N-(9H-Fluoren-9-yl­idene)-4-methyl­aniline

Bai, S.-Z.; Lou, X.-H.; Li, H.-M.; Shi, H.

doi:10.1107/S1600536809020765

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1545

doi:10.1107/S1600536809020765

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N-(9H-Fluoren-9-ylidene)-4-methylaniline

Su-Zhen Bai,^a Xin-Hua Lou,^b ^* Hong-Mei Li ^c and Hui Shi ^a

^aCollege of Chemistry and Chemical Engineering, Pingdingshan University, Pingdingshan 467002, People's Republic of China, ^bCollege of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 471022, People's Republic of China, and ^cChemical Engineering and Pharmaceutics School, Henan University of Science and Technology, Luoyang 471003, People's Republic of China
^*Correspondence e-mail: lxh-9802@163.com

(Received 27 May 2009; accepted 1 June 2009; online 10 June 2009)

In the title compound, C₂₀H₁₅N, the fluorene unit is essentially planar [r.m.s. deviation 0.0334 Å] and the benzene ring bound to the imine N atom bears a methyl group which is nearly coplanar [dihedral angle 0.5 (1)°]. The dihedral angle between the substituent benzene ring and the 9H-fluoren-9-imine unit is 71.1 (3)°. Intermolecular π–π interactions between the benzene rings of adjacent fluorene units [centroid–centroid distance 3.8081 (13) Å] are present in the crystal structure, resulting in a one-dimensional supramolecular architecture.

Related literature

For the properties of Schiff bases, see: Xu et al. (2007 ); Tanaka et al. (2006 ). For the properties of fluorene derivatives, see: Saragi et al. (2004 ). For related structures, see: Glagovich et al. (2004 ); Peters et al. (1998 ); Pierre et al. (1997 ).

Experimental

Crystal data

C₂₀H₁₅N
M_r = 269.33
Monoclinic, P 2₁ /n
a = 5.6423 (10) Å
b = 12.187 (2) Å
c = 21.310 (4) Å
β = 94.441 (2)°
V = 1460.9 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 294 K
0.35 × 0.17 × 0.09 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.976, T_max = 0.994
10793 measured reflections
2711 independent reflections
1779 reflections with I > 2σ(I)
R_int = 0.042

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.115
S = 1.01
2711 reflections
192 parameters
H-atom parameters constrained
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Data collection: SMART (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809020765/si2179sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809020765/si2179Isup2.hkl

checkCIF report

Comment top

Schiff bases have received much attention during the past decades because of their strong coordination capability and diverse biological activities (Xu et al., 2007; Tanaka et al., 2006). In addition, fluorene derivatives have found many applications in chemistry, especially in the optoelectronic area (Saragi et al., 2004). In view of these important properties, the crystal structure of the title compond has been determined.

In the title compound (Fig.1), the C12—N1—C14 angle of 120.76 (15)° and the N1—C12 bond distance of 1.278 (2)Å are in close agreement with the similar Nfluorenylideneaniline (Glagovich et al., 2004; Peters et al., 1998; Pierre et al., 1997). The fluorene unit is essentially planar and the benzene ring bound to the imine N atom bears a methyl that is nearly coplanar. The dihedral angle between the substituent benzene ring and the 9H-fluoren-9-imine unit is 108.9 (3)°. Intermolecular π···π interactions between the benzene rings of adjacent fluorene units [centroid-centroid distance is 3.8081 (13) Å, the average perpendicular distance is 3.469 Å, the dihedral angle between the rings is 3.7°, symmetry code = -1 + x, y, z] are present in the crystal structure, resulting in a one-dimensional supramolecular architecture (Fig. 2).

Related literature top

For the properties of Schiff bases, see: Xu et al. (2007); Tanaka et al. (2006). For the properties of fluorene derivatives, see: Saragi et al. (2004). For related structures, see: Glagovich et al. (2004); Peters et al. (1998); Pierre et al. (1997).

