(3-Benzoyl­phen­yl)(phen­yl)methanone

Raza Ahsraf, A.; Akhter, Z.; Bolte, M.

doi:10.1107/S1600536811033344

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2432

doi:10.1107/S1600536811033344

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(3-Benzoylphenyl)(phenyl)methanone

Ahmed Raza Ahsraf,^a Zareen Akhter ^a ^* and Michael Bolte ^b

^aDepartment of Chemistry, Quaid-I-Azam University, Islamabad 45320, Pakistan, and ^bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany
^*Correspondence e-mail: zareenakhter@yahoo.com

(Received 4 August 2011; accepted 16 August 2011; online 27 August 2011)

Molecules of the title compound, C₂₀H₁₄O₂, show approximate C_s symmetry with the approximate mirror plane perpendicular to the central ring. The torsion angles about the acyclic bonds are 30.05 (15) and 30.77 (15)° in one half compared to −36.62 (14) and −18.60 (15)° in the other half of the molecule. The central aromatic ring makes dihedral angles of 47.78 (4) and 51.68 (3)° with the two terminal rings.

Related literature

For background to diarylketones, see: Olah (1964 ); Szmant (1989 ); March (1992 ). For the synthesis of benzoylbenzene and its derivatives, see: Karrer et al. (2000 ); Kowalski et al. (2005 ). For its natural occurrence, see: Baggett et al. (2005 ); Chiang et al. (2003 ); Bernardi, et al. (2005 ); Kulanthaivel et al. (1993 ); Iijima et al. (2004 ). For applications of these compounds, see: Bohm et al. (2001 ); Chan et al. (2004 ); Bagheri et al. (2000 ); Husain et al. (2006 ).

Experimental

Crystal data

C₂₀H₁₄O₂
M_r = 286.31
Orthorhombic, P b c a
a = 16.2029 (5) Å
b = 7.8648 (4) Å
c = 22.8422 (8) Å
V = 2910.8 (2) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 173 K
0.45 × 0.45 × 0.43 mm

Data collection

Stoe IPDS II two-circle diffractometer
40513 measured reflections
3653 independent reflections
3095 reflections with I > 2σ(I)
R_int = 0.050

Refinement

R[F² > 2σ(F²)] = 0.037
wR(F²) = 0.101
S = 1.05
3653 reflections
200 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.15 e Å⁻³

Data collection: X-AREA (Stoe & Cie, 2001 ); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811033344/fy2021sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811033344/fy2021Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811033344/fy2021Isup3.cml

checkCIF report

Comment top

Dibenzoylbenzene represents the class of diarylketones in which a carbonyl group is present between two phenyl rings. The parent diarylketone is benzoylbenzene, which is also known as benzophenone and is a widely used as a building block in organic synthesis. Benzoylbenzene and its derivatives are important chemicals or intermediates in the dyes, pharmaceutical, pesticide and other chemical industries (Olah, 1964; Szmant, 1989; March, 1992). In the pharmaceutical industry, these are used as farnesyltransferase inhibitors (Bohm et al., 2001) and non-nucleoside reverse transcriptase inhibitors of HIV-1 (Chan et al., 2004) and are renowned to be effective anesthetics (Husain et al., 2006) and the strongest photosensitizer among non-steroidal anti-inflammatory drugs (Bagheri et al., 2000). In the fragrance industry, benzoylbenzene is a useful additive in perfumes, colognes and scented soaps. Symmetrical and unsymmetrical benzoylbenzenes functionalized with electron-donating or withdrawing groups are found in a large number of plants of the Guttiferae family (Baggett et al., 2005; Chiang et al., 2003). In the past few decades, numerous natural products bearing a benzoylbenzene architecture have been reported such as cariphenones A and B (Bernardi et al., 2005), balanol (Kulanthaivel et al., 1993), and pestalone (Iijima et al., 2004). The chemistry of symmetrical and unsymmetrical benzoylbenzene includes many synthetic methods. Generally benzoylbenzene and its derivatives are prepared via Friedel–Crafts acylation of aromatic compounds catalyzed by Lewis acids, such as AlCl₃, BF₃, TiCl₄, or ZnCl₂ (Karrer et al., 2000; Kowalski et al., 2005). The title compound was synthesized successfully in an attempt to prepare dibenzoylbenzene compounds.

