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Acta Crystallogr Sect E Struct Rep Online. 2010 February 1; 66(Pt 2): o403.
Published online 2010 January 20. doi:  10.1107/S1600536810001819
PMCID: PMC2979875

Bis(4-bromo­benzo­yl)(2,7-dimethoxy­naphthalene-1,8-di­yl)dimethanone

Abstract

In the title compound, C26H18Br2O4, the two 4-bromo­benzoyl groups at the 1- and 8-positions of the naphthalene ring system are anti to each other. The dihedral angle between the two benzene rings is 50.92 (14)°. The dihedral angles between the two benzene rings and the naphthalene ring system are 70.18 (11) and 74.98 (12)°. A weak inter­molecular C—H(...)O hydrogen bond exists between the methyl group and the carbonyl O atom.

Related literature

For general background to the regioselective formation of peri-aroylnaphthalene compounds, see: Okamoto & Yonezawa (2009 [triangle]). For related structures, see: Mitsui et al. (2009 [triangle]); Nakaema et al. (2007 [triangle], 2008 [triangle]); Watanabe et al. (2010 [triangle]).

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Object name is e-66-0o403-scheme1.jpg

Experimental

Crystal data

  • C26H18Br2O4
  • M r = 554.22
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o403-efi1.jpg
  • a = 7.8748 (5) Å
  • b = 25.7908 (16) Å
  • c = 11.5618 (7) Å
  • β = 100.982 (4)°
  • V = 2305.2 (2) Å3
  • Z = 4
  • Cu Kα radiation
  • μ = 4.71 mm−1
  • T = 296 K
  • 0.60 × 0.30 × 0.20 mm

Data collection

  • Rigaku R-AXIS RAPID diffractometer
  • Absorption correction: numerical (NUMABS; Higashi, 1999 [triangle]) T min = 0.164, T max = 0.452
  • 42468 measured reflections
  • 4220 independent reflections
  • 3825 reflections with I > 2σ(I)
  • R int = 0.064

Refinement

  • R[F 2 > 2σ(F 2)] = 0.038
  • wR(F 2) = 0.103
  • S = 1.05
  • 4220 reflections
  • 292 parameters
  • H-atom parameters constrained
  • Δρmax = 0.73 e Å−3
  • Δρmin = −0.66 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/S1600536810001819/is2516sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810001819/is2516Isup2.hkl

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

Acknowledgments

The authors would express their gratitude to Professor Keiichi Noguchi for his technical advice. This work was partially supported by the Iketani Science and Technology Foundation, Tokyo, Japan.

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). The aroyl groups at 1,8-positions of the naphthalene rings in these compounds are oriented in opposite fashion and are found to be non-coplanar resulting in partial disruption in π-conjugation systems. Recently, we have reported the X-ray crystal structures of 1,8-bis(4-chlorobenzoyl)-2,7-dimethoxynaphthalene (Nakaema et al., 2007), 1,8-dibenzoyl-2,7-dimethoxynaphthalene (Nakaema et al., 2008) and (2,7-dimethoxynaphthalene-1,8-diyl)-bis(4-fluorobenzoyl)dimethanone (Watanabe et al., 2010). As a part of the course of our continuous study on the molecular structures of this kind of homologous molecules, the X-ray crystal structure of title compound, peri-aroylnaphthalene bearing bromo groups, is discussed in this report.

The molecular structure of the title molecule is displayed in Fig. 1. The two 4-bromobenzoyl groups are situated in anti orientation. Furthermore, these 4-bromobenzoyl groups are twisted away from the attached naphthalene ring. The interplanar angle between the best planes of two benzene rings is 50.92 (14)°. On the other hand, the two interplanar angles between the best planes of the peri-bromophenyl rings and the naphthalene ring are 70.18 (11) and 74.98 (12)°. The torsion angles between the carbonyl groups and the naphthalene ring are relatively large [C10—C1—C11—O3 = -53.3 (3)° and C10—C9—C18—O1 = -47.3 (3)°] and those between 4-bromophenyl groups and carbonyl groups are rather small [O3—C11—C12—C17 = -16.8 (4)° and O1—C18—C19—C20 = -20.0 (4)°]. The crystal packing is stabilized by weak C—H···O hydrogen bonds (Table 1).

Experimental

The title compound was prepared by electrophilic aromatic diaroylation reaction of 2,7-dimethoxynaphthalene with 4-bromobenzoic acid. Colorless single crystals suitable for X-ray diffraction were obtained by recrystallization from ethanol.

