2,3:9,10-Dibenzotri­cyclo­[5.3.0.04,8]­deca-2,5,9-triene-6,7-dicarbo­nitrile

Jones, P.G.; Bubenitschek, P.; Hopf, H.; Witulski, B.

doi:10.1107/S160053680300134X

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2,3:9,10-Dibenzotricyclo[5.3.0.0^4,8]deca-2,5,9-triene-6,7-dicarbonitrile

P. G. Jones, P. Bubenitschek, H. Hopf and B. Witulski

In the title compound, C₂₀H₁₂N₂, the fused ring system leads to angle strain (e.g. sp³ angles of ca 98° or ca 130°). The molecules are linked by one C—H

N and two C—H

π interactions to form layers perpendicular to [10 $\overline 1$ ].

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S160053680300134X/bt6231sup1.cif Contains datablocks I, global
	Structure factor file (CIF format) https://doi.org/10.1107/S160053680300134X/bt6231Isup2.hkl Contains datablock I

CCDC reference: 204711

checkCIF report

Key indicators

Single-crystal X-ray study
T = 178 K
Mean (C-C) = 0.002 Å
R factor = 0.038
wR factor = 0.099
Data-to-parameter ratio = 13.0

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



PLAT_371  Alert C Long   C(sp2)-C(sp1) Bond  C(6)   -   C(19)  =       1.43 Ang.

PLAT_710  Alert C Delete 1-2-3 or 2-3-4 (CIF) Linear Torsion Angle #     65
                   C5  -C6  -C19 -N1    108.00  6.00   1.555   1.555   1.555   1.555

PLAT_710  Alert C Delete 1-2-3 or 2-3-4 (CIF) Linear Torsion Angle #     66
                   C7  -C6  -C19 -N1    -69.00  7.00   1.555   1.555   1.555   1.555

PLAT_710  Alert C Delete 1-2-3 or 2-3-4 (CIF) Linear Torsion Angle #     67
                   C6  -C7  -C20 -N2    -66.00  3.00   1.555   1.555   1.555   1.555

PLAT_710  Alert C Delete 1-2-3 or 2-3-4 (CIF) Linear Torsion Angle #     68
                   C8  -C7  -C20 -N2    178.00100.00   1.555   1.555   1.555   1.555

PLAT_710  Alert C Delete 1-2-3 or 2-3-4 (CIF) Linear Torsion Angle #     69
                   C1  -C7  -C20 -N2     68.00  3.00   1.555   1.555   1.555   1.555


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 6 Alert Level C = Please check

Comment top

Recently, we described the crystal structure of 9,10-dicyanodibenzoisobullvalene [(1); Jones et al., 2003]. Since the polycyclic carbon skeleton of (1) contains a vinylcyclopropane subunit, which, in principle, can undergo a ring-opening reaction, we decided to pyrolyze (1) (Witulski, 1992). We describe here the structure of the main isomerization product, (2).

The molecule of (2) is shown in Fig. 1. The strain imposed by the fused-ring system is apparent in, for example, the lengthened single bond C1—C7, the narrow sp² angles C4—C5—C6/C5—C6—C7 and sp³ angles C1—C7—C8/C4—C8—C7, and the widened sp³ angles C8—C9—C15/C1—C10—C18 (Table 1).

The molecules are linked to form ribbons parallel to the b axis by a weak C—H···N hydrogen bond (Table 2) and then, more strikingly, crosslinked by two C—H···π interactions to the centroid (cent) of the ring C2/C3/C11–C14, to form layers perpendicular to [101]; C5—H5···cent, with H···cent = 2.55 Å and C—H···cent = 153° for the operator 1 − x, y, 0.5 − z, and C16—H16···cent, with H···cent = 2.58 Å and C—H···cent = 155° for the operator 1.5 − x, 1.5 − y, −z. The C—H distances were normalized to 1.08 Å to calculate these values. The packing diagram is shown as Fig. 2.

Experimental top

A toluene solution of (1) was heated at 503 K for 24 h in a sealed ampoule, leading to two isomerization products in the ratio 9:1. These were separated by thick-layer chromatography and the major product [(2); 10% yield] was recrystallized from chloroform/pentane (Witulski, 1992).

Computing details top

Data collection: P3 (Nicolet, 1987); cell refinement: P3; data reduction: XDISK (Nicolet, 1987); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP (Siemens, 1996); software used to prepare material for publication: SHELXL97.

