14-n-Butyl­dibenz­[a,h]­acridine

The crystal structure of the monoclinic form of the title compound, C₂₅H₂₁N, is influenced by the presence of the alkyl chain, whose trans conformation leads to distortion of the aromatic moiety from planarity, the dihedral angle between the two outer rings being ca 20°. The C-C-C ring angles and C-C ring distances nearest to the n-butyl substituent are perturbed from typical values to minimize the steric effect.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.054
• wR factor = 0.167
• Data-to-parameter ratio = 19.2

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

Use of alkylated acridine derivatives in molecular recognitions have made enormous strides in recent years (Pan et al., 2000). Regioselective alkylation of polycyclic benz and dibenz acridines not only improves the solubility of these compounds in common organic solvents (Ray et al. 1996), but also provides a simple path for the synthesis of alkylated molecular hosts (Halder et al., 1997).

Molecule (I) is composed of five (A, B, C, D and E) fused six-membered aromatic rings with one n-butyl chain at the para position of the central ring (Fig. 1). The conformation adopted by (I) in the solid state is affected by the presence of the alkyl chain at C3 (Fig. 2). C—C distances in the environment of the alkyl chain (C2—C3, C3—C4 and C4—C9) are rather similar to those found in monoclinic dibenz[a,h]anthracene (Robertson & White, 1956). On the other hand, the C2—C14 distance [1.470 (2) Å] is 0.08 Å larger than equivalent distance in dibenz[a,h]anthracene. All ring angles are reasonably close to ideal geometry, the presence of the alkyl chain increases the C3—C2—C14 angle [to 126.74 (15)°].

Rings A and B are reasonably planar, with mean deviations from planarity of 0.0024 and 0.0075 Å, respectively. On the other hand, rings C, D and E are less planar, the corresponding mean deviations are 0.0283, 0.0396 and 0.0278 Å, respectively, the main deviation from planarity taking place at the D ring. These values and the C1—C2—C3—C4 and C1—C2—C14—C15 torsion angles (Table 1) reflect the distortion of the molecule in order to minimize the steric interaction between ring E and the alkyl chain. As expected on the basis of basic chemical grounds and obtained using molecular mechanics calculations (GAUSSIAN98 suite of programs, UFF force field; Frisch et al., 1998), the parent compound without the alkyl chain should be planar, whereas in this case the dihedral angle between rings A and E is 19.67 (10)°. The value of the C22—C23—C24—C25 torsion angle [−178.93 (18)°] implies a trans conformation for the alkyl chain. The steric interaction between the n-butyl substituent and the E ring moves the C3—C22—C23—C24 torsion angle to 169.42 (16)°.

Relevant changes respect to monoclinic dibenz[a,h]anthracene crystal take place. The presence of the alkyl chain provokes the change of symmetry space group (H—M) from P21 to C2/c, which implies modifications at β cell angle [93.3220 (10) versus 103.5°], cell lengths a [19.5507 (11) versus 6.59 Å] and b [12.7195 (7) versus 7.84 Å], and the number of cell formula units Z increases from 2 to 8. Within the three-dimensional network, it is noticeable that the alkyl chain of the one molecule is directed towards the N atom of the next molecule in the same layer (Fig. 3), thus making the packing more effective.

S2. Experimental

In an attempt to synthesize monoalkylated polyazaarenes, we heated a mixture of chloroaldehyde with 3-naphthylamine to get dihydrodibenzacridine, which on dehydrogenation with Pd—C (10%) in p-cymene produced dihydrodibenz[a,h]acridine (Halder et al., 1989). The direct alkylation of dibenz[a,h]acridine with three equivalents of n-butyllithium produced the title compound in 70% yield (see Scheme). Single crystals were obtained by slow evaporation from a chloroform–petroleum ether solution.

Computing details

Data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997a); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997a); molecular graphics: SHELXTL (Sheldrick, 1997b); software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. View of the title molecule, showing 50% probability displacement ellipsoids. H atoms have been omitted for clarity.
	Fig. 2. Reduced packing diagram of the title compound, showing the orientation of the alkyl chain.

