2-(4-Bromo­phen­yl)-2-oxoethyl 4-meth­oxy­benzoate

Fun, H.-K.; Loh, W.-S.; Garudachari, B.; Isloor, A.M.; Satyanarayan, M.N.

doi:10.1107/S1600536811018988

organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page o1529

doi:10.1107/S1600536811018988

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2-(4-Bromophenyl)-2-oxoethyl 4-methoxybenzoate

Hoong-Kun Fun,^a ^*‡ Wan-Sin Loh,^a § B. Garudachari,^b Arun M. Isloor ^b and M. N. Satyanarayan ^c

^aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, ^bOrganic Chemistry Division, Department of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India, and ^cDepartment of Physics, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India
^*Correspondence e-mail: hkfun@usm.my

(Received 16 May 2011; accepted 19 May 2011; online 25 May 2011)

In the title compound, C₁₆H₁₃BrO₄, the benzene rings are almost perpendicular to each other, making a dihedral angle of 84.07 (8)°. In the crystal, the molecules are linked into chains along the a axis via intermolecular C—H⋯O hydrogen bonds. A C—H⋯π interaction is also observed.

Related literature

For background to and applications of phenacyl benzoates, see: Gandhi et al. (1995 ); Huang et al. (1996 ); Litera et al. (2006 ); Rather & Reid (1919 ); Ruzicka et al. (2002 ); Sheehan & Umezaw (1973 ). For the synthesis, see: Judefind & Reid (1920 ). For bond-length data, see: Allen et al. (1987 ).

Experimental

Crystal data

C₁₆H₁₃BrO₄
M_r = 349.17
Triclinic, $[P \overline 1]$
a = 7.9700 (5) Å
b = 7.9852 (5) Å
c = 11.3185 (7) Å
α = 86.536 (1)°
β = 83.205 (1)°
γ = 89.633 (1)°
V = 713.97 (8) Å³
Z = 2
Mo Kα radiation
μ = 2.89 mm⁻¹
T = 296 K
0.58 × 0.34 × 0.32 mm

Data collection

Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.286, T_max = 0.461
10671 measured reflections
3270 independent reflections
2767 reflections with I > 2σ(I)
R_int = 0.017

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.069
S = 1.05
3270 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 0.36 e Å⁻³
Δρ_min = −0.52 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2A⋯O1ⁱ	0.93	2.48	3.386 (2)	164
C11—H11A⋯Cg1ⁱⁱ	0.93	2.81	3.6395 (18)	149
Symmetry codes: (i) x-1, y, z; (ii) -x+2, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); 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 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811018988/is2716sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811018988/is2716Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811018988/is2716Isup3.cml

checkCIF report

Comment top

Phenacyl benzoates are very useful protecting groups which can be easily removed by non-chemical reactions. The advantage of photosensitive blocking groups is that they can be removed under completely neutral and mild conditions (Sheehan & Umezaw, 1973; Ruzicka et al., 2002; Litera et al., 2006) used for identification of organic acids (Rather & Reid, 1919), synthesis of oxazoles, imidazoles (Huang et al., 1996) and benzoxazepine (Gandhi et al., 1995). Keeping this in view, we hereby report the crystal structure of 2-(4-bromophenyl)-2-oxoethyl 4-methoxybenzoate of potential commercial importance.

In the title compound (Fig. 1), the C1–C6 benzene ring [maximum deviation of 0.005 (2) Å at atom C6] is almost perpendicular with the C10–C15 benzene ring [maximum deviation of 0.014 (2) Å at atom C13] with a dihedral angle of 84.07 (8)°. Bond lengths (Allen et al., 1987) and angles are within the normal ranges.

In the crystal packing (Fig. 2), the molecules are linked into chains along the a axis via intermolecular C2—H2A···O1 hydrogen bonds (Table 1). The crystal packing is further consolidated by C—H···π interactions, involving the centroids of C1–C6 phenyl ring.