Spectroscopic Data: 1H NMR (300 MHz, CDCl3): δ 3.69 (6H, s), 7.19 (2H, d, J = 9.0 Hz), 7.47 (4H, d, J = 8.4 Hz), 7.54 (4H, d, J = 8.4 Hz), 7.95 (2H, d, J = 9.0 Hz); 13C NMR (75.0 MHz, CDCl3): δ 56.3, 111.1, 120.6, 125.5, 127.9, 123.0, 130.6, 131.4, 132.5, 137.5, 156.5, 196.2; IR (KBr cm-1): 1660, 1269; m.p. = 250 °C.

Refinement

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

Figures

Fig. 1.
The molecular structure of the title compound with displacement ellipsoids at 50% probability for non-H atoms.

Crystal data

C26H18Br2O4F(000) = 1104
Mr = 554.22Dx = 1.597 Mg m3
Monoclinic, P21/cMelting point: 523 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54187 Å
a = 7.8748 (5) ÅCell parameters from 40803 reflections
b = 25.7908 (16) Åθ = 3.4–68.2°
c = 11.5618 (7) ŵ = 4.71 mm1
β = 100.982 (4)°T = 296 K
V = 2305.2 (2) Å3Platelet, colorless
Z = 40.60 × 0.30 × 0.20 mm

Data collection

Rigaku R-AXIS RAPID diffractometer4220 independent reflections
Radiation source: rotating anode3825 reflections with I > 2σ(I)
graphiteRint = 0.064
Detector resolution: 10.00 pixels mm-1θmax = 68.2°, θmin = 3.4°
ω scansh = −9→9
Absorption correction: numerical (NUMABS; Higashi, 1999)k = −31→31
Tmin = 0.164, Tmax = 0.452l = −13→13
42468 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.103w = 1/[σ2(Fo2) + (0.0451P)2 + 1.8271P] where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
4220 reflectionsΔρmax = 0.73 e Å3
292 parametersΔρmin = −0.66 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.00195 (13)