14-n-Butyldibenz[a,h]acridine

Crystal data

C25H21N	F(000) = 1424
Mr = 335.43	Dx = 1.215 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 10111 reflections
a = 19.5507 (11) Å	θ = 1.4–28.4°
b = 12.7195 (7) Å	µ = 0.07 mm^−1
c = 14.7732 (8) Å	T = 298 K
β = 93.322 (1)°	Block, yellow
V = 3667.6 (4) Å^3	0.50 × 0.25 × 0.25 mm
Z = 8

Data collection

Bruker SMART 1K CCD area-detector diffractometer	4539 independent reflections
Radiation source: fine-focus sealed tube	2208 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.035
ϕ and ω scans	θmax = 28.3°, θmin = 1.9°
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick, 1996)	h = −25→26
Tmin = 0.966, Tmax = 0.983	k = −14→16
12785 measured reflections	l = −17→19

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.167	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0845P)^2] where P = (Fo^2 + 2Fc^2)/3
4539 reflections	(Δ/σ)max < 0.001
236 parameters	Δρmax = 0.17 e Å^−3
0 restraints	Δρmin = −0.16 e Å^−3

Special details

Experimental. Data was collected using a Siemens SMART CCD based diffractometer operating at room temperature. Data was measured using omega scans of 0.3 degrees per frame for 60 s. A total of 1271 frames were collected. The first 50 frames were recollected at the end of each set of frames.

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 (Ų)