Experimental top

The title compound was obtained from the condensation reaction of 9-fluorenone and 4-methylaniline as described in literature (Glagovich et al., 2004) and recrystallized from ethanol solution at room temperature to give the desired product as yellow crystals suitable for single-crystal X-ray diffraction.

Computing details top

Data collection: SMART (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound with displacement ellipsoids at the 30% probability level. H atoms are omitted for clarity.
	Fig. 2. Partial view of the crystal packing showing the formation of the chain motif of molecules formed by the intermolecular π···π interactions. H atoms are omitted for clarity.

N-(9H-Fluoren-9-ylidene)-4-methylaniline top

Crystal data top

C₂₀H₁₅N	F(000) = 568
M_r = 269.33	D_x = 1.225 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 5.6423 (10) Å	Cell parameters from 1911 reflections
b = 12.187 (2) Å	θ = 2.5–22.3°
c = 21.310 (4) Å	µ = 0.07 mm⁻¹
β = 94.441 (2)°	T = 294 K
V = 1460.9 (5) Å³	Block, yellow
Z = 4	0.35 × 0.17 × 0.09 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2711 independent reflections
Radiation source: fine-focus sealed tube	1779 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.042
phi and ω scans	θ_max = 25.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −6→6
T_min = 0.976, T_max = 0.994	k = −14→14
10793 measured reflections	l = −25→25

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.042	H-atom parameters constrained
wR(F²) = 0.115	w = 1/[σ²(F_o²) + (0.052P)² + 0.1725P] where P = (F_o² + 2F_c²)/3
S = 1.01	(Δ/σ)_max < 0.001
2711 reflections	Δρ_max = 0.13 e Å⁻³
192 parameters	Δρ_min = −0.14 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0105 (19)

Crystal data top

C₂₀H₁₅N	V = 1460.9 (5) Å³
M_r = 269.33	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 5.6423 (10) Å	µ = 0.07 mm⁻¹
b = 12.187 (2) Å	T = 294 K
c = 21.310 (4) Å	0.35 × 0.17 × 0.09 mm
β = 94.441 (2)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	2711 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1779 reflections with I > 2σ(I)
T_min = 0.976, T_max = 0.994	R_int = 0.042
10793 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.115	H-atom parameters constrained
S = 1.01	Δρ_max = 0.13 e Å⁻³
2711 reflections	Δρ_min = −0.14 e Å⁻³
192 parameters

