9-n-Butyl-9,9′-bi[9H-fluorene]

Shu-Qiang Yu; Bin-Bin Hu; Ping Lu

doi:10.1107/S1600536808001517

. 2008 Jan 23;64(Pt 2):o490. doi: 10.1107/S1600536808001517

9-n-Butyl-9,9′-bi[9H-fluorene]

Shu-Qiang Yu ^a, Bin-Bin Hu ^a, Ping Lu ^a,^*

PMCID: PMC2960402 PMID: 21201513

Abstract

In the title compound, C₃₀H₂₆, the dihedral angle between the two fluorene ring systems is 61.75 (4)°.

Related literature

For general background, see: Muller et al. (2003 ▶); Murahashi & Moritani (1967 ▶).

Experimental

Crystal data

C₃₀H₂₆
M _r = 386.51
Monoclinic,
a = 27.164 (5) Å
b = 8.6369 (17) Å
c = 19.232 (4) Å
β = 104.28 (3)°
V = 4372.7 (15) Å³
Z = 8
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 298 (2) K
0.46 × 0.38 × 0.35 mm

Data collection

Bruker SMART 1000 CCD area-detector diffractometer
Absorption correction: none
20365 measured reflections
4970 independent reflections
2859 reflections with I > 2σ(I)
R _int = 0.031

Refinement

R[F ² > 2σ(F ²)] = 0.039
wR(F ²) = 0.122
S = 1.06
4970 reflections
273 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); 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 publCIF (Westrip, 2008 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808001517/xu2394sup1.cif

e-64-0o490-sup1.cif^{(23.5KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808001517/xu2394Isup2.hkl

e-64-0o490-Isup2.hkl^{(243.5KB, hkl)}

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

Acknowledgments

The authors thank the National Natural Science Foundation of China (20674070) and the Natural Science Foundation of Zhejiang Province (R404109).

supplementary crystallographic information

Comment

Fluorene derivatives, including polyfluorenes and oligofluorenes, remain a subject of intense investigation in recent years because they are very promising candidates for blue light-emitting materials in organic light-emitting devices (Muller et al., 2003). The title compound, 9-n-butyl-9,9'-bi(9H-fluorene)(hereinafter abbreviated to bbf), is one of bifluorene derivatives (Murahashi & Moritani, 1967).

The asymmetric unit of the title compound contains only one bbf molecule (Fig. 1). Two fluorene rings are linked together through their 9-position carbon atoms (C1 and C14). The dihedral angle between the two fluorene rings is 61.75 (4)°. The centroid to centroid distance between stacked fluorene rings is ca 5.92 Å, which is very long and prevents π-π stacking (Fig. 2). All bond lengths and angles are normal.

Experimental

All chemicals were of reagent grade quality obtained from commercial sources and used as received, unless stated otherwise. n-Butylithium (8 ml, 2.5 M, 20 mmol) was added to fluorene (1.66 g, 10 mmol) in 40 ml dry tetrahydrofuran under nitrogen at -78 °C. Subsequently, BF₃Et₂O (0.21 g, 2 mmol) was added. Kept it for 1 h, and warmed it to room temperature and stirred it overnight. After reaction completion, solvent was evaporated under reduced pressure. The crude products were purified by column chromatography (silica gel) using n-hexane/dichloromethane as eluent. The title compound was obtained as white solid in 30% yield. Colorless single crystals were grown from slow evaporation of a saturated CH₂Cl₂ solution of the compound.