Figures top

	Fig. 1. The molecule of compound (2) in the crystal. The H atom at C1 is eclipsed. Ellipsoids are drawn at the 30% probability level and H-atom radii are arbitrary.
	Fig. 2. Packing diagram of compound (2). Hydrogen bonds of the type C—H···N are shown as thick dashed lines and C—H···π interactions as thin dashed lines. H atoms not involved in hydrogen bonds have been omitted. The view direction is perpendicular to [101], with the rings that accept the C—H···π interactions being viewed edge-on.

2,3:9,10-Dibenzotricyclo[5.3.0.0^4,8]deca-2,5,9-triene-6,7-dicarbonitrile top

Crystal data top

C₂₀H₁₂N₂	F(000) = 1168
M_r = 280.32	D_x = 1.272 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.834 (5) Å	Cell parameters from 50 reflections
b = 8.196 (3) Å	θ = 10–11.5°
c = 22.849 (7) Å	µ = 0.08 mm⁻¹
β = 99.11 (3)°	T = 178 K
V = 2927.8 (17) Å³	Prism, colourless
Z = 8	0.7 × 0.4 × 0.4 mm

Data collection top

Nicolet R3 diffractometer	R_int = 0.026
Radiation source: fine-focus sealed tube	θ_max = 25.1°, θ_min = 3.0°
Graphite monochromator	h = −18→18
ω scans	k = −9→1
2674 measured reflections	l = −27→0
2596 independent reflections	3 standard reflections every 147 reflections
1938 reflections with I > 2σ(I)	intensity decay: none

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)] = 0.038	H-atom parameters constrained
wR(F²) = 0.099	w = 1/[σ²(F_o²) + (0.0374P)² + 2.4161P] where P = (F_o² + 2F_c²)/3
S = 1.05	(Δ/σ)_max < 0.001
2596 reflections	Δρ_max = 0.18 e Å⁻³
200 parameters	Δρ_min = −0.17 e Å⁻³
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0026 (4)

Crystal data top

C₂₀H₁₂N₂	V = 2927.8 (17) Å³
M_r = 280.32	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 15.834 (5) Å	µ = 0.08 mm⁻¹
b = 8.196 (3) Å	T = 178 K
c = 22.849 (7) Å	0.7 × 0.4 × 0.4 mm
β = 99.11 (3)°

Data collection top

Nicolet R3 diffractometer	R_int = 0.026
2674 measured reflections	3 standard reflections every 147 reflections
2596 independent reflections	intensity decay: none
1938 reflections with I > 2σ(I)

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.099	H-atom parameters constrained
S = 1.05	Δρ_max = 0.18 e Å⁻³
2596 reflections	Δρ_min = −0.17 e Å⁻³
200 parameters