Special details top

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) top

	x	y	z	U_iso*/U_eq
C1	0.0001 (3)	0.30235 (15)	0.13059 (9)	0.0507 (5)
H1	−0.0938	0.3086	0.0929	0.061*
C2	−0.0545 (4)	0.36053 (16)	0.18339 (10)	0.0582 (5)
H2	−0.1869	0.4062	0.1810	0.070*
C3	0.0836 (4)	0.35188 (16)	0.23918 (10)	0.0604 (5)
H3	0.0452	0.3931	0.2737	0.072*
C4	0.2787 (3)	0.28289 (15)	0.24478 (9)	0.0544 (5)
H4	0.3701	0.2762	0.2828	0.065*
C5	0.3348 (3)	0.22414 (13)	0.19248 (8)	0.0435 (4)
C6	0.5230 (3)	0.14217 (13)	0.18583 (8)	0.0433 (4)
C7	0.7076 (3)	0.10822 (14)	0.22712 (9)	0.0508 (5)
H7	0.7270	0.1372	0.2676	0.061*
C8	0.8643 (3)	0.03010 (15)	0.20743 (9)	0.0549 (5)
H8	0.9901	0.0065	0.2349	0.066*
C9	0.8350 (3)	−0.01288 (16)	0.14735 (9)	0.0557 (5)
H9	0.9409	−0.0657	0.1350	0.067*
C10	0.6513 (3)	0.02124 (14)	0.10530 (9)	0.0506 (5)
H10	0.6328	−0.0077	0.0648	0.061*
C11	0.4954 (3)	0.09953 (13)	0.12487 (8)	0.0432 (4)
C12	0.2980 (3)	0.15766 (13)	0.08907 (8)	0.0440 (4)
C13	0.1986 (3)	0.23442 (13)	0.13519 (8)	0.0428 (4)
C14	0.0834 (3)	0.21043 (15)	−0.00479 (8)	0.0481 (5)
C15	−0.1301 (3)	0.17101 (16)	−0.03143 (9)	0.0544 (5)
H15	−0.1735	0.0986	−0.0246	0.065*
C16	−0.2793 (4)	0.23849 (16)	−0.06821 (9)	0.0598 (5)
H16	−0.4241	0.2110	−0.0852	0.072*
C17	−0.2197 (4)	0.34635 (17)	−0.08065 (9)	0.0579 (5)
C18	−0.0037 (4)	0.38372 (16)	−0.05457 (9)	0.0612 (5)
H18	0.0417	0.4554	−0.0625	0.073*
C19	0.1475 (4)	0.31784 (16)	−0.01699 (9)	0.0592 (5)
H19	0.2921	0.3454	0.0001	0.071*
C20	−0.3829 (4)	0.4195 (2)	−0.12150 (12)	0.0880 (8)
H20A	−0.3234	0.4263	−0.1623	0.132*
H20B	−0.3899	0.4907	−0.1024	0.132*
H20C	−0.5393	0.3880	−0.1257	0.132*
N1	0.2459 (3)	0.14086 (12)	0.03045 (7)	0.0521 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0542 (11)	0.0462 (10)	0.0518 (11)	0.0015 (9)	0.0048 (9)	0.0011 (9)
C2	0.0594 (12)	0.0508 (11)	0.0659 (14)	0.0066 (9)	0.0144 (11)	−0.0045 (10)
C3	0.0717 (14)	0.0513 (12)	0.0600 (13)	0.0007 (10)	0.0164 (11)	−0.0119 (10)
C4	0.0629 (12)	0.0494 (11)	0.0507 (11)	−0.0054 (9)	0.0037 (9)	−0.0071 (9)
C5	0.0486 (10)	0.0379 (9)	0.0443 (10)	−0.0061 (8)	0.0062 (8)	−0.0038 (8)
C6	0.0477 (10)	0.0395 (9)	0.0429 (10)	−0.0065 (8)	0.0040 (8)	0.0014 (8)
C7	0.0565 (11)	0.0494 (11)	0.0457 (11)	−0.0039 (9)	−0.0005 (9)	0.0003 (9)
C8	0.0497 (11)	0.0555 (12)	0.0587 (13)	0.0015 (9)	−0.0008 (10)	0.0083 (10)
C9	0.0585 (12)	0.0521 (11)	0.0578 (13)	0.0085 (9)	0.0123 (10)	0.0071 (10)
C10	0.0630 (12)	0.0441 (10)	0.0455 (11)	0.0034 (9)	0.0102 (9)	0.0023 (8)
C11	0.0497 (10)	0.0365 (9)	0.0438 (10)	−0.0017 (8)	0.0053 (8)	0.0022 (8)
C12	0.0509 (11)	0.0381 (9)	0.0434 (11)	−0.0027 (8)	0.0064 (8)	0.0007 (8)
C13	0.0494 (10)	0.0350 (9)	0.0446 (10)	−0.0043 (8)	0.0075 (8)	−0.0004 (8)
C14	0.0591 (12)	0.0486 (10)	0.0366 (10)	0.0046 (9)	0.0029 (9)	−0.0027 (8)
C15	0.0632 (12)	0.0498 (11)	0.0502 (11)	−0.0031 (10)	0.0038 (10)	0.0021 (9)
C16	0.0562 (12)	0.0647 (13)	0.0572 (12)	−0.0059 (10)	−0.0030 (10)	0.0009 (10)
C17	0.0627 (13)	0.0626 (13)	0.0478 (11)	0.0034 (10)	0.0006 (10)	0.0082 (10)
C18	0.0700 (14)	0.0521 (12)	0.0610 (13)	−0.0019 (10)	0.0020 (11)	0.0089 (10)
C19	0.0609 (12)	0.0554 (12)	0.0597 (13)	−0.0027 (10)	−0.0046 (10)	0.0022 (10)
C20	0.0844 (17)	0.0904 (18)	0.0862 (18)	0.0081 (14)	−0.0126 (14)	0.0261 (14)
N1	0.0638 (10)	0.0489 (9)	0.0431 (9)	0.0066 (8)	0.0002 (8)	−0.0012 (7)

