extinction coefficient: 0.017 (3)

Table 1
Selected torsion angles (°)

C5—C6—C7—O1	−9.4 (3)
O1—C7—C8—C9	−5.8 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C16—H16B⋯O1ⁱ	0.98	2.56	3.502 (3)	161
C16—H16A⋯F1ⁱⁱ	0.98	2.59	3.458 (3)	148
Symmetry codes: (i) $[-x, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) $[-x+{\script{3\over 2}}, -y+1, z+{\script{1\over 2}}]$ .

In the absence of significant anomalous scattering effects, Friedel pairs were averaged and the absolute structure of the crystal studied is indeterminate. The H atoms were placed in idealized locations (C—H = 0.95–0.98 Å) and refined as riding, with U_iso(H) = 1.2U_eq(C) or 1.5U_eq(methyl C). The methyl group was rotated to fit the electron density.

Data collection: COLLECT (Nonius, 1998 ); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: SCALEPACK, DENZO (Otwinowski & Minor, 1997), and SORTAV (Blessing, 1995 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053680602530X/sg2042sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680602530X/sg2042Isup2.hkl

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK, DENZO (Otwinowski & Minor, 1997), and SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

1-(4-Fluorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one top

Crystal data top

C₁₆H₁₃FO₂	F(000) = 536
M_r = 256.26	D_x = 1.384 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 1541 reflections
a = 3.9148 (2) Å	θ = 1.0–27.5°
b = 10.1977 (5) Å	µ = 0.10 mm⁻¹
c = 30.8052 (14) Å	T = 120 K
V = 1229.80 (10) Å³	Block, colourless
Z = 4	0.65 × 0.20 × 0.15 mm

Data collection top

Nonius KappaCCD area-detector diffractometer	1669 independent reflections
Radiation source: fine-focus sealed tube	1402 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.034
ω and φ scans	θ_max = 27.5°, θ_min = 1.3°
Absorption correction: multi-scan SADABS (Bruker, 2003)	h = −5→4
T_min = 0.938, T_max = 0.985	k = −13→13
8063 measured reflections	l = −40→40

Refinement top

Refinement on F²	Secondary atom site location: none
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.036	H-atom parameters constrained
wR(F²) = 0.083	w = 1/[σ²(F_o²) + (0.0274P)² + 0.45P] where P = (F_o² + 2F_c²)/3
S = 1.09	(Δ/σ)_max < 0.001
1669 reflections	Δρ_max = 0.21 e Å⁻³
174 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.017 (3)