Related literature top

For background to and applications of phenacyl benzoates, see: Gandhi et al. (1995); Huang et al. (1996); Litera et al. (2006); Rather & Reid (1919); Ruzicka et al. (2002); Sheehan & Umezaw (1973). For the synthesis, see: Judefind & Reid (1920). For bond-length data, see: Allen et al. (1987).

Experimental top

The mixture of 4-methoxy benzoic acid (1.0 g, 0.0065 mol) sodium carbonate (0.766 g, 0.0072 mol) and 2-bromo-1-(4-bromophenyl)ethanone (2.00 g, 0.0072 mol) in dimethyl formamide (10 ml) was stirred at room temperature for 2 h. On cooling, the separated colourless needle-shaped crystals of 2-(4-bromophenyl)-2-oxoethyl 4-methoxybenzoate were collected by filtration. Compound was recrystallized from ethanol. Yield: 2.1 g (91.70%), m.p.: 429–430 K (Judefind & Reid, 1920).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme.
	Fig. 2. The crystal packing of the title compound, viewed along the c axis. H atoms not involved in the intermolecular interactions (dashed lines) have been omitted for clarity.

2-(4-Bromophenyl)-2-oxoethyl 4-methoxybenzoate top

Crystal data top

C₁₆H₁₃BrO₄	Z = 2
M_r = 349.17	F(000) = 352
Triclinic, P1	D_x = 1.624 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.9700 (5) Å	Cell parameters from 4684 reflections
b = 7.9852 (5) Å	θ = 3.0–30.0°
c = 11.3185 (7) Å	µ = 2.89 mm⁻¹
α = 86.536 (1)°	T = 296 K
β = 83.205 (1)°	Block, colourless
γ = 89.633 (1)°	0.58 × 0.34 × 0.32 mm
V = 713.97 (8) Å³

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	3270 independent reflections
Radiation source: fine-focus sealed tube	2767 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.017
ϕ and ω scans	θ_max = 27.5°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −10→10
T_min = 0.286, T_max = 0.461	k = −10→10
10671 measured reflections	l = −14→14

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.069	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0314P)² + 0.2047P] where P = (F_o² + 2F_c²)/3
3270 reflections	(Δ/σ)_max = 0.001
191 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.52 e Å⁻³

Crystal data top

C₁₆H₁₃BrO₄	γ = 89.633 (1)°
M_r = 349.17	V = 713.97 (8) Å³
Triclinic, P1	Z = 2
a = 7.9700 (5) Å	Mo Kα radiation
b = 7.9852 (5) Å	µ = 2.89 mm⁻¹
c = 11.3185 (7) Å	T = 296 K
α = 86.536 (1)°	0.58 × 0.34 × 0.32 mm
β = 83.205 (1)°

