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Acta Crystallogr Sect E Struct Rep Online. 2010 November 1; 66(Pt 11): o2795.
Published online 2010 October 13. doi:  10.1107/S160053681004016X
PMCID: PMC3009183

(4-Bromo­phen­yl)(3,6-dimeth­oxy-2-naphth­yl)methanone

Abstract

In the title compound, C19H15BrO3, the dihedral angle between the naphthalene ring system and the benzene ring is 62.51 (8)°. The bridging carbonyl C—C(=O)—C plane makes dihedral angles of 47.07 (6)° with the naphthalene ring system and 24.20 (10)° with the benzene ring. A weak inter­molecular C—H(...)O hydrogen bond exists between the H atom of one meth­oxy group and the O atom of the other meth­oxy group in an adjacent mol­ecule. The crystal packing is additionally stabilized by two types of weak inter­molecular inter­actions involving the Br atom, C—H(...)Br and Br(...)O [3.2802 (14) Å].

Related literature

For electrophilic aromatic substitution of naphthalene deriv­atives affording peri-aroylated compounds regioselectively, see: Okamoto & Yonezawa (2009 [triangle]). For the structures of closely related compounds, see: Kato et al. (2010 [triangle]); Muto et al. (2010 [triangle]); Nakaema et al. (2008 [triangle]); Watanabe et al. (2010a [triangle],b [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o2795-scheme1.jpg

Experimental

Crystal data

  • C19H15BrO3
  • M r = 371.22
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o2795-efi1.jpg
  • a = 7.88917 (14) Å
  • b = 21.0182 (4) Å
  • c = 10.06272 (18) Å
  • β = 105.971 (1)°
  • V = 1604.16 (5) Å3
  • Z = 4
  • Cu Kα radiation
  • μ = 3.60 mm−1
  • T = 193 K
  • 0.60 × 0.40 × 0.20 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: numerical (NUMABS; Higashi, 1999 [triangle]) T min = 0.161, T max = 0.533
  • 29541 measured reflections
  • 2934 independent reflections
  • 2767 reflections with I > 2σ(I)
  • R int = 0.044

Refinement

  • R[F 2 > 2σ(F 2)] = 0.032
  • wR(F 2) = 0.086
  • S = 1.12
  • 2934 reflections
  • 210 parameters
  • H-atom parameters constrained
  • Δρmax = 0.43 e Å−3
  • Δρmin = −1.03 e Å−3

Data collection: PROCESS-AUTO (Rigaku, 1998 [triangle]); cell refinement: PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2004 [triangle]); program(s) used to solve structure: SIR2004 (Burla et al., 2005 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053681004016X/vm2049sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053681004016X/vm2049Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors would express their gratitude to Professor Keiichi Noguchi, Instrumentation Analysis Center, Tokyo University of Agriculture & Technology, for technical advice. This work was partially supported by the Sasagawa Scientific Research Grant from the Japan Science Society.

supplementary crystallographic information

Comment

In the course of our study on selective electrophilic aromatic aroylation of 2,7-dimethoxynaphthalene, peri-aroylnaphthalene compounds have proved to be formed regioselectively with the aid of suitable acidic mediator (Okamoto & Yonezawa, 2009). Recently, we reported the structures of 1,8-diaroyl-2,7-dimethoxynaphthalenes, i. e., 1,8-bis(4-methylbenzoyl)-2,7-dimethoxynaphthalene (Muto et al., 2010), bis(4-bromophenyl)(2,7-dimethoxynaphthalene-1,8-diyl)dimethanone (Watanabe et al., 2010a), and 1-aroyl-2,7-dimethoxynaphthalene, i. e., 1-benzoyl-2,7-dimethoxynaphthalene (Kato et al., 2010). The aroyl groups at the 1,8-positions of the naphthalene rings in these compounds are twistedly bonded in a perpendicular manner but the benzene ring moieties of the aroyl groups tilt slightly toward the exo sides of the naphthalene rings. 1-Aroyl homologues also revealed essentially the same non-coplanar structure as observed for 1,8-diaroylated naphthalenes.

