2-Bromo-1,3-bis­(4-chloro­phen­yl)prop-2-en-1-one

Harrison, W.T.A.; Hakim Al-Arique, Q.N.M.; Narayana, B.; Yathirajan, H.S.; Sarojini, B.K.

doi:10.1107/S160053680903815X

organic compounds

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ISSN: 2056-9890

Volume 65| Part 11| November 2009| Page o2648

https://doi.org/10.1107/S160053680903815X

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2-Bromo-1,3-bis(4-chlorophenyl)prop-2-en-1-one

William T. A. Harrison,^a ^* Q. N. M. Hakim Al-Arique,^b B. Narayana,^c H. S. Yathirajan ^b and B. K. Sarojini ^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, Mangalore University, Mangalagangotri 574 199, India, and ^dDepartment of Chemistry, P. A. College of Engineering, Nadupadavu, Mangalore 574 153, India
^*Correspondence e-mail: w.harrison@abdn.ac.uk

(Received 15 June 2009; accepted 21 September 2009; online 3 October 2009)

In the title compound, C₁₅H₉BrCl₂O, the two benzene rings are twisted from each other with a dihedral angle of 47.33 (8)°. The crystal structure is stabilized by aromatic π–π interactions between the benzene rings of neighbouring molecules [centroid–centroid distance = 3.680 (2) Å], and by weak intermolecular C—H⋯O and C—H⋯Cl interactions. Additionally, the crystal structure exhibits a short intramolecular C—H⋯Br contact (H⋯Br = 2.69 Å).

Related literature

For background on chalcones as possible nonlinear optical materials, see: Harrison et al. (2006 ). For related structures with the same backbone and different substituents on the aromatic rings, see: Butcher et al. (2006 , 2007 ); Dhanasekaran et al. (2007a ,b ); Fun et al. (2008 ).

Experimental

Crystal data

C₁₅H₉BrCl₂O
M_r = 356.03
Monoclinic, P 2₁
a = 7.7416 (3) Å
b = 9.7981 (4) Å
c = 9.6717 (3) Å
β = 109.075 (2)°
V = 693.34 (5) Å³
Z = 2
Mo Kα radiation
μ = 3.34 mm⁻¹
T = 120 K
0.18 × 0.16 × 0.06 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2003 ) T_min = 0.585, T_max = 0.824
12526 measured reflections
3129 independent reflections
2873 reflections with I > 2σ(I)
R_int = 0.040

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.079
S = 1.04
3129 reflections
172 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 1.20 e Å⁻³
Δρ_min = −0.46 e Å⁻³
Absolute structure: Flack (1983 ), 1434 Friedel pairs
Flack parameter: 0.044 (9)

Table 1
Selected torsion angles (°)

C6—C7—C8—C9	32.6 (5)
O1—C7—C8—Br1	31.2 (5)
C7—C8—C9—C10	174.4 (4)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1⋯O1ⁱ	0.95	2.47	3.411 (5)	171
C11—H11⋯Cl1ⁱⁱ	0.95	2.81	3.619 (4)	143
C15—H15⋯Br1	0.95	2.69	3.377 (4)	129
Symmetry codes: (i) $[-x+1, y-{\script{1\over 2}}, -z+1]$ ; (ii) $[-x+1, y-{\script{1\over 2}}, -z+2]$ .

Data collection: COLLECT (Nonius, 1998 ); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ); data reduction: DENZO (Otwinowski & Minor, 1997), SCALEPACK and SORTAV (Blessing, 1995 ); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); 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/S160053680903815X/lx2111sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680903815X/lx2111Isup2.hkl

checkCIF report

Comment top

As part of our ongoing investigations of chalcone derivatives as possible non-linear optical materials (Harrison et al., 2006), we now report the synthesis and structure of the noncentrosymmetric title compound, (I), (Fig 1.).