	x	y	z	Uiso*/Ueq
N1	0.20712 (7)	0.94371 (11)	0.12336 (9)	0.0606 (4)
C1	0.24753 (8)	0.97813 (12)	0.05954 (10)	0.0579 (4)
C2	0.30655 (8)	0.92382 (12)	0.03031 (10)	0.0548 (4)
C3	0.31644 (8)	0.82032 (12)	0.06486 (10)	0.0553 (4)
C4	0.27295 (8)	0.78358 (12)	0.13108 (10)	0.0562 (4)
C5	0.21998 (8)	0.84883 (12)	0.16050 (10)	0.0560 (4)
C6	0.17452 (9)	0.81306 (13)	0.22835 (11)	0.0619 (4)
C7	0.18200 (9)	0.71022 (14)	0.26268 (11)	0.0667 (5)
C8	0.23510 (10)	0.64576 (14)	0.23078 (12)	0.0728 (5)
H8	0.2400	0.5777	0.2532	0.087*
C9	0.27818 (10)	0.67897 (13)	0.16997 (11)	0.0670 (5)
H9	0.3124	0.6339	0.1521	0.080*
C10	0.13686 (11)	0.67508 (17)	0.32735 (13)	0.0850 (6)
H10	0.1411	0.6069	0.3498	0.102*
C11	0.08733 (12)	0.7390 (2)	0.35754 (15)	0.0969 (7)
H11	0.0584	0.7148	0.4008	0.116*
C12	0.08009 (11)	0.8407 (2)	0.32361 (15)	0.0961 (7)
H12	0.0460	0.8842	0.3440	0.115*
C13	0.12285 (9)	0.87702 (17)	0.26036 (13)	0.0786 (5)
H13	0.1175	0.9452	0.2384	0.094*
C14	0.34738 (8)	0.97676 (12)	−0.03665 (10)	0.0586 (4)
C15	0.32027 (9)	1.06796 (13)	−0.08092 (11)	0.0632 (5)
C16	0.25865 (10)	1.11449 (14)	−0.05257 (12)	0.0726 (5)
H16	0.2411	1.1737	−0.0826	0.087*
C17	0.22571 (9)	1.07480 (14)	0.01609 (12)	0.0705 (5)
H17	0.1879	1.1102	0.0364	0.085*
C18	0.35498 (11)	1.11460 (16)	−0.15061 (13)	0.0789 (6)
H18	0.3357	1.1727	−0.1805	0.095*
C19	0.41616 (12)	1.07725 (18)	−0.17583 (14)	0.0913 (6)
H19	0.4375	1.1070	−0.2243	0.110*
C20	0.44616 (11)	0.99406 (18)	−0.12793 (15)	0.0924 (6)
H20	0.4893	0.9705	−0.1421	0.111*
C21	0.41315 (9)	0.94612 (15)	−0.05999 (13)	0.0759 (5)
H21	0.4350	0.8914	−0.0282	0.091*
C22	0.36725 (9)	0.74302 (13)	0.02976 (10)	0.0645 (5)
H22	0.3795	0.7660	−0.0298	0.077*
H22B	0.3450	0.6751	0.0225	0.077*
C23	0.43282 (9)	0.72905 (14)	0.08958 (12)	0.0711 (5)
H23	0.4211	0.7182	0.1518	0.085*
H23B	0.4600	0.7927	0.0876	0.085*
C24	0.47531 (11)	0.63607 (17)	0.05943 (14)	0.0941 (7)
H24	0.4473	0.5731	0.0600	0.113*
H24B	0.4872	0.6479	−0.0026	0.113*
C25	0.53920 (12)	0.6175 (2)	0.1164 (2)	0.1271 (9)
H25	0.5611	0.5547	0.0965	0.191*
H25B	0.5283	0.6096	0.1786	0.191*
H25C	0.5696	0.6762	0.1110	0.191*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0662 (8)	0.0527 (8)	0.0618 (8)	0.0036 (7)	−0.0049 (7)	0.0032 (6)
C1	0.0640 (10)	0.0484 (9)	0.0598 (10)	0.0018 (8)	−0.0100 (8)	0.0010 (7)
C2	0.0638 (10)	0.0491 (9)	0.0497 (9)	0.0007 (8)	−0.0116 (8)	−0.0021 (7)
C3	0.0650 (10)	0.0490 (9)	0.0499 (9)	0.0048 (8)	−0.0126 (8)	−0.0051 (7)
C4	0.0696 (10)	0.0480 (9)	0.0491 (9)	0.0006 (8)	−0.0126 (8)	−0.0014 (7)
C5	0.0610 (9)	0.0518 (9)	0.0535 (9)	0.0001 (8)	−0.0123 (8)	−0.0021 (7)
C6	0.0659 (10)	0.0620 (11)	0.0565 (10)	−0.0061 (9)	−0.0074 (8)	0.0011 (8)
C7	0.0769 (12)	0.0631 (11)	0.0583 (10)	−0.0089 (9)	−0.0108 (9)	0.0019 (8)
C8	0.1029 (14)	0.0507 (10)	0.0635 (11)	−0.0050 (10)	−0.0066 (11)	0.0079 (8)
C9	0.0894 (13)	0.0511 (10)	0.0592 (10)	0.0084 (9)	−0.0069 (10)	0.0003 (8)
C10	0.0969 (15)	0.0785 (14)	0.0788 (13)	−0.0207 (12)	−0.0031 (12)	0.0151 (11)
C11	0.0874 (15)	0.1040 (19)	0.1008 (16)	−0.0163 (14)	0.0175 (13)	0.0124 (14)
C12	0.0787 (13)	0.1072 (19)	0.1037 (16)	0.0038 (13)	0.0173 (13)	0.0124 (14)
C13	0.0721 (12)	0.0795 (13)	0.0839 (13)	0.0068 (11)	0.0034 (11)	0.0105 (10)
C14	0.0645 (10)	0.0546 (10)	0.0554 (9)	−0.0017 (8)	−0.0092 (8)	−0.0021 (8)
C15	0.0723 (11)	0.0556 (10)	0.0600 (10)	−0.0050 (9)	−0.0098 (9)	0.0057 (8)
C16	0.0825 (12)	0.0558 (11)	0.0776 (12)	0.0090 (9)	−0.0117 (10)	0.0139 (9)
C17	0.0742 (11)	0.0572 (11)	0.0794 (12)	0.0117 (9)	−0.0025 (10)	0.0099 (9)
C18	0.0880 (14)	0.0700 (12)	0.0772 (13)	−0.0050 (11)	−0.0092 (11)	0.0170 (10)
C19	0.0969 (16)	0.0930 (16)	0.0848 (14)	−0.0069 (13)	0.0113 (12)	0.0254 (12)
C20	0.0811 (13)	0.0952 (16)	0.1022 (15)	0.0012 (12)	0.0165 (12)	0.0165 (13)
C21	0.0754 (12)	0.0724 (12)	0.0796 (12)	0.0033 (10)	0.0017 (10)	0.0121 (10)
C22	0.0826 (11)	0.0506 (9)	0.0594 (10)	0.0057 (9)	−0.0039 (9)	−0.0047 (8)
C23	0.0761 (12)	0.0660 (11)	0.0705 (11)	0.0144 (9)	−0.0015 (9)	0.0022 (9)
C24	0.0941 (15)	0.0865 (15)	0.1030 (16)	0.0291 (12)	0.0155 (13)	−0.0044 (12)
C25	0.0955 (17)	0.114 (2)	0.172 (2)	0.0417 (15)	0.0036 (17)	−0.0025 (19)

