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ISSN: 2056-9890

4,5-Diphen­­oxy­benzene-1,2-dicarbo­nitrile

aFaculty of Science, Universiti Brunei Darussalam, Jalan Tungku Link BE 1410, Brunei Darussalam, bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and cChemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203 Jeddah, Saudi Arabia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 31 January 2012; accepted 31 January 2012; online 4 February 2012)

In the title compound, C20H12N2O2, the phenyl and benzene rings are mutually perpendicular, with the dihedral angle between the phenyl rings being 87.92 (16)° and those formed between the phenyl rings and the benzene rings being 73.68 (15) and 84.65 (15)°. Helical supra­molecular chains along [010], mediated by C—H⋯N inter­actions, are found in the crystal structure.

Related literature

For the use of functionalized phthalocyanines as dyes in photodynamic therapy and in dye-sensitized solar cells, see: Li et al. (2008[Li, H., Jensen, T. J., Fronczek, F. R. & Vicente, M. G. H. (2008). J. Med. Chem. 51, 502-511.]); Jiang et al. (2011[Jiang, X.-J., Yeung, S.-L., Lo, P.-C., Fong, W. P. & Ng, D. K. P. (2011). J. Med. Chem. 54, 320-330.]); Zhao et al. (2009[Zhao, Z., Cammidge, A. N. & Cook, M. J. (2009). Chem. Commun. pp. 7530-7532.]). For a related structure, see: Yu et al. (2010[Yu, L., Zhou, X., Yin, Y., Li, R. & Peng, T. (2010). Acta Cryst. E66, o2527.]). The present synthesis is based on earlier syntheses; see: Wohrle et al. (1993[Wohrle, D., Eskes, M., Shigehara, K. & Yamada, A. (1993). Synthesis, pp. 194-196.]); Li et al. (2008[Li, H., Jensen, T. J., Fronczek, F. R. & Vicente, M. G. H. (2008). J. Med. Chem. 51, 502-511.]).

[Scheme 1]

Experimental

Crystal data
  • C20H12N2O2

  • Mr = 312.32

  • Orthorhombic, P 21 21 21

  • a = 5.6543 (4) Å

  • b = 13.5163 (9) Å

  • c = 19.9498 (17) Å

  • V = 1524.7 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 100 K

  • 0.30 × 0.10 × 0.10 mm

Data collection
  • Agilent SuperNova Dual diffractometer with an Atlas detector

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010[Agilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.974, Tmax = 0.991

  • 4325 measured reflections

  • 2029 independent reflections

  • 1498 reflections with I > 2σ(I)

  • Rint = 0.052

Refinement
  • R[F2 > 2σ(F2)] = 0.054

  • wR(F2) = 0.118

  • S = 1.01

  • 2029 reflections

  • 217 parameters

  • H-atom parameters constrained

  • Δρmax = 0.26 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C13—H13⋯N1i 0.95 2.52 3.422 (4) 159
Symmetry code: (i) [-x+3, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis PRO (Agilent, 2010[Agilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

Substituted phthalonitriles are precursors for functionalized phthalocyanines used as dyes in, for example, photodynamic therapy (Li et al., 2008; Jiang et al., 2011) and dye-sensitized solar cells (Zhao et al., 2009). Our interest in the latter prompted the synthesis of the title compound, (I).

In (I), Fig. 1, both phenyl rings lie to one side of the benzene ring to which they are connected. The dihedral angles between the (C9–C14) and (C15–C20) rings is 87.92 (16)° indicating an almost orthogonal relationship. The (C9–C14) and (C15–C20) rings form a dihedral angle of 73.68 (15) and 84.65 (15)°, respectively with the (C1–C6) ring. The molecular conformation observed in (I) resembles closely that reported for the p-methoxy derivative (Yu et al., 2010).

The most prominent feature of the crystal packing is the formation of helical supramolecular chains along [010] that are mediated by C—H···N interactions, Table 1 and Fig. 2.

Related literature top

For the use of functionalized phthalocyanines as dyes in photodynamic therapy and in dye-sensitized solar cells, see: Li et al. (2008); Jiang et al. (2011); Zhao et al. (2009). For a related structure, see: Yu et al. (2010). The present synthesis is based on earlier syntheses; see: Wohrle et al. (1993); Li et al. (2008).

Experimental top

The title compound was prepared by modification of a literature procedures (Wohrle et al., 1993; Li et al., 2008). 4,5-Dichlorophthalonitrile (1.0 g, 5.0 mmol) and phenol (2.0 g, 21.3 mmol) were dissolved in DMF (20 ml) and heated to 353 K. Potassium carbonate (4.5 g, 32.6 mmol) was added in four portions with stirring over 20 minutes and the temperature maintained for a further three hours. The mixture was then cooled to room temperature and poured into ice-water (100 ml). The resulting precipitate was filtered and recrystallized from acetone / water to provide 0.47 g (35% yield) of colourless crystals, M. pt.: 432–436 K (lit. 422 K (Wohrle et al., 1993)). 1H NMR (400 MHz, CDCl3) δ 7.09 (4H, m), 7.16 (2H, s), 7.30 (2H, m), 7.47 (4H, m).