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
Br10.72128 (5)0.437493 (13)0.07373 (3)0.07441 (16)
Br21.22096 (6)0.071146 (15)0.46717 (4)0.08957 (19)
O10.7621 (2)0.18244 (7)−0.02615 (16)0.0540 (4)
O20.7527 (3)0.04184 (9)−0.0577 (2)0.0725 (6)
O30.5203 (3)0.18565 (8)0.17194 (16)0.0626 (5)
O40.1847 (3)0.25609 (10)−0.0098 (2)0.0817 (7)
C10.3713 (3)0.18756 (10)−0.0245 (2)0.0478 (6)
C20.2137 (4)0.21142 (12)−0.0655 (3)0.0591 (7)
C30.0891 (4)0.18868 (15)−0.1549 (3)0.0706 (8)
H3−0.01310.2061−0.18520.085*
C40.1205 (4)0.14116 (15)−0.1958 (3)0.0711 (9)
H40.03600.1256−0.25230.085*
C50.2764 (4)0.11461 (12)−0.1558 (2)0.0585 (7)
C60.3060 (5)0.06490 (13)−0.1987 (3)0.0696 (9)
H60.21840.0492−0.25260.083*
C70.4558 (5)0.03943 (12)−0.1646 (3)0.0661 (8)
H70.46940.0062−0.19270.079*
C80.5925 (4)0.06332 (11)−0.0859 (2)0.0558 (7)
C90.5715 (3)0.11220 (10)−0.0403 (2)0.0460 (6)
C100.4095 (3)0.13854 (10)−0.0715 (2)0.0487 (6)
C110.4846 (3)0.21101 (10)0.0821 (2)0.0483 (6)
C120.5453 (3)0.26560 (10)0.0768 (2)0.0446 (5)
C130.5458 (3)0.29065 (10)−0.0294 (2)0.0474 (6)
H130.50730.2731−0.09990.057*
C140.6028 (4)0.34120 (10)−0.0320 (2)0.0508 (6)
H140.60580.3576−0.10320.061*
C150.6551 (3)0.36681 (10)0.0736 (2)0.0498 (6)
C160.6569 (4)0.34286 (11)0.1802 (2)0.0561 (7)
H160.69370.36070.25040.067*
C170.6036 (4)0.29216 (11)0.1813 (2)0.0543 (6)
H170.60660.27540.25300.065*
C180.7312 (3)0.14120 (10)0.0171 (2)0.0450 (5)
C190.8499 (3)0.12117 (9)0.1232 (2)0.0463 (6)
C201.0174 (4)0.14010 (12)0.1497 (3)0.0615 (7)
H201.05490.16360.09900.074*
C211.1292 (4)0.12445 (13)0.2506 (3)0.0680 (8)
H211.24200.13690.26770.082*
C221.0712 (4)0.09027 (10)0.3249 (2)0.0560 (7)
C230.9078 (4)0.07017 (11)0.3003 (3)0.0595 (7)
H230.87180.04640.35110.071*
C240.7965 (4)0.08571 (11)0.1986 (2)0.0559 (7)
H240.68510.07220.18090.067*
C250.0244 (4)0.28190 (14)−0.0380 (4)0.0872 (12)
H25A0.03020.31390.00500.105*
H25B−0.06470.2604−0.01730.105*
H25C−0.00160.2890−0.12100.105*
C260.7792 (6)−0.00847 (14)−0.1026 (4)0.0892 (12)
H26A0.8985−0.0181−0.07860.107*
H26B0.7494−0.0080−0.18700.107*
H26C0.7076−0.0332−0.07220.107*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Br10.0966 (3)0.0548 (2)0.0726 (2)−0.01775 (16)0.01798 (19)−0.00874 (14)
Br20.0988 (3)0.0691 (3)0.0839 (3)0.00526 (19)−0.0253 (2)0.01543 (18)
O10.0562 (11)0.0522 (11)0.0536 (10)−0.0098 (8)0.0102 (8)0.0071 (8)
O20.0782 (15)0.0593 (12)0.0778 (14)0.0047 (11)0.0087 (11)−0.0213 (11)
O30.0877 (15)0.0586 (11)0.0417 (10)−0.0066 (10)0.0131 (9)0.0028 (8)
O40.0507 (12)0.0856 (16)0.1094 (19)0.0056 (11)0.0163 (12)−0.0257 (14)
C10.0456 (14)0.0549 (15)0.0445 (13)−0.0100 (11)0.0128 (10)−0.0023 (11)
C20.0474 (15)0.0674 (18)0.0639 (17)−0.0093 (13)0.0136 (13)−0.0031 (14)
C30.0493 (17)0.089 (2)0.070 (2)−0.0042 (15)0.0039 (14)0.0004 (17)
C40.0564 (18)0.089 (2)0.0636 (18)−0.0159 (16)−0.0006 (14)−0.0074 (17)
C50.0576 (16)0.0679 (18)0.0488 (14)−0.0176 (14)0.0072 (12)−0.0061 (13)
C60.074 (2)0.070 (2)0.0597 (18)−0.0244 (16)0.0006 (15)−0.0150 (14)
C70.083 (2)0.0525 (16)0.0622 (18)−0.0176 (15)0.0118 (16)−0.0150 (14)
C80.0675 (18)0.0517 (15)0.0490 (15)−0.0093 (13)0.0129 (13)−0.0054 (11)
C90.0539 (14)0.0482 (13)0.0366 (12)−0.0111 (11)0.0102 (10)−0.0019 (10)
C100.0540 (15)0.0542 (14)0.0391 (12)−0.0152 (12)0.0121 (11)−0.0001 (10)
C110.0513 (14)0.0553 (15)0.0407 (13)−0.0019 (11)0.0150 (11)−0.0037 (11)
C120.0443 (13)0.0524 (14)0.0378 (12)−0.0012 (10)0.0096 (10)−0.0031 (10)
C130.0558 (15)0.0502 (14)0.0361 (12)0.0004 (11)0.0082 (10)−0.0064 (10)
C140.0608 (16)0.0518 (14)0.0406 (13)0.0014 (12)0.0116 (11)0.0028 (11)
C150.0507 (14)0.0465 (13)0.0526 (14)−0.0023 (11)0.0104 (11)−0.0047 (11)
C160.0661 (17)0.0624 (17)0.0396 (13)−0.0110 (13)0.0093 (12)−0.0113 (12)
C170.0645 (17)0.0627 (16)0.0359 (12)−0.0072 (13)0.0103 (11)−0.0021 (11)
C180.0501 (14)0.0464 (13)0.0406 (12)−0.0057 (11)0.0137 (10)−0.0023 (10)
C190.0521 (14)0.0437 (13)0.0439 (13)−0.0056 (10)0.0113 (11)−0.0026 (10)
C200.0567 (17)0.0619 (17)0.0647 (17)−0.0107 (13)0.0087 (13)0.0141 (14)
C210.0543 (17)0.0665 (19)0.078 (2)−0.0080 (14)−0.0012 (15)0.0080 (15)
C220.0661 (17)0.0436 (14)0.0532 (15)0.0060 (12)−0.0016 (13)−0.0005 (11)
C230.078 (2)0.0497 (15)0.0505 (15)−0.0066 (13)0.0105 (14)0.0055 (12)
C240.0618 (17)0.0538 (15)0.0515 (15)−0.0148 (13)0.0091 (12)0.0022 (12)
C250.065 (2)0.0543 (18)0.142 (4)0.0001 (15)0.021 (2)0.015 (2)
C260.107 (3)0.068 (2)0.089 (3)0.018 (2)0.009 (2)−0.0228 (19)