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.3302 (6)	0.5221 (2)	0.08621 (6)	0.0249 (5)
H1	0.3789	0.5496	0.1150	0.030*
C2	0.4042 (7)	0.6047 (2)	0.05194 (6)	0.0271 (5)
H2	0.5029	0.6886	0.0568	0.033*
C3	0.3309 (6)	0.5622 (2)	0.01070 (6)	0.0259 (5)
C4	0.1873 (7)	0.4417 (2)	0.00202 (6)	0.0285 (6)
H4	0.1399	0.4153	−0.0269	0.034*
C5	0.1141 (7)	0.3604 (2)	0.03656 (6)	0.0265 (5)
H5	0.0140	0.2770	0.0313	0.032*
C6	0.1850 (6)	0.39877 (19)	0.07920 (6)	0.0216 (5)
C7	0.0968 (6)	0.3057 (2)	0.11487 (6)	0.0257 (5)
C8	0.2157 (6)	0.3353 (2)	0.15937 (6)	0.0265 (5)
H8	0.3639	0.4078	0.1639	0.032*
C9	0.1196 (6)	0.2625 (2)	0.19346 (6)	0.0249 (5)
H9	−0.0287	0.1909	0.1876	0.030*
C10	0.2193 (6)	0.2817 (2)	0.23866 (6)	0.0227 (5)
C11	0.1246 (6)	0.1895 (2)	0.26996 (6)	0.0242 (5)
H11	−0.0011	0.1142	0.2613	0.029*
C12	0.2094 (6)	0.2053 (2)	0.31321 (6)	0.0241 (5)
H12	0.1451	0.1406	0.3338	0.029*
C13	0.3895 (6)	0.3162 (2)	0.32649 (6)	0.0232 (5)
C14	0.4832 (6)	0.4105 (2)	0.29607 (6)	0.0236 (5)
H14	0.6024	0.4871	0.3049	0.028*
C15	0.4010 (6)	0.39162 (19)	0.25281 (6)	0.0245 (5)
H15	0.4704	0.4553	0.2321	0.029*
C16	0.6316 (7)	0.4400 (2)	0.38472 (7)	0.0323 (6)
H16A	0.6783	0.4321	0.4159	0.048*
H16B	0.4846	0.5162	0.3796	0.048*
H16C	0.8472	0.4512	0.3690	0.048*
O1	−0.0729 (5)	0.20711 (14)	0.10708 (5)	0.0344 (4)
O2	0.4625 (4)	0.32341 (14)	0.36970 (4)	0.0303 (4)
F1	0.4078 (4)	0.64183 (12)	−0.02341 (4)	0.0381 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0287 (14)	0.0251 (10)	0.0210 (9)	0.0020 (10)	−0.0018 (10)	−0.0029 (8)
C2	0.0290 (13)	0.0227 (10)	0.0296 (10)	−0.0013 (11)	0.0023 (10)	−0.0004 (8)
C3	0.0282 (14)	0.0268 (11)	0.0228 (9)	0.0060 (11)	0.0036 (10)	0.0061 (8)
C4	0.0358 (15)	0.0296 (12)	0.0200 (9)	0.0064 (12)	−0.0017 (10)	−0.0030 (8)
C5	0.0310 (13)	0.0214 (10)	0.0271 (10)	−0.0002 (11)	−0.0030 (11)	−0.0023 (8)
C6	0.0201 (12)	0.0226 (10)	0.0222 (9)	0.0022 (9)	0.0000 (9)	−0.0001 (8)
C7	0.0250 (12)	0.0248 (10)	0.0273 (10)	0.0021 (11)	0.0012 (10)	−0.0008 (8)
C8	0.0278 (13)	0.0266 (11)	0.0252 (10)	−0.0022 (11)	−0.0012 (10)	0.0012 (9)
C9	0.0230 (12)	0.0233 (10)	0.0285 (10)	0.0017 (11)	0.0004 (10)	0.0002 (8)
C10	0.0227 (12)	0.0214 (10)	0.0241 (9)	0.0049 (10)	0.0032 (9)	0.0026 (8)
C11	0.0232 (12)	0.0206 (10)	0.0289 (10)	0.0020 (11)	0.0031 (10)	0.0014 (8)
C12	0.0224 (12)	0.0232 (10)	0.0267 (10)	0.0033 (10)	0.0033 (9)	0.0077 (9)
C13	0.0189 (12)	0.0267 (10)	0.0240 (9)	0.0063 (11)	0.0005 (9)	0.0016 (8)
C14	0.0211 (12)	0.0210 (10)	0.0285 (10)	0.0013 (10)	0.0010 (10)	0.0012 (8)
C15	0.0243 (13)	0.0211 (10)	0.0282 (10)	0.0034 (10)	0.0054 (11)	0.0044 (8)
C16	0.0328 (14)	0.0349 (12)	0.0291 (10)	0.0033 (13)	−0.0056 (11)	−0.0064 (9)
O1	0.0414 (10)	0.0291 (8)	0.0327 (8)	−0.0111 (9)	−0.0038 (8)	0.0015 (6)
O2	0.0356 (10)	0.0309 (8)	0.0245 (7)	0.0013 (8)	−0.0037 (7)	0.0016 (6)
F1	0.0527 (10)	0.0345 (7)	0.0270 (6)	0.0042 (8)	0.0086 (7)	0.0092 (5)

Geometric parameters (Å, º) top

C1—C2	1.382 (3)	C9—H9	0.9500
C1—C6	1.397 (3)	C10—C11	1.397 (3)
C1—H1	0.9500	C10—C15	1.397 (3)
C2—C3	1.373 (3)	C11—C12	1.382 (3)
C2—H2	0.9500	C11—H11	0.9500
C3—F1	1.362 (2)	C12—C13	1.394 (3)
C3—C4	1.377 (3)	C12—H12	0.9500
C4—C5	1.379 (3)	C13—O2	1.363 (2)
C4—H4	0.9500	C13—C14	1.392 (3)
C5—C6	1.398 (3)	C14—C15	1.384 (3)
C5—H5	0.9500	C14—H14	0.9500
C6—C7	1.493 (3)	C15—H15	0.9500
C7—O1	1.229 (3)	C16—O2	1.437 (3)
C7—C8	1.479 (3)	C16—H16A	0.9800
C8—C9	1.340 (3)	C16—H16B	0.9800
C8—H8	0.9500	C16—H16C	0.9800
C9—C10	1.460 (3)

