10-Fluoro-6,7-di­hydro-5H-benzo­[6,7]­cyclo­hepta­[1,2-b]­quinoline

In the title compound, C₁₈H₁₄FN, the quinoline and benzene rings are essentially planar, and the two aromatic ring planes make a dihedral angle of 46.3 (1)°. The cyclo­heptane ring adopts a half-chair conformation.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.054
• wR factor = 0.148
• Data-to-parameter ratio = 18.2

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

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S1. Comment

Polycyclic aromatic hydrocarbons (PAHs) are well known enviromental pollutants (Dong et al., 1977; Harvey, 1991) and have been intensively investigated in carcinogenic studies (Harvey, 1991). Interestingly, the introduction of one F atom at a particular position has a significant effect on the carcinogenic activity of the PAHs (Harvey & Cortez, 1997; Zajc, 1999). Pan et al. (2001) focus on the synthesis, characterization and bioactivity of fluoro-polycyclic azaarenes (PAAs) in order to extend the carcinogenic studies, and have isolated the title compound, (I). An X-ray structure determination of (I) was undertaken to establish the conformation of the structure.

In compound (I), the bond lengths and angles show normal values and agree with those observed in a chloro-derivative of the same structure (Ray et al., 1998). The cycloheptane ring adopts a half-chair conformation with a twofold axis through the C10 atom and bisecting the C17—C18 bond.

This is confirmed by its puckering parameters (Cremer & Pople, 1975) Q₂ = 1.032 (2) Å, ϕ₂ = 65.4 (1)°, Q₃ = 0.122 (2) Å, ϕ₃ = 324.4 (9)° and Q_T = 1.039 (2) Å. In the quinoline ring, the C2—C3, C4—C5 and C7—C8 bond distances are slightly shorter due to their localized double-bond character, while the N1—C5 bond shows partial double-bond character (Allen et al., 1987). The quinoline and benzene rings are essentially planar to within ±0.007 (2) Å and to within ±0.005 (2) Å, respectively, while atom F1 deviates slightly from the quinoline plane by -0.018 (1) Å. The quinoline and benzene ring planes make a dihedral angle of 46.3 (1)°.

S2. Experimental

The treatment of Vilsmeir-Haack reagent (phosphoryl chloride/dimethylformamide) with benzosuberone produced the β-chlorovinylaldehyde as an oil. This product was treated with p-fluoroaniline (freshly distilled) to afford the corresponding anil derivative as red solids. After heating the anil derivative at 503–513 K for 5 min, the title compound, (I), was obtained. Single crystals suitable for X-ray structure determination were obtained by slow evaporation from a chloroform–petroleum ether solution.

S3. Refinement

After checking their presence in the difference map, all H atoms were geometrically fixed and allowed to ride on their attached atoms.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 1997); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL, PARST (Nardelli, 1995) and PLATON (Spek, 1990).

Figures

Fig. 1. The structure of title compound showing 50% probability displacement ellipsoids with the atom-numbering scheme.

10-fluoro-6,7-dihydro-5H-benzo[6,7]cyclohepta[1,2-b]quinoline

Crystal data

C18H14FN	F(000) = 552
Mr = 263.30	Dx = 1.288 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.4871 (2) Å	Cell parameters from 4222 reflections
b = 10.0561 (2) Å	θ = 2.4–28.3°
c = 16.0181 (1) Å	µ = 0.08 mm^−1
β = 96.536 (1)°	T = 293 K
V = 1358.21 (4) Å^3	Block, colourless
Z = 4	0.48 × 0.44 × 0.28 mm

Data collection

Siemens SMART CCD area-detector diffractometer	1784 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.071
Graphite monochromator	θmax = 28.3°, θmin = 2.4°
Detector resolution: 8.33 pixels mm^-1	h = −6→11
ω scans	k = −13→10
9310 measured reflections	l = −19→20
3305 independent reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.054	H-atom parameters constrained
wR(F^2) = 0.148	w = 1/[σ^2(Fo^2) + (0.0688P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.90	(Δ/σ)max < 0.001
3305 reflections	Δρmax = 0.28 e Å^−3
182 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.046 (4)

Special details

Experimental. The data collection covered over a hemisphere of reciprocal space by a combination of three sets of exposures; each set had a different ϕ angle (0, 88 and 180°) for the crystal and each exposure of 10 s covered 0.3° in ω. The crystal-to-detector distance was 4 cm and the detector swing angle was -35°. Crystal decay was monitored by repeating fifty initial frames at the end of data collection and analysing the intensity of duplicate reflections, and was found to be negligible.

