(E)-1-(4-Bromo­phen­yl)-3-(2-meth­oxy­phen­yl)prop-2-en-1-one

Jasinski, J.P.; Pek, A.E.; Narayana, B.; Kamath, P.K.; Yathirajan, H.S.

doi:10.1107/S1600536810026814

organic compounds

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ISSN: 2056-9890

Volume 66| Part 8| August 2010| Page o1995

https://doi.org/10.1107/S1600536810026814

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(E)-1-(4-Bromophenyl)-3-(2-methoxyphenyl)prop-2-en-1-one

Jerry P. Jasinski,^a ^* Albert E. Pek,^a B. Narayana,^b Prakash K. Kamath ^c and H. S. Yathirajan ^d

^aDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, ^bDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, ^cDepartment of Studies in Physics, Mangalore University, Mangalagangotri 574 199, India, and ^dDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India
^*Correspondence e-mail: jjasinski@keene.edu

(Received 5 July 2010; accepted 6 July 2010; online 14 July 2010)

In the title compound, C₁₆H₁₃BrO₂, the dihedral angle between the mean planes of the methoxy- and bromo-substituted benzene rings is 24.6 (1)°. The angles between the mean plane of the prop-2-en-1-one group and the 4-bromophenyl and 2-methoxyphenyl ring planes are 18.8 (1) and 6.0 (1)°, respectively.

Related literature

For the use of chalcone compounds or chalcone-rich plant extracts as drugs or food preservatives, see: Dhar (1981 ). For the anti-inflammatory, antimicrobial, antifungal, antioxidant, cytotoxic, and anticancer activity of chalcones, see: Dimmock et al. (1999 ). For their high antimalarial activity, see: Troeberg et al. (2000 ). For SHG conversion efficiencies, see: Sarojini et al. (2006 ). For related structures, see: Arai et al. (1994 ); Shettigar et al. (2006 ); Rosli et al. (2006 ); Ng et al. (2006 ); Harrison et al. (2006 ); Patil et al. (2007 ); Li et al. (1992 ); Loh et al. (2010 ). For standard bond lengths, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₆H₁₃BrO₂
M_r = 317.17
Monoclinic, P 2₁ /n
a = 17.729 (4) Å
b = 4.3505 (9) Å
c = 19.335 (4) Å
β = 116.93 (3)°
V = 1329.6 (5) Å³
Z = 4
Mo Kα radiation
μ = 3.09 mm⁻¹
T = 100 K
0.55 × 0.50 × 0.35 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.674, T_max = 0.746
19884 measured reflections
4121 independent reflections
3635 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.024
wR(F²) = 0.070
S = 1.32
4121 reflections
173 parameters
H-atom parameters constrained
Δρ_max = 0.67 e Å⁻³
Δρ_min = −0.22 e Å⁻³

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

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810026814/ci5129sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810026814/ci5129Isup2.hkl

checkCIF report

Comment top

Chalcones belong to the flavonoid family. Chemically they consist of open-chain flavonoids in which the two aromatic rings are joined by a three-carbon, α-unsaturated carbonyl system. 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 et al., 1981). Chalcones have been reported to possess many useful properties, including anti-inflammatory, antimicrobial, antifungal, antioxidant, cytotoxic, anticancer activities (Dimmock et al., 1999). Many chalcones have been described for their high antimalarial activity (Troeberg et al., 2000). Chalcones are finding applications as organic non-linear optical materials (NLO) due to their good SHG conversion efficiencies (Sarojini et al., 2006). The crystal structures of closely related chalcones, viz. 4-bromo-4'-methoxychalcone (Li et al., 1992), 4-bromo-4'-methoxychalcone (Arai et al., 1994), 1-(4-bromophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one (Shettigar et al., 2006), 1-(4-bromophenyl)-3-(2,5-dimethoxyphenyl) prop-2-en-1-one, (Rosli et al., 2006), 1-(4-bromophenyl)-3-(3,4-dimethoxyphenyl)prop-2-en-1-one (Ng et al., 2006), (2E)-3-(1,3-benzodioxol-5-yl)-1-(4-bromophenyl)prop-2-en-1-one (Harrison et al., 2006), and 1-(4-bromophenyl)-3-(3-methoxyphenyl)prop-2-en-1-one (Patil et al., 2007) and (E)-1-(6-chloro-2-methyl-4-phenyl-3-quinolyl)-3- (2-methoxyphenyl)prop-2-en-1-one (Loh et al., 2010) have been reported. Hence in continuation with the synthesis and crystal structure determination and also owing to the importance of chalcones, the title new bromo chalcone is synthesized and its crystal structure is reported.