C2—C1—C6	121.08 (19)	C10—C9—H9	116.6
C2—C1—H1	119.5	C11—C10—C15	117.37 (18)
C6—C1—H1	119.5	C11—C10—C9	119.79 (19)
C3—C2—C1	118.06 (19)	C15—C10—C9	122.81 (18)
C3—C2—H2	121.0	C12—C11—C10	121.5 (2)
C1—C2—H2	121.0	C12—C11—H11	119.2
F1—C3—C2	118.63 (19)	C10—C11—H11	119.2
F1—C3—C4	118.20 (18)	C11—C12—C13	119.91 (19)
C2—C3—C4	123.16 (19)	C11—C12—H12	120.0
C3—C4—C5	118.11 (18)	C13—C12—H12	120.0
C3—C4—H4	120.9	O2—C13—C14	124.38 (19)
C5—C4—H4	120.9	O2—C13—C12	115.88 (18)
C4—C5—C6	121.03 (19)	C14—C13—C12	119.74 (18)
C4—C5—H5	119.5	C15—C14—C13	119.4 (2)
C6—C5—H5	119.5	C15—C14—H14	120.3
C1—C6—C5	118.56 (18)	C13—C14—H14	120.3
C1—C6—C7	123.56 (18)	C14—C15—C10	122.01 (19)
C5—C6—C7	117.88 (18)	C14—C15—H15	119.0
O1—C7—C8	121.24 (19)	C10—C15—H15	119.0
O1—C7—C6	120.10 (18)	O2—C16—H16A	109.5
C8—C7—C6	118.66 (19)	O2—C16—H16B	109.5
C9—C8—C7	121.6 (2)	H16A—C16—H16B	109.5
C9—C8—H8	119.2	O2—C16—H16C	109.5
C7—C8—H8	119.2	H16A—C16—H16C	109.5
C8—C9—C10	126.7 (2)	H16B—C16—H16C	109.5
C8—C9—H9	116.6	C13—O2—C16	117.11 (16)

C6—C1—C2—C3	0.0 (4)	C7—C8—C9—C10	180.0 (2)
C1—C2—C3—F1	−178.9 (2)	C8—C9—C10—C11	−173.7 (2)
C1—C2—C3—C4	0.2 (4)	C8—C9—C10—C15	8.0 (4)
F1—C3—C4—C5	179.1 (2)	C15—C10—C11—C12	−0.6 (3)
C2—C3—C4—C5	0.0 (4)	C9—C10—C11—C12	−179.0 (2)
C3—C4—C5—C6	−0.3 (4)	C10—C11—C12—C13	0.9 (3)
C2—C1—C6—C5	−0.2 (3)	C11—C12—C13—O2	−179.9 (2)
C2—C1—C6—C7	−179.5 (2)	C11—C12—C13—C14	−0.1 (3)
C4—C5—C6—C1	0.4 (3)	O2—C13—C14—C15	178.7 (2)
C4—C5—C6—C7	179.7 (2)	C12—C13—C14—C15	−1.1 (3)
C1—C6—C7—O1	169.8 (2)	C13—C14—C15—C10	1.5 (3)
C5—C6—C7—O1	−9.4 (3)	C11—C10—C15—C14	−0.6 (3)
C1—C6—C7—C8	−9.8 (3)	C9—C10—C15—C14	177.7 (2)
C5—C6—C7—C8	171.0 (2)	C14—C13—O2—C16	3.5 (3)
O1—C7—C8—C9	−5.8 (4)	C12—C13—O2—C16	−176.71 (19)
C6—C7—C8—C9	173.8 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16B···O1ⁱ	0.98	2.56	3.502 (3)	161
C16—H16A···F1ⁱⁱ	0.98	2.59	3.458 (3)	148

Symmetry codes: (i) −x, y+1/2, −z+1/2; (ii) −x+3/2, −y+1, z+1/2.

Acknowledgements

The authors thank the EPSRC National Crystallography Service (University of Southampton) for data collection. HGS thanks the University of Mysore for provision of research facilities. BKS thanks AICTE, Government of India, New Delhi, for financial assistance under the Career Award for Young Teachers (CAYT) scheme.

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