Related literature top

For background to diarylketones, see: Olah (1964); Szmant (1989); March (1992). For the synthesis of benzoylbenzene and its derivatives, see: Karrer et al. (2000); Kowalski et al. (2005). For its natural occurrence, see: Baggett et al. (2005); Chiang et al. (2003); Bernardi, et al. (2005); Kulanthaivel et al. (1993); Iijima et al. (2004). For applications of these compounds, see: Bohm et al. (2001); Chan et al. (2004); Bagheri et al. (2000); Husain et al. (2006).

Experimental top

For the synthesis of 1,3-dibenzoylbenzene, a 250 ml three-necked round bottomed flask equipped with a thermometer and a magnetic stirrer was charged with 20 milliliters of benzene and 19 g (0.15 mole) of anhydrous aluminium chloride (AlCl₃). Then 9 g (0.044 mole) of isophathaloyl chloride was gradually added into the flask over a period of 2 h. During this addition, the temperature of the reaction mixture was maintained at 285–291 K. After the addition was complete, the reaction was continued at 291 K for another 4 h. The mixture was slowly heated to 313 K and kept at that temperature for 2h. Finally, the reaction mixture was cooled and poured into 200 ml of aqueous HCl solution. Some white solid precipitated out, which was filtered, washed with ethanol and the crude product obtained was recrystallized from petroleum ether (b.p. 333–363 K). The related yield is 80% and melting point of the product is 378 K. For the growth of single crystals the compound was dissolved in petroleum ether (b.p. 333–363 K) and set aside for crystallization.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. Molecular structure of title compound. Displacement ellipsoids are drawn at the 50% probability level.

(3-Benzoylphenyl)(phenyl)methanone top

Crystal data top

C₂₀H₁₄O₂	F(000) = 1200
M_r = 286.31	D_x = 1.307 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 32870 reflections
a = 16.2029 (5) Å	θ = 2.7–28.7°
b = 7.8648 (4) Å	µ = 0.08 mm⁻¹
c = 22.8422 (8) Å	T = 173 K
V = 2910.8 (2) Å³	Block, colourless
Z = 8	0.45 × 0.45 × 0.43 mm

Data collection top

Stoe IPDS II two-circle diffractometer	3095 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.050
Graphite monochromator	θ_max = 28.4°, θ_min = 3.0°
ω scans	h = −21→21
40513 measured reflections	k = −10→10
3653 independent reflections	l = −29→30

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H-atom parameters constrained
wR(F²) = 0.101	w = 1/[σ²(F_o²) + (0.0547P)² + 0.4425P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max = 0.001
3653 reflections	Δρ_max = 0.28 e Å⁻³
200 parameters	Δρ_min = −0.15 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0128 (12)

Crystal data top

C₂₀H₁₄O₂	V = 2910.8 (2) Å³
M_r = 286.31	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 16.2029 (5) Å	µ = 0.08 mm⁻¹
b = 7.8648 (4) Å	T = 173 K
c = 22.8422 (8) Å	0.45 × 0.45 × 0.43 mm