The molecule adopts a twisted conformation with the dihedral angle between ring A (C1-C6) and ring B (C10-C15) being 47.33 (8)°. Some of the atoms bonded to the benzene rings deviate significantly from their attached ring planes: Cl1 and C7 deviate by 0.106 (5) and 0.140 (6)Å respectively from the mean plane of C1-C6 and Cl2 and C9 deviate by 0.028 (5) and 0.063 (6)Å from the mean plane of C10-C15. The dihedral angles between atoms C7/C8/C9 and ring planes A and B are 55.9 (2) and 20.1 (3)°, respectively. The strongly twisted conformation (Table 1) may arise, in part, to relieve the short intramolecular H1···H9 contact of 2.35 Å. A short intramolecular C–H···Br contact occurs (Table 1).

The crystal packing for (I) is influenced by weak intermolecular C–H···O and C–H···Cl interactions (Table 2), resulting in a noncentrosymmetric structure. The C–H···O links lead to chains propagating in [010], which appear to be reinforced by aromatic π–π stacking between the A and B rings [centroid-centroid separation = 3.680 (2) Å; inter-plane angle = 10.82 (19)°]. The weaker C–H···Cl interaction also generates [010] chains and together, the non-classical bonds lead to (100) sheets.

Related literature top

For background on chalcones as possible nonlinear optical materials, see: Harrison et al. (2006). For related structures with the same backbone and different substituents on the aromatic rings, see: Butcher et al. (2006, 2007); Dhanasekaran et al. (2007a,b); Fun et al. (2008).

Experimental top

2,3-Dibromo-1,3-[bis(4-chlorophenyl)]-2-propan-1-one (4.32 g, 0.01 mol) was mixed with triethylamine (5 ml, 0.05 mol) in toluene (100 ml). The mixture was stirred well for 24 hrs and the precipitated ethylenehydrobromide was filtered off and the solvent was removed under reduced pressure. The resulting solid mass obtained on cooling was collected by filtration. The compound was dried and recrystallized four times with ethanol to yield colourless blocks of (I). Yield: 60%; m. p.: 325-328 K; analysis for C₁₅H₉BrCl₂O: found (calculated): C: 18.01 (18.02); H: 9.15 (9.07).

Structure description top

For background on chalcones as possible nonlinear optical materials, see: Harrison et al. (2006). For related structures with the same backbone and different substituents on the aromatic rings, see: Butcher et al. (2006, 2007); Dhanasekaran et al. (2007a,b); Fun et al. (2008).

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997) and SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. View of the molecular structure of (I) showing 50% displacement ellipsoids. The H atoms are drawn as spheres of arbitrary radius.

2-Bromo-1,3-bis(4-chlorophenyl)prop-2-en-1-one top

Crystal data top

C₁₅H₉BrCl₂O	F(000) = 352
M_r = 356.03	D_x = 1.705 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 13953 reflections
a = 7.7416 (3) Å	θ = 2.9–27.5°
b = 9.7981 (4) Å	µ = 3.34 mm⁻¹
c = 9.6717 (3) Å	T = 120 K
β = 109.075 (2)°	Block, colourless
V = 693.34 (5) Å³	0.18 × 0.16 × 0.06 mm
Z = 2

Data collection top

Nonius KappaCCD diffractometer	3129 independent reflections
Radiation source: fine-focus sealed tube	2873 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.040
Detector resolution: 10.0 pixels mm^-1	θ_max = 27.5°, θ_min = 3.1°
ω and φ scans	h = −10→10
Absorption correction: multi-scan (SADABS; Bruker, 2003)	k = −12→12
T_min = 0.585, T_max = 0.824	l = −12→12
12526 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.036	H-atom parameters constrained
wR(F²) = 0.079	w = 1/[σ²(F_o²) + (0.0258P)² + 0.5496P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
3129 reflections	Δρ_max = 1.20 e Å⁻³
172 parameters	Δρ_min = −0.46 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 1434 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.044 (9)

Crystal data top

C₁₅H₉BrCl₂O	V = 693.34 (5) Å³
M_r = 356.03	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 7.7416 (3) Å	µ = 3.34 mm⁻¹
b = 9.7981 (4) Å	T = 120 K
c = 9.6717 (3) Å	0.18 × 0.16 × 0.06 mm
β = 109.075 (2)°

