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Acta Cryst. (2008). E64, o996    [ doi:10.1107/S1600536808012117 ]

9-Chloromethyl-9-[(9H-fluoren-9-yl)methyl]-9H-fluorene

Q. Shen, S.-Q. Yu, B.-B. Hu and P. Lu

Abstract top

In the title compound, C28H21Cl, the dihedral angle between the two fluorene ring systems is 71.97 (4)°. There is an intramolecular C-H...Cl hydrogen bond. In the crystal structure, the centroid-to-centroid distance between stacked fluorene ring systems is ca 4.22 Å, which indicates that there are no [pi]-[pi] stacking interactions between them.

Comment top

Fluorene derivatives, have attracted much attention due to their potential utilities in organic lightemitting devices (Muller et al., 2003), organic phototransistors (Saragi et al., 2004), nonlinear optics (Kim et al., 1998) and photochromic materials (Chun et al., 2003). The title compound (hereinafter abbreviated to fmcf) is one of fluorene derivatives.

The asymmetric unit of the title compound contains one fmcf molecule (Fig. 1). The chloromethyl group is attached on the C-9 position of one fluorene ring. Two fluorene rings are linked together through a methylene carbon atom, and the dihedral angle between the two fluorene rings is 71.97 (4)°. There is intramolecular C–H···Cl hydrogen bond with distance of 3.075 (2) Å (Table 1), while the intermolecular C–H···Cl contacts are of 3.573 (2) Å, which is not viewed as C–H···Cl hydrogen bond. The centroid to centroid distance between stacked fluorene rings is ca. 4.22 Å, which is very long and prevents π···π stacking (Fig. 2). All bond lengths and angles are normal.

Related literature top

For general background, see: Chun et al. (2003); Kim et al. (1998); Muller et al. (2003); Saragi et al. (2004).

Experimental top

All chemicals were of analytic grade quality obtained from commercial sources and used as received, unless stated otherwise. To a solution of fluorene (1.66 g, 10 mmol) in dry THF (40 ml) was added a hexane solution of n-butylithium (4 ml, 2.5 M, 10 mmol) under nitrogen at -78 °C, the mixture was stirred for 1 h. A solution of PCl3 (2 mmol) in THF (10 ml) was then added. After stirring for another 1 h, the mixture was cooling slowly to room temperature, and kept stirring overnight. To the mixture was added dichloromethane (20 ml) and stirred for 1 h. The solvent was evaporated under reduced pressure. The crude products were purified by columnchromatography (silica gel) using n-hexane/dichloromethane as eluent. The title compound was obtained as white solid in 31% yield. Colorless single crystals were grown from a CH2Cl2 solution of the compound.

Refinement top

H atoms were positioned geometrically and treated as riding, with C—H = 0.93 (aromatic), 0.97 (methylene) and 0.98 Å (methine), and refined in riding mode with Uiso(H) = 1.2Ueq(C).

Computing details top

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

Figures top
[Figure 1] Fig. 1. The molecular structure showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Partial packing view of the title compound. H atoms are omitted for clarity.
9-Chloromethyl-9-[(9H-fluoren-9-yl)methyl]-9H-fluorene top
Crystal data top
C28H21ClF000 = 824
Mr = 392.90Dx = 1.290 Mg m−3
Monoclinic, P21/cMo Kα radiation
λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 12994 reflections
a = 8.4346 (17) Åθ = 3.1–27.4º
b = 26.368 (5) ŵ = 0.20 mm−1
c = 9.1162 (18) ÅT = 298 (2) K
β = 94.08 (3)ºChunk, colorless
V = 2022.3 (7) Å30.35 × 0.29 × 0.22 mm
Z = 4
Data collection top
Bruker SMART 1000 CCD area-detector
diffractometer		2747 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.025
Monochromator: graphiteθmax = 25.3º
T = 298(2) Kθmin = 3.1º
φ and ω scansh = −10→10
Absorption correction: nonek = −31→31
16094 measured reflectionsl = −10→10
3646 independent reflections
Refinement top
Refinement on F2Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: fullH-atom parameters constrained
R[F2 > 2σ(F2)] = 0.040  w = 1/[σ2(Fo2) + (0.0595P)2 + 0.3188P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.133(Δ/σ)max < 0.001
S = 1.08Δρmax = 0.22 e Å−3
3646 reflectionsΔρmin = −0.25 e Å−3
263 parametersExtinction correction: SHELXTL (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.011 (2)
Secondary atom site location: difference Fourier map
Crystal data top
C28H21ClV = 2022.3 (7) Å3
Mr = 392.90Z = 4
Monoclinic, P21/cMo Kα
a = 8.4346 (17) ŵ = 0.20 mm−1
b = 26.368 (5) ÅT = 298 (2) K
c = 9.1162 (18) Å0.35 × 0.29 × 0.22 mm
β = 94.08 (3)º
Data collection top
Bruker SMART 1000 CCD area-detector
diffractometer		3646 independent reflections
Absorption correction: none2747 reflections with I > 2σ(I)
16094 measured reflectionsRint = 0.025
Refinement top
R[F2 > 2σ(F2)] = 0.040263 parameters
wR(F2) = 0.133H-atom parameters constrained
S = 1.08Δρmax = 0.22 e Å−3
3646 reflectionsΔρmin = −0.25 e Å−3
Special details top