Refinement top

Carbon-bound H-atoms were placed in calculated positions [C—H = 0.95 Å, Uiso(H) = 1.2Ueq(C)] and were included in the refinement in the riding model approximation. In the absence of significant anomalous scattering effects, 1100 Friedel pairs were averaged in the final refinement.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular of (I) showing the atom-labelling scheme and displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. A view of the helical supramolecular chain along [010] in (I). The C—H···N contacts are shown as orange dashed lines.
4,5-Diphenoxybenzene-1,2-dicarbonitrile top
Crystal data top
C20H12N2O2F(000) = 648
Mr = 312.32Dx = 1.361 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 1267 reflections
a = 5.6543 (4) Åθ = 2.5–27.5°
b = 13.5163 (9) ŵ = 0.09 mm1
c = 19.9498 (17) ÅT = 100 K
V = 1524.7 (2) Å3Block, colourless
Z = 40.30 × 0.10 × 0.10 mm
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2029 independent reflections
Radiation source: SuperNova (Mo) X-ray Source1498 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.052
Detector resolution: 10.4041 pixels mm-1θmax = 27.6°, θmin = 2.5°
ω scanh = 77
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
k = 1716
Tmin = 0.974, Tmax = 0.991l = 2517
4325 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.054Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.118H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0522P)2]
where P = (Fo2 + 2Fc2)/3
2029 reflections(Δ/σ)max < 0.001
217 parametersΔρmax = 0.26 e Å3
0 restraintsΔρmin = 0.26 e Å3
Crystal data top
C20H12N2O2V = 1524.7 (2) Å3
Mr = 312.32Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 5.6543 (4) ŵ = 0.09 mm1
b = 13.5163 (9) ÅT = 100 K
c = 19.9498 (17) Å0.30 × 0.10 × 0.10 mm
Data collection top
Agilent SuperNova Dual
diffractometer with an Atlas detector
2029 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)
1498 reflections with I > 2σ(I)
Tmin = 0.974, Tmax = 0.991Rint = 0.052
4325 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0540 restraints
wR(F2) = 0.118H-atom parameters constrained
S = 1.01Δρmax = 0.26 e Å3
2029 reflectionsΔρmin = 0.26 e Å3
217 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
xyzUiso*/Ueq
O10.7480 (4)0.46056 (17)0.21758 (11)0.0246 (5)
O20.8019 (4)0.49051 (16)0.08401 (11)0.0237 (6)
N11.6503 (5)0.2459 (2)0.05129 (14)0.0276 (7)
N21.5732 (5)0.1975 (2)0.24912 (15)0.0302 (7)
C10.9365 (6)0.4161 (2)0.18642 (16)0.0205 (7)
C20.9635 (6)0.4325 (2)0.11812 (16)0.0191 (7)
C31.1429 (6)0.3878 (2)0.08308 (17)0.0217 (7)
H31.15820.39920.03630.026*
C41.3028 (6)0.3257 (2)0.11572 (16)0.0215 (8)
C51.2763 (6)0.3093 (2)0.18456 (16)0.0197 (7)
C61.0916 (6)0.3539 (2)0.21997 (17)0.0196 (7)
H61.07240.34170.26650.024*
C71.4946 (6)0.2810 (2)0.07954 (16)0.0218 (7)
C81.4418 (6)0.2465 (2)0.22039 (16)0.0220 (7)
C90.7792 (6)0.4909 (2)0.28421 (16)0.0210 (7)
C100.6053 (6)0.4644 (3)0.32990 (17)0.0262 (8)
H100.47600.42400.31680.031*
C110.6253 (6)0.4987 (3)0.39549 (17)0.0272 (8)
H110.50820.48130.42750.033*
C120.8137 (6)0.5579 (2)0.41466 (18)0.0288 (8)
H120.82540.58100.45950.035*
C130.9840 (6)0.5829 (2)0.36819 (17)0.0271 (8)
