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

Harrison, W.T.A.; Yathirajan, H.S.; Sarojini, B.K.; Narayana, B.; Indira, J.

doi:10.1107/S1600536806010865

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 62| Part 4| April 2006| Pages o1647-o1649

https://doi.org/10.1107/S1600536806010865

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

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

^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, ^dDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, India, and ^eDepartment of Physics, University College, Mangalore 575 001, India
^*Correspondence e-mail: w.harrison@abdn.ac.uk

(Received 23 March 2006; accepted 24 March 2006; online 31 March 2006)

The geometrical parameters for the title compound, C₁₆H₁₃ClO₂, are normal. Packing in a non-centrosymmetric space group, which is consistent with the non-zero second harmonic generation response, may be influenced by a C—H⋯O interaction.

Comment

The title compound, (I) (Fig. 1), was prepared as part of our ongoing studies (Indira et al., 2002 ; Harrison et al., 2005 , 2006 ) of the non-linear optical (NLO) properties of chalcone derivatives (Uchida et al., 1998 ). The non-centrosymmetric, polar crystal structure of (I) is consistent with its significant second harmonic generation (SHG) response of 0.8 times that of urea (Watson et al., 1993 ).

The geometrical parameters for (I) are normal (Allen et al., 1987 ) and consistent with those of other recently reported chalcone derivatives (Rosli et al., 2006 ; Patil et al., 2006 ). Compound (I) complements several closely related molecules with other 4-substituents X instead of Cl (see scheme), namely (II) with X = OH (Moorthi et al., 2005 ), (III) with X = CH₃ (Wang et al., 2005 ), (IV) with X = H (Rabinovich & Schmidt, 1970 ), and (V) with X = OCH₃ (Zheng et al., 1992 ). The space groups for (I), (II), (III), (IV) and (V) are Pna2₁, Pbca, P2₁/c, P2₁ and P2₁2₁2₁, respectively. The distribution of space groups for this small family is thus consistent with the observation that chalcones are prone to crystallize as non-centrosymmetric structures (Uchida et al., 1998).

The molecule of (I) is distinctly twisted about the C6—C7 and the C7—C8 bonds (Table 1), as was also seen for 2-bromo-1-chlorophenyl-3-(4-methoxyphenyl)-2-propen-1-one (Harrison et al., 2006). The dihedral angle between the benzene ring mean planes (C1–C6 and C10–C15) in (I) is 21.82 (6)°. Cl1, C7 and O1 deviate from the former mean plane by 0.031 (3), 0.022 (3) and 0.346 (3) Å, respectively. The deviations of C9, O2 and C16 from the latter plane are 0.087 (3), 0.038 (3) and 0.049 (3) Å, respectively.

A PLATON (Spek, 2003 ) analysis of (I) indicated a possible intramolecular C9—H9⋯O1 interaction (Table 2) that might help to maintain the molecular conformation. A similar interaction was proposed for 3-(4-bromophenyl)-1-(4-nitrophenyl)-prop-2-en-1-one (Rosli et al., 2006).

An intermolecular C—H⋯O hydrogen bond (Fig. 2) appears to help to assemble the molecules of (I) into helical stacks about the 2₁ screw axis, propagating in the polar [001] direction.

Figure 1
View of (I)

, showing 50% displacement ellipsoids (arbitrary spheres for the H atoms). The possible intramolecular C—H⋯O interaction is indicated by a dashed line.

Figure 2
The packing for (I)

, viewed down [001], with C—H⋯O interactions shown as dashed lines.

Experimental

4-Chloroacetophenone in ethanol (1.54 g, 0.01 mol) (25 ml) was mixed with 4-methoxybenzaldehyde (1.36 g, 0.01 mol) in ethanol (25 ml) and the mixture was treated with an aqueous solution of potassium hydroxide (20 ml, 5%). This mixture was stirred well and left to stand for 24 hr. The resulting crude solid mass was collected by filtration and recrystallized from ethanol, yielding clear blocks of (I). Yield: 90%, m.p.: 380 K, analysis found (calc.) for C₁₆H₁₃ClO₂, C 70.5 (70.4%); H 4.72 (4.76%).