Experimental. 1HNMR (500 MHz, δ in p.p.m., CDCl3): 2.90 (d, 2H, J = 5.5 Hz), 3.19 (t, 1H,J= 4.5 Hz), 3.86 (s, 2H), 6.62 (d, 2H, J = 7.0 Hz), 7.02 (t, 2H, J= 7.5 Hz), 7.19 (t, 2H, J = 7.5 Hz), 7.39 (t, 2H, J = 7.5 Hz), 7.46 (t, 2H, J = 7.5 Hz), 7.54 (d, 2H,J = 7.5 Hz), 7.67 (d, 2H, J = 7.5 Hz), 7.78 (d, 2H, J= 7.0 Hz); 13C NMR (125 MHz, δ in p.p.m., CDCl3): 40.64, 44.45, 53.35, 55.55, 119.52, 120.75, 125.06, 125.18, 126.86, 126.92, 127.66,128.74, 140.70, 141.48, 146.99, 148.22; MS (EI): calcd for C28H21Cl, 392; found: 392 (M+), 356, 191 (100), 179, 165, 152.

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 F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
xyzUiso*/Ueq
Cl10.14417 (6)0.73515 (2)0.46199 (7)0.0815 (2)
C10.38752 (16)0.68247 (6)0.60052 (19)0.0421 (4)
C20.30669 (16)0.65243 (5)0.72229 (18)0.0407 (4)
C30.16272 (18)0.63563 (7)0.7173 (2)0.0546 (5)
H30.09260.64020.63490.066*
C40.1160 (2)0.60914 (7)0.8475 (3)0.0671 (6)
H40.01210.59710.84340.080*
C50.2094 (2)0.59950 (7)0.9791 (3)0.0651 (5)
H50.16920.58211.05710.078*
C60.3524 (2)0.61602 (7)0.9853 (2)0.0547 (5)
H60.42160.61131.06820.066*
C70.40065 (17)0.64228 (5)0.85735 (18)0.0410 (4)
C80.54497 (17)0.66472 (6)0.83543 (19)0.0427 (4)
C90.6747 (2)0.66400 (7)0.9329 (2)0.0581 (5)
H90.67870.64721.02280.070*
C100.7950 (2)0.69009 (8)0.8846 (3)0.0731 (7)
H100.88990.69130.94300.088*
C110.7859 (2)0.71698 (9)0.7450 (3)0.0778 (7)
H110.87490.73530.72150.093*
C120.6578 (2)0.71744 (7)0.6465 (3)0.0635 (5)
H120.65450.73490.55760.076*
C130.53712 (17)0.69020 (6)0.6907 (2)0.0455 (4)
C140.47723 (18)0.60085 (6)0.46017 (19)0.0461 (4)
H140.50530.59430.56460.055*
C150.38570 (18)0.55633 (6)0.39464 (19)0.0460 (4)
C160.2451 (2)0.54170 (7)0.4245 (2)0.0573 (5)
H160.18670.55920.49090.069*
C170.1854 (2)0.49837 (7)0.3523 (2)0.0637 (5)
H170.08480.48740.37370.076*
C180.2642 (2)0.47010 (7)0.2507 (3)0.0659 (5)
H180.21670.44160.20630.079*
C190.4057 (2)0.48432 (7)0.2191 (2)0.0593 (5)
H190.46280.46680.15160.071*
C200.46626 (18)0.52716 (6)0.29204 (19)0.0473 (4)
C210.61091 (18)0.55048 (7)0.28235 (19)0.0497 (4)
C220.7292 (2)0.53544 (8)0.1985 (2)0.0626 (5)
H220.72110.50700.13830.075*
C230.8541 (2)0.56413 (10)0.2096 (3)0.0737 (6)
H230.93980.55610.15520.088*
C240.8643 (2)0.60722 (9)0.3016 (3)0.0766 (6)
H240.95730.62620.30440.092*
C250.7467 (2)0.62294 (9)0.3868 (2)0.0666 (6)
H250.75610.65150.44660.080*
C260.61912 (18)0.59411 (7)0.37704 (19)0.0501 (4)
