3,12-Dimeth­oxy-5,6,9,10-tetra­hydro-[5]helicene-7,8-dicarbo­nitrile

Sahasithiwat, S.; Sooksimuang, T.; Kamtonwong, S.; Parnchan, W.; Kangkaew, L.

doi:10.1107/S1600536814014950

organic compounds

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ISSN: 2056-9890

Volume 70| Part 8| August 2014| Page o837

doi:10.1107/S1600536814014950

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3,12-Dimethoxy-5,6,9,10-tetrahydro-[5]helicene-7,8-dicarbonitrile

Somboon Sahasithiwat,^a ^* Thanasat Sooksimuang,^a Siriporn Kamtonwong,^a Waraporn Parnchan ^a and Laongdao Kangkaew ^a

^aNational Metal and Materials Technology Center (MTEC), 114 Thailand Science Park, Paholyothin Rd, Klong Luang, Pathumthani 12120, Thailand
^*Correspondence e-mail: somboons@mtec.or.th

(Received 27 May 2014; accepted 25 June 2014; online 2 July 2014)

The complete molecule of the title compound, C₂₆H₂₀N₂O₂, is generated by a crystallographic twofold axis. The torsion angle between the terminal and central benzene rings is −32.5 (2)°. The torsion angle along the inner helical rim of the molecule is −18.8 (2)° with each other. The C⋯C distance between the terminal rings is 3.016 (2) Å. In the crystal, weak C—H⋯N hydrogen bonds are observed.

Keywords: crystal structure.

CCDC reference: 1010118

Related literature

For the application of a pentahelicene derivative as an emitter in an organic light-emitting diode, see: Sahasithiwat et al. (2010 ). For related structures, see: McIntosh et al. (1954 ); Wang et al. (1997 ); Stammel et al. (1999 ); Ogawa et al. (2003 ); Rajapakse et al. (2011 ). For the synthesis of the title compound, see: Mandal et al. (2006 ). For general information and applications of helicenes, see: Shen & Chen (2012 ); Gingras (2013 ).

Experimental

Crystal data

C₂₆H₂₀N₂O₂
M_r = 392.44
Monoclinic, C 2/c
a = 17.9533 (7) Å
b = 13.5533 (7) Å
c = 8.1417 (4) Å
β = 95.785 (2)°
V = 1971.00 (16) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.67 × 0.44 × 0.26 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2012 ) T_min = 0.70, T_max = 0.75
10904 measured reflections
2204 independent reflections
1674 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.137
S = 1.07
2204 reflections
136 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1⋯N1ⁱ	0.93	2.79	3.466 (2)	131
C4—H4⋯N1ⁱⁱ	0.93	2.86	3.742 (2)	160
Symmetry codes: (i) -x, -y, -z; (ii) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2008 ); cell refinement: SAINT (Bruker, 2013 ); data reduction: SAINT; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ) and Mercury (Macrae et al., 2006 ); software used to prepare material for publication: WinGX (Farrugia, 2012) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1010118

Crystal structure: contains datablock I. DOI: 10.1107/S1600536814014950/nr2052sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814014950/nr2052Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814014950/nr2052Isup3.mol

checkCIF report

Comment top

Helicenes are polycyclic aromatic hydrocarbons (PAHs) that consist of ortho-fused aromatic rings arranged in helical chiraliry. Applications of helicenes are ranging from catalyst to molecular machines. (Shen et al., 2012; Gingras, 2013). The title compound is a derivative of pentahelicene in which two electron donor and two electron acceptor groups are added into the structure in order to improve its fluorescence quantum yield. Moreover, two rings connected to the central benzene ring are not fully aromatized and in a twist conformation. An application of a similar compound as an emitter for a light-emitting diode was reported (Sahasithiwat et al., 2010).

The geometric parameters of the title molecule agree well with reported similar structures (McIntosh et al., 1954; Wang et al., 1997; Stammel et al., 1999; Rajapakse et al., 2011). Half a molecule of the title compound belongs to asymmetric unit and a molecule is completed by the crystallographic twofold axis as shown in Figure 1. The dihedral angles [C1—C8—C10—C10ⁱ and C1ⁱ—C8ⁱ—C10ⁱ—C10] between a terminal and a central benzene ring are -32.5 (2)°. The two non-fully aromatized rings make a dihedral angle [C8—C10—C10ⁱ—C8ⁱ] of -18.8 (2)° with each other. The distance of the terminal rings as defined by C1···C1ⁱ distance of 3.016 (2)Å is causing by steric repultion of hydrogens on these carbons.