Crystal data

C₁₆H₁₃ClO₂
M_r = 272.71
Orthorhombic, P n a 2₁
a = 12.8179 (4) Å
b = 25.5550 (6) Å
c = 3.9175 (1) Å
V = 1283.22 (6) Å³
Z = 4
D_x = 1.412 Mg m⁻³
Mo Kα radiation
Cell parameters from 1708 reflections
θ = 2.9–27.5°
μ = 0.29 mm⁻¹
T = 120 (2) K
Slab, colourless
0.50 × 0.40 × 0.20 mm

Data collection

Nonius KappaCCD diffractometer
ω and φ scans
Absorption correction: multi-scan (SADABS; Bruker, 2003 ) T_min = 0.868, T_max = 0.944
8514 measured reflections
2815 independent reflections
2569 reflections with I > 2σ(I)
R_int = 0.028
θ_max = 27.5°
h = −9 → 16
k = −33 → 32
l = −5 → 5

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.071
S = 1.04
2815 reflections
173 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0355P)² + 0.2552P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.22 e Å⁻³
Absolute structure: Flack (1983 ), 1131 Friedel pairs
Flack parameter: 0.02 (6)

Table 1
Selected geometric parameters (Å, °)

C6—C7	1.496 (2)
C7—C8	1.479 (2)
C8—C9	1.342 (2)
C9—C10	1.461 (2)

C5—C6—C7—O1	16.7 (2)
O1—C7—C8—C9	6.4 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9⋯O1	0.95	2.46	2.8065 (19)	102
C12—H12⋯O1ⁱ	0.95	2.54	3.4828 (18)	175
Symmetry code: (i) $[-x+1, -y, z-{\script{1\over 2}}]$ .

H atoms were positioned geometrically (C—H = 0.95–0.98 Å) and refined as riding, with U_iso(H) = 1.2U_eq(carrier) or 1.5U_eq(methyl carrier). The methyl group was rotated to fit the electron density.

Data collection: COLLECT (Nonius, 1998 ); cell refinement: HKL SCALEPACK (Otwinowski & Minor 1997 ); data reduction: HKL DENZO (Otwinowski & Minor 1997), SCALEPACK 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/S1600536806010865/sj2028sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536806010865/sj2028Isup2.hkl

Computing details top

Data collection: Collect (Nonius, 1998); cell refinement: HKL SCALEPACK (Otwinowski & Minor 1997); data reduction: HKL DENZO (Otwinowski & Minor 1997), SCALEPACK 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-Chlorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one top

Crystal data top

C₁₆H₁₃ClO₂	F(000) = 568
M_r = 272.71	D_x = 1.412 Mg m⁻³
Orthorhombic, Pna2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2n	Cell parameters from 1708 reflections
a = 12.8179 (4) Å	θ = 2.9–27.5°
b = 25.5550 (6) Å	µ = 0.29 mm⁻¹
c = 3.9175 (1) Å	T = 120 K
V = 1283.22 (6) Å³	Slab, colourless
Z = 4	0.50 × 0.40 × 0.20 mm

Data collection top

Nonius KappaCCD diffractometer	2815 independent reflections
Radiation source: fine-focus sealed tube	2569 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
ω and φ scans	θ_max = 27.5°, θ_min = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2003)	h = −9→16
T_min = 0.868, T_max = 0.944	k = −33→32
8514 measured reflections	l = −5→5

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)] = 0.029	H-atom parameters constrained
wR(F²) = 0.071	w = 1/[σ²(F_o²) + (0.0355P)² + 0.2552P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
2815 reflections	Δρ_max = 0.23 e Å⁻³
173 parameters	Δρ_min = −0.22 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1131 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.02 (6)