Data collection top

Bruker SMART APEXII DUO CCD area-detector diffractometer	3270 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	2767 reflections with I > 2σ(I)
T_min = 0.286, T_max = 0.461	R_int = 0.017
10671 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	0 restraints
wR(F²) = 0.069	H-atom parameters constrained
S = 1.05	Δρ_max = 0.36 e Å⁻³
3270 reflections	Δρ_min = −0.52 e Å⁻³
191 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	0.26530 (3)	0.93852 (3)	0.738521 (19)	0.06416 (9)
O1	1.05611 (17)	0.7434 (2)	0.48016 (14)	0.0727 (4)
O2	1.07533 (16)	0.58534 (16)	0.28028 (12)	0.0543 (3)
O3	1.07066 (18)	0.84361 (18)	0.19107 (14)	0.0628 (4)
O4	1.82176 (17)	0.60709 (18)	0.03308 (13)	0.0589 (3)
C1	0.6023 (2)	0.7176 (2)	0.48878 (16)	0.0451 (4)
H1A	0.5962	0.6522	0.4242	0.054*
C2	0.4543 (2)	0.7690 (2)	0.55394 (16)	0.0471 (4)
H2A	0.3495	0.7382	0.5337	0.057*
C3	0.4655 (2)	0.8663 (2)	0.64896 (16)	0.0458 (4)
C4	0.6205 (3)	0.9145 (2)	0.67953 (17)	0.0521 (4)
H4A	0.6261	0.9816	0.7433	0.062*
C5	0.7661 (2)	0.8622 (2)	0.61464 (17)	0.0502 (4)
H5A	0.8705	0.8939	0.6351	0.060*
C6	0.7594 (2)	0.7624 (2)	0.51864 (15)	0.0426 (4)
C7	0.9203 (2)	0.7110 (2)	0.44998 (17)	0.0483 (4)
C8	0.9105 (2)	0.6156 (3)	0.33964 (18)	0.0517 (4)
H8A	0.8535	0.5094	0.3618	0.062*
H8B	0.8449	0.6796	0.2858	0.062*
C9	1.1450 (2)	0.7150 (2)	0.21027 (16)	0.0462 (4)
C10	1.3205 (2)	0.6803 (2)	0.16089 (15)	0.0413 (4)
C11	1.4168 (2)	0.5522 (2)	0.20810 (16)	0.0443 (4)
H11A	1.3686	0.4808	0.2708	0.053*
C12	1.5823 (2)	0.5308 (2)	0.16269 (17)	0.0464 (4)
H12A	1.6453	0.4447	0.1946	0.056*
C13	1.6566 (2)	0.6365 (2)	0.06941 (16)	0.0439 (4)
C14	1.5604 (2)	0.7614 (2)	0.01947 (16)	0.0492 (4)
H14A	1.6077	0.8305	−0.0448	0.059*
C15	1.3943 (2)	0.7820 (2)	0.06586 (16)	0.0487 (4)
H15A	1.3304	0.8663	0.0325	0.058*
C16	1.9073 (3)	0.7168 (3)	−0.0585 (2)	0.0675 (6)
H16A	2.0238	0.6843	−0.0727	0.101*
H16B	1.9003	0.8299	−0.0341	0.101*
H16C	1.8554	0.7100	−0.1304	0.101*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.06137 (14)	0.06633 (15)	0.05890 (14)	0.01421 (10)	0.01096 (9)	0.00724 (9)
O1	0.0370 (7)	0.1133 (13)	0.0702 (10)	−0.0055 (8)	−0.0113 (7)	−0.0132 (9)
O2	0.0440 (7)	0.0500 (7)	0.0654 (8)	0.0035 (5)	0.0050 (6)	0.0008 (6)
O3	0.0581 (8)	0.0542 (8)	0.0725 (9)	0.0160 (6)	0.0025 (7)	0.0021 (7)
O4	0.0462 (7)	0.0601 (8)	0.0664 (9)	0.0025 (6)	0.0045 (6)	0.0077 (7)
C1	0.0393 (8)	0.0515 (10)	0.0449 (9)	−0.0038 (7)	−0.0073 (7)	−0.0007 (7)
C2	0.0381 (8)	0.0516 (10)	0.0510 (10)	−0.0043 (7)	−0.0067 (7)	0.0056 (8)
C3	0.0470 (9)	0.0429 (9)	0.0442 (9)	0.0036 (7)	0.0014 (7)	0.0103 (7)
C4	0.0621 (11)	0.0497 (10)	0.0441 (10)	−0.0045 (8)	−0.0064 (8)	0.0000 (8)
C5	0.0470 (9)	0.0553 (11)	0.0489 (10)	−0.0104 (8)	−0.0114 (8)	0.0032 (8)
C6	0.0388 (8)	0.0468 (9)	0.0416 (9)	−0.0048 (7)	−0.0064 (7)	0.0069 (7)
C7	0.0370 (8)	0.0565 (11)	0.0505 (10)	−0.0035 (7)	−0.0067 (7)	0.0072 (8)
C8	0.0383 (9)	0.0569 (11)	0.0586 (11)	0.0000 (8)	−0.0005 (8)	−0.0037 (9)
C9	0.0481 (9)	0.0445 (9)	0.0462 (9)	0.0032 (7)	−0.0050 (7)	−0.0057 (7)
C10	0.0448 (9)	0.0388 (8)	0.0408 (9)	0.0015 (7)	−0.0050 (7)	−0.0058 (7)
C11	0.0463 (9)	0.0410 (9)	0.0448 (9)	−0.0028 (7)	−0.0049 (7)	0.0036 (7)
C12	0.0464 (9)	0.0416 (9)	0.0510 (10)	0.0008 (7)	−0.0091 (8)	0.0047 (7)
C13	0.0445 (9)	0.0430 (9)	0.0439 (9)	−0.0021 (7)	−0.0025 (7)	−0.0056 (7)
C14	0.0572 (11)	0.0451 (10)	0.0429 (9)	0.0013 (8)	0.0012 (8)	0.0030 (7)
C15	0.0563 (10)	0.0422 (9)	0.0465 (9)	0.0076 (8)	−0.0039 (8)	0.0018 (7)
C16	0.0556 (12)	0.0722 (14)	0.0686 (14)	−0.0042 (10)	0.0125 (10)	0.0063 (11)