Furthermore, we also reported the crystal structure analysis of the corresponding β-isomers of 3-aroyl-2,7-dimethoxynaphthalenes such as 2-(4-chlorobenzoyl)-3,6-dimethoxynaphthalene (Nakaema et al., 2008) and (3,6-dimethoxy-2-naphthyl)(4-fluorophenyl)methanone (Watanabe et al., 2010b). In these 3-aroylated naphthalenes, which are generally regarded to be thermodynamically more stable than the corresponding 1-positioned isomeric molecules, the aroyl groups are shown connected to the naphthalene rings in a moderately twisted fashion. As part of our ongoing study on these homologous molecules, the synthesis and crystal structure of the title compound, a 3-monoaroylnaphthalene bearing a bromo group, is discussed in this article. The title compound was prepared by a direct condensation reaction of 2,7-dimethoxynaphthalene with 4-bromobenzoic acid.

The molecular structure of the title molecule is displayed in Fig. 1. The 4-bromophenyl group is bonded twistedly away from the attached naphthalene ring. The dihedral angle between the best planes of the bromophenyl ring (C12—C17) and the naphthalene ring (C1—C10) is 62.51 (8)°. The bridging carbonyl plane (O3—C6—C11—C12) makes a relatively large dihedral angle of 47.07 (9)° with the naphthalene ring (C1—C10) [C5—C6—C11—O3 torsion angle = 46.0 (2)°], whereas it makes a rather small angle of 24.20 (10)° with 4-bromophenyl ring (C12—C17) [O3—C11—C12—C17 torsion angle = 24.1 (3)°].

In the crystal structure, the molecular packing of the title compound is stabilized mainly by van der Waals interactions. Moreover, there is a C—H···O hydrogen bond between a hydrogen of the 2-methoxy group, which is situated adjacent to the bromophenyl group, and the ethereal oxygen atom of the 7-methoxy group in the neighboring molecule (Table 1, Fig. 2).

The crystal packing is additionally stabilized by two types of weak intermolecular interactions with the bromine atom: Br1···O3i = 3.2802 (14) Å, and Br1···H5ii = 2.98 Å [symmetry operations: (i) x, y, z + 1, (ii) -x, -y, -z] (Fig. 3) .

Experimental

The title compound was prepared by treatment of a mixture of 2,7-dimethoxynaphthalene (1.88 g, 10 mmol) and 4-bromobenzoic acid (2.02 g, 10 mmol) with phosphorus pentoxide–methanesulfonic acid mixture (P2O5–MsOH [1/10 w/w]; 10 mL). After the reaction mixture was stirred at 353 K for 8 hours, the mixture was poured into ice-cooled water and extracted with CHCl3 (10 ml × 3). The combined extracts were washed with 2 M aqueous NaOH followed by washing with brine. The organic layer thus obtained was dried over anhydrous MgSO4. The solvent was removed under reduced pressure to give a cake (yield 3.07 g, 83%). The crude product was purified by flush silica gel chromatography (CHCl3). Colorless platelet single crystals suitable for X-ray diffraction were obtained by crystallization from ethanol and chloroform.

Spectroscopic Data:

1H NMR (300 MHz, CDCl3) δ 3.81 (3H, s), 3.93 (3H, s), 7.03 (1H, dd, 9.0 Hz), 7.09 (1H, d, J = 2.4 Hz), 7.12 (1H, s), 7.56 (2H, d, J = 8.4 Hz), 7.67-7.71 (3H, m), 7.78 (1H, s).

13C NMR (75 MHz, CDCl3) δ 55.32, 55.49, 105.01, 105.42, 117.16, 123.18, 127.32, 127.92, 130.05, 130.25, 131.30, 131.46, 136.96, 137.28, 155.64, 159.45, 194.94.

IR (KBr): 1626, 1585, 1501, 1134 cm-1.

HRMS (m/z): [M + H]+ calcd for C19H16BrO3, 371.0283; found, 371.0298.

Refinement

All H atoms were found in a difference map and were subsequently refined as riding atoms, with C–H = 0.93 (aromatic) and 0.96 (methyl) Å, and with Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
Molecular structure with displacement ellipsoids at 50% probability for non-H atoms.
Fig. 2.
C—H···O interactions (dotted lines) [symmetry code: (i) x+1, y, z+1].
Fig. 3.
Two types of intermolecular weak interactions with bromine atom Br1 (dotted lines).