The crystal packing as shown in Figure 2 reveals that the molecules are linked through a network of weak C—H···N [C1—H1···N1(-x,-y,-z)] intermolecular interaction yielding racemic columns. Moreover, the other weak C—H···N [C4—H4···N1(-x+1/2,y,-z+1/2)] intermolecular interactions resulted in holding the columns together as exhibited in Figure 3.

Experimental top

A mixture of 6,6'-dimethoxy-3,4,3',4'-tetrahydro[1,1']binaphthalenyl (9.761 g, 30.7 mmol) and fumaronitrile (3.594 g, 46.0 mmol) was stirred and heated at 110 °C under argon atmosphere for 12 h. The resulting mixture was purified by column chromatography (SiO₂, 7734, 3:2 CH₂Cl₂-hexane, 1.8 L) to give a yellow foam of pure Diels-Alder adduct (6.673 g, 55% yield, mp. 139-141 °C). The Diels-Alder product (6.535 g, 16.6 mmol), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone(8.280 g, 36.5 mmol) and xylene (120 ml) was stirred and refluxed for 6 h. The mixture was cooled to room temperature and filtered off. Filtrate was evaporated to give crude product which was purified by column chromatography (SiO₂, 7734, toluene, 1.2 L) to give a yellow solid product (3.934 g, 61% yield, mp. 263-264 °C). This compound was characterized by FTIR, ¹H-NMR, and ¹³C-NMR. Crystals of the title compound suitable for X-ray analysis was obtained by slow evaporation of a chloroform-hexane solution.

Refinement top

All hydrogen atoms were placed in calculated positions and treated as riding atoms with C—H distances of 0.93 Å,0.97 Å, and 0.96 Å for aryl, methylene, and methyl H atoms, respectively. The H atoms were assigned Uiso = 1.2 Ueq(C) for aryl H, Uiso = 1.2 Ueq(C) for methylene H, and Uiso = 1.5 Ueq(C) for methyl H.

Related literature top

For the application of a pentahelicene derivative as an emitter in an organic light-emitting diode, see: Sahasithiwat et al. (2010). For related structures, see: McIntosh et al. (1954); Wang et al. (1997); Stammel et al. (1999); Ogawa et al. (2003); Rajapakse et al. (2011). For the synthesis of the title compound, see: Mandal et al. (2006). For general information and applications of helicenes, see: Shen & Chen (2012); Gingras (2013).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 2012) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound showing 50% probability displacement ellipsoids for non-H atoms. Symmetry code: (i) -x,y,1/2 - z.
	Fig. 2. Packing diagram of the title compound projected down the b axis showing hydrogen bonds as dashed lines.
	Fig. 3. Packing diagram of the title compound projected down the c axis showing hydrogen bonds as dashed lines.

3,12-Dimethoxy-5,6,9,10-tetrahydro-[5]helicene-7,8-dicarbonitrile top

Crystal data top

C₂₆H₂₀N₂O₂	F(000) = 824
M_r = 392.44	D_x = 1.322 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 17.9533 (7) Å	Cell parameters from 3787 reflections
b = 13.5533 (7) Å	θ = 2.3–27.1°
c = 8.1417 (4) Å	µ = 0.08 mm⁻¹
β = 95.785 (2)°	T = 296 K
V = 1971.00 (16) Å³	Block, green
Z = 4	0.67 × 0.44 × 0.26 mm

Data collection top

Bruker APEXII CCD diffractometer	1674 reflections with I > 2σ(I)
Radiation source: sealed tube	R_int = 0.025
ϕ and ω scans	θ_max = 27.3°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2012)	h = −23→21
T_min = 0.70, T_max = 0.75	k = −17→17
10904 measured reflections	l = −10→10
2204 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.042	H-atom parameters constrained
wR(F²) = 0.137	w = 1/[σ²(F_o²) + (0.0693P)² + 0.772P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
2204 reflections	Δρ_max = 0.18 e Å⁻³
136 parameters	Δρ_min = −0.19 e Å⁻³

Crystal data top

C₂₆H₂₀N₂O₂	V = 1971.00 (16) Å³
M_r = 392.44	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 17.9533 (7) Å	µ = 0.08 mm⁻¹
b = 13.5533 (7) Å	T = 296 K
c = 8.1417 (4) Å	0.67 × 0.44 × 0.26 mm
β = 95.785 (2)°