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 wRand 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. andis not relevant to the choice of reflections for refinement. R-factorsbased on F² are statistically about twice as large as those based on F, andR– 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	0.43909 (15)	0.30774 (14)	0.08522 (8)	0.0431 (4)
F1	−0.05440 (16)	0.64353 (14)	0.12711 (9)	0.1028 (5)
C1	0.31395 (18)	0.38900 (17)	0.09694 (10)	0.0415 (4)
C2	0.2918 (2)	0.50699 (19)	0.04944 (11)	0.0529 (5)
H2A	0.3610	0.5276	0.0103	0.064*
C3	0.1703 (2)	0.5908 (2)	0.06039 (13)	0.0623 (5)
H3A	0.1563	0.6690	0.0294	0.075*
C4	0.0676 (2)	0.5579 (2)	0.11849 (13)	0.0633 (6)
C5	0.0823 (2)	0.4478 (2)	0.16631 (12)	0.0599 (5)
H5A	0.0112	0.4303	0.2050	0.072*
C6	0.20792 (18)	0.35916 (18)	0.15651 (10)	0.0434 (4)
C7	0.23437 (19)	0.24116 (18)	0.20343 (10)	0.0488 (4)
H7A	0.1669	0.2190	0.2431	0.059*
C8	0.35752 (18)	0.15893 (18)	0.19145 (10)	0.0448 (4)
C9	0.3929 (2)	0.0348 (2)	0.24297 (11)	0.0581 (5)
H9A	0.3300	0.0359	0.2899	0.070*
H9B	0.5037	0.0358	0.2658	0.070*
C10	0.3588 (2)	−0.0935 (2)	0.19359 (12)	0.0633 (6)
H10A	0.2453	−0.1091	0.1864	0.076*
H10B	0.4084	−0.1671	0.2258	0.076*
C11	0.4192 (2)	−0.09067 (19)	0.10699 (11)	0.0546 (5)
H11A	0.4251	−0.1812	0.0867	0.066*
H11B	0.3429	−0.0433	0.0682	0.066*
C12	0.5794 (2)	−0.02609 (18)	0.10638 (10)	0.0459 (4)
C13	0.7114 (2)	−0.1009 (2)	0.09205 (11)	0.0565 (5)
H13A	0.7012	−0.1924	0.0849	0.068*
C14	0.8571 (2)	−0.0420 (2)	0.08821 (12)	0.0637 (6)
H14A	0.9443	−0.0939	0.0793	0.076*
C15	0.8736 (2)	0.0940 (2)	0.09765 (12)	0.0612 (6)
H15A	0.9717	0.1339	0.0949	0.073*
C16	0.7436 (2)	0.1707 (2)	0.11124 (11)	0.0524 (5)
H16A	0.7546	0.2623	0.1173	0.063*
C17	0.59613 (18)	0.11180 (18)	0.11594 (10)	0.0436 (4)
C18	0.45825 (17)	0.19700 (17)	0.12975 (9)	0.0406 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0447 (8)	0.0424 (9)	0.0433 (8)	−0.0014 (6)	0.0100 (6)	0.0003 (6)
F1	0.1134 (11)	0.0875 (11)	0.1180 (11)	0.0544 (8)	0.0588 (9)	0.0191 (8)
C1	0.0422 (9)	0.0425 (10)	0.0404 (9)	−0.0014 (7)	0.0065 (7)	−0.0038 (7)
C2	0.0567 (11)	0.0495 (12)	0.0555 (11)	0.0034 (8)	0.0189 (8)	0.0040 (9)
C3	0.0727 (13)	0.0471 (12)	0.0703 (13)	0.0107 (9)	0.0221 (10)	0.0055 (9)
C4	0.0693 (13)	0.0565 (14)	0.0682 (13)	0.0229 (10)	0.0253 (10)	−0.0016 (10)
C5	0.0595 (12)	0.0668 (15)	0.0577 (12)	0.0097 (9)	0.0258 (9)	0.0008 (10)
C6	0.0441 (9)	0.0461 (11)	0.0412 (9)	−0.0010 (7)	0.0101 (7)	−0.0042 (7)
C7	0.0501 (10)	0.0594 (12)	0.0389 (9)	−0.0046 (8)	0.0137 (7)	0.0026 (8)
C8	0.0469 (10)	0.0524 (11)	0.0349 (8)	−0.0026 (8)	0.0036 (7)	0.0014 (7)
C9	0.0615 (12)	0.0689 (14)	0.0446 (10)	0.0080 (10)	0.0085 (8)	0.0185 (9)
C10	0.0665 (12)	0.0562 (13)	0.0676 (13)	0.0016 (9)	0.0097 (10)	0.0257 (10)
C11	0.0596 (11)	0.0447 (11)	0.0576 (11)	−0.0024 (8)	−0.0017 (9)	0.0050 (8)
C12	0.0519 (11)	0.0483 (11)	0.0361 (9)	0.0063 (8)	−0.0010 (7)	0.0064 (7)
C13	0.0683 (12)	0.0496 (12)	0.0507 (11)	0.0153 (9)	0.0032 (9)	0.0054 (8)
C14	0.0555 (12)	0.0746 (16)	0.0610 (13)	0.0232 (10)	0.0065 (9)	0.0056 (11)
C15	0.0429 (10)	0.0796 (16)	0.0608 (12)	0.0039 (9)	0.0045 (9)	0.0002 (10)
C16	0.0501 (11)	0.0566 (12)	0.0504 (11)	−0.0027 (8)	0.0055 (8)	−0.0024 (8)
C17	0.0442 (9)	0.0496 (11)	0.0364 (9)	0.0033 (7)	0.0015 (7)	0.0008 (7)
C18	0.0391 (9)	0.0462 (11)	0.0360 (8)	−0.0024 (7)	0.0026 (7)	−0.0014 (7)

