3,6-Dibromo­phenanthrene

Ruri Yokota; Chitoshi Kitamura; Takeshi Kawase

doi:10.1107/S1600536812041621

. 2012 Oct 10;68(Pt 11):o3100. doi: 10.1107/S1600536812041621

3,6-Dibromophenanthrene

Ruri Yokota ^a, Chitoshi Kitamura ^a,^*, Takeshi Kawase ^a

PMCID: PMC3515201 PMID: 23284428

Abstract

The phenanthrene ring in the title compound, C₁₄H₈Br₂, is approximately planar [maximum deviation = 0.039 (3) Å]. In contrast, the two bromo atoms are displaced slightly from the phenanthrene plane [maximum deviation = 0.1637 (3) Å]. In the crystal, the molecules adopt a herringbone-like arrangement and form face-to-face slipped π–π stacking interactions along the b axis, with an interplanar distance of 3.544 (3) Å and slippage of 1.81 Å. The crystal studied was a racemic twin with a minor twin fraction of 0.390 (10).

Related literature

For the synthesis of the title compound using the improved photocyclization of 4,4′-dibromo-trans-stilbene, see: Talele et al. (2009 ▶). For the original synthesis and applications of the title compound, see: Nakamura et al. (1996 ▶).

Experimental

Crystal data

C₁₄H₈Br₂
M _r = 336.02
Monoclinic,
a = 6.8697 (5) Å
b = 3.9809 (2) Å
c = 20.5002 (11) Å
β = 93.813 (2)°
V = 559.39 (6) Å³
Z = 2
Mo Kα radiation
μ = 7.21 mm⁻¹
T = 223 K
0.62 × 0.08 × 0.03 mm

Data collection

Rigaku R-AXIS RAPID diffractometer
Absorption correction: numerical (NUMABS; Higashi, 1999 ▶) T _min = 0.196, T _max = 0.793
5372 measured reflections
2267 independent reflections
2084 reflections with I > 2σ(I)
R _int = 0.022

Refinement

R[F ² > 2σ(F ²)] = 0.018
wR(F ²) = 0.037
S = 1.00
2267 reflections
146 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.38 e Å⁻³
Δρ_min = −0.46 e Å⁻³
Absolute structure: Flack (1983 ▶), 831 Friedel pairs
Flack parameter: 0.390 (10)

Data collection: RAPID-AUTO (Rigaku, 1999 ▶); cell refinement: PROCESS-AUTO (Rigaku, 1998 ▶); data reduction: PROCESS-AUTO; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Click here for additional data file.^{(15.3KB, cif)}

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536812041621/qk2043sup1.cif

e-68-o3100-sup1.cif^{(15.3KB, cif)}

Click here for additional data file.^{(111.4KB, hkl)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812041621/qk2043Isup2.hkl

e-68-o3100-Isup2.hkl^{(111.4KB, hkl)}

Click here for additional data file.^{(4KB, cml)}

Supplementary material file. DOI: 10.1107/S1600536812041621/qk2043Isup3.cml

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

Acknowledgments

This work was supported by Grants-in-Aid for Scientific Research from the JSPS and MEXT.

supplementary crystallographic information

Comment

Phenanthrene is a polycylic aromatic hydrocarbon (PAH) as well as a potential building block for higher-order π-extended PAHs. The title compound, 3,6-dibromophenanthrene, was first prepared by Nakamura et al. (1996). The bromo functional group on the aromatic ring is a suitable substrate for a variety of cross-coupling reaction. Recently, the improved synthesis was reported by Talele et al. (2009). However, the X-ray structure was not reported to date. We report herein the crystal structure of the title compound, (I).

The molecular structure of (I) is shown in Fig. 1. The crystal was a racemic twin with a minor twin fraction of 0.390 (10). The molecule is approximately planar except for Br1 and Br2 [the maximum deviation is 0.1637 (3) Å for Br2]. The bonds lengths and angles are in good agreement with the standard values. As shown in Fig. 2, the crystal structure is characterized by a combination of a columnar stacking and a herrinbone-like arrangement. Along the b axis, there are two columns per unit cell in which the molecules form face-to-face slipped π-stacks with an interplanar distance of 3.543 Å. The interplanar tilt angle between the phenanthrene rings in two adjacent columns is 54.21°.

Experimental

The title compound was prepared from 4,4'-dibromo-trans-stilbene according to the literature procedure of Talele et al. (2009). The title compound was dissolved in hot hexane. After cooling of the solution to room temperature, single crystals suitable for X-ray analysis were obtained.