Special details top

Experimental. 9,10-Dicyano-dibenzoisobullvalene

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	0.62156 (10)	0.4401 (2)	0.37959 (7)	0.0289 (4)
H1	0.5901	0.3389	0.3876	0.035*
C2	0.56634 (10)	0.5927 (2)	0.37461 (7)	0.0283 (4)
C3	0.59356 (10)	0.7307 (2)	0.34623 (7)	0.0271 (4)
C4	0.66646 (10)	0.7094 (2)	0.31056 (7)	0.0288 (4)
H4	0.6948	0.8144	0.3027	0.035*
C5	0.62233 (11)	0.6265 (2)	0.25504 (7)	0.0305 (4)
H5	0.5987	0.6808	0.2195	0.037*
C6	0.62157 (10)	0.4659 (2)	0.26351 (7)	0.0296 (4)
C7	0.66999 (10)	0.4247 (2)	0.32454 (7)	0.0278 (4)
C8	0.73065 (10)	0.5747 (2)	0.33685 (7)	0.0285 (4)
H8	0.7809	0.5670	0.3154	0.034*
C9	0.75689 (10)	0.5694 (2)	0.40309 (7)	0.0293 (4)
C10	0.69658 (11)	0.4803 (2)	0.42803 (7)	0.0299 (4)
C11	0.49434 (11)	0.6034 (2)	0.40200 (7)	0.0320 (4)
H11	0.4751	0.5101	0.4208	0.038*
C12	0.45032 (11)	0.7503 (2)	0.40203 (7)	0.0349 (4)
H12	0.4015	0.7575	0.4213	0.042*
C13	0.47727 (11)	0.8854 (2)	0.37419 (7)	0.0349 (4)
H13	0.4470	0.9854	0.3743	0.042*
C14	0.54855 (11)	0.8754 (2)	0.34606 (7)	0.0309 (4)
H14	0.5666	0.9685	0.3266	0.037*
C15	0.82791 (11)	0.6344 (2)	0.43847 (8)	0.0357 (4)
H15	0.8684	0.6974	0.4217	0.043*
C16	0.83880 (13)	0.6055 (2)	0.49907 (8)	0.0422 (5)
H16	0.8874	0.6485	0.5240	0.051*
C17	0.77980 (13)	0.5150 (2)	0.52326 (8)	0.0447 (5)
H17	0.7889	0.4948	0.5647	0.054*
C18	0.70698 (12)	0.4524 (2)	0.48829 (8)	0.0381 (4)
H18	0.6657	0.3924	0.5054	0.046*
C19	0.58425 (11)	0.3468 (2)	0.22176 (8)	0.0350 (4)
C20	0.71256 (11)	0.2655 (2)	0.32669 (7)	0.0313 (4)
N1	0.55640 (11)	0.2497 (2)	0.18800 (8)	0.0510 (5)
N2	0.74157 (10)	0.1374 (2)	0.32778 (7)	0.0424 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0314 (9)	0.0267 (9)	0.0301 (9)	0.0004 (7)	0.0096 (7)	0.0014 (7)
C2	0.0298 (9)	0.0297 (9)	0.0256 (8)	0.0005 (7)	0.0052 (7)	−0.0022 (7)
C3	0.0284 (8)	0.0292 (9)	0.0237 (8)	−0.0014 (7)	0.0039 (6)	−0.0022 (7)
C4	0.0309 (9)	0.0285 (9)	0.0283 (8)	−0.0018 (7)	0.0084 (7)	0.0016 (7)
C5	0.0310 (9)	0.0377 (10)	0.0238 (8)	0.0011 (8)	0.0077 (7)	0.0008 (7)
C6	0.0272 (9)	0.0357 (10)	0.0266 (8)	−0.0004 (7)	0.0065 (7)	−0.0038 (7)
C7	0.0272 (9)	0.0300 (9)	0.0267 (8)	0.0011 (7)	0.0058 (7)	−0.0022 (7)
C8	0.0256 (8)	0.0310 (9)	0.0297 (9)	−0.0004 (7)	0.0072 (7)	−0.0024 (7)
C9	0.0297 (9)	0.0295 (9)	0.0288 (9)	0.0055 (7)	0.0048 (7)	−0.0021 (7)
C10	0.0352 (9)	0.0274 (9)	0.0271 (8)	0.0055 (7)	0.0056 (7)	0.0000 (7)
C11	0.0308 (9)	0.0351 (10)	0.0314 (9)	−0.0017 (7)	0.0096 (7)	0.0011 (7)
C12	0.0305 (9)	0.0424 (11)	0.0329 (9)	0.0047 (8)	0.0084 (7)	−0.0011 (8)
C13	0.0346 (10)	0.0357 (10)	0.0341 (10)	0.0070 (8)	0.0048 (8)	−0.0027 (8)
C14	0.0347 (9)	0.0303 (9)	0.0270 (9)	−0.0001 (8)	0.0032 (7)	0.0003 (7)
C15	0.0334 (9)	0.0353 (10)	0.0371 (10)	0.0034 (8)	0.0021 (8)	−0.0074 (8)
C16	0.0428 (11)	0.0450 (12)	0.0351 (10)	0.0085 (9)	−0.0055 (8)	−0.0073 (9)
C17	0.0583 (13)	0.0455 (12)	0.0276 (9)	0.0122 (10)	−0.0019 (9)	−0.0008 (8)
C18	0.0476 (11)	0.0346 (10)	0.0331 (10)	0.0079 (9)	0.0091 (8)	0.0047 (8)
C19	0.0324 (9)	0.0383 (10)	0.0339 (10)	0.0041 (8)	0.0036 (8)	−0.0053 (8)
C20	0.0298 (9)	0.0345 (10)	0.0307 (9)	−0.0016 (8)	0.0084 (7)	−0.0030 (8)
N1	0.0527 (11)	0.0486 (10)	0.0487 (10)	0.0023 (9)	−0.0009 (8)	−0.0153 (9)
N2	0.0442 (9)	0.0359 (9)	0.0498 (10)	0.0050 (8)	0.0159 (8)	−0.0010 (8)