Geometric parameters (Å, º)

N1—C1	1.338 (2)	C14—C15	1.419 (2)
N1—C5	1.3433 (19)	C15—C18	1.398 (2)
C1—C2	1.433 (2)	C15—C16	1.427 (2)
C1—C17	1.440 (2)	C16—C17	1.332 (2)
C2—C3	1.421 (2)	C16—H16	0.9300
C2—C14	1.470 (2)	C17—H17	0.9300
C3—C4	1.412 (2)	C18—C19	1.359 (3)
C3—C22	1.511 (2)	C18—H18	0.9300
C4—C5	1.415 (2)	C19—C20	1.384 (3)
C4—C9	1.451 (2)	C19—H19	0.9300
C5—C6	1.451 (2)	C20—C21	1.368 (3)
C6—C13	1.400 (2)	C20—H20	0.9300
C6—C7	1.407 (2)	C21—H21	0.9300
C7—C10	1.410 (3)	C22—C23	1.525 (2)
C7—C8	1.424 (3)	C22—H22	0.9700
C8—C9	1.335 (2)	C22—H22B	0.9700
C8—H8	0.9300	C23—C24	1.526 (3)
C9—H9	0.9300	C23—H23	0.9700
C10—C11	1.359 (3)	C23—H23B	0.9700
C10—H10	0.9300	C24—C25	1.484 (3)
C11—C12	1.391 (3)	C24—H24	0.9700
C11—H11	0.9300	C24—H24B	0.9700
C12—C13	1.370 (3)	C25—H25	0.9600
C12—H12	0.9300	C25—H25B	0.9600
C13—H13	0.9300	C25—H25C	0.9600
C14—C21	1.406 (2)
C1—N1—C5	118.52 (14)	C18—C15—C16	119.64 (17)
N1—C1—C2	124.98 (14)	C14—C15—C16	120.19 (16)
N1—C1—C17	114.94 (15)	C17—C16—C15	121.33 (16)
C2—C1—C17	120.01 (16)	C17—C16—H16	119.3
C3—C2—C1	115.69 (15)	C15—C16—H16	119.3
C3—C2—C14	126.74 (15)	C16—C17—C1	121.29 (17)
C1—C2—C14	117.40 (14)	C16—C17—H17	119.4
C4—C3—C2	118.71 (14)	C1—C17—H17	119.4
C4—C3—C22	117.17 (14)	C19—C18—C15	121.74 (18)
C2—C3—C22	123.93 (15)	C19—C18—H18	119.1
C3—C4—C5	119.96 (14)	C15—C18—H18	119.1
C3—C4—C9	123.12 (15)	C18—C19—C20	118.7 (2)
C5—C4—C9	116.90 (16)	C18—C19—H19	120.6
N1—C5—C4	121.63 (15)	C20—C19—H19	120.6
N1—C5—C6	117.15 (15)	C21—C20—C19	120.8 (2)
C4—C5—C6	121.12 (15)	C21—C20—H20	119.6
C13—C6—C7	118.69 (17)	C19—C20—H20	119.6
C13—C6—C5	122.26 (16)	C20—C21—C14	122.25 (18)
C7—C6—C5	119.04 (16)	C20—C21—H21	118.9
C6—C7—C10	118.85 (18)	C14—C21—H21	118.9
C6—C7—C8	118.58 (17)	C3—C22—C23	115.11 (13)
C10—C7—C8	122.57 (18)	C3—C22—H22	108.5
C9—C8—C7	122.74 (17)	C23—C22—H22	108.5
C9—C8—H8	118.6	C3—C22—H22B	108.5
C7—C8—H8	118.6	C23—C22—H22B	108.5
C8—C9—C4	121.60 (17)	H22—C22—H22B	107.5
C8—C9—H9	119.2	C22—C23—C24	112.00 (15)
C4—C9—H9	119.2	C22—C23—H23	109.2
C11—C10—C7	121.2 (2)	C24—C23—H23	109.2
C11—C10—H10	119.4	C22—C23—H23B	109.2
