(2E)-3-(2-Bromo-5-methoxy­phen­yl)-1-(2,4-dichloro­phen­yl)prop-2-en-1-one

In the title mol­ecule, C₁₆H₁₁BrCl₂O₂, the angle between the mean planes of the 2,4-dichloro­phenyl and 2-bromo­phenyl groups is 45.3 (5)°. The 5-meth­oxy group, with a torsion angle of 175.4 (4)°, is twisted slightly away from the plane of the 2-bromo­phenyl ring in an anti­periplanar conformation. The ketone oxygen of the prop-2-en-1-one group is twisted in a synclinal arrangement with respect to the 2,4-dichloro­phenyl group, with a torsion angle of 54.1 (5)°. Mol­ecules pack in a chain-like fashion, in an alternate inverted pattern parallel to the bc face of the unit cell, along the c axis.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.053
• wR factor = 0.126
• Data-to-parameter ratio = 24.0

checkCIF/PLATON results

No syntax errors found



Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR') is < 0.75
            Tmin and Tmax reported:      0.305     1.000
            Tmin(prime) and Tmax expected:      0.251     0.603
            RR(prime) =      0.733
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_B Tmax/Tmin Range Test RR' too Large .............       0.67

Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.97
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.60

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.603
            Tmax scaled      0.603 Tmin scaled      0.184

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

   0 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
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Chalcones are one of the major classes of natural products with widespread distribution in fruits, vegetables, spices, tea and soy based foodstuff have been recently subjects of great interest for their interesting pharmacological activities (Di Carlo et al., 1999). A vast number of naturally occurring chalcones are polyhydroxylated in the aryl rings. The radical quenching properties of the phenolic groups present in many chalcones have raised interest in using the compounds or chalcone rich plant extracts as drugs or food preservatives (Dhar, 1981). Chalcones can be easily obtained from the aldol condensation of aromatic aldehydes and aromatic ketones. This class of compounds presents interesting biological properties such as cytotoxicity (Pandey et al., 2005; Bhat et al., 2005) and antiherpes activity and antitumour activity and may be useful for the chemotherapy of leishmaniasis among others (Lawrence et al., 2001). A review on the bioactivities of chalcones is described (Dimmock et al., 1999). Chalcones and their heterocyclic analogs as potential antifungal chemotherapeutic agents is published (Opletalova & Sedivy, 1999). Chalcones and flavonoids as anti-tuberculosis agents is reported (Lin et al., 2002). Among several organic compounds reported for NLO property, chalcone derivatives are noticeable materials for their excellent blue light transmittance and good crystallizability. They provide a necessary configuration to show NLO property with two planar rings connected through a conjugated double bond (Goto et al., 1991; Uchida et al., 1998; Tam et al., 1989; Indira et al., 2002, Sarojini et al., 2006). Substitution on either of the phenyl rings greatly influence non-centrosymmetric crystal packing. It is speculated that in order to improve the activity, more bulky substituents should be introduced to increase the spontaneous polarization of acentric crystal (Fichou et al., 1988). The molecular hyperpolarizability β are strongly influenced not only by the electronic effect but also by the steric effect of the substituent (Cho et al., 1996). Bromo groups can obviously improve the molecular first order hyperpolarizabilities and can effectively reduce the dipole-dipole interactions between the molecules (Zhao et al., 2002). The crystal structures of chalcones containing structures of a few dichloro and bromo substituted chalcones viz., (2E)-1-(2,4-dichlorophenyl)-3-(quinolin-8-yl)prop-2-en-1-one (Sarojini et al., 2007), (2E)-1-(2,4-dichlorophenyl)-3-(4,5-dimethoxy-2-nitrophenyl) prop-2-en-1-one (Yathirajan et al., 2007a), (2E)-1-(2,4-dichlorophenyl)-3-(6-methoxy-2-naphthyl) prop-2-en-1-one (Yathirajan et al., 2007b), (2E)-1-(2,4-dichlorophenyl)-3-(2-hydroxy-3-methoxyphenyl) prop-2-en-1-one (Yathirajan et al., 2007c), (2E)-1-(2,4-dichlorophenyl)-3-(4-nitrophenyl)prop-2-en-1-one (Yathirajan et al., 2007 d), (2E)-1-(2,4-dichlorophenyl)-3-(2-hydroxyphenyl)prop-2-en-1-one (Yathirajan et al., 2007 e), (2E)-1-(3-bromo-2-thienyl)-3-[4-(dimethylamino)phenyl] prop-2-en-1-one (Butcher et al., 2007a), (2E)-1-(3-bromo-2-thienyl)-3-(4-butoxyphenyl)prop-2-en-1-one (Butcher et al., 2007b), (2E)-1-(3-bromo-2-thienyl)-3-(6-methoxy-2-naphthyl)prop-2-en-1-one (Butcher et al., 2007c) and (2E)-1-(3-bromothien-2-yl)-3-phenylprop-2-en-1-one (Butcher et al., 2007 d) have been reported. In continuation of our work on chalcones, a new chalcone, (I), C₁₆H₁₁BrCl₂O₂ is synthesized and its crystal structure is reported.