Geometric parameters (Å, º) top

C1—C2	1.520 (2)	C9—C15	1.383 (2)
C1—C10	1.526 (2)	C9—C10	1.394 (2)
C1—C7	1.578 (2)	C10—C18	1.380 (2)
C1—H1	1.0000	C11—C12	1.391 (2)
C2—C11	1.387 (2)	C11—H11	0.9500
C2—C3	1.405 (2)	C12—C13	1.378 (2)
C3—C14	1.383 (2)	C12—H12	0.9500
C3—C4	1.525 (2)	C13—C14	1.387 (2)
C4—C5	1.509 (2)	C13—H13	0.9500
C4—C8	1.555 (2)	C14—H14	0.9500
C4—H4	1.0000	C15—C16	1.388 (3)
C5—C6	1.331 (2)	C15—H15	0.9500
C5—H5	0.9500	C16—C17	1.375 (3)
C6—C19	1.426 (2)	C16—H16	0.9500
C6—C7	1.519 (2)	C17—C18	1.393 (3)
C7—C20	1.466 (2)	C17—H17	0.9500
C7—C8	1.558 (2)	C18—H18	0.9500
C8—C9	1.506 (2)	C19—N1	1.147 (2)
C8—H8	1.0000	C20—N2	1.144 (2)

C2—C1—C10	104.45 (13)	C4—C8—H8	112.1
C2—C1—C7	110.65 (13)	C7—C8—H8	112.1
C10—C1—C7	100.06 (13)	C15—C9—C10	120.60 (16)
C2—C1—H1	113.5	C15—C9—C8	130.24 (16)
C10—C1—H1	113.5	C10—C9—C8	109.15 (14)
C7—C1—H1	113.5	C18—C10—C9	120.89 (16)
C11—C2—C3	119.44 (15)	C18—C10—C1	130.13 (16)
C11—C2—C1	121.48 (15)	C9—C10—C1	108.76 (14)
C3—C2—C1	118.82 (14)	C2—C11—C12	120.14 (16)
C14—C3—C2	119.73 (15)	C2—C11—H11	119.9
C14—C3—C4	122.01 (15)	C12—C11—H11	119.9
C2—C3—C4	117.90 (14)	C13—C12—C11	120.22 (16)
C5—C4—C3	102.23 (13)	C13—C12—H12	119.9
C5—C4—C8	101.09 (13)	C11—C12—H12	119.9
C3—C4—C8	112.25 (13)	C12—C13—C14	120.05 (16)
C5—C4—H4	113.4	C12—C13—H13	120.0
C3—C4—H4	113.4	C14—C13—H13	120.0
C8—C4—H4	113.4	C3—C14—C13	120.41 (16)
C6—C5—C4	109.66 (15)	C3—C14—H14	119.8
C6—C5—H5	125.2	C13—C14—H14	119.8
C4—C5—H5	125.2	C9—C15—C16	118.57 (18)
C5—C6—C19	126.30 (16)	C9—C15—H15	120.7
C5—C6—C7	109.81 (15)	C16—C15—H15	120.7
C19—C6—C7	123.86 (15)	C17—C16—C15	120.53 (18)
C20—C7—C6	113.04 (14)	C17—C16—H16	119.7
C20—C7—C8	115.43 (14)	C15—C16—H16	119.7
C6—C7—C8	101.37 (13)	C16—C17—C18	121.41 (17)
C20—C7—C1	108.87 (13)	C16—C17—H17	119.3
C6—C7—C1	118.38 (13)	C18—C17—H17	119.3
C8—C7—C1	98.99 (13)	C10—C18—C17	117.97 (18)
C9—C8—C4	117.90 (13)	C10—C18—H18	121.0
C9—C8—C7	102.89 (13)	C17—C18—H18	121.0
C4—C8—C7	98.28 (13)	N1—C19—C6	178.15 (19)
C9—C8—H8	112.1	N2—C20—C7	176.35 (18)