C7—C10—H10	119.4	C24—C23—H23B	109.2
C10—C11—C12	119.8 (2)	H23—C23—H23B	107.9
C10—C11—H11	120.1	C25—C24—C23	114.34 (18)
C12—C11—H11	120.1	C25—C24—H24	108.7
C13—C12—C11	120.4 (2)	C23—C24—H24	108.7
C13—C12—H12	119.8	C25—C24—H24B	108.7
C11—C12—H12	119.8	C23—C24—H24B	108.7
C12—C13—C6	121.0 (2)	H24—C24—H24B	107.6
C12—C13—H13	119.5	C24—C25—H25	109.5
C6—C13—H13	119.5	C24—C25—H25B	109.5
C21—C14—C15	115.86 (16)	H25—C25—H25B	109.5
C21—C14—C2	125.33 (15)	C24—C25—H25C	109.5
C15—C14—C2	118.79 (15)	H25—C25—H25C	109.5
C18—C15—C14	120.14 (17)	H25B—C25—H25C	109.5
C5—N1—C1—C2	−3.5 (2)	C5—C4—C9—C8	−0.1 (2)
C5—N1—C1—C17	173.30 (13)	C6—C7—C10—C11	−0.9 (3)
N1—C1—C2—C3	8.1 (2)	C8—C7—C10—C11	178.98 (18)
C17—C1—C2—C3	−168.54 (14)	C7—C10—C11—C12	0.8 (3)
N1—C1—C2—C14	−176.25 (13)	C10—C11—C12—C13	−0.4 (3)
C17—C1—C2—C14	7.1 (2)	C11—C12—C13—C6	0.1 (3)
C1—C2—C3—C4	−6.52 (19)	C7—C6—C13—C12	−0.2 (3)
C14—C2—C3—C4	178.33 (13)	C5—C6—C13—C12	179.14 (17)
C1—C2—C3—C22	168.36 (13)	C3—C2—C14—C21	−17.9 (2)
C14—C2—C3—C22	−6.8 (2)	C1—C2—C14—C21	166.99 (15)
C2—C3—C4—C5	1.2 (2)	C3—C2—C14—C15	163.67 (14)
C22—C3—C4—C5	−174.05 (13)	C1—C2—C14—C15	−11.4 (2)
C2—C3—C4—C9	179.29 (14)	C21—C14—C15—C18	7.2 (2)
C22—C3—C4—C9	4.1 (2)	C2—C14—C15—C18	−174.30 (14)
C1—N1—C5—C4	−2.7 (2)	C21—C14—C15—C16	−170.79 (16)
C1—N1—C5—C6	−178.96 (13)	C2—C14—C15—C16	7.8 (2)
C3—C4—C5—N1	3.8 (2)	C18—C15—C16—C17	−177.18 (16)
C9—C4—C5—N1	−174.45 (13)	C14—C15—C16—C17	0.8 (3)
C3—C4—C5—C6	179.93 (13)	C15—C16—C17—C1	−5.4 (3)
C9—C4—C5—C6	1.7 (2)	N1—C1—C17—C16	−175.68 (15)
N1—C5—C6—C13	−5.4 (2)	C2—C1—C17—C16	1.3 (2)
C4—C5—C6—C13	178.29 (15)	C14—C15—C18—C19	−2.4 (3)
N1—C5—C6—C7	173.96 (13)	C16—C15—C18—C19	175.55 (18)
C4—C5—C6—C7	−2.3 (2)	C15—C18—C19—C20	−3.3 (3)
C13—C6—C7—C10	0.6 (2)	C18—C19—C20—C21	3.8 (3)
C5—C6—C7—C10	−178.81 (14)	C19—C20—C21—C14	1.3 (3)
C13—C6—C7—C8	−179.28 (15)	C15—C14—C21—C20	−6.7 (3)
C5—C6—C7—C8	1.3 (2)	C2—C14—C21—C20	174.86 (16)
C6—C7—C8—C9	0.3 (2)	C4—C3—C22—C23	−81.85 (18)
C10—C7—C8—C9	−179.59 (16)	C2—C3—C22—C23	103.20 (18)
C7—C8—C9—C4	−0.9 (3)	C3—C22—C23—C24	169.42 (16)
C3—C4—C9—C8	−178.25 (15)	C22—C23—C24—C25	−178.93 (18)