Data collection top

Stoe IPDS II two-circle diffractometer	3095 reflections with I > 2σ(I)
40513 measured reflections	R_int = 0.050
3653 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.037	0 restraints
wR(F²) = 0.101	H-atom parameters constrained
S = 1.05	Δρ_max = 0.28 e Å⁻³
3653 reflections	Δρ_min = −0.15 e Å⁻³
200 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
O1	0.57553 (5)	0.26790 (13)	0.50072 (4)	0.0480 (2)
O2	0.72489 (5)	0.52781 (15)	0.23112 (4)	0.0539 (3)
C1	0.60337 (6)	0.42835 (12)	0.41666 (4)	0.0262 (2)
C2	0.60051 (6)	0.42295 (12)	0.35545 (4)	0.0259 (2)
H2	0.5597	0.3564	0.3363	0.031*
C3	0.65756 (6)	0.51526 (13)	0.32241 (4)	0.0286 (2)
C4	0.71769 (6)	0.61245 (13)	0.35094 (5)	0.0334 (2)
H4	0.7570	0.6743	0.3286	0.040*
C5	0.72029 (7)	0.61901 (13)	0.41153 (5)	0.0347 (2)
H5	0.7607	0.6866	0.4306	0.042*
C6	0.66382 (6)	0.52687 (13)	0.44426 (5)	0.0304 (2)
H6	0.6662	0.5306	0.4858	0.036*
C7	0.54757 (6)	0.32464 (13)	0.45492 (4)	0.0293 (2)
C8	0.65929 (7)	0.50879 (14)	0.25675 (5)	0.0338 (2)
C11	0.45990 (6)	0.29171 (12)	0.43842 (4)	0.0268 (2)
C12	0.41725 (6)	0.38926 (13)	0.39722 (4)	0.0303 (2)
H12	0.4445	0.4802	0.3778	0.036*
C13	0.33493 (7)	0.35381 (15)	0.38441 (5)	0.0365 (2)
H13	0.3063	0.4198	0.3561	0.044*
C14	0.29496 (7)	0.22188 (15)	0.41305 (6)	0.0400 (3)
H14	0.2388	0.1978	0.4044	0.048*
C15	0.33652 (7)	0.12507 (14)	0.45422 (5)	0.0378 (3)
H15	0.3089	0.0347	0.4736	0.045*
C16	0.41827 (6)	0.15987 (13)	0.46714 (5)	0.0312 (2)
H16	0.4463	0.0938	0.4957	0.037*
C21	0.58125 (6)	0.47839 (13)	0.22351 (4)	0.0300 (2)
C22	0.50446 (7)	0.53230 (13)	0.24428 (5)	0.0313 (2)
H22	0.5006	0.5873	0.2812	0.038*
C23	0.43365 (7)	0.50573 (15)	0.21107 (5)	0.0371 (2)
H23	0.3815	0.5417	0.2254	0.044*
C24	0.43937 (8)	0.42670 (15)	0.15702 (5)	0.0400 (3)
H24	0.3910	0.4086	0.1344	0.048*
C25	0.51537 (9)	0.37388 (15)	0.13580 (5)	0.0414 (3)
H25	0.5190	0.3199	0.0987	0.050*
C26	0.58596 (8)	0.39992 (15)	0.16880 (5)	0.0375 (3)
H26	0.6380	0.3641	0.1541	0.045*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0428 (5)	0.0614 (6)	0.0398 (5)	−0.0123 (4)	−0.0126 (4)	0.0191 (4)
O2	0.0303 (4)	0.0890 (7)	0.0425 (5)	−0.0035 (4)	0.0115 (4)	0.0008 (5)
C1	0.0234 (4)	0.0247 (4)	0.0305 (5)	0.0028 (3)	−0.0006 (4)	−0.0009 (4)
C2	0.0228 (4)	0.0243 (4)	0.0307 (5)	0.0014 (3)	−0.0005 (4)	−0.0021 (4)
C3	0.0241 (5)	0.0278 (5)	0.0338 (5)	0.0032 (4)	0.0029 (4)	−0.0005 (4)
C4	0.0251 (5)	0.0303 (5)	0.0448 (6)	−0.0021 (4)	0.0041 (4)	−0.0002 (4)
C5	0.0273 (5)	0.0323 (5)	0.0444 (6)	−0.0034 (4)	−0.0023 (4)	−0.0075 (4)
C6	0.0268 (5)	0.0308 (5)	0.0336 (5)	0.0027 (4)	−0.0029 (4)	−0.0049 (4)
C7	0.0290 (5)	0.0301 (5)	0.0287 (5)	−0.0004 (4)	−0.0017 (4)	0.0011 (4)
C8	0.0283 (5)	0.0387 (5)	0.0344 (5)	0.0019 (4)	0.0063 (4)	0.0018 (4)
C11	0.0256 (5)	0.0274 (4)	0.0273 (4)	0.0014 (4)	0.0024 (3)	−0.0031 (4)
C12	0.0285 (5)	0.0316 (5)	0.0310 (5)	0.0020 (4)	0.0018 (4)	0.0003 (4)
C13	0.0298 (5)	0.0404 (6)	0.0393 (6)	0.0054 (4)	−0.0045 (4)	−0.0026 (5)
C14	0.0268 (5)	0.0412 (6)	0.0520 (7)	−0.0019 (4)	−0.0020 (5)	−0.0085 (5)
C15	0.0321 (5)	0.0326 (5)	0.0487 (6)	−0.0049 (4)	0.0081 (5)	−0.0024 (5)
C16	0.0311 (5)	0.0285 (5)	0.0340 (5)	0.0014 (4)	0.0039 (4)	0.0002 (4)
C21	0.0314 (5)	0.0305 (5)	0.0282 (5)	−0.0004 (4)	0.0046 (4)	0.0032 (4)
C22	0.0315 (5)	0.0325 (5)	0.0299 (5)	0.0023 (4)	0.0019 (4)	0.0011 (4)
C23	0.0328 (5)	0.0389 (6)	0.0394 (6)	−0.0002 (4)	−0.0020 (4)	0.0079 (5)
C24	0.0467 (7)	0.0364 (6)	0.0369 (5)	−0.0107 (5)	−0.0092 (5)	0.0086 (5)
C25	0.0601 (8)	0.0362 (6)	0.0278 (5)	−0.0078 (5)	0.0007 (5)	0.0007 (4)
C26	0.0435 (6)	0.0388 (6)	0.0302 (5)	0.0000 (5)	0.0097 (4)	0.0011 (4)