C10—C1—C2—C11	−99.04 (18)	C20—C7—C8—C4	162.38 (14)
C7—C1—C2—C11	154.11 (15)	C6—C7—C8—C4	39.86 (14)
C10—C1—C2—C3	75.00 (18)	C1—C7—C8—C4	−81.65 (13)
C7—C1—C2—C3	−31.9 (2)	C4—C8—C9—C15	−96.1 (2)
C11—C2—C3—C14	0.2 (2)	C7—C8—C9—C15	157.18 (17)
C1—C2—C3—C14	−173.99 (14)	C4—C8—C9—C10	85.08 (18)
C11—C2—C3—C4	−173.04 (15)	C7—C8—C9—C10	−21.67 (17)
C1—C2—C3—C4	12.8 (2)	C15—C9—C10—C18	−1.1 (3)
C14—C3—C4—C5	−97.02 (18)	C8—C9—C10—C18	177.90 (15)
C2—C3—C4—C5	76.03 (17)	C15—C9—C10—C1	174.09 (15)
C14—C3—C4—C8	155.44 (15)	C8—C9—C10—C1	−6.93 (18)
C2—C3—C4—C8	−31.5 (2)	C2—C1—C10—C18	92.0 (2)
C3—C4—C5—C6	−86.22 (16)	C7—C1—C10—C18	−153.41 (18)
C8—C4—C5—C6	29.71 (17)	C2—C1—C10—C9	−82.55 (16)
C4—C5—C6—C19	178.75 (15)	C7—C1—C10—C9	32.01 (17)
C4—C5—C6—C7	−3.36 (19)	C3—C2—C11—C12	−0.9 (2)
C5—C6—C7—C20	−148.48 (15)	C1—C2—C11—C12	173.08 (15)
C19—C6—C7—C20	29.5 (2)	C2—C11—C12—C13	0.9 (3)
C5—C6—C7—C8	−24.32 (17)	C11—C12—C13—C14	−0.1 (3)
C19—C6—C7—C8	153.62 (15)	C2—C3—C14—C13	0.6 (2)
C5—C6—C7—C1	82.52 (19)	C4—C3—C14—C13	173.54 (15)
C19—C6—C7—C1	−99.53 (19)	C12—C13—C14—C3	−0.7 (2)
C2—C1—C7—C20	−172.02 (13)	C10—C9—C15—C16	1.5 (3)
C10—C1—C7—C20	78.24 (15)	C8—C9—C15—C16	−177.21 (16)
C2—C1—C7—C6	−41.1 (2)	C9—C15—C16—C17	−0.4 (3)
C10—C1—C7—C6	−150.85 (14)	C15—C16—C17—C18	−1.2 (3)
C2—C1—C7—C8	67.08 (15)	C9—C10—C18—C17	−0.5 (3)
C10—C1—C7—C8	−42.65 (14)	C1—C10—C18—C17	−174.51 (17)
C5—C4—C8—C9	−151.13 (14)	C16—C17—C18—C10	1.6 (3)
C3—C4—C8—C9	−42.87 (19)	C5—C6—C19—N1	108 (6)
C5—C4—C8—C7	−41.74 (14)	C7—C6—C19—N1	−69 (7)
C3—C4—C8—C7	66.53 (15)	C6—C7—C20—N2	−66 (3)
C20—C7—C8—C9	−76.39 (16)	C8—C7—C20—N2	178 (100)
C6—C7—C8—C9	161.08 (12)	C1—C7—C20—N2	68 (3)
C1—C7—C8—C9	39.57 (15)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···N1ⁱ	0.95	2.59	3.314 (3)	134

Symmetry code: (i) −x+1, y+1, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₂₀H₁₂N₂
M_r	280.32
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	178
a, b, c (Å)	15.834 (5), 8.196 (3), 22.849 (7)
β (°)	99.11 (3)
V (Å³)	2927.8 (17)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.7 × 0.4 × 0.4

Data collection
Diffractometer	Nicolet R3 diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	2674, 2596, 1938
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.596

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.099, 1.05
No. of reflections	2596
No. of parameters	200
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.17

Computer programs: P3 (Nicolet, 1987), P3, XDISK (Nicolet, 1987), SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), XP (Siemens, 1996), SHELXL97.

Selected geometric parameters (Å, º) top

C1—C7	1.578 (2)	C5—C6	1.331 (2)

C6—C5—C4	109.66 (15)	C4—C8—C7	98.28 (13)
C5—C6—C7	109.81 (15)	C15—C9—C8	130.24 (16)
C8—C7—C1	98.99 (13)	C18—C10—C1	130.13 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C13—H13···N1ⁱ	0.95	2.59	3.314 (3)	134

Symmetry code: (i) −x+1, y+1, −z+1/2.

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