Geometric parameters (Å, º)

N1—C18	1.323 (2)	C9—H9B	0.9700
N1—C1	1.370 (2)	C10—C11	1.533 (3)
F1—C4	1.366 (2)	C10—H10A	0.9700
C1—C2	1.411 (2)	C10—H10B	0.9700
C1—C6	1.416 (2)	C11—C12	1.508 (2)
C2—C3	1.358 (3)	C11—H11A	0.9700
C2—H2A	0.9300	C11—H11B	0.9700
C3—C4	1.385 (3)	C12—C13	1.389 (2)
C3—H3A	0.9300	C12—C17	1.400 (2)
C4—C5	1.344 (3)	C13—C14	1.379 (3)
C5—C6	1.412 (2)	C13—H13A	0.9300
C5—H5A	0.9300	C14—C15	1.381 (3)
C6—C7	1.409 (2)	C14—H14A	0.9300
C7—C8	1.363 (2)	C15—C16	1.384 (2)
C7—H7A	0.9300	C15—H15A	0.9300
C8—C18	1.431 (2)	C16—C17	1.394 (2)
C8—C9	1.507 (2)	C16—H16A	0.9300
C9—C10	1.524 (3)	C17—C18	1.487 (2)
C9—H9A	0.9700
C18—N1—C1	118.55 (13)	C9—C10—H10A	109.0
N1—C1—C2	119.06 (14)	C11—C10—H10A	109.0
N1—C1—C6	121.87 (15)	C9—C10—H10B	109.0
C2—C1—C6	119.06 (15)	C11—C10—H10B	109.0
C3—C2—C1	120.58 (16)	H10A—C10—H10B	107.8
C3—C2—H2A	119.7	C12—C11—C10	114.12 (15)
C1—C2—H2A	119.7	C12—C11—H11A	108.7
C2—C3—C4	118.89 (19)	C10—C11—H11A	108.7
C2—C3—H3A	120.6	C12—C11—H11B	108.7
C4—C3—H3A	120.6	C10—C11—H11B	108.7
C5—C4—F1	118.93 (16)	H11A—C11—H11B	107.6
C5—C4—C3	123.73 (17)	C13—C12—C17	118.71 (16)
F1—C4—C3	117.34 (18)	C13—C12—C11	120.82 (18)
C4—C5—C6	118.59 (16)	C17—C12—C11	120.39 (15)
C4—C5—H5A	120.7	C14—C13—C12	121.26 (19)
C6—C5—H5A	120.7	C14—C13—H13A	119.4
C7—C6—C5	123.28 (15)	C12—C13—H13A	119.4
C7—C6—C1	117.58 (15)	C13—C14—C15	120.03 (17)
C5—C6—C1	119.14 (16)	C13—C14—H14A	120.0
C8—C7—C6	120.92 (14)	C15—C14—H14A	120.0
C8—C7—H7A	119.5	C14—C15—C16	119.75 (17)
C6—C7—H7A	119.5	C14—C15—H15A	120.1