H131.11360.62330.38120.033*
C140.9673 (6)0.5493 (2)0.30229 (17)0.0248 (8)
H141.08480.56650.27030.030*
C150.8279 (5)0.5936 (2)0.08943 (16)0.0200 (7)
C161.0254 (6)0.6379 (2)0.11785 (16)0.0220 (8)
H161.14900.59890.13630.026*
C171.0384 (6)0.7406 (3)0.11868 (16)0.0244 (8)
H171.17260.77200.13780.029*
C180.8576 (6)0.7979 (2)0.09186 (16)0.0251 (8)
H180.86670.86810.09320.030*
C190.6632 (6)0.7514 (3)0.06305 (16)0.0253 (8)
H190.53970.79010.04410.030*
C200.6483 (6)0.6491 (2)0.06170 (16)0.0233 (8)
H200.51560.61760.04190.028*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0196 (12)0.0316 (12)0.0227 (12)0.0066 (12)0.0010 (10)0.0033 (10)
O20.0241 (14)0.0174 (10)0.0296 (13)0.0020 (10)0.0070 (11)0.0005 (10)
N10.0256 (16)0.0299 (15)0.0274 (16)0.0015 (15)0.0001 (14)0.0008 (14)
N20.0240 (16)0.0299 (15)0.0366 (18)0.0041 (15)0.0025 (15)0.0008 (14)
C10.0182 (16)0.0166 (14)0.0267 (19)0.0032 (15)0.0007 (15)0.0060 (14)
C20.0161 (16)0.0157 (15)0.0255 (18)0.0002 (14)0.0055 (14)0.0027 (13)
C30.0236 (17)0.0170 (14)0.0246 (19)0.0017 (14)0.0005 (16)0.0020 (14)
C40.0219 (19)0.0172 (16)0.0254 (19)0.0014 (15)0.0000 (15)0.0032 (14)
C50.0182 (16)0.0132 (13)0.0277 (18)0.0023 (14)0.0042 (15)0.0018 (14)
C60.0185 (17)0.0190 (15)0.0212 (17)0.0001 (15)0.0012 (14)0.0002 (14)
C70.0223 (18)0.0209 (16)0.0221 (18)0.0042 (16)0.0052 (16)0.0001 (14)
C80.0223 (17)0.0192 (15)0.0244 (18)0.0013 (16)0.0030 (15)0.0013 (15)
C90.0225 (17)0.0195 (15)0.0209 (17)0.0069 (15)0.0017 (15)0.0016 (14)
C100.0219 (18)0.0255 (16)0.031 (2)0.0013 (16)0.0011 (15)0.0034 (16)
C110.0280 (19)0.0240 (16)0.030 (2)0.0015 (17)0.0061 (16)0.0008 (16)
C120.035 (2)0.0262 (18)0.0253 (19)0.0079 (17)0.0027 (17)0.0064 (16)
C130.0254 (18)0.0221 (16)0.034 (2)0.0034 (16)0.0046 (17)0.0058 (15)
C140.0188 (16)0.0203 (16)0.035 (2)0.0042 (16)0.0042 (16)0.0031 (15)
C150.0190 (17)0.0199 (15)0.0211 (18)0.0016 (15)0.0027 (15)0.0010 (14)
C160.0185 (17)0.0266 (17)0.0209 (18)0.0024 (16)0.0008 (15)0.0003 (14)
C170.0206 (17)0.0314 (17)0.0212 (18)0.0053 (17)0.0007 (15)0.0061 (16)
C180.0245 (18)0.0219 (16)0.0289 (19)0.0027 (16)0.0057 (16)0.0005 (15)
C190.0246 (18)0.0263 (17)0.0250 (18)0.0078 (16)0.0004 (15)0.0026 (16)
C200.0172 (16)0.0293 (17)0.0232 (18)0.0014 (16)0.0004 (15)0.0002 (15)
Geometric parameters (Å, º) top
O1—C11.373 (4)C10—H100.9500
O1—C91.402 (4)C11—C121.386 (5)
O2—C21.383 (4)C11—H110.9500
O2—C151.405 (3)C12—C131.379 (5)
N1—C71.148 (4)C12—H120.9500
N2—C81.148 (4)C13—C141.394 (5)
C1—C61.387 (4)C13—H130.9500
C1—C21.389 (4)C14—H140.9500
C2—C31.372 (4)C15—C201.379 (4)
C3—C41.395 (4)C15—C161.388 (4)
C3—H30.9500C16—C171.390 (4)
C4—C51.399 (4)C16—H160.9500
C4—C71.436 (5)C17—C181.390 (5)
C5—C61.398 (5)C17—H170.9500
C5—C81.452 (5)C18—C191.391 (5)
C6—H60.9500C18—H180.9500
C9—C141.372 (5)C19—C201.385 (4)
C9—C101.388 (5)C19—H190.9500
C10—C111.393 (5)C20—H200.9500
C1—O1—C9117.4 (2)C12—C11—H11119.5
C2—O2—C15117.1 (2)C10—C11—H11119.5
O1—C1—C6122.5 (3)C13—C12—C11119.5 (3)
O1—C1—C2117.4 (3)C13—C12—H12120.2
C6—C1—C2120.1 (3)C11—C12—H12120.2
C3—C2—O2119.2 (3)C12—C13—C14120.4 (3)
C3—C2—C1120.7 (3)C12—C13—H13119.8
O2—C2—C1120.1 (3)C14—C13—H13119.8
C2—C3—C4120.4 (3)C9—C14—C13119.2 (3)