Geometric parameters (Å, º) top

O1—C7	1.2242 (12)	C12—H12	0.9500
O2—C8	1.2227 (13)	C13—C14	1.3870 (17)
C1—C6	1.3989 (14)	C13—H13	0.9500
C1—C2	1.3995 (13)	C14—C15	1.3847 (17)
C1—C7	1.4990 (14)	C14—H14	0.9500
C2—C3	1.3969 (14)	C15—C16	1.3844 (15)
C2—H2	0.9500	C15—H15	0.9500
C3—C4	1.3993 (15)	C16—H16	0.9500
C3—C8	1.5009 (15)	C21—C26	1.3958 (15)
C4—C5	1.3857 (16)	C21—C22	1.3975 (14)
C4—H4	0.9500	C22—C23	1.3913 (16)
C5—C6	1.3861 (15)	C22—H22	0.9500
C5—H5	0.9500	C23—C24	1.3852 (17)
C6—H6	0.9500	C23—H23	0.9500
C7—C11	1.4923 (14)	C24—C25	1.3870 (19)
C8—C21	1.4942 (15)	C24—H24	0.9500
C11—C12	1.3970 (14)	C25—C26	1.3851 (18)
C11—C16	1.4002 (14)	C25—H25	0.9500
C12—C13	1.3937 (15)	C26—H26	0.9500