Data collection top

Nonius KappaCCD diffractometer	3129 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2003)	2873 reflections with I > 2σ(I)
T_min = 0.585, T_max = 0.824	R_int = 0.040
12526 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	H-atom parameters constrained
wR(F²) = 0.079	Δρ_max = 1.20 e Å⁻³
S = 1.04	Δρ_min = −0.46 e Å⁻³
3129 reflections	Absolute structure: Flack (1983), 1434 Friedel pairs
172 parameters	Absolute structure parameter: 0.044 (9)
1 restraint

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	0.5669 (5)	0.6271 (3)	0.7407 (4)	0.0255 (8)
H1	0.5761	0.5621	0.6706	0.031*
C2	0.6586 (5)	0.6046 (4)	0.8887 (4)	0.0266 (8)
H2	0.7296	0.5245	0.9206	0.032*
C3	0.6438 (4)	0.7025 (4)	0.9891 (3)	0.0241 (6)
C4	0.5385 (5)	0.8181 (4)	0.9458 (4)	0.0288 (8)
H4	0.5283	0.8825	1.0160	0.035*
C5	0.4479 (5)	0.8387 (4)	0.7982 (4)	0.0292 (8)
H5	0.3753	0.9182	0.7670	0.035*
C6	0.4622 (5)	0.7436 (3)	0.6945 (4)	0.0250 (8)
C7	0.3742 (5)	0.7800 (4)	0.5351 (4)	0.0277 (8)
C8	0.3109 (5)	0.6665 (4)	0.4271 (4)	0.0271 (8)
C9	0.2468 (5)	0.5475 (4)	0.4610 (4)	0.0252 (8)
H9	0.2575	0.5416	0.5615	0.030*
C10	0.1645 (5)	0.4256 (4)	0.3785 (4)	0.0237 (7)
C11	0.1567 (5)	0.3124 (4)	0.4629 (4)	0.0304 (8)
H11	0.2057	0.3188	0.5665	0.037*
C12	0.0786 (5)	0.1897 (4)	0.3994 (4)	0.0341 (9)
H12	0.0774	0.1119	0.4578	0.041*
C13	0.0028 (5)	0.1849 (4)	0.2478 (4)	0.0303 (8)
C14	0.0093 (5)	0.2951 (4)	0.1604 (4)	0.0316 (9)
H14	−0.0427	0.2890	0.0570	0.038*
C15	0.0928 (5)	0.4146 (4)	0.2258 (4)	0.0276 (8)
H15	0.1016	0.4899	0.1665	0.033*
O1	0.3501 (5)	0.8986 (3)	0.4961 (3)	0.0440 (8)
Cl1	0.76953 (13)	0.67976 (9)	1.17307 (9)	0.0352 (2)
Cl2	−0.10057 (15)	0.03386 (11)	0.16691 (12)	0.0460 (3)
Br1	0.31668 (5)	0.71253 (4)	0.23765 (4)	0.03793 (12)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0331 (19)	0.0179 (17)	0.0270 (17)	−0.0089 (15)	0.0120 (15)	−0.0038 (14)
C2	0.0268 (18)	0.0234 (18)	0.0321 (19)	0.0006 (15)	0.0130 (15)	−0.0016 (15)
C3	0.0265 (15)	0.0222 (16)	0.0272 (14)	−0.0041 (17)	0.0138 (12)	−0.0040 (17)
C4	0.0303 (19)	0.0246 (18)	0.037 (2)	−0.0052 (16)	0.0185 (16)	−0.0088 (16)
C5	0.0298 (19)	0.0202 (18)	0.040 (2)	−0.0016 (15)	0.0142 (17)	−0.0070 (16)
C6	0.0219 (16)	0.023 (2)	0.0308 (17)	−0.0049 (13)	0.0095 (13)	0.0000 (14)
C7	0.0249 (18)	0.0258 (19)	0.0325 (19)	−0.0014 (15)	0.0094 (15)	0.0036 (16)
C8	0.0251 (17)	0.031 (2)	0.0248 (17)	−0.0008 (14)	0.0068 (14)	0.0095 (14)
C9	0.0223 (17)	0.0268 (19)	0.0232 (16)	0.0026 (15)	0.0028 (14)	−0.0031 (15)
C10	0.0208 (16)	0.0231 (18)	0.0252 (17)	−0.0012 (14)	0.0049 (14)	−0.0020 (14)
C11	0.038 (2)	0.031 (2)	0.0240 (17)	−0.0122 (17)	0.0122 (16)	−0.0030 (16)
C12	0.041 (2)	0.033 (2)	0.0329 (17)	−0.0120 (19)	0.0179 (16)	−0.0028 (18)
C13	0.0268 (17)	0.034 (2)	0.0318 (16)	−0.0077 (16)	0.0124 (14)	−0.0120 (17)
C14	0.0270 (19)	0.038 (2)	0.0254 (18)	0.0029 (16)	0.0022 (15)	−0.0114 (17)
C15	0.0248 (18)	0.0290 (19)	0.0282 (18)	0.0011 (15)	0.0077 (15)	−0.0005 (16)
O1	0.075 (2)	0.0152 (13)	0.0357 (15)	−0.0042 (14)	0.0097 (15)	0.0106 (12)
Cl1	0.0448 (5)	0.0336 (6)	0.0279 (4)	−0.0016 (4)	0.0131 (4)	−0.0049 (4)
Cl2	0.0468 (6)	0.0417 (6)	0.0522 (6)	−0.0183 (5)	0.0199 (5)	−0.0197 (5)
Br1	0.0425 (2)	0.0432 (2)	0.02831 (17)	−0.0063 (2)	0.01189 (14)	0.01032 (19)