Data collection top

Bruker APEXII CCD diffractometer	2204 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2012)	1674 reflections with I > 2σ(I)
T_min = 0.70, T_max = 0.75	R_int = 0.025
10904 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.137	H-atom parameters constrained
S = 1.07	Δρ_max = 0.18 e Å⁻³
2204 reflections	Δρ_min = −0.19 e Å⁻³
136 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C4	0.18794 (7)	0.30146 (11)	0.13412 (18)	0.0409 (3)
H4	0.2399	0.3047	0.1479	0.049*
C10	0.03622 (7)	0.12362 (10)	0.22237 (18)	0.0374 (3)
C2	0.06956 (8)	0.37374 (11)	0.03575 (19)	0.0419 (4)
H2	0.0421	0.4247	−0.0174	0.050*
C8	0.07336 (7)	0.21339 (10)	0.16691 (17)	0.0370 (3)
O1	0.18785 (6)	0.46083 (8)	0.02479 (16)	0.0572 (3)
C9	0.15209 (7)	0.21797 (10)	0.18425 (17)	0.0382 (3)
C1	0.03382 (7)	0.29099 (10)	0.08781 (18)	0.0399 (3)
H1	−0.0181	0.2870	0.0695	0.048*
C6	0.15632 (8)	0.03662 (11)	0.1795 (2)	0.0465 (4)
H6A	0.1598	0.0358	0.0613	0.056*
H6B	0.1819	−0.0213	0.2269	0.056*
C7	0.03793 (8)	−0.05492 (10)	0.23454 (19)	0.0416 (4)
C3	0.14727 (8)	0.38012 (10)	0.06373 (18)	0.0416 (4)
C11	0.07496 (7)	0.03379 (10)	0.21240 (19)	0.0401 (3)
C5	0.19390 (7)	0.12912 (11)	0.2542 (2)	0.0465 (4)
H5A	0.1937	0.1280	0.3733	0.056*
H5B	0.2455	0.1318	0.2287	0.056*
C13	0.07734 (8)	−0.14666 (11)	0.2179 (2)	0.0476 (4)
N1	0.11026 (8)	−0.21725 (10)	0.2016 (2)	0.0659 (5)
C12	0.14758 (12)	0.54725 (14)	−0.0283 (3)	0.0749 (6)
H12A	0.1822	0.5981	−0.0518	0.112*
H12B	0.1184	0.5692	0.0572	0.112*
H12C	0.1150	0.5328	−0.1262	0.112*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C4	0.0256 (6)	0.0491 (8)	0.0494 (8)	−0.0029 (6)	0.0100 (6)	−0.0070 (6)
C10	0.0260 (6)	0.0394 (7)	0.0466 (8)	−0.0002 (5)	0.0033 (5)	−0.0005 (6)
C2	0.0353 (7)	0.0443 (8)	0.0465 (8)	0.0021 (6)	0.0060 (6)	0.0025 (6)
C8	0.0259 (6)	0.0396 (7)	0.0460 (8)	0.0002 (5)	0.0068 (5)	−0.0018 (6)
O1	0.0440 (6)	0.0520 (7)	0.0778 (8)	−0.0107 (5)	0.0166 (6)	0.0084 (6)
C9	0.0268 (6)	0.0440 (8)	0.0446 (8)	0.0016 (5)	0.0068 (5)	−0.0044 (6)
C1	0.0266 (6)	0.0443 (7)	0.0489 (8)	0.0001 (6)	0.0043 (6)	−0.0007 (6)
C6	0.0294 (7)	0.0446 (8)	0.0664 (10)	0.0074 (6)	0.0086 (7)	−0.0007 (7)
C7	0.0345 (7)	0.0388 (7)	0.0507 (9)	0.0031 (6)	−0.0002 (6)	−0.0011 (6)
C3	0.0370 (7)	0.0448 (8)	0.0447 (8)	−0.0063 (6)	0.0128 (6)	−0.0021 (6)
C11	0.0284 (7)	0.0420 (8)	0.0497 (8)	0.0032 (5)	0.0028 (6)	−0.0007 (6)
C5	0.0251 (6)	0.0520 (9)	0.0623 (10)	0.0043 (6)	0.0043 (6)	0.0005 (7)
C13	0.0370 (8)	0.0427 (8)	0.0618 (10)	0.0005 (6)	−0.0008 (7)	−0.0022 (7)
N1	0.0529 (9)	0.0487 (8)	0.0946 (12)	0.0102 (7)	−0.0004 (8)	−0.0082 (8)
C12	0.0666 (12)	0.0661 (12)	0.0881 (15)	−0.0194 (9)	−0.0103 (10)	0.0366 (11)

Geometric parameters (Å, º) top

C4—C3	1.383 (2)	C1—H1	0.9300
C4—C9	1.3836 (19)	C6—C11	1.5120 (19)
C4—H4	0.9300	C6—C5	1.521 (2)
C10—C11	1.4085 (18)	C6—H6A	0.9700
C10—C10ⁱ	1.418 (3)	C6—H6B	0.9700
C10—C8	1.4796 (19)	C7—C11	1.3943 (19)
C2—C1	1.3798 (19)	C7—C7ⁱ	1.410 (3)
C2—C3	1.393 (2)	C7—C13	1.444 (2)
C2—H2	0.9300	C5—H5A	0.9700
C8—C1	1.3903 (19)	C5—H5B	0.9700
C8—C9	1.4076 (18)	C13—N1	1.1392 (19)
O1—C3	1.3692 (17)	C12—H12A	0.9600
O1—C12	1.421 (2)	C12—H12B	0.9600
C9—C5	1.5005 (19)	C12—H12C	0.9600