Geometric parameters (Å, °)

Br1—C151.896 (3)C12—C171.389 (3)
Br2—C221.897 (3)C13—C141.381 (4)
O1—C181.219 (3)C13—H130.9300
O2—C81.359 (4)C14—C151.381 (4)
O2—C261.427 (4)C14—H140.9300
O3—C111.214 (3)C15—C161.376 (4)
O4—C21.361 (4)C16—C171.374 (4)
O4—C251.409 (4)C16—H160.9300
C1—C21.386 (4)C17—H170.9300
C1—C101.430 (4)C18—C191.487 (4)
C1—C111.505 (4)C19—C201.384 (4)
C2—C31.409 (4)C19—C241.383 (4)
C3—C41.354 (5)C20—C211.381 (4)
C3—H30.9300C20—H200.9300
C4—C51.405 (5)C21—C221.369 (4)
C4—H40.9300C21—H210.9300
C5—C61.410 (4)C22—C231.366 (4)
C5—C101.429 (4)C23—C241.385 (4)
C6—C71.342 (5)C23—H230.9300
C6—H60.9300C24—H240.9300
C7—C81.412 (4)C25—H25A0.9600
C7—H70.9300C25—H25B0.9600
C8—C91.389 (4)C25—H25C0.9600
C9—C101.429 (4)C26—H26A0.9600
C9—C181.504 (3)C26—H26B0.9600
C11—C121.492 (4)C26—H26C0.9600
C12—C131.389 (3)
C8—O2—C26118.4 (3)C13—C14—H14120.8
C2—O4—C25120.9 (3)C16—C15—C14121.9 (2)
C2—C1—C10120.1 (2)C16—C15—Br1118.37 (19)
C2—C1—C11117.0 (2)C14—C15—Br1119.8 (2)
C10—C1—C11122.1 (2)C17—C16—C15119.0 (2)
O4—C2—C1115.7 (3)C17—C16—H16120.5
O4—C2—C3122.9 (3)C15—C16—H16120.5
C1—C2—C3121.3 (3)C16—C17—C12120.8 (2)
C4—C3—C2119.0 (3)C16—C17—H17119.6
C4—C3—H3120.5C12—C17—H17119.6
C2—C3—H3120.5O1—C18—C19119.9 (2)
C3—C4—C5122.1 (3)O1—C18—C9117.9 (2)
C3—C4—H4118.9C19—C18—C9122.2 (2)
C5—C4—H4118.9C20—C19—C24119.0 (3)
C4—C5—C6121.3 (3)C20—C19—C18118.9 (2)
C4—C5—C10119.7 (3)C24—C19—C18122.1 (2)
C6—C5—C10118.9 (3)C21—C20—C19120.7 (3)
C7—C6—C5122.5 (3)C21—C20—H20119.6
C7—C6—H6118.8C19—C20—H20119.6
C5—C6—H6118.8C22—C21—C20118.9 (3)
C6—C7—C8119.7 (3)C22—C21—H21120.6
C6—C7—H7120.2C20—C21—H21120.6
C8—C7—H7120.2C23—C22—C21121.8 (3)
O2—C8—C9116.8 (2)C23—C22—Br2119.2 (2)
O2—C8—C7122.4 (3)C21—C22—Br2119.0 (2)
C9—C8—C7120.6 (3)C22—C23—C24119.1 (3)
C8—C9—C10120.1 (2)C22—C23—H23120.5
C8—C9—C18117.9 (2)C24—C23—H23120.5
C10—C9—C18120.4 (2)C19—C24—C23120.5 (3)
C5—C10—C9118.1 (2)C19—C24—H24119.8
C5—C10—C1117.4 (3)C23—C24—H24119.8
C9—C10—C1124.5 (2)O4—C25—H25A109.5
O3—C11—C12121.3 (2)O4—C25—H25B109.5
O3—C11—C1119.3 (2)H25A—C25—H25B109.5
C12—C11—C1119.3 (2)O4—C25—H25C109.5