C270.40233 (18)0.65354 (6)0.44306 (19)0.0472 (4)
H27A0.29720.65030.39340.057*
H27B0.46610.67410.38160.057*
C280.3207 (2)0.73528 (7)0.5688 (2)0.0576 (5)
H28A0.39830.75490.51930.069*
H28B0.30450.75200.66130.069*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0610 (3)0.0870 (4)0.0956 (5)0.0332 (3)−0.0002 (3)0.0213 (3)
C10.0348 (7)0.0412 (8)0.0506 (10)0.0036 (6)0.0054 (7)0.0058 (7)
C20.0311 (7)0.0375 (8)0.0540 (10)0.0019 (6)0.0063 (7)−0.0014 (7)
C30.0342 (8)0.0576 (10)0.0720 (13)−0.0010 (7)0.0043 (8)−0.0049 (9)
C40.0415 (9)0.0611 (11)0.1018 (17)−0.0098 (8)0.0271 (10)−0.0070 (11)
C50.0605 (11)0.0605 (11)0.0774 (15)−0.0026 (9)0.0271 (10)0.0139 (10)
C60.0519 (10)0.0536 (10)0.0593 (12)0.0054 (8)0.0092 (8)0.0090 (9)
C70.0390 (8)0.0344 (7)0.0503 (10)0.0048 (6)0.0075 (7)0.0000 (7)
C80.0333 (7)0.0382 (8)0.0563 (11)0.0045 (6)0.0020 (7)−0.0065 (7)
C90.0454 (9)0.0554 (10)0.0720 (13)0.0096 (8)−0.0072 (9)−0.0139 (9)
C100.0352 (9)0.0727 (13)0.1100 (19)0.0001 (9)−0.0045 (10)−0.0327 (13)
C110.0392 (9)0.0748 (13)0.121 (2)−0.0183 (9)0.0167 (11)−0.0319 (14)
C120.0499 (10)0.0556 (10)0.0871 (15)−0.0133 (8)0.0188 (10)−0.0032 (10)
C130.0351 (7)0.0404 (8)0.0616 (11)−0.0011 (6)0.0087 (7)−0.0031 (8)
C140.0401 (8)0.0526 (9)0.0453 (10)0.0095 (7)0.0015 (7)0.0017 (7)
C150.0412 (8)0.0476 (9)0.0488 (10)0.0104 (7)0.0018 (7)0.0071 (7)
C160.0467 (9)0.0584 (10)0.0678 (13)0.0059 (8)0.0118 (8)0.0026 (9)
C170.0487 (10)0.0574 (11)0.0854 (15)−0.0004 (8)0.0075 (10)0.0087 (11)
C180.0600 (11)0.0501 (10)0.0869 (15)0.0005 (9)0.0005 (10)−0.0018 (10)
C190.0562 (10)0.0511 (10)0.0705 (13)0.0136 (8)0.0047 (9)−0.0029 (9)
C200.0426 (8)0.0471 (9)0.0519 (11)0.0125 (7)0.0002 (7)0.0067 (8)
C210.0418 (8)0.0574 (10)0.0496 (10)0.0171 (7)0.0013 (7)0.0059 (8)
C220.0470 (10)0.0744 (12)0.0663 (13)0.0196 (9)0.0045 (9)−0.0018 (10)
C230.0406 (10)0.1029 (17)0.0786 (15)0.0206 (10)0.0110 (9)0.0027 (13)
C240.0348 (9)0.1053 (17)0.0897 (17)0.0044 (10)0.0036 (10)−0.0003 (14)
C250.0412 (9)0.0843 (14)0.0737 (14)0.0025 (9)−0.0006 (9)−0.0097 (11)
C260.0349 (8)0.0629 (10)0.0515 (11)0.0120 (7)−0.0029 (7)0.0022 (8)
C270.0383 (8)0.0532 (9)0.0499 (10)0.0097 (7)0.0024 (7)0.0078 (8)
C280.0527 (10)0.0496 (10)0.0714 (13)0.0093 (8)0.0104 (9)0.0101 (9)
Geometric parameters (Å, °) top
Cl1—C281.720 (2)C14—C271.530 (2)
C1—C131.470 (2)C14—H140.9800
C1—C281.522 (2)C15—C161.294 (2)
C1—C21.560 (2)C15—C201.421 (2)