C7—C8—C18	117.58 (16)	C16—C15—H15A	120.1
C7—C8—C9	122.21 (15)	C15—C16—C17	120.58 (18)
C18—C8—C9	120.16 (15)	C15—C16—H16A	119.7
C8—C9—C10	113.76 (14)	C17—C16—H16A	119.7
C8—C9—H9A	108.8	C16—C17—C12	119.66 (15)
C10—C9—H9A	108.8	C16—C17—C18	119.32 (16)
C8—C9—H9B	108.8	C12—C17—C18	121.01 (14)
C10—C9—H9B	108.8	N1—C18—C8	123.47 (14)
H9A—C9—H9B	107.7	N1—C18—C17	117.09 (13)
C9—C10—C11	112.99 (15)	C8—C18—C17	119.40 (15)
C18—N1—C1—C2	−179.63 (15)	C10—C11—C12—C13	111.62 (18)
C18—N1—C1—C6	1.6 (2)	C10—C11—C12—C17	−71.7 (2)
N1—C1—C2—C3	−179.02 (17)	C17—C12—C13—C14	0.8 (2)
C6—C1—C2—C3	−0.2 (3)	C11—C12—C13—C14	177.52 (16)
C1—C2—C3—C4	−0.6 (3)	C12—C13—C14—C15	−0.8 (3)
C2—C3—C4—C5	1.1 (3)	C13—C14—C15—C16	0.2 (3)
C2—C3—C4—F1	−179.18 (19)	C14—C15—C16—C17	0.3 (3)
F1—C4—C5—C6	179.46 (17)	C15—C16—C17—C12	−0.3 (2)
C3—C4—C5—C6	−0.8 (3)	C15—C16—C17—C18	−179.40 (16)
C4—C5—C6—C7	179.89 (18)	C13—C12—C17—C16	−0.2 (2)
C4—C5—C6—C1	0.0 (3)	C11—C12—C17—C16	−176.97 (14)
N1—C1—C6—C7	−0.6 (2)	C13—C12—C17—C18	178.82 (14)
C2—C1—C6—C7	−179.42 (16)	C11—C12—C17—C18	2.1 (2)
N1—C1—C6—C5	179.26 (15)	C1—N1—C18—C8	−1.8 (2)
C2—C1—C6—C5	0.5 (2)	C1—N1—C18—C17	−179.48 (13)
C5—C6—C7—C8	179.95 (17)	C7—C8—C18—N1	1.0 (2)
C1—C6—C7—C8	−0.2 (2)	C9—C8—C18—N1	−176.58 (15)
C6—C7—C8—C18	0.0 (2)	C7—C8—C18—C17	178.66 (15)
C6—C7—C8—C9	177.53 (16)	C9—C8—C18—C17	1.1 (2)
C7—C8—C9—C10	110.31 (19)	C16—C17—C18—N1	44.5 (2)
C18—C8—C9—C10	−72.2 (2)	C12—C17—C18—N1	−134.56 (16)
C8—C9—C10—C11	44.4 (2)	C16—C17—C18—C8	−133.33 (17)
C9—C10—C11—C12	40.5 (2)	C12—C17—C18—C8	47.6 (2)