C13—C12—C17118.9 (2)H25A—C25—H25C109.5
C13—C12—C11122.1 (2)H25B—C25—H25C109.5
C17—C12—C11119.0 (2)O2—C26—H26A109.5
C14—C13—C12120.9 (2)O2—C26—H26B109.5
C14—C13—H13119.5H26A—C26—H26B109.5
C12—C13—H13119.5O2—C26—H26C109.5
C15—C14—C13118.4 (2)H26A—C26—H26C109.5
C15—C14—H14120.8H26B—C26—H26C109.5
C25—O4—C2—C1−175.5 (3)C10—C1—C11—O3−53.2 (4)
C25—O4—C2—C31.0 (5)C2—C1—C11—C12−60.4 (3)
C10—C1—C2—O4175.6 (2)C10—C1—C11—C12129.1 (3)
C11—C1—C2—O44.9 (4)O3—C11—C12—C13163.0 (3)
C10—C1—C2—C3−1.0 (4)C1—C11—C12—C13−19.4 (4)
C11—C1—C2—C3−171.6 (3)O3—C11—C12—C17−16.8 (4)
O4—C2—C3—C4−172.1 (3)C1—C11—C12—C17160.8 (2)
C1—C2—C3—C44.1 (5)C17—C12—C13—C14−0.2 (4)
C2—C3—C4—C5−2.7 (5)C11—C12—C13—C14−179.9 (2)
C3—C4—C5—C6179.4 (3)C12—C13—C14—C15−1.7 (4)
C3—C4—C5—C10−1.8 (5)C13—C14—C15—C162.1 (4)
C4—C5—C6—C7177.9 (3)C13—C14—C15—Br1−176.3 (2)
C10—C5—C6—C7−1.0 (5)C14—C15—C16—C17−0.6 (4)
C5—C6—C7—C8−2.2 (5)Br1—C15—C16—C17177.8 (2)
C26—O2—C8—C9179.7 (3)C15—C16—C17—C12−1.3 (4)
C26—O2—C8—C7−4.8 (5)C13—C12—C17—C161.7 (4)
C6—C7—C8—O2−173.1 (3)C11—C12—C17—C16−178.6 (3)
C6—C7—C8—C92.2 (5)C8—C9—C18—O1118.2 (3)
O2—C8—C9—C10176.5 (2)C10—C9—C18—O1−47.3 (3)
C7—C8—C9—C100.9 (4)C8—C9—C18—C19−61.8 (3)
O2—C8—C9—C1810.9 (4)C10—C9—C18—C19132.6 (3)
C7—C8—C9—C18−164.7 (3)O1—C18—C19—C20−20.0 (4)
C4—C5—C10—C9−174.9 (3)C9—C18—C19—C20160.0 (3)
C6—C5—C10—C94.0 (4)O1—C18—C19—C24157.6 (3)
C4—C5—C10—C14.8 (4)C9—C18—C19—C24−22.4 (4)
C6—C5—C10—C1−176.3 (3)C24—C19—C20—C21−0.8 (5)
C8—C9—C10—C5−4.0 (4)C18—C19—C20—C21176.8 (3)
C18—C9—C10—C5161.3 (2)C19—C20—C21—C22−0.7 (5)
C8—C9—C10—C1176.4 (2)C20—C21—C22—C231.9 (5)
C18—C9—C10—C1−18.3 (4)C20—C21—C22—Br2−177.1 (3)
C2—C1—C10—C5−3.4 (4)C21—C22—C23—C24−1.5 (5)
C11—C1—C10—C5166.7 (2)Br2—C22—C23—C24177.5 (2)
C2—C1—C10—C9176.2 (2)C20—C19—C24—C231.3 (4)
C11—C1—C10—C9−13.7 (4)C18—C19—C24—C23−176.3 (3)
C2—C1—C11—O3117.2 (3)C22—C23—C24—C19−0.2 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C25—H25B···O1i0.962.423.313 (4)155

Symmetry codes: (i) x−1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: IS2516).

References

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