C1—C271.638 (2)C16—C171.395 (3)
C2—C31.290 (2)C16—H160.9300
C2—C71.441 (2)C17—C181.394 (3)
C3—C41.455 (3)C17—H170.9300
C3—H30.9300C18—C191.302 (3)
C4—C51.411 (3)C18—H180.9300
C4—H40.9300C19—C201.390 (3)
C5—C61.280 (3)C19—H190.9300
C5—H50.9300C20—C211.375 (2)
C6—C71.440 (2)C21—C221.358 (2)
C6—H60.9300C21—C261.437 (3)
C7—C81.381 (2)C22—C231.295 (3)
C8—C91.360 (2)C22—H220.9300
C8—C131.478 (2)C23—C241.411 (3)
C9—C101.326 (3)C23—H230.9300
C9—H90.9300C24—C251.367 (3)
C10—C111.454 (4)C24—H240.9300
C10—H100.9300C25—C261.315 (3)
C11—C121.355 (3)C25—H250.9300
C11—H110.9300C27—H27A0.9700
C12—C131.331 (2)C27—H27B0.9700
C12—H120.9300C28—H28A0.9700
C14—C261.472 (2)C28—H28B0.9700
C14—C151.505 (2)
C13—C1—C28105.72 (13)C16—C15—C20117.73 (17)
C13—C1—C294.22 (12)C16—C15—C14126.93 (17)
C28—C1—C2115.17 (13)C20—C15—C14115.32 (14)
C13—C1—C27116.01 (12)C15—C16—C17116.78 (18)
C28—C1—C27108.04 (14)C15—C16—H16121.6
C2—C1—C27116.85 (12)C17—C16—H16121.6
C3—C2—C7115.17 (16)C18—C17—C16125.34 (18)
C3—C2—C1127.39 (16)C18—C17—H17117.3
C7—C2—C1117.44 (13)C16—C17—H17117.3
C2—C3—C4116.40 (17)C19—C18—C17118.73 (19)
C2—C3—H3121.8C19—C18—H18120.6
C4—C3—H3121.8C17—C18—H18120.6
C5—C4—C3127.81 (16)C18—C19—C20116.08 (18)
C5—C4—H4116.1C18—C19—H19122.0
C3—C4—H4116.1C20—C19—H19122.0
C6—C5—C4116.31 (19)C21—C20—C19129.09 (16)
C6—C5—H5121.8C21—C20—C15105.57 (15)
C4—C5—H5121.8C19—C20—C15125.33 (16)
C5—C6—C7116.61 (19)C22—C21—C20126.61 (18)
C5—C6—H6121.7C22—C21—C26124.45 (17)
C7—C6—H6121.7C20—C21—C26108.94 (15)
C8—C7—C6128.77 (16)C23—C22—C21114.3 (2)
C8—C7—C2103.51 (14)C23—C22—H22122.8
C6—C7—C2127.70 (15)C21—C22—H22122.8
C9—C8—C7125.19 (17)C22—C23—C24122.10 (19)
C9—C8—C13124.93 (16)C22—C23—H23118.9
C7—C8—C13109.88 (14)C24—C23—H23118.9
C10—C9—C8112.0 (2)C25—C24—C23124.5 (2)
C10—C9—H9124.0C25—C24—H24117.8
C8—C9—H9124.0C23—C24—H24117.8
C9—C10—C11123.34 (18)C26—C25—C24114.1 (2)
C9—C10—H10118.3C26—C25—H25122.9
C11—C10—H10118.3C24—C25—H25122.9
C12—C11—C10125.04 (19)C25—C26—C21120.52 (17)
C12—C11—H11117.5C25—C26—C14125.89 (18)
C10—C11—H11117.5C21—C26—C14113.56 (15)
C13—C12—C11112.7 (2)C14—C27—C1112.98 (13)
C13—C12—H12123.7C14—C27—H27A109.0
C11—C12—H12123.7C1—C27—H27A109.0
C12—C13—C1123.32 (17)C14—C27—H27B109.0
C12—C13—C8121.94 (17)C1—C27—H27B109.0
C1—C13—C8114.73 (13)H27A—C27—H27B107.8
C26—C14—C1596.56 (14)C1—C28—Cl1113.56 (13)
C26—C14—C27113.72 (15)C1—C28—H28A108.9
C15—C14—C27118.13 (13)Cl1—C28—H28A108.9