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	0.19574 (12)	0.20035 (6)	0.2960 (4)	0.0205 (4)
H1	0.2650	0.2112	0.2462	0.025*
C2	0.12683 (13)	0.23537 (5)	0.4453 (5)	0.0218 (3)
H2	0.1483	0.2700	0.4976	0.026*
C3	0.02617 (12)	0.21890 (6)	0.5169 (4)	0.0200 (3)
C4	−0.00692 (12)	0.16853 (6)	0.4450 (5)	0.0236 (3)
H4	−0.0760	0.1577	0.4979	0.028*
C5	0.06269 (12)	0.13431 (6)	0.2947 (4)	0.0222 (4)
H5	0.0407	0.0997	0.2424	0.027*
C6	0.16443 (10)	0.14935 (5)	0.2180 (5)	0.0173 (3)
C7	0.23496 (12)	0.11027 (6)	0.0517 (4)	0.0190 (3)
C8	0.34886 (12)	0.11936 (6)	0.0601 (4)	0.0191 (3)
H8	0.3764	0.1480	0.1861	0.023*
C9	0.41349 (11)	0.08728 (6)	−0.1098 (4)	0.0185 (3)
H9	0.3813	0.0609	−0.2440	0.022*
C10	0.52748 (12)	0.08815 (5)	−0.1131 (4)	0.0175 (3)
C11	0.57984 (11)	0.04602 (5)	−0.2616 (4)	0.0184 (3)
H11	0.5401	0.0193	−0.3690	0.022*
C12	0.68784 (11)	0.04173 (5)	−0.2580 (5)	0.0195 (3)
H12	0.7215	0.0123	−0.3569	0.023*
C13	0.74565 (12)	0.08153 (6)	−0.1062 (4)	0.0190 (3)
C14	0.69544 (12)	0.12507 (6)	0.0340 (5)	0.0210 (3)
H14	0.7355	0.1527	0.1299	0.025*
C15	0.58780 (12)	0.12813 (6)	0.0338 (4)	0.0197 (3)
H15	0.5543	0.1575	0.1339	0.024*
C16	0.90530 (12)	0.03755 (6)	−0.2288 (5)	0.0257 (4)
H16A	0.9806	0.0415	−0.1942	0.039*
H16B	0.8903	0.0357	−0.4738	0.039*
H16C	0.8814	0.0054	−0.1177	0.039*
O1	0.19706 (8)	0.07117 (4)	−0.0837 (4)	0.0237 (3)
O2	0.85193 (8)	0.08157 (4)	−0.0835 (3)	0.0234 (3)
Cl1	−0.06159 (3)	0.262892 (14)	0.69857 (14)	0.02734 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0165 (7)	0.0197 (7)	0.0252 (10)	0.0001 (6)	−0.0015 (6)	0.0032 (6)
C2	0.0235 (8)	0.0168 (6)	0.0252 (9)	0.0001 (6)	−0.0030 (7)	−0.0002 (6)
C3	0.0198 (7)	0.0225 (7)	0.0179 (8)	0.0074 (6)	−0.0012 (7)	0.0017 (6)
C4	0.0178 (7)	0.0275 (7)	0.0256 (9)	−0.0026 (6)	−0.0001 (7)	0.0017 (7)
C5	0.0202 (7)	0.0205 (7)	0.0257 (10)	−0.0025 (6)	−0.0007 (7)	−0.0004 (6)
C6	0.0168 (6)	0.0186 (6)	0.0167 (7)	0.0017 (5)	−0.0036 (7)	0.0015 (7)
C7	0.0206 (8)	0.0188 (7)	0.0176 (8)	0.0009 (6)	−0.0022 (6)	0.0047 (6)
C8	0.0179 (7)	0.0189 (7)	0.0204 (8)	0.0006 (6)	−0.0018 (6)	0.0017 (6)
C9	0.0211 (8)	0.0182 (6)	0.0161 (8)	−0.0015 (6)	−0.0007 (7)	0.0018 (6)
C10	0.0182 (7)	0.0186 (6)	0.0157 (8)	0.0011 (6)	0.0008 (6)	0.0016 (7)
C11	0.0223 (7)	0.0171 (6)	0.0159 (8)	−0.0025 (5)	−0.0003 (7)	−0.0013 (6)
C12	0.0215 (7)	0.0174 (6)	0.0198 (9)	0.0024 (5)	0.0037 (7)	−0.0005 (6)
C13	0.0178 (7)	0.0204 (7)	0.0189 (8)	−0.0010 (6)	0.0007 (7)	0.0030 (6)
C14	0.0219 (8)	0.0176 (6)	0.0234 (9)	−0.0018 (6)	−0.0018 (7)	−0.0016 (6)
C15	0.0228 (8)	0.0163 (7)	0.0201 (8)	0.0027 (6)	0.0012 (7)	−0.0012 (6)
C16	0.0195 (7)	0.0276 (7)	0.0300 (11)	0.0052 (6)	0.0002 (7)	−0.0050 (7)
O1	0.0211 (6)	0.0198 (5)	0.0301 (6)	−0.0011 (4)	−0.0028 (5)	−0.0037 (5)
O2	0.0150 (5)	0.0235 (5)	0.0318 (7)	0.0017 (4)	−0.0007 (5)	−0.0046 (5)
Cl1	0.02487 (18)	0.03005 (18)	0.0271 (2)	0.00920 (15)	0.0001 (2)	−0.00342 (19)