The angle between the mean planes of the 2,4-dichlorophenyl and 2-bromophenyl groups is 45.3 (5)° (Fig. 1). The 5-methoxy group, with a torsion angle [C16–O2–C14–C13] of 175.4 (4)°, is twisted slightly away from the plane of the 2-bromophenyl ring in an anti-periplanar formation. The ketone oxygen of the prop-2-en-1-one group, with a 54.1 (5)° torsion angle [C2–C1–C7–O1], is twisted in a syn-clinal arrangement with the 2,4-dichlorophenyl group. Molecules in the asymmetric unit pack themselves in a chain-like fashion in an alternate inverted pattern parallel to the bc face of the unit cell along the c axis (Fig. 2). Crystal packing is stabilized by van der Waals forces as well as by interactions between π ring orbitals from a nearby 2-bromo-5-methoxyphenyl ring [C10ⁱ–C15ⁱ (Cg1ⁱ); where Cg = ring center of gravity] and H6A from the 2,4-dichlorophenyl ring [C6–H6A···Cg1ⁱ: 2.78 (0) Å (symmetry code ⁱ: 1 - x, 1 - y, 1 - z)].

Related literature

For related structures, see: Sarojini et al. 2007; Yathirajan et al. (2007a,b,c,d,e); Butcher et al., (2007a,b,c,d). For related literature, see: Dhar, (1981); Fichou et al. (1988); Tam et al. (1989); Goto et al. (1991); Cho et al. (1996); Uchida et al. (1998); Di Carlo et al. (1999); Dimmock et al. (1999); Opletalova & Sedivy, (1999); Lawrence et al. (2001); Indira et al. (2002); Lin et al. (2002); Zhao et al. (2002); Bhat et al. (2005); Pandey et al. (2005); Sarojini et al. (2006).

S2. Experimental

2-Bromo-5-methoxybenzaldehyde (2.15 g, 0.01 mol) in ethanol (30 ml) was mixed with 1-(2,4-dichlorophenyl)ethanone (1.89 g, 0.01 mol) in ethanol (20 ml) and the mixture was treated with 7 ml of 10% KOH solution (Fig. 3). The reaction mixture was then kept for constant stirring for 10 h. The solid precipitate obtained was filtered, washed with ethanol and dried. The crystal growth was carried out from a 1:1 mixture of acetone and toluene by the slow evaporation technique (m.p.: 367–369 K). Analysis found: C 49.71, H 2.83%; C₁₆H₁₁BrCl₂O₂ requires: C 49.78, H 2.87%.

S3. Refinement

All H atoms were placed in their calculated places and all H atoms were refined using a riding model with C—H = 0.93 Å, and with U_iso(H) = 1.18–1.50U_eq(C).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Bruker, 2000).

Figures

	Fig. 1. Molecular structure of the title compound, showing atom labeling and 50% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound, viewed down the a axis and showing 50% probability displacement ellipsoids.
	Fig. 3. Synthetic scheme for C16H11BrCl2O2.