Crystal data

C19H15BrO3F(000) = 752
Mr = 371.22Dx = 1.537 Mg m3
Monoclinic, P21/cMelting point = 416.9–419.5 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54187 Å
a = 7.88917 (14) ÅCell parameters from 26572 reflections
b = 21.0182 (4) Åθ = 4.2–68.3°
c = 10.06272 (18) ŵ = 3.60 mm1
β = 105.971 (1)°T = 193 K
V = 1604.16 (5) Å3Platelet, colorless
Z = 40.60 × 0.40 × 0.20 mm

Data collection

Rigaku R-AXIS RAPID diffractometer2934 independent reflections
Radiation source: rotating anode2767 reflections with I > 2σ(I)
graphiteRint = 0.044
Detector resolution: 10.00 pixels mm-1θmax = 68.3°, θmin = 4.2°
ω scansh = −9→9
Absorption correction: numerical (NUMABS; Higashi, 1999)k = −25→25
Tmin = 0.161, Tmax = 0.533l = −12→12
29541 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.032Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.086H-atom parameters constrained
S = 1.12w = 1/[σ2(Fo2) + (0.0497P)2 + 0.6344P] where P = (Fo2 + 2Fc2)/3
2934 reflections(Δ/σ)max < 0.001
210 parametersΔρmax = 0.43 e Å3
0 restraintsΔρmin = −1.02 e Å3

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 (Å2)

xyzUiso*/Ueq
Br10.24719 (3)0.056869 (10)0.494126 (19)0.03961 (11)
O1−0.46425 (17)0.28009 (7)−0.69867 (14)0.0406 (3)
O20.20106 (17)0.19970 (6)−0.05734 (13)0.0342 (3)
O30.24997 (19)0.03129 (7)−0.18371 (14)0.0405 (3)
C1−0.3611 (2)0.24042 (10)−0.6033 (2)0.0324 (4)
C2−0.3738 (3)0.17558 (10)−0.6441 (2)0.0384 (4)
H2−0.44850.1636−0.72920.046*
C3−0.2762 (3)0.13090 (10)−0.5582 (2)0.0375 (4)
H3−0.28530.0885−0.58540.045*
C4−0.1608 (2)0.14784 (9)−0.4282 (2)0.0302 (4)
C5−0.0537 (2)0.10319 (9)−0.33881 (19)0.0303 (4)
H5−0.06160.0605−0.36430.036*
C60.0620 (2)0.12056 (9)−0.21526 (18)0.0284 (4)
C70.0759 (2)0.18618 (9)−0.17702 (18)0.0279 (4)
C8−0.0283 (2)0.23056 (9)−0.26096 (19)0.0284 (4)
H8−0.01980.2730−0.23400.034*
C9−0.1488 (2)0.21296 (9)−0.38808 (19)0.0278 (4)
C10−0.2524 (2)0.25890 (10)−0.47798 (19)0.0303 (4)
H10−0.24660.3015−0.45200.036*
C110.1740 (2)0.06982 (9)−0.1299 (2)0.0308 (4)
C120.1884 (2)0.06594 (8)0.02077 (19)0.0291 (4)
C130.0583 (2)0.09052 (9)0.0753 (2)0.0349 (4)
H13−0.04010.11000.01690.042*