The title compound is a chalcone derivative with 4-bromophenyl and 2-methoxy rings bonded at the opposite ends of a propenone group, the biologically active region (Fig 1). The dihedral angle between the mean planes of the bromo and methoxy substituted benzene rings is 24.6 (1)°. The methoxy (C16—O2—C15—C14 = -2.5 (2)°) substituted benzene ring is virtually planar to the prop-2-en-1-one group (dihedral angle = 6.0 (1)°), whereas the bromo substituted benzene ring attached to the prop-2-en-1-one is slightly twisted (O1—C7—C1—C2 = -16.7 (2)°). Bond distances and angles are in normal ranges (Allen et al., 1987).

Related literature top

For the use of chalcone compounds or chalcone-rich plant extracts as drugs or food preservatives, see: Dhar et al. (1981). For the anti-inflammatory, antimicrobial, antifungal, antioxidant, cytotoxic, and anticancer activity of chalcones, see: Dimmock et al. (1999). For their high antimalarial activity, see: Troeberg et al. (2000). For SHG conversion efficiencies, see: Sarojini et al. (2006). For related structures, see: Arai et al. (1994); Shettigar et al. (2006); Rosli et al. (2006); Ng et al. (2006); Harrison et al. (2006); Patil et al. (2007); Li et al. (1992); Loh et al. (2010). For standard bond lengths, see: Allen et al. (1987).

Experimental top

To a mixture of 4-bromoacetophenone (0.01 mol, 1.99 g) and 2-methoxybenzaldehyde (0.01 mol, 1.36 g) in 30 ml of ethanol, 7 ml of 30% KOH solution was added. The mixture was stirred for 6 h at room temperature and the precipitate was collected by filtration and purified by recrystallization from ethanol. Single crystals were grown from a acetone-toluene(1:1 v/v) mixture by the slow evaporation method (m.p.329–331 K). Analytical data: found (calculated): C 60.48 (60.59%), H 4.27 (4.13%).

Structure description top

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); 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).

Figures top

Fig. 1. Molecular structure of C₁₆H₁₃BrO₂, showing the atom labeling scheme and 50% probability displacement ellipsoids.

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

Crystal data top

C₁₆H₁₃BrO₂	F(000) = 640
M_r = 317.17	D_x = 1.584 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -p 2yn	Cell parameters from 6810 reflections
a = 17.729 (4) Å	θ = 2.4–31.2°
b = 4.3505 (9) Å	µ = 3.09 mm⁻¹
c = 19.335 (4) Å	T = 100 K
β = 116.93 (3)°	Block, yellow
V = 1329.6 (5) Å³	0.55 × 0.50 × 0.35 mm
Z = 4

Data collection top

Bruker APEXII CCD area-detector diffractometer	4121 independent reflections
Radiation source: fine-focus sealed tube	3635 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ω scans	θ_max = 31.3°, θ_min = 1.3°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −25→25
T_min = 0.674, T_max = 0.746	k = −6→6
19884 measured reflections	l = −27→28

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.024	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.070	H-atom parameters constrained
S = 1.32	w = 1/[σ²(F_o²) + (0.0363P)²] where P = (F_o² + 2F_c²)/3
4121 reflections	(Δ/σ)_max = 0.002
173 parameters	Δρ_max = 0.67 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Crystal data top