C26—C14—H14109.2C1—C28—H28B108.9
C15—C14—H14109.2Cl1—C28—H28B108.9
C27—C14—H14109.2H28A—C28—H28B107.7
C13—C1—C2—C3176.17 (17)C26—C14—C15—C201.81 (17)
C28—C1—C2—C366.6 (2)C27—C14—C15—C20123.19 (16)
C27—C1—C2—C3−61.8 (2)C20—C15—C16—C17−0.1 (3)
C13—C1—C2—C7−3.14 (16)C14—C15—C16—C17−178.46 (16)
C28—C1—C2—C7−112.70 (16)C15—C16—C17—C18−0.5 (3)
C27—C1—C2—C7118.88 (14)C16—C17—C18—C190.4 (3)
C7—C2—C3—C40.1 (2)C17—C18—C19—C200.4 (3)
C1—C2—C3—C4−179.23 (15)C18—C19—C20—C21179.31 (19)
C2—C3—C4—C5−0.1 (3)C18—C19—C20—C15−1.0 (3)
C3—C4—C5—C60.1 (3)C16—C15—C20—C21−179.38 (16)
C4—C5—C6—C7−0.1 (3)C14—C15—C20—C21−0.83 (19)
C5—C6—C7—C8178.42 (17)C16—C15—C20—C190.9 (3)
C5—C6—C7—C20.2 (3)C14—C15—C20—C19179.43 (16)
C3—C2—C7—C8−178.76 (14)C19—C20—C21—C22−1.2 (3)
C1—C2—C7—C80.64 (17)C15—C20—C21—C22179.06 (17)
C3—C2—C7—C6−0.2 (2)C19—C20—C21—C26179.09 (17)
C1—C2—C7—C6179.23 (15)C15—C20—C21—C26−0.64 (18)
C6—C7—C8—C93.1 (3)C20—C21—C22—C23−179.87 (19)
C2—C7—C8—C9−178.30 (15)C26—C21—C22—C23−0.2 (3)
C6—C7—C8—C13−176.25 (15)C21—C22—C23—C240.0 (3)
C2—C7—C8—C132.33 (16)C22—C23—C24—C250.1 (4)
C7—C8—C9—C10−177.88 (16)C23—C24—C25—C260.1 (3)
C13—C8—C9—C101.4 (2)C24—C25—C26—C21−0.3 (3)
C8—C9—C10—C111.2 (3)C24—C25—C26—C14177.61 (17)
C9—C10—C11—C12−2.2 (3)C22—C21—C26—C250.4 (3)
C10—C11—C12—C130.1 (3)C20—C21—C26—C25−179.91 (18)
C11—C12—C13—C1−176.77 (16)C22—C21—C26—C14−177.76 (16)
C11—C12—C13—C82.5 (3)C20—C21—C26—C142.0 (2)
C28—C1—C13—C12−58.6 (2)C15—C14—C26—C25179.82 (19)
C2—C1—C13—C12−176.21 (16)C27—C14—C26—C2555.1 (3)
C27—C1—C13—C1261.1 (2)C15—C14—C26—C21−2.17 (17)
C28—C1—C13—C8122.11 (15)C27—C14—C26—C21−126.84 (16)
C2—C1—C13—C84.48 (15)C26—C14—C27—C1−123.54 (15)
C27—C1—C13—C8−118.20 (15)C15—C14—C27—C1124.34 (16)
C9—C8—C13—C12−3.6 (3)C13—C1—C27—C1458.35 (18)
C7—C8—C13—C12175.79 (16)C28—C1—C27—C14176.78 (13)
C9—C8—C13—C1175.74 (15)C2—C1—C27—C14−51.45 (17)
C7—C8—C13—C1−4.88 (18)C13—C1—C28—Cl1179.50 (12)
C26—C14—C15—C16−179.80 (18)C2—C1—C28—Cl1−77.98 (18)
C27—C14—C15—C16−58.4 (2)C27—C1—C28—Cl154.69 (17)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C27—H27A···Cl10.972.683.075 (2)105
C10—H10···Cl1i0.932.893.573 (2)131
Symmetry codes: (i) x+1, −y+3/2, z+1/2.
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C27—H27A···Cl10.972.683.075 (2)105
Acknowledgements top

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

references
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