Geometric parameters (Å, º) top

C1—C2	1.387 (2)	C9—H9	0.9500
C1—C6	1.3976 (19)	C10—C11	1.396 (2)
C1—H1	0.9500	C10—C15	1.405 (2)
C2—C3	1.386 (2)	C11—C12	1.3888 (19)
C2—H2	0.9500	C11—H11	0.9500
C3—C4	1.384 (2)	C12—C13	1.392 (2)
C3—Cl1	1.7423 (16)	C12—H12	0.9500
C4—C5	1.381 (2)	C13—O2	1.3653 (18)
C4—H4	0.9500	C13—C14	1.398 (2)
C5—C6	1.392 (2)	C14—C15	1.382 (2)
C5—H5	0.9500	C14—H14	0.9500
C6—C7	1.496 (2)	C15—H15	0.9500
C7—O1	1.2312 (19)	C16—O2	1.4344 (19)
C7—C8	1.479 (2)	C16—H16A	0.9800
C8—C9	1.342 (2)	C16—H16B	0.9800
C8—H8	0.9500	C16—H16C	0.9800
C9—C10	1.461 (2)

C2—C1—C6	120.75 (14)	C10—C9—H9	116.1
C2—C1—H1	119.6	C11—C10—C15	117.85 (13)
C6—C1—H1	119.6	C11—C10—C9	118.20 (13)
C3—C2—C1	118.84 (14)	C15—C10—C9	123.91 (14)
C3—C2—H2	120.6	C12—C11—C10	122.40 (14)
C1—C2—H2	120.6	C12—C11—H11	118.8
C4—C3—C2	121.77 (15)	C10—C11—H11	118.8
C4—C3—Cl1	119.04 (12)	C11—C12—C13	118.51 (14)
C2—C3—Cl1	119.19 (12)	C11—C12—H12	120.7
C5—C4—C3	118.53 (15)	C13—C12—H12	120.7
C5—C4—H4	120.7	O2—C13—C12	124.03 (13)
C3—C4—H4	120.7	O2—C13—C14	115.67 (13)
C4—C5—C6	121.49 (14)	C12—C13—C14	120.30 (14)
C4—C5—H5	119.3	C15—C14—C13	120.29 (14)
C6—C5—H5	119.3	C15—C14—H14	119.9
C5—C6—C1	118.63 (14)	C13—C14—H14	119.9
C5—C6—C7	118.40 (13)	C14—C15—C10	120.58 (14)
C1—C6—C7	122.97 (13)	C14—C15—H15	119.7
O1—C7—C8	121.77 (14)	C10—C15—H15	119.7
O1—C7—C6	119.40 (14)	O2—C16—H16A	109.5
C8—C7—C6	118.82 (13)	O2—C16—H16B	109.5
C9—C8—C7	120.17 (14)	H16A—C16—H16B	109.5
C9—C8—H8	119.9	O2—C16—H16C	109.5
C7—C8—H8	119.9	H16A—C16—H16C	109.5
C8—C9—C10	127.75 (14)	H16B—C16—H16C	109.5
C8—C9—H9	116.1	C13—O2—C16	116.71 (12)

C6—C1—C2—C3	0.2 (2)	C7—C8—C9—C10	−175.77 (14)
C1—C2—C3—C4	0.3 (3)	C8—C9—C10—C11	169.56 (16)
C1—C2—C3—Cl1	−179.03 (13)	C8—C9—C10—C15	−8.4 (3)
C2—C3—C4—C5	−0.7 (3)	C15—C10—C11—C12	2.2 (3)
Cl1—C3—C4—C5	178.70 (13)	C9—C10—C11—C12	−175.87 (15)
C3—C4—C5—C6	0.5 (3)	C10—C11—C12—C13	−1.3 (3)
C4—C5—C6—C1	−0.1 (3)	C11—C12—C13—O2	179.30 (15)
C4—C5—C6—C7	−179.34 (15)	C11—C12—C13—C14	−1.0 (3)
C2—C1—C6—C5	−0.3 (2)	O2—C13—C14—C15	−178.00 (15)
C2—C1—C6—C7	178.96 (16)	C12—C13—C14—C15	2.3 (3)
C5—C6—C7—O1	16.7 (2)	C13—C14—C15—C10	−1.3 (3)
C1—C6—C7—O1	−162.55 (15)	C11—C10—C15—C14	−0.9 (3)
C5—C6—C7—C8	−162.25 (15)	C9—C10—C15—C14	177.08 (15)
C1—C6—C7—C8	18.5 (2)	C12—C13—O2—C16	0.4 (2)
O1—C7—C8—C9	6.4 (2)	C14—C13—O2—C16	−179.36 (14)
C6—C7—C8—C9	−174.69 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9···O1	0.95	2.46	2.8065 (19)	102
C12—H12···O1ⁱ	0.95	2.54	3.4828 (18)	175

Symmetry code: (i) −x+1, −y, z−1/2.

Acknowledgements

We thank the EPSRC National Crystallography Service (University of Southampton) for the data collection. BKS thanks AICTE, Government of India, New Delhi for financial assistance under the `Career Award for Young Teachers' scheme.

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