C₁₆H₁₃BrO₂	V = 1329.6 (5) Å³
M_r = 317.17	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 17.729 (4) Å	µ = 3.09 mm⁻¹
b = 4.3505 (9) Å	T = 100 K
c = 19.335 (4) Å	0.55 × 0.50 × 0.35 mm
β = 116.93 (3)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	4121 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	3635 reflections with I > 2σ(I)
T_min = 0.674, T_max = 0.746	R_int = 0.025
19884 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	0 restraints
wR(F²) = 0.070	H-atom parameters constrained
S = 1.32	Δρ_max = 0.67 e Å⁻³
4121 reflections	Δρ_min = −0.22 e Å⁻³
173 parameters

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
Br1	0.945523 (8)	−0.41655 (3)	0.378517 (7)	0.02597 (6)
O1	0.68442 (7)	0.3686 (3)	0.49024 (6)	0.0336 (2)
O2	0.43404 (7)	0.9395 (2)	0.39362 (6)	0.0264 (2)
C1	0.73529 (8)	0.1076 (3)	0.41311 (7)	0.0189 (2)
C2	0.81716 (8)	0.0874 (3)	0.47366 (7)	0.0220 (2)
H2	0.8298	0.1829	0.5207	0.026*
C3	0.88004 (8)	−0.0719 (3)	0.46513 (7)	0.0231 (3)
H3	0.9346	−0.0823	0.5056	0.028*
C4	0.85962 (8)	−0.2161 (3)	0.39466 (7)	0.0205 (2)
C5	0.77855 (8)	−0.2084 (3)	0.33435 (7)	0.0218 (2)
H5	0.7657	−0.3108	0.2881	0.026*
C6	0.71655 (8)	−0.0455 (3)	0.34384 (7)	0.0208 (2)
H6	0.6618	−0.0383	0.3035	0.025*
C7	0.67125 (8)	0.2954 (3)	0.42458 (7)	0.0217 (2)
C8	0.59523 (8)	0.3990 (3)	0.35504 (7)	0.0220 (2)
H8	0.5869	0.3352	0.3062	0.026*
C9	0.53875 (9)	0.5816 (3)	0.36129 (7)	0.0228 (2)
H9	0.5472	0.6243	0.4114	0.027*
C10	0.46472 (7)	0.7234 (3)	0.29846 (7)	0.0200 (2)
C11	0.44482 (8)	0.6850 (3)	0.22024 (7)	0.0236 (2)
H11	0.4792	0.5618	0.2070	0.028*
C12	0.37500 (9)	0.8268 (3)	0.16228 (7)	0.0261 (3)
H12	0.3627	0.7990	0.1106	0.031*
C13	0.32339 (9)	1.0104 (3)	0.18148 (8)	0.0264 (3)