C6—C1—C2	119.36 (9)	C14—C13—C12	119.83 (10)
C6—C1—C7	117.45 (9)	C14—C13—H13	120.1
C2—C1—C7	123.09 (9)	C12—C13—H13	120.1
C3—C2—C1	120.13 (9)	C15—C14—C13	120.31 (10)
C3—C2—H2	119.9	C15—C14—H14	119.8
C1—C2—H2	119.9	C13—C14—H14	119.8
C2—C3—C4	119.54 (9)	C16—C15—C14	120.09 (10)
C2—C3—C8	122.32 (9)	C16—C15—H15	120.0
C4—C3—C8	118.09 (9)	C14—C15—H15	120.0
C5—C4—C3	120.44 (10)	C15—C16—C11	120.49 (10)
C5—C4—H4	119.8	C15—C16—H16	119.8
C3—C4—H4	119.8	C11—C16—H16	119.8
C4—C5—C6	119.95 (10)	C26—C21—C22	119.12 (10)
C4—C5—H5	120.0	C26—C21—C8	118.65 (10)
C6—C5—H5	120.0	C22—C21—C8	122.17 (9)
C5—C6—C1	120.57 (10)	C23—C22—C21	120.23 (10)
C5—C6—H6	119.7	C23—C22—H22	119.9
C1—C6—H6	119.7	C21—C22—H22	119.9
O1—C7—C11	120.32 (9)	C24—C23—C22	119.88 (11)
O1—C7—C1	118.25 (9)	C24—C23—H23	120.1
C11—C7—C1	121.42 (8)	C22—C23—H23	120.1
O2—C8—C21	120.79 (10)	C23—C24—C25	120.34 (11)
O2—C8—C3	119.38 (10)	C23—C24—H24	119.8
C21—C8—C3	119.83 (9)	C25—C24—H24	119.8
C12—C11—C16	118.95 (9)	C26—C25—C24	119.91 (10)
C12—C11—C7	123.07 (9)	C26—C25—H25	120.0
C16—C11—C7	117.95 (9)	C24—C25—H25	120.0
C13—C12—C11	120.33 (10)	C25—C26—C21	120.50 (11)
C13—C12—H12	119.8	C25—C26—H26	119.8
C11—C12—H12	119.8	C21—C26—H26	119.8

C6—C1—C2—C3	−0.02 (14)	C1—C7—C11—C16	163.41 (9)
C7—C1—C2—C3	−176.19 (9)	C16—C11—C12—C13	−0.95 (15)
C1—C2—C3—C4	0.26 (14)	C7—C11—C12—C13	−178.93 (10)
C1—C2—C3—C8	177.63 (9)	C11—C12—C13—C14	0.51 (16)
C2—C3—C4—C5	−0.73 (15)	C12—C13—C14—C15	−0.12 (17)
C8—C3—C4—C5	−178.22 (9)	C13—C14—C15—C16	0.18 (17)
C3—C4—C5—C6	0.96 (16)	C14—C15—C16—C11	−0.63 (16)
C4—C5—C6—C1	−0.72 (16)	C12—C11—C16—C15	1.01 (15)
C2—C1—C6—C5	0.25 (15)	C7—C11—C16—C15	179.09 (10)
C7—C1—C6—C5	176.64 (9)	O2—C8—C21—C26	27.69 (16)
C6—C1—C7—O1	−32.33 (14)	C3—C8—C21—C26	−151.99 (10)
C2—C1—C7—O1	143.91 (11)	O2—C8—C21—C22	−149.55 (12)
C6—C1—C7—C11	147.13 (9)	C3—C8—C21—C22	30.77 (15)
C2—C1—C7—C11	−36.62 (14)	C26—C21—C22—C23	0.87 (15)
C2—C3—C8—O2	−149.63 (11)	C8—C21—C22—C23	178.10 (10)
C4—C3—C8—O2	27.79 (16)	C21—C22—C23—C24	−0.48 (16)
C2—C3—C8—C21	30.05 (15)	C22—C23—C24—C25	−0.01 (17)
C4—C3—C8—C21	−152.53 (10)	C23—C24—C25—C26	0.11 (17)
O1—C7—C11—C12	160.85 (11)	C24—C25—C26—C21	0.30 (17)
C1—C7—C11—C12	−18.60 (15)	C22—C21—C26—C25	−0.78 (16)
O1—C7—C11—C16	−17.14 (15)	C8—C21—C26—C25	−178.11 (10)

Experimental details

Crystal data
Chemical formula	C₂₀H₁₄O₂
M_r	286.31
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	173
a, b, c (Å)	16.2029 (5), 7.8648 (4), 22.8422 (8)
V (Å³)	2910.8 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.45 × 0.45 × 0.43

Data collection
Diffractometer	Stoe IPDS II two-circle diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	40513, 3653, 3095
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.670

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.037, 0.101, 1.05
No. of reflections	3653
No. of parameters	200
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.15

Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Sheldrick, 2008).

Acknowledgements

The authors are grateful to the Department of Chemistry, Quaid-i-Azam University, Islamabad, Pakistan.

References

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