Geometric parameters (Å, º) top

Br1—C3	1.8925 (18)	C7—C8	1.511 (3)
O1—C7	1.207 (2)	C8—H8A	0.9700
O2—C9	1.346 (2)	C8—H8B	0.9700
O2—C8	1.429 (2)	C9—C10	1.475 (2)
O3—C9	1.203 (2)	C10—C15	1.384 (3)
O4—C13	1.356 (2)	C10—C11	1.394 (2)
O4—C16	1.428 (2)	C11—C12	1.371 (2)
C1—C2	1.389 (2)	C11—H11A	0.9300
C1—C6	1.389 (2)	C12—C13	1.389 (2)
C1—H1A	0.9300	C12—H12A	0.9300
C2—C3	1.376 (3)	C13—C14	1.387 (3)
C2—H2A	0.9300	C14—C15	1.378 (3)
C3—C4	1.385 (3)	C14—H14A	0.9300
C4—C5	1.374 (3)	C15—H15A	0.9300
C4—H4A	0.9300	C16—H16A	0.9600
C5—C6	1.392 (3)	C16—H16B	0.9600
C5—H5A	0.9300	C16—H16C	0.9600
C6—C7	1.488 (2)

C9—O2—C8	115.26 (14)	H8A—C8—H8B	108.0
C13—O4—C16	118.49 (15)	O3—C9—O2	123.12 (17)
C2—C1—C6	121.02 (17)	O3—C9—C10	124.67 (17)
C2—C1—H1A	119.5	O2—C9—C10	112.21 (14)
C6—C1—H1A	119.5	C15—C10—C11	118.55 (16)
C3—C2—C1	118.78 (16)	C15—C10—C9	118.67 (15)
C3—C2—H2A	120.6	C11—C10—C9	122.75 (16)
C1—C2—H2A	120.6	C12—C11—C10	120.37 (16)
C2—C3—C4	121.30 (17)	C12—C11—H11A	119.8
C2—C3—Br1	119.48 (14)	C10—C11—H11A	119.8
C4—C3—Br1	119.22 (14)	C11—C12—C13	120.61 (16)
C5—C4—C3	119.33 (18)	C11—C12—H12A	119.7
C5—C4—H4A	120.3	C13—C12—H12A	119.7
C3—C4—H4A	120.3	O4—C13—C14	124.61 (16)
C4—C5—C6	120.87 (17)	O4—C13—C12	115.91 (16)
C4—C5—H5A	119.6	C14—C13—C12	119.48 (16)
C6—C5—H5A	119.6	C15—C14—C13	119.44 (17)
C1—C6—C5	118.69 (17)	C15—C14—H14A	120.3
C1—C6—C7	122.38 (16)	C13—C14—H14A	120.3
C5—C6—C7	118.91 (16)	C14—C15—C10	121.49 (17)
O1—C7—C6	121.84 (18)	C14—C15—H15A	119.3
O1—C7—C8	119.99 (17)	C10—C15—H15A	119.3
C6—C7—C8	118.17 (15)	O4—C16—H16A	109.5
O2—C8—C7	111.04 (15)	O4—C16—H16B	109.5
O2—C8—H8A	109.4	H16A—C16—H16B	109.5
C7—C8—H8A	109.4	O4—C16—H16C	109.5
O2—C8—H8B	109.4	H16A—C16—H16C	109.5
C7—C8—H8B	109.4	H16B—C16—H16C	109.5