C3—C4—C9	120.71 (12)	H6A—C6—H6B	108.1
C3—C4—H4	119.6	C11—C7—C7ⁱ	120.32 (8)
C9—C4—H4	119.6	C11—C7—C13	119.08 (13)
C11—C10—C10ⁱ	119.48 (8)	C7ⁱ—C7—C13	120.54 (8)
C11—C10—C8	116.93 (12)	O1—C3—C4	116.15 (12)
C10ⁱ—C10—C8	123.54 (7)	O1—C3—C2	123.99 (14)
C1—C2—C3	119.29 (13)	C4—C3—C2	119.85 (13)
C1—C2—H2	120.4	C7—C11—C10	119.56 (12)
C3—C2—H2	120.4	C7—C11—C6	121.77 (12)
C1—C8—C9	118.28 (12)	C10—C11—C6	118.67 (12)
C1—C8—C10	122.59 (12)	C9—C5—C6	108.96 (12)
C9—C8—C10	118.98 (12)	C9—C5—H5A	109.9
C3—O1—C12	117.57 (12)	C6—C5—H5A	109.9
C4—C9—C8	119.92 (13)	C9—C5—H5B	109.9
C4—C9—C5	122.58 (12)	C6—C5—H5B	109.9
C8—C9—C5	117.49 (12)	H5A—C5—H5B	108.3
C2—C1—C8	121.71 (13)	N1—C13—C7	177.50 (18)
C2—C1—H1	119.1	O1—C12—H12A	109.5
C8—C1—H1	119.1	O1—C12—H12B	109.5
C11—C6—C5	110.32 (12)	H12A—C12—H12B	109.5
C11—C6—H6A	109.6	O1—C12—H12C	109.5
C5—C6—H6A	109.6	H12A—C12—H12C	109.5
C11—C6—H6B	109.6	H12B—C12—H12C	109.5
C5—C6—H6B	109.6

C11—C10—C8—C1	145.00 (15)	C9—C4—C3—C2	−3.0 (2)
C10ⁱ—C10—C8—C1	−32.5 (3)	C1—C2—C3—O1	−176.54 (14)
C11—C10—C8—C9	−30.49 (19)	C1—C2—C3—C4	3.8 (2)
C10ⁱ—C10—C8—C9	152.05 (18)	C7ⁱ—C7—C11—C10	0.5 (3)
C3—C4—C9—C8	−1.3 (2)	C13—C7—C11—C10	177.68 (15)
C3—C4—C9—C5	177.21 (14)	C7ⁱ—C7—C11—C6	179.84 (17)
C1—C8—C9—C4	4.7 (2)	C13—C7—C11—C6	−3.0 (2)
C10—C8—C9—C4	−179.60 (13)	C10ⁱ—C10—C11—C7	8.9 (3)
C1—C8—C9—C5	−173.89 (13)	C8—C10—C11—C7	−168.68 (14)
C10—C8—C9—C5	1.79 (19)	C10ⁱ—C10—C11—C6	−170.49 (16)
C3—C2—C1—C8	−0.3 (2)	C8—C10—C11—C6	11.9 (2)
C9—C8—C1—C2	−3.9 (2)	C5—C6—C11—C7	−147.72 (15)
C10—C8—C1—C2	−179.43 (13)	C5—C6—C11—C10	31.6 (2)
C12—O1—C3—C4	−172.31 (16)	C4—C9—C5—C6	−136.89 (14)
C12—O1—C3—C2	8.0 (2)	C8—C9—C5—C6	41.68 (18)
C9—C4—C3—O1	177.34 (13)	C11—C6—C5—C9	−57.20 (17)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···N1ⁱⁱ	0.93	2.79	3.466 (2)	131
C4—H4···N1ⁱⁱⁱ	0.93	2.86	3.742 (2)	160

Symmetry codes: (ii) −x, −y, −z; (iii) −x+1/2, y+1/2, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···N1ⁱ	0.93	2.79	3.466 (2)	130.7
C4—H4···N1ⁱⁱ	0.93	2.86	3.742 (2)	159.6

Symmetry codes: (i) −x, −y, −z; (ii) −x+1/2, y+1/2, −z+1/2.

Acknowledgements

This research was supported by the National Metal and Materials Technology Center, MTEC, (grant No. MT-B-55-POL-07-523-I).

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