C140.0731 (3)0.08652 (9)0.2154 (2)0.0363 (4)
H14−0.01550.10240.25090.044*
C150.2217 (3)0.05857 (8)0.3014 (2)0.0312 (4)
C160.3515 (3)0.03239 (10)0.2499 (2)0.0370 (4)
H160.44930.01270.30870.044*
C170.3339 (3)0.03590 (10)0.1099 (2)0.0358 (4)
H170.42000.01800.07430.043*
C18−0.4465 (3)0.34656 (10)−0.6723 (2)0.0454 (5)
H18A−0.52870.3692−0.74510.055*
H18B−0.32860.3596−0.66830.055*
H18C−0.47040.3558−0.58570.055*
C190.2347 (2)0.26549 (10)−0.0224 (2)0.0348 (4)
H19A0.32940.26890.06090.042*
H19B0.13050.2847−0.00860.042*
H19C0.26670.2869−0.09620.042*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.05907 (18)0.03269 (17)0.02418 (16)0.00179 (8)0.00659 (11)−0.00036 (7)
O10.0367 (7)0.0454 (8)0.0321 (7)0.0022 (6)−0.0032 (6)0.0083 (6)
O20.0389 (7)0.0309 (7)0.0260 (7)0.0006 (5)−0.0024 (5)−0.0014 (5)
O30.0488 (8)0.0407 (8)0.0321 (7)0.0134 (6)0.0113 (6)−0.0007 (6)
C10.0269 (8)0.0411 (11)0.0274 (9)0.0000 (7)0.0044 (7)0.0071 (8)
C20.0370 (9)0.0451 (12)0.0269 (10)−0.0061 (8)−0.0017 (8)0.0000 (8)
C30.0399 (10)0.0365 (11)0.0309 (11)−0.0069 (8)0.0011 (8)−0.0009 (9)
C40.0301 (8)0.0321 (10)0.0278 (9)−0.0050 (7)0.0071 (7)0.0003 (7)
C50.0353 (9)0.0280 (9)0.0272 (9)−0.0032 (7)0.0077 (7)−0.0001 (7)
C60.0310 (8)0.0298 (9)0.0248 (9)0.0001 (7)0.0083 (7)0.0030 (7)
C70.0287 (8)0.0325 (9)0.0216 (8)−0.0019 (7)0.0055 (6)−0.0005 (7)
C80.0308 (8)0.0271 (9)0.0263 (9)−0.0003 (7)0.0066 (7)−0.0001 (7)
C90.0261 (8)0.0320 (10)0.0260 (9)−0.0010 (7)0.0083 (7)0.0028 (7)
C100.0298 (9)0.0326 (10)0.0282 (9)−0.0004 (7)0.0074 (7)0.0036 (7)
C110.0324 (9)0.0292 (9)0.0292 (10)0.0004 (7)0.0060 (7)0.0010 (8)
C120.0331 (9)0.0248 (9)0.0282 (10)0.0013 (7)0.0063 (7)0.0023 (7)
C130.0339 (9)0.0383 (10)0.0311 (10)0.0102 (8)0.0067 (8)0.0084 (8)
C140.0404 (10)0.0361 (10)0.0337 (10)0.0087 (8)0.0123 (8)0.0054 (8)
C150.0427 (10)0.0243 (9)0.0246 (9)−0.0018 (7)0.0059 (8)0.0015 (7)
C160.0371 (9)0.0375 (11)0.0313 (10)0.0092 (8)0.0006 (8)0.0032 (8)
C170.0358 (9)0.0372 (11)0.0335 (10)0.0107 (8)0.0081 (8)0.0030 (9)
C180.0429 (11)0.0452 (12)0.0415 (12)0.0071 (9)0.0004 (9)0.0127 (10)
C190.0362 (9)0.0335 (11)0.0304 (9)−0.0010 (7)0.0019 (8)−0.0052 (8)