(2E)-3-(2-Bromo-5-methoxyphenyl)-1-(2,4-dichlorophenyl)prop-2-en-1-one

Crystal data

C16H11BrCl2O2	Z = 2
Mr = 386.06	F(000) = 384
Triclinic, P1	Dx = 1.640 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.7836 (13) Å	Cell parameters from 4266 reflections
b = 7.8829 (8) Å	θ = 4.7–32.4°
c = 13.0927 (19) Å	µ = 2.97 mm^−1
α = 83.05 (1)°	T = 296 K
β = 88.899 (13)°	Plate, pale yellow
γ = 78.596 (11)°	0.45 × 0.37 × 0.17 mm
V = 781.68 (19) Å^3

Data collection

Oxford Diffraction Gemini R CCD diffractometer	4577 independent reflections
Radiation source: fine-focus sealed tube	2880 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.030
Detector resolution: 10.5081 pixels mm^-1	θmax = 32.4°, θmin = 4.7°
φ and ω scans	h = −11→10
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	k = −11→11
Tmin = 0.305, Tmax = 1.000	l = −18→19
8869 measured reflections

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)] = 0.053	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.126	H-atom parameters constrained
S = 1.08	w = 1/[σ^2(Fo^2) + (0.0456P)^2 + 0.6258P] where P = (Fo^2 + 2Fc^2)/3
4577 reflections	(Δ/σ)max = 0.002
191 parameters	Δρmax = 0.74 e Å^−3
0 restraints	Δρmin = −0.43 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Br	0.19344 (6)	0.81176 (4)	0.43646 (3)	0.06201 (16)
Cl1	0.24366 (16)	0.09035 (12)	0.15596 (9)	0.0728 (3)
Cl2	0.25624 (19)	0.73128 (14)	−0.02982 (8)	0.0837 (4)
O1	0.5150 (4)	0.0495 (3)	0.3339 (2)	0.0678 (8)
O2	0.1303 (4)	0.3275 (3)	0.82251 (18)	0.0643 (7)
C1	0.3892 (4)	0.3245 (4)	0.2449 (2)	0.0378 (6)
C2	0.3062 (5)	0.2898 (4)	0.1586 (2)	0.0441 (7)
C3	0.2649 (5)	0.4133 (4)	0.0736 (2)	0.0537 (9)
H3A	0.2066	0.3893	0.0173	0.064*
C4	0.3121 (5)	0.5721 (4)	0.0743 (2)	0.0513 (8)
C5	0.3987 (5)	0.6101 (4)	0.1559 (3)	0.0504 (8)
H5A	0.4322	0.7172	0.1543	0.060*
C6	0.4354 (4)	0.4865 (4)	0.2408 (2)	0.0437 (7)
H6A	0.4928	0.5125	0.2968	0.052*
C7	0.4314 (4)	0.1950 (4)	0.3399 (2)	0.0432 (7)
C8	0.3722 (4)	0.2515 (4)	0.4402 (2)	0.0417 (7)
H8A	0.4111	0.1766	0.4992	0.050*
C9	0.2675 (4)	0.4020 (4)	0.4518 (2)	0.0388 (6)
H9A	0.2245	0.4717	0.3917	0.047*
C10	0.2116 (4)	0.4711 (4)	0.5489 (2)	0.0374 (6)