Geometric parameters (Å, º) top

C1—C6	1.387 (5)	C8—Br1	1.902 (3)
C1—C2	1.392 (5)	C9—C10	1.462 (5)
C1—H1	0.9500	C9—H9	0.9500
C2—C3	1.397 (5)	C10—C11	1.391 (5)
C2—H2	0.9500	C10—C15	1.402 (5)
C3—C4	1.378 (5)	C11—C12	1.395 (5)
C3—Cl1	1.741 (3)	C11—H11	0.9500
C4—C5	1.384 (5)	C12—C13	1.391 (5)
C4—H4	0.9500	C12—H12	0.9500
C5—C6	1.399 (5)	C13—C14	1.382 (6)
C5—H5	0.9500	C13—Cl2	1.742 (4)
C6—C7	1.510 (5)	C14—C15	1.387 (6)
C7—O1	1.217 (5)	C14—H14	0.9500
C7—C8	1.495 (5)	C15—H15	0.9500
C8—C9	1.349 (5)

C6—C1—C2	120.6 (3)	C7—C8—Br1	113.0 (2)
C6—C1—H1	119.7	C8—C9—C10	134.7 (3)
C2—C1—H1	119.7	C8—C9—H9	112.7
C1—C2—C3	118.4 (3)	C10—C9—H9	112.7
C1—C2—H2	120.8	C11—C10—C15	118.7 (3)
C3—C2—H2	120.8	C11—C10—C9	115.2 (3)
C4—C3—C2	121.8 (3)	C15—C10—C9	126.1 (3)
C4—C3—Cl1	119.6 (3)	C10—C11—C12	121.6 (3)
C2—C3—Cl1	118.5 (3)	C10—C11—H11	119.2
C3—C4—C5	119.0 (3)	C12—C11—H11	119.2
C3—C4—H4	120.5	C13—C12—C11	117.8 (4)
C5—C4—H4	120.5	C13—C12—H12	121.1
C4—C5—C6	120.6 (3)	C11—C12—H12	121.1
C4—C5—H5	119.7	C14—C13—C12	122.1 (4)
C6—C5—H5	119.7	C14—C13—Cl2	119.5 (3)
C1—C6—C5	119.5 (3)	C12—C13—Cl2	118.4 (3)
C1—C6—C7	123.0 (3)	C13—C14—C15	119.1 (3)
C5—C6—C7	117.3 (3)	C13—C14—H14	120.5
O1—C7—C8	120.8 (3)	C15—C14—H14	120.5
O1—C7—C6	121.0 (3)	C14—C15—C10	120.7 (4)
C8—C7—C6	118.2 (3)	C14—C15—H15	119.7
C9—C8—C7	122.4 (3)	C10—C15—H15	119.7
C9—C8—Br1	124.4 (3)