C2—C3—H3119.8C9—C14—H14120.4
C4—C3—H3119.8C13—C14—H14120.4
C3—C4—C5119.0 (3)C20—C15—C16121.4 (3)
C3—C4—C7120.5 (3)C20—C15—O2115.6 (3)
C5—C4—C7120.5 (3)C16—C15—O2122.9 (3)
C6—C5—C4120.5 (3)C15—C16—C17118.6 (3)
C6—C5—C8119.0 (3)C15—C16—H16120.7
C4—C5—C8120.5 (3)C17—C16—H16120.7
C1—C6—C5119.3 (3)C18—C17—C16120.9 (3)
C1—C6—H6120.3C18—C17—H17119.6
C5—C6—H6120.3C16—C17—H17119.6
N1—C7—C4178.9 (3)C17—C18—C19119.2 (3)
N2—C8—C5179.4 (4)C17—C18—H18120.4
C14—C9—C10121.7 (3)C19—C18—H18120.4
C14—C9—O1121.0 (3)C20—C19—C18120.5 (3)
C10—C9—O1117.2 (3)C20—C19—H19119.8
C9—C10—C11118.3 (3)C18—C19—H19119.8
C9—C10—H10120.9C15—C20—C19119.4 (3)
C11—C10—H10120.9C15—C20—H20120.3
C12—C11—C10120.9 (3)C19—C20—H20120.3
C9—O1—C1—C635.9 (4)C6—C5—C8—N255 (41)
C9—O1—C1—C2146.5 (3)C4—C5—C8—N2124 (41)
C15—O2—C2—C3103.2 (3)C1—O1—C9—C1452.0 (4)
C15—O2—C2—C180.0 (4)C1—O1—C9—C10131.6 (3)
O1—C1—C2—C3177.7 (3)C14—C9—C10—C110.1 (5)
C6—C1—C2—C30.0 (4)O1—C9—C10—C11176.3 (3)
O1—C1—C2—O21.0 (4)C9—C10—C11—C120.1 (5)
C6—C1—C2—O2176.7 (3)C10—C11—C12—C130.2 (5)
O2—C2—C3—C4177.4 (3)C11—C12—C13—C140.1 (5)
C1—C2—C3—C40.7 (5)C10—C9—C14—C130.1 (5)
C2—C3—C4—C50.5 (5)O1—C9—C14—C13176.1 (3)
C2—C3—C4—C7178.3 (3)C12—C13—C14—C90.0 (5)
C3—C4—C5—C60.4 (5)C2—O2—C15—C20172.5 (3)
C7—C4—C5—C6179.1 (3)C2—O2—C15—C1610.5 (4)
C3—C4—C5—C8179.0 (3)C20—C15—C16—C170.8 (5)
C7—C4—C5—C80.2 (5)O2—C15—C16—C17177.7 (3)
O1—C1—C6—C5178.4 (3)C15—C16—C17—C180.2 (5)
C2—C1—C6—C50.9 (4)C16—C17—C18—C190.9 (5)
C4—C5—C6—C11.1 (5)C17—C18—C19—C200.7 (5)
C8—C5—C6—C1178.3 (3)C16—C15—C20—C191.0 (5)
C3—C4—C7—N1123 (21)O2—C15—C20—C19178.1 (3)
C5—C4—C7—N156 (21)C18—C19—C20—C150.2 (5)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···N1i0.952.523.422 (4)159
Symmetry code: (i) x+3, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC20H12N2O2
Mr312.32
Crystal system, space groupOrthorhombic, P212121
Temperature (K)100
a, b, c (Å)5.6543 (4), 13.5163 (9), 19.9498 (17)
V3)1524.7 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.30 × 0.10 × 0.10
Data collection
DiffractometerAgilent SuperNova Dual
diffractometer with an Atlas detector
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.974, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
4325, 2029, 1498
Rint0.052
(sin θ/λ)max1)0.651
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.054, 0.118, 1.01
No. of reflections2029
No. of parameters217
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.26, 0.26

Computer programs: CrysAlis PRO (Agilent, 2010), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···N1i0.952.523.422 (4)159
Symmetry code: (i) x+3, y+1/2, z+1/2.
 

Footnotes

Additional correspondence author, e-mail: david.young@ubd.edu.bn.

Acknowledgements

We gratefully acknowledge funding from the Brunei Research Council, and thank the Ministry of Higher Education (Malaysia) for funding structural studies through the High-Impact Research scheme (UM.C/HIR/MOHE/SC/12).

References

First citationAgilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.
First citationBrandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals
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