C11	0.1705 (4)	0.6497 (4)	0.5541 (2)	0.0425 (7)
C12	0.1197 (5)	0.7168 (4)	0.6455 (3)	0.0496 (8)
H12A	0.0946	0.8367	0.6476	0.060*
C13	0.1066 (5)	0.6045 (5)	0.7330 (3)	0.0518 (8)
H13A	0.0708	0.6490	0.7943	0.062*
C14	0.1467 (5)	0.4245 (4)	0.7307 (2)	0.0455 (7)
C15	0.1996 (4)	0.3585 (4)	0.6394 (2)	0.0395 (6)
H15A	0.2274	0.2385	0.6379	0.047*
C16	0.1558 (8)	0.1460 (6)	0.8250 (3)	0.0852 (15)
H16A	0.1342	0.0951	0.8932	0.128*
H16B	0.2743	0.1011	0.8059	0.128*
H16C	0.0765	0.1175	0.7775	0.128*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Br	0.0796 (3)	0.03977 (19)	0.0635 (2)	−0.01194 (17)	−0.00880 (19)	0.00831 (14)
Cl1	0.0965 (8)	0.0418 (4)	0.0858 (7)	−0.0191 (5)	−0.0089 (6)	−0.0200 (4)
Cl2	0.1286 (11)	0.0601 (6)	0.0499 (5)	0.0004 (6)	−0.0125 (6)	0.0143 (4)
O1	0.090 (2)	0.0433 (13)	0.0573 (15)	0.0139 (13)	0.0105 (14)	−0.0001 (11)
O2	0.090 (2)	0.0597 (15)	0.0413 (13)	−0.0130 (14)	0.0090 (13)	−0.0039 (11)
C1	0.0424 (18)	0.0345 (14)	0.0339 (14)	−0.0026 (12)	0.0044 (12)	−0.0023 (11)
C2	0.056 (2)	0.0323 (14)	0.0449 (17)	−0.0071 (13)	0.0032 (14)	−0.0098 (12)
C3	0.069 (3)	0.0518 (19)	0.0388 (17)	−0.0036 (17)	−0.0066 (16)	−0.0114 (14)
C4	0.070 (2)	0.0410 (16)	0.0366 (16)	−0.0006 (16)	0.0016 (15)	0.0014 (12)
C5	0.066 (2)	0.0354 (15)	0.0494 (18)	−0.0140 (15)	0.0068 (16)	0.0003 (13)
C6	0.050 (2)	0.0421 (15)	0.0399 (16)	−0.0110 (14)	0.0002 (13)	−0.0046 (12)
C7	0.0457 (19)	0.0350 (14)	0.0456 (17)	−0.0033 (13)	0.0016 (13)	0.0003 (12)
C8	0.0462 (19)	0.0387 (15)	0.0366 (15)	−0.0026 (13)	−0.0030 (13)	0.0016 (11)
C9	0.0443 (18)	0.0368 (14)	0.0341 (14)	−0.0080 (13)	−0.0045 (12)	0.0017 (11)
C10	0.0361 (16)	0.0377 (14)	0.0378 (15)	−0.0049 (12)	−0.0044 (12)	−0.0047 (11)
C11	0.0414 (18)	0.0369 (14)	0.0487 (17)	−0.0083 (13)	−0.0080 (14)	−0.0011 (12)
C12	0.049 (2)	0.0382 (15)	0.061 (2)	−0.0019 (14)	−0.0048 (16)	−0.0122 (14)
C13	0.051 (2)	0.056 (2)	0.0474 (18)	−0.0043 (16)	0.0009 (15)	−0.0164 (15)
C14	0.049 (2)	0.0483 (17)	0.0397 (16)	−0.0110 (14)	−0.0007 (14)	−0.0051 (13)
C15	0.0413 (18)	0.0366 (14)	0.0414 (15)	−0.0091 (12)	−0.0028 (13)	−0.0050 (11)
C16	0.141 (5)	0.059 (2)	0.053 (2)	−0.021 (3)	0.018 (3)	0.0067 (18)