Geometric parameters (Å, º) top

C1—C2	1.385 (3)	C10—H10	0.9300
C1—C13	1.390 (2)	C11—C12	1.481 (2)
C1—H1	0.9300	C12—N1	1.278 (2)
C2—C3	1.374 (3)	C12—C13	1.497 (2)
C2—H2	0.9300	C14—C15	1.378 (2)
C3—C4	1.383 (3)	C14—C19	1.388 (3)
C3—H3	0.9300	C14—N1	1.420 (2)
C4—C5	1.382 (2)	C15—C16	1.378 (3)
C4—H4	0.9300	C15—H15	0.9300
C5—C13	1.397 (2)	C16—C17	1.387 (3)
C5—C6	1.473 (2)	C16—H16	0.9300
C6—C7	1.374 (2)	C17—C18	1.377 (3)
C6—C11	1.397 (2)	C17—C20	1.509 (3)
C7—C8	1.386 (3)	C18—C19	1.381 (3)
C7—H7	0.9300	C18—H18	0.9300
C8—C9	1.381 (3)	C19—H19	0.9300
C8—H8	0.9300	C20—H20A	0.9600
C9—C10	1.381 (2)	C20—H20B	0.9600
C9—H9	0.9300	C20—H20C	0.9600
C10—C11	1.384 (2)

C2—C1—C13	118.45 (18)	C6—C11—C12	109.05 (15)
C2—C1—H1	120.8	N1—C12—C11	122.27 (16)
C13—C1—H1	120.8	N1—C12—C13	132.28 (16)
C3—C2—C1	121.13 (18)	C11—C12—C13	105.42 (14)
C3—C2—H2	119.4	C1—C13—C5	120.05 (16)
C1—C2—H2	119.4	C1—C13—C12	131.81 (16)
C2—C3—C4	121.03 (18)	C5—C13—C12	108.00 (15)
C2—C3—H3	119.5	C15—C14—C19	118.94 (17)
C4—C3—H3	119.5	C15—C14—N1	121.18 (17)
C5—C4—C3	118.41 (18)	C19—C14—N1	119.68 (17)
C5—C4—H4	120.8	C16—C15—C14	120.18 (18)
C3—C4—H4	120.8	C16—C15—H15	119.9
C4—C5—C13	120.91 (17)	C14—C15—H15	119.9
C4—C5—C6	129.85 (17)	C15—C16—C17	121.85 (19)
C13—C5—C6	109.18 (15)	C15—C16—H16	119.1
C7—C6—C11	120.53 (16)	C17—C16—H16	119.1
C7—C6—C5	131.23 (16)	C18—C17—C16	117.14 (18)
C11—C6—C5	108.22 (15)	C18—C17—C20	121.3 (2)
C6—C7—C8	118.85 (18)	C16—C17—C20	121.6 (2)
C6—C7—H7	120.6	C17—C18—C19	121.97 (19)
C8—C7—H7	120.6	C17—C18—H18	119.0
C9—C8—C7	120.51 (18)	C19—C18—H18	119.0
C9—C8—H8	119.7	C18—C19—C14	119.90 (18)
C7—C8—H8	119.7	C18—C19—H19	120.1
C10—C9—C8	121.14 (18)	C14—C19—H19	120.1
C10—C9—H9	119.4	C17—C20—H20A	109.5
C8—C9—H9	119.4	C17—C20—H20B	109.5
C9—C10—C11	118.36 (17)	H20A—C20—H20B	109.5
C9—C10—H10	120.8	C17—C20—H20C	109.5
C11—C10—H10	120.8	H20A—C20—H20C	109.5
C10—C11—C6	120.60 (17)	H20B—C20—H20C	109.5
C10—C11—C12	130.17 (16)	C12—N1—C14	120.76 (15)