H13	0.2764	1.1052	0.1424	0.032*
C14	0.34131 (8)	1.0537 (3)	0.25838 (8)	0.0242 (3)
H14	0.3065	1.1775	0.2709	0.029*
C15	0.41145 (8)	0.9114 (3)	0.31666 (7)	0.0204 (2)
C16	0.38472 (10)	1.1365 (3)	0.41671 (9)	0.0305 (3)
H16A	0.3883	1.3440	0.4016	0.046*
H16B	0.4060	1.1269	0.4720	0.046*
H16C	0.3268	1.0706	0.3920	0.046*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.02597 (8)	0.02800 (8)	0.02547 (8)	0.00666 (5)	0.01300 (6)	0.00312 (5)
O1	0.0330 (5)	0.0476 (6)	0.0203 (4)	0.0095 (5)	0.0120 (4)	−0.0023 (4)
O2	0.0279 (5)	0.0312 (5)	0.0211 (4)	0.0059 (4)	0.0120 (4)	−0.0031 (4)
C1	0.0210 (6)	0.0194 (5)	0.0173 (5)	−0.0001 (4)	0.0097 (4)	0.0022 (4)
C2	0.0236 (6)	0.0248 (6)	0.0168 (5)	−0.0009 (5)	0.0086 (5)	0.0000 (4)
C3	0.0215 (6)	0.0266 (6)	0.0189 (5)	0.0007 (5)	0.0071 (5)	0.0027 (4)
C4	0.0236 (6)	0.0185 (5)	0.0217 (5)	0.0022 (4)	0.0122 (4)	0.0037 (4)
C5	0.0262 (6)	0.0204 (6)	0.0187 (5)	0.0006 (5)	0.0101 (5)	−0.0001 (4)
C6	0.0217 (6)	0.0203 (6)	0.0184 (5)	−0.0017 (4)	0.0074 (4)	0.0001 (4)
C7	0.0226 (6)	0.0233 (6)	0.0203 (5)	−0.0004 (5)	0.0108 (4)	0.0001 (4)
C8	0.0222 (6)	0.0245 (6)	0.0193 (5)	−0.0009 (5)	0.0092 (4)	−0.0015 (4)
C9	0.0222 (6)	0.0267 (6)	0.0200 (5)	−0.0026 (5)	0.0100 (5)	−0.0039 (4)
C10	0.0187 (5)	0.0203 (5)	0.0214 (5)	−0.0033 (4)	0.0094 (4)	−0.0028 (4)
C11	0.0253 (6)	0.0236 (6)	0.0234 (6)	−0.0033 (5)	0.0124 (5)	−0.0046 (5)
C12	0.0304 (7)	0.0261 (6)	0.0190 (5)	−0.0047 (5)	0.0089 (5)	−0.0015 (5)
C13	0.0233 (6)	0.0246 (6)	0.0260 (6)	−0.0021 (5)	0.0064 (5)	0.0015 (5)
C14	0.0217 (6)	0.0222 (6)	0.0284 (6)	−0.0010 (5)	0.0110 (5)	−0.0013 (5)
C15	0.0203 (6)	0.0197 (6)	0.0217 (6)	−0.0038 (4)	0.0100 (5)	−0.0031 (4)
C16	0.0345 (7)	0.0325 (7)	0.0310 (7)	0.0052 (6)	0.0206 (6)	−0.0036 (5)