C6—C1—C2—C3	−0.6 (5)	O1—C7—C8—Br1	31.2 (5)
C1—C2—C3—C4	1.4 (5)	C6—C7—C8—Br1	−151.1 (3)
C1—C2—C3—Cl1	−176.1 (3)	C7—C8—C9—C10	174.4 (4)
C2—C3—C4—C5	−1.3 (5)	Br1—C8—C9—C10	−1.5 (6)
Cl1—C3—C4—C5	176.2 (3)	C8—C9—C10—C11	165.5 (4)
C3—C4—C5—C6	0.2 (5)	C8—C9—C10—C15	−15.5 (7)
C2—C1—C6—C5	−0.4 (5)	C15—C10—C11—C12	−0.4 (6)
C2—C1—C6—C7	174.1 (3)	C9—C10—C11—C12	178.7 (3)
C4—C5—C6—C1	0.6 (5)	C10—C11—C12—C13	−2.0 (6)
C4—C5—C6—C7	−174.3 (3)	C11—C12—C13—C14	2.5 (5)
C1—C6—C7—O1	−149.5 (4)	C11—C12—C13—Cl2	−178.3 (3)
C5—C6—C7—O1	25.2 (5)	C12—C13—C14—C15	−0.5 (5)
C1—C6—C7—C8	32.8 (5)	Cl2—C13—C14—C15	−179.6 (3)
C5—C6—C7—C8	−152.5 (3)	C13—C14—C15—C10	−2.1 (5)
O1—C7—C8—C9	−145.1 (4)	C11—C10—C15—C14	2.5 (5)
C6—C7—C8—C9	32.6 (5)	C9—C10—C15—C14	−176.5 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···O1ⁱ	0.95	2.47	3.411 (5)	171
C11—H11···Cl1ⁱⁱ	0.95	2.81	3.619 (4)	143
C15—H15···Br1	0.95	2.69	3.377 (4)	129

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

Experimental details

Crystal data
Chemical formula	C₁₅H₉BrCl₂O
M_r	356.03
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	120
a, b, c (Å)	7.7416 (3), 9.7981 (4), 9.6717 (3)
β (°)	109.075 (2)
V (Å³)	693.34 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	3.34
Crystal size (mm)	0.18 × 0.16 × 0.06

Data collection
Diffractometer	Nonius KappaCCD
Absorption correction	Multi-scan (SADABS; Bruker, 2003)
T_min, T_max	0.585, 0.824
No. of measured, independent and observed [I > 2σ(I)] reflections	12526, 3129, 2873
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.079, 1.04
No. of reflections	3129
No. of parameters	172
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.20, −0.46
Absolute structure	Flack (1983), 1434 Friedel pairs
Absolute structure parameter	0.044 (9)

Computer programs: COLLECT (Nonius, 1998), DENZO and SCALEPACK (Otwinowski & Minor, 1997) and SORTAV (Blessing, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Selected torsion angles (º) top

C6—C7—C8—C9	32.6 (5)	C7—C8—C9—C10	174.4 (4)
O1—C7—C8—Br1	31.2 (5)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···O1ⁱ	0.95	2.47	3.411 (5)	171
C11—H11···Cl1ⁱⁱ	0.95	2.81	3.619 (4)	143
C15—H15···Br1	0.95	2.69	3.377 (4)	129

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

Acknowledgements

We thank the EPSRC UK National Crystallography Service (University of Southampton) for the data collection.

References

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