Geometric parameters (Å, º)

Br—C11	1.908 (3)	C8—C9	1.323 (4)
Cl1—C2	1.739 (3)	C8—H8A	0.9300
Cl2—C4	1.737 (3)	C9—C10	1.468 (4)
O1—C7	1.213 (4)	C9—H9A	0.9300
O2—C14	1.363 (4)	C10—C11	1.390 (4)
O2—C16	1.401 (5)	C10—C15	1.405 (4)
C1—C6	1.388 (4)	C11—C12	1.386 (5)
C1—C2	1.394 (4)	C12—C13	1.376 (5)
C1—C7	1.507 (4)	C12—H12A	0.9300
C2—C3	1.385 (4)	C13—C14	1.395 (5)
C3—C4	1.374 (5)	C13—H13A	0.9300
C3—H3A	0.9300	C14—C15	1.384 (4)
C4—C5	1.368 (5)	C15—H15A	0.9300
C5—C6	1.380 (4)	C16—H16A	0.9600
C5—H5A	0.9300	C16—H16B	0.9600
C6—H6A	0.9300	C16—H16C	0.9600
C7—C8	1.474 (4)
C14—O2—C16	118.4 (3)	C8—C9—H9A	116.4
C6—C1—C2	117.2 (3)	C10—C9—H9A	116.4
C6—C1—C7	119.7 (3)	C11—C10—C15	118.2 (3)
C2—C1—C7	123.2 (3)	C11—C10—C9	121.0 (3)
C3—C2—C1	121.8 (3)	C15—C10—C9	120.9 (3)
C3—C2—Cl1	117.5 (3)	C12—C11—C10	121.6 (3)
C1—C2—Cl1	120.7 (2)	C12—C11—Br	117.4 (2)
C4—C3—C2	118.4 (3)	C10—C11—Br	120.9 (2)
C4—C3—H3A	120.8	C13—C12—C11	119.4 (3)
C2—C3—H3A	120.8	C13—C12—H12A	120.3
C5—C4—C3	121.8 (3)	C11—C12—H12A	120.3
C5—C4—Cl2	118.9 (3)	C12—C13—C14	120.6 (3)
C3—C4—Cl2	119.3 (3)	C12—C13—H13A	119.7
C4—C5—C6	118.8 (3)	C14—C13—H13A	119.7
C4—C5—H5A	120.6	O2—C14—C15	125.4 (3)
C6—C5—H5A	120.6	O2—C14—C13	114.9 (3)
C5—C6—C1	121.9 (3)	C15—C14—C13	119.6 (3)
C5—C6—H6A	119.0	C14—C15—C10	120.6 (3)
C1—C6—H6A	119.0	C14—C15—H15A	119.7
O1—C7—C8	121.0 (3)	C10—C15—H15A	119.7
O1—C7—C1	120.7 (3)	O2—C16—H16A	109.5
C8—C7—C1	118.3 (3)	O2—C16—H16B	109.5
C9—C8—C7	124.2 (3)	H16A—C16—H16B	109.5
C9—C8—H8A	117.9	O2—C16—H16C	109.5
C7—C8—H8A	117.9	H16A—C16—H16C	109.5
C8—C9—C10	127.2 (3)	H16B—C16—H16C	109.5
C6—C1—C2—C3	−2.5 (5)	C7—C8—C9—C10	−176.2 (3)
C7—C1—C2—C3	178.2 (3)	C8—C9—C10—C11	151.1 (3)
C6—C1—C2—Cl1	179.8 (2)	C8—C9—C10—C15	−28.3 (5)
C7—C1—C2—Cl1	0.4 (4)	C15—C10—C11—C12	0.3 (5)
C1—C2—C3—C4	1.8 (5)	C9—C10—C11—C12	−179.2 (3)
Cl1—C2—C3—C4	179.6 (3)	C15—C10—C11—Br	177.1 (2)
C2—C3—C4—C5	0.4 (6)	C9—C10—C11—Br	−2.3 (4)
C2—C3—C4—Cl2	−178.2 (3)	C10—C11—C12—C13	−1.1 (5)
C3—C4—C5—C6	−1.7 (5)	Br—C11—C12—C13	−178.0 (3)
Cl2—C4—C5—C6	176.9 (3)	C11—C12—C13—C14	1.0 (5)
C4—C5—C6—C1	0.9 (5)	C16—O2—C14—C15	−5.0 (6)
C2—C1—C6—C5	1.1 (5)	C16—O2—C14—C13	175.4 (4)
C7—C1—C6—C5	−179.5 (3)	C12—C13—C14—O2	179.4 (3)
C6—C1—C7—O1	−125.2 (4)	C12—C13—C14—C15	−0.2 (5)
C2—C1—C7—O1	54.1 (5)	O2—C14—C15—C10	179.8 (3)
C6—C1—C7—C8	53.3 (4)	C13—C14—C15—C10	−0.6 (5)
C2—C1—C7—C8	−127.4 (3)	C11—C10—C15—C14	0.6 (5)
O1—C7—C8—C9	−173.6 (3)	C9—C10—C15—C14	−180.0 (3)
C1—C7—C8—C9	8.0 (5)