Geometric parameters (Å, °)

Br1—C151.8942 (19)C8—H80.9300
O1—C11.359 (2)C9—C101.418 (3)
O1—C181.422 (3)C10—H100.9300
O2—C71.361 (2)C11—C121.491 (3)
O2—C191.433 (2)C12—C131.390 (3)
O3—C111.219 (2)C12—C171.398 (3)
C1—C101.372 (3)C13—C141.384 (3)
C1—C21.419 (3)C13—H130.9300
C2—C31.362 (3)C14—C151.383 (3)
C2—H20.9300C14—H140.9300
C3—C41.419 (3)C15—C161.383 (3)
C3—H30.9300C16—C171.379 (3)
C4—C51.409 (3)C16—H160.9300
C4—C91.423 (3)C17—H170.9300
C5—C61.374 (3)C18—H18A0.9600
C5—H50.9300C18—H18B0.9600
C6—C71.428 (3)C18—H18C0.9600
C6—C111.496 (3)C19—H19A0.9600
C7—C81.370 (3)C19—H19B0.9600
C8—C91.417 (2)C19—H19C0.9600
C1—O1—C18117.51 (15)O3—C11—C6120.23 (18)
C7—O2—C19117.30 (14)C12—C11—C6119.37 (16)
O1—C1—C10125.22 (19)C13—C12—C17118.65 (18)
O1—C1—C2113.82 (17)C13—C12—C11121.55 (16)
C10—C1—C2120.96 (17)C17—C12—C11119.78 (17)
C3—C2—C1119.73 (18)C14—C13—C12121.02 (17)
C3—C2—H2120.1C14—C13—H13119.5
C1—C2—H2120.1C12—C13—H13119.5
C2—C3—C4121.30 (19)C15—C14—C13118.84 (18)
C2—C3—H3119.4C15—C14—H14120.6
C4—C3—H3119.4C13—C14—H14120.6
C5—C4—C3122.78 (18)C14—C15—C16121.49 (18)
C5—C4—C9118.58 (16)C14—C15—Br1118.80 (15)
C3—C4—C9118.61 (17)C16—C15—Br1119.71 (14)
C6—C5—C4122.20 (17)C17—C16—C15119.00 (17)
C6—C5—H5118.9C17—C16—H16120.5
C4—C5—H5118.9C15—C16—H16120.5
C5—C6—C7118.89 (16)C16—C17—C12120.94 (18)
C5—C6—C11118.06 (17)C16—C17—H17119.5
C7—C6—C11122.98 (16)C12—C17—H17119.5
O2—C7—C8124.72 (16)O1—C18—H18A109.5
O2—C7—C6115.05 (15)O1—C18—H18B109.5
C8—C7—C6120.19 (16)H18A—C18—H18B109.5
C7—C8—C9121.22 (17)O1—C18—H18C109.5
C7—C8—H8119.4H18A—C18—H18C109.5
C9—C8—H8119.4H18B—C18—H18C109.5
C8—C9—C10121.58 (18)O2—C19—H19A109.5
C8—C9—C4118.88 (16)O2—C19—H19B109.5
C10—C9—C4119.50 (17)H19A—C19—H19B109.5
C1—C10—C9119.90 (19)O2—C19—H19C109.5
C1—C10—H10120.1H19A—C19—H19C109.5
C9—C10—H10120.1H19B—C19—H19C109.5
O3—C11—C12120.38 (17)
C18—O1—C1—C106.0 (3)C3—C4—C9—C100.4 (3)
C18—O1—C1—C2−173.88 (17)O1—C1—C10—C9−178.98 (17)
O1—C1—C2—C3179.56 (18)C2—C1—C10—C90.9 (3)
C10—C1—C2—C3−0.3 (3)C8—C9—C10—C1176.76 (17)
C1—C2—C3—C4−0.2 (3)C4—C9—C10—C1−0.9 (2)
C2—C3—C4—C5−177.87 (19)C5—C6—C11—O346.0 (3)
C2—C3—C4—C90.2 (3)C7—C6—C11—O3−131.1 (2)
C3—C4—C5—C6177.68 (18)C5—C6—C11—C12−132.63 (18)
C9—C4—C5—C6−0.3 (3)C7—C6—C11—C1250.3 (2)
C4—C5—C6—C7−0.9 (3)O3—C11—C12—C13−154.64 (19)
C4—C5—C6—C11−178.08 (17)C6—C11—C12—C1324.0 (3)
C19—O2—C7—C8−4.8 (2)O3—C11—C12—C1724.1 (3)
C19—O2—C7—C6172.93 (15)C6—C11—C12—C17−157.30 (19)
C5—C6—C7—O2−176.14 (16)C17—C12—C13—C141.1 (3)
C11—C6—C7—O20.9 (2)C11—C12—C13—C14179.87 (18)
C5—C6—C7—C81.7 (3)C12—C13—C14—C151.2 (3)
C11—C6—C7—C8178.79 (16)C13—C14—C15—C16−2.7 (3)
O2—C7—C8—C9176.31 (16)C13—C14—C15—Br1176.93 (15)
C6—C7—C8—C9−1.4 (3)C14—C15—C16—C171.8 (3)
C7—C8—C9—C10−177.62 (16)Br1—C15—C16—C17−177.86 (15)
C7—C8—C9—C40.1 (3)C15—C16—C17—C120.7 (3)
C5—C4—C9—C80.8 (3)C13—C12—C17—C16−2.1 (3)
C3—C4—C9—C8−177.36 (17)C11—C12—C17—C16179.15 (19)
C5—C4—C9—C10178.52 (16)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C19—H19A···O1i0.962.533.477 (2)170
C5—H5···Brii0.932.983.8441 (18)155

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: VM2049).

References

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  • Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII Report ORNL-6895. Oak Ridge National Laboratory. Tennessee, USA.
  • Higashi, T. (1999). NUMABS Rigaku Corporation, Tokyo, Japan.
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