Geometric parameters (Å, º) top

Br1—C4	1.8993 (13)	C8—H8	0.93
O1—C7	1.2243 (16)	C9—C10	1.4611 (18)
O2—C15	1.3600 (15)	C9—H9	0.93
O2—C16	1.4325 (16)	C10—C11	1.3987 (17)
C1—C6	1.3945 (17)	C10—C15	1.4090 (17)
C1—C2	1.3950 (18)	C11—C12	1.383 (2)
C1—C7	1.4946 (17)	C11—H11	0.93
C2—C3	1.3846 (19)	C12—C13	1.386 (2)
C2—H2	0.93	C12—H12	0.93
C3—C4	1.3907 (17)	C13—C14	1.3853 (19)
C3—H3	0.93	C13—H13	0.93
C4—C5	1.3817 (18)	C14—C15	1.3894 (18)
C5—C6	1.3882 (18)	C14—H14	0.93
C5—H5	0.93	C16—H16A	0.96
C6—H6	0.93	C16—H16B	0.96
C7—C8	1.4787 (18)	C16—H16C	0.96
C8—C9	1.3259 (18)

C15—O2—C16	118.42 (11)	C8—C9—H9	116.3
C6—C1—C2	118.74 (12)	C10—C9—H9	116.3
C6—C1—C7	122.47 (11)	C11—C10—C15	118.03 (11)
C2—C1—C7	118.79 (11)	C11—C10—C9	122.71 (12)
C3—C2—C1	121.29 (12)	C15—C10—C9	119.25 (11)
C3—C2—H2	119.4	C12—C11—C10	121.20 (13)
C1—C2—H2	119.4	C12—C11—H11	119.4
C2—C3—C4	118.44 (12)	C10—C11—H11	119.4
C2—C3—H3	120.8	C11—C12—C13	119.82 (12)
C4—C3—H3	120.8	C11—C12—H12	120.1
C5—C4—C3	121.71 (12)	C13—C12—H12	120.1
C5—C4—Br1	118.52 (9)	C12—C13—C14	120.49 (13)
C3—C4—Br1	119.72 (10)	C12—C13—H13	119.8
C4—C5—C6	118.96 (11)	C14—C13—H13	119.8
C4—C5—H5	120.5	C13—C14—C15	119.74 (13)
C6—C5—H5	120.5	C13—C14—H14	120.1
C5—C6—C1	120.82 (12)	C15—C14—H14	120.1
C5—C6—H6	119.6	O2—C15—C14	124.01 (12)
C1—C6—H6	119.6	O2—C15—C10	115.27 (11)
O1—C7—C8	122.06 (12)	C14—C15—C10	120.73 (12)
O1—C7—C1	119.67 (12)	O2—C16—H16A	109.5
C8—C7—C1	118.20 (11)	O2—C16—H16B	109.5
C9—C8—C7	120.98 (12)	H16A—C16—H16B	109.5
C9—C8—H8	119.5	O2—C16—H16C	109.5
C7—C8—H8	119.5	H16A—C16—H16C	109.5
C8—C9—C10	127.46 (12)	H16B—C16—H16C	109.5

C6—C1—C2—C3	2.17 (18)	C7—C8—C9—C10	174.50 (12)
C7—C1—C2—C3	−177.12 (11)	C8—C9—C10—C11	−1.3 (2)
C1—C2—C3—C4	−0.75 (18)	C8—C9—C10—C15	179.82 (12)
C2—C3—C4—C5	−1.24 (18)	C15—C10—C11—C12	0.01 (19)
C2—C3—C4—Br1	176.31 (9)	C9—C10—C11—C12	−178.89 (13)
C3—C4—C5—C6	1.73 (18)	C10—C11—C12—C13	−0.1 (2)
Br1—C4—C5—C6	−175.85 (9)	C11—C12—C13—C14	0.2 (2)
C4—C5—C6—C1	−0.24 (18)	C12—C13—C14—C15	−0.2 (2)
C2—C1—C6—C5	−1.67 (18)	C16—O2—C15—C14	−2.45 (19)
C7—C1—C6—C5	177.60 (11)	C16—O2—C15—C10	177.64 (11)
C6—C1—C7—O1	164.07 (13)	C13—C14—C15—O2	−179.85 (12)
C2—C1—C7—O1	−16.66 (18)	C13—C14—C15—C10	0.06 (19)
C6—C1—C7—C8	−18.73 (18)	C11—C10—C15—O2	179.93 (11)
C2—C1—C7—C8	160.54 (11)	C9—C10—C15—O2	−1.13 (17)
O1—C7—C8—C9	1.3 (2)	C11—C10—C15—C14	0.01 (18)
C1—C7—C8—C9	−175.87 (12)	C9—C10—C15—C14	178.95 (11)

Experimental details

Crystal data
Chemical formula	C₁₆H₁₃BrO₂
M_r	317.17
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	17.729 (4), 4.3505 (9), 19.335 (4)
β (°)	116.93 (3)
V (Å³)	1329.6 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.09
Crystal size (mm)	0.55 × 0.50 × 0.35

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.674, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	19884, 4121, 3635
R_int	0.025
(sin θ/λ)_max (Å⁻¹)	0.730

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.070, 1.32
No. of reflections	4121
No. of parameters	173
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.67, −0.22

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

JPJ thanks Dr Matthias Zeller and the Department of Chemistry, Youngstown State University (YSU), for their assistance with the data collection. The diffractometer was funded by NSF grant No. 0087210, by Ohio Board of Regents grant CAP-491, and by YSU. BN thanks UGC for a SAP chemical grant and KPK thanks the UGC for a teacher fellowship under the Faculty Improvement Programme. HSY thanks the UOM for sabbatical leave.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1–19. CSD CrossRef Web of Science Google Scholar
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