C13—C1—C2—C3	0.1 (3)	C2—C1—C13—C5	1.4 (3)
C1—C2—C3—C4	−1.4 (3)	C2—C1—C13—C12	176.50 (17)
C2—C3—C4—C5	1.2 (3)	C4—C5—C13—C1	−1.6 (3)
C3—C4—C5—C13	0.3 (3)	C6—C5—C13—C1	176.08 (15)
C3—C4—C5—C6	−176.88 (17)	C4—C5—C13—C12	−177.78 (15)
C4—C5—C6—C7	−6.8 (3)	C6—C5—C13—C12	−0.07 (18)
C13—C5—C6—C7	175.76 (17)	N1—C12—C13—C1	8.8 (3)
C4—C5—C6—C11	175.26 (18)	C11—C12—C13—C1	−173.40 (17)
C13—C5—C6—C11	−2.18 (18)	N1—C12—C13—C5	−175.62 (18)
C11—C6—C7—C8	−0.7 (3)	C11—C12—C13—C5	2.14 (17)
C5—C6—C7—C8	−178.41 (17)	C19—C14—C15—C16	−1.7 (3)
C6—C7—C8—C9	−0.1 (3)	N1—C14—C15—C16	−176.54 (17)
C7—C8—C9—C10	0.6 (3)	C14—C15—C16—C17	1.2 (3)
C8—C9—C10—C11	−0.3 (3)	C15—C16—C17—C18	0.0 (3)
C9—C10—C11—C6	−0.4 (3)	C15—C16—C17—C20	179.4 (2)
C9—C10—C11—C12	174.14 (17)	C16—C17—C18—C19	−0.7 (3)
C7—C6—C11—C10	1.0 (3)	C20—C17—C18—C19	179.9 (2)
C5—C6—C11—C10	179.15 (15)	C17—C18—C19—C14	0.2 (3)
C7—C6—C11—C12	−174.66 (15)	C15—C14—C19—C18	1.0 (3)
C5—C6—C11—C12	3.53 (18)	N1—C14—C19—C18	175.92 (17)
C10—C11—C12—N1	−0.5 (3)	C11—C12—N1—C14	−169.33 (16)
C6—C11—C12—N1	174.52 (16)	C13—C12—N1—C14	8.1 (3)
C10—C11—C12—C13	−178.57 (17)	C15—C14—N1—C12	−115.92 (19)
C6—C11—C12—C13	−3.52 (18)	C19—C14—N1—C12	69.2 (2)

Experimental details

Crystal data
Chemical formula	C₂₀H₁₅N
M_r	269.33
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	294
a, b, c (Å)	5.6423 (10), 12.187 (2), 21.310 (4)
β (°)	94.441 (2)
V (Å³)	1460.9 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.35 × 0.17 × 0.09

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.976, 0.994
No. of measured, independent and observed [I > 2σ(I)] reflections	10793, 2711, 1779
R_int	0.042
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.115, 1.01
No. of reflections	2711
No. of parameters	192
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.14

Computer programs: SMART (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported by the High-Level Personnel to Start Research Fund of Pingdingshan University (No. 2006044).

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