C6—C1—C2—C3	0.3 (3)	C8—O2—C9—C10	174.72 (15)
C1—C2—C3—C4	0.6 (3)	O3—C9—C10—C15	−15.5 (3)
C1—C2—C3—Br1	179.71 (13)	O2—C9—C10—C15	164.40 (16)
C2—C3—C4—C5	−0.9 (3)	O3—C9—C10—C11	162.56 (18)
Br1—C3—C4—C5	179.99 (14)	O2—C9—C10—C11	−17.5 (2)
C3—C4—C5—C6	0.3 (3)	C15—C10—C11—C12	1.5 (3)
C2—C1—C6—C5	−0.8 (3)	C9—C10—C11—C12	−176.60 (17)
C2—C1—C6—C7	−179.34 (17)	C10—C11—C12—C13	0.2 (3)
C4—C5—C6—C1	0.5 (3)	C16—O4—C13—C14	3.6 (3)
C4—C5—C6—C7	179.10 (17)	C16—O4—C13—C12	−176.97 (18)
C1—C6—C7—O1	−176.21 (19)	C11—C12—C13—O4	178.46 (17)
C5—C6—C7—O1	5.3 (3)	C11—C12—C13—C14	−2.1 (3)
C1—C6—C7—C8	3.8 (3)	O4—C13—C14—C15	−178.44 (17)
C5—C6—C7—C8	−174.72 (17)	C12—C13—C14—C15	2.2 (3)
C9—O2—C8—C7	−80.8 (2)	C13—C14—C15—C10	−0.4 (3)
O1—C7—C8—O2	−3.7 (3)	C11—C10—C15—C14	−1.4 (3)
C6—C7—C8—O2	176.31 (15)	C9—C10—C15—C14	176.76 (17)
C8—O2—C9—O3	−5.3 (3)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···O1ⁱ	0.93	2.48	3.386 (2)	164
C11—H11A···Cg1ⁱⁱ	0.93	2.81	3.6395 (18)	149

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

Experimental details

Crystal data
Chemical formula	C₁₆H₁₃BrO₄
M_r	349.17
Crystal system, space group	Triclinic, P1
Temperature (K)	296
a, b, c (Å)	7.9700 (5), 7.9852 (5), 11.3185 (7)
α, β, γ (°)	86.536 (1), 83.205 (1), 89.633 (1)
V (Å³)	713.97 (8)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.89
Crystal size (mm)	0.58 × 0.34 × 0.32

Data collection
Diffractometer	Bruker SMART APEXII DUO CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.286, 0.461
No. of measured, independent and observed [I > 2σ(I)] reflections	10671, 3270, 2767
R_int	0.017
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.069, 1.05
No. of reflections	3270
No. of parameters	191
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.36, −0.52

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2A···O1ⁱ	0.93	2.48	3.386 (2)	164
C11—H11A···Cg1ⁱⁱ	0.93	2.81	3.6395 (18)	149

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

§Thomson Reuters ResearcherID: C-7581-2009.

Acknowledgements

HKF and WSL thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). WSL also thanks the Malaysian Government and USM for the award of a Research Fellowship. AMI is thankful to the Department of Atomic Energy, Board for Research in Nuclear Sciences, Government of India for a `Young scientist' award. GB thanks the Department of Information Technology, New Delhi, India, for financial support.

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