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ISSN: 2056-9890

2,5-Di­hexyl-3,6-di­phenyl­pyrrolo­[3,4-c]pyrrole-1,4(2H,5H)-dione

aDepartment of Physics, Dokuz Eylül University, Tınaztepe 35160, Buca-Izmir, Turkey, bDepartment of Chemistry, Dokuz Eylül University, Tınaztepe 35160, Buca-Izmir, Turkey, and cDepartment of Physics, Ondokuz Mayıs University, Kurupelit-Samsun, Turkey
*Correspondence e-mail: muhittin.aygun@deu.edu.tr

(Received 7 May 2010; accepted 28 May 2010; online 5 June 2010)

The asymmetric unit of the title compound, C30H36N2O2, contains one half-mol­ecule, the other half being generated by a crystallographic inversion centre. The crystal structure is devoid of any classical hydrogen bonds however, non-classical C—H⋯O inter­actions link the mol­ecules into chains propagating in [001] and a C—H⋯π inter­action leads to the formation of a two-dimensional network in (011).

Related literature

For the use of diketodiphenyl­pyrrolo­pyrroles as pigmants, see: Iqbal et al. (1988[Iqbal, A., Jost, M., Kirchmayr, R., Pfenninger, J., Rochat, A. C. & Wallquist, O. (1988). Soc. Chim. Belg. 97, 615-643.]); Herbst & Hunger (1993[Herbst, W. & Hunger, K. (1993). Industrial Organic Pigments, 2nd ed., pp. 467-475. Weinheim: Wiley-VCH.]). For related structures, see; Hirota et al. (2006[Hirota, T., Imoda, T., Takahashi, H. & Mizuguchi, J. (2006). Acta Cryst. E62, o111-o113.]); Mizuguchi (1998[Mizuguchi, J. (1998). Acta Cryst. C54, 1482-1484.]). For the synthesis of the starting reactant, see: Morton et al. (2002[Morton, C. J. H., Gilmour, R., Smith, D. M., Lightfoot, P., Slawin, A. M. Z. & MacLean, E. J. (2002). Tetrahedron, 58, 5547-5565.]).

[Scheme 1]

Experimental

Crystal data
  • C30H36N2O2

  • Mr = 456.61

  • Monoclinic, P 21 /c

  • a = 13.4809 (11) Å

  • b = 5.5393 (3) Å

  • c = 17.4838 (14) Å

  • β = 90.218 (7)°

  • V = 1305.59 (17) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 293 K

  • 0.48 × 0.22 × 0.07 mm

Data collection
  • Stoe IPDS 2 diffractometer

  • Absorption correction: integration (North et al., 1968[North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359.]) Tmin = 0.963, Tmax = 0.989

  • 9230 measured reflections

  • 2989 independent reflections

  • 1604 reflections with I > 2σ(I)

  • Rint = 0.038

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.136

  • S = 0.86

  • 2989 reflections

  • 172 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.13 e Å−3

  • Δρmin = −0.12 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C1—H1⋯O2i 0.93 (2) 2.57 (2) 3.226 (2) 127.8 (17)
C3—H3⋯O2ii 0.98 (2) 2.43 (2) 3.316 (3) 149.6 (18)
Symmetry codes: (i) -x, -y+1, -z+1; (ii) [x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}].

Data collection: X-AREA (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie GmbH, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie GmbH, Darmstadt, Germany.]); 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: PLUTON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Diketodiphenylpyrrolopyrroles are industrially important red pigments (Herbst & Hunger, 1993). The success of these compounds as pigments relies, in part, on their high light fastness and very low solubility in most common solvents. This state of low solubility is presumed to result from the presence of a 2-dimensional network formed by intermolecular hydrogen bonds (C-H···O), combined with ππ and Van der Waals interactions of the aryl substituents between layers of molecules (Iqbal et al., 1988).

The molecular structure of the title molecule is illustrated in Fig. 1. It is situated on an inversion center. The pyrrolopyrrole 8-membered ring is almost planar (C8 has a maximum deviation of 0.4636 (15) Å). Because of the steric effect of the alkyl group, the pyrrolopyrrole and phenyl rings are not coplanar. The dihedral angle between the mean planes of these rings is 34.38 (9) °.

In the crystal molecules are linked into one dimensional chains, generated by two–folded screw operation along the c-axis of the unit cell, via weak C3-H3 ···O2ii interactions (Symmetry code: (ii) x,1/2-y, 1/2 +z]; Fig. 2 and Table 1]. There is also a C–H ··· π interaction in the crystal structure involving the phenyl ring (C1-C6; centroid Cg) and atom C2 in a neighbouring molecule [C2—H2 ··· Cgb: H2···Cgb = 2.90Å and C2—H2···Cgb = 129°; symmetry code: (b) - x, -1/2 + y, 3/2 - z]. This interaction forms a one dimensional chain running along the c-axis. These two interactions lead to the formation of a two-dimensional network in (011) [Fig. 3].

Related literature top

For the use of diketodiphenylpyrrolopyrroles as pigmants, see: Iqbal et al. (1988); Herbst & Hunger (1993). For related structures, see; Hirota et al. (2006); Mizuguchi (1998). For the synthesis of the starting reactant, see: Morton et al. (2002).

Experimental top

The starting reactant, 3,6-diphenyl-2,5-dihydro-1,4-diketopyrrolo[3,4-c]pyrrole-1,4-dione (L), was prepared following the literature procedure (Morton et al., 2002). The synthesis of the title compound was carried out under a nitrogen atmosphere. L (0.59 g, 0.00204 mol) was stirred in 1-methyl-2-pyrolidinone (30 mL) at room temperature. Potassium-tert-butoxide (0.230 g, 0.00816 mmol) was then added follwed by the addition of the n-hexyl bromide (0.340 g, 0.00204 mmol) and the mixture was stirred for 18 hours, after which it was poured into 30 mL of cold water. The precipitate formed was filtered off and the crude product purified by column chromatography, using ethyl acetate/n-hexane (1:3) as eluent. Re-crystallization from methanol produced orange prism-like crystals of the title compound, suitable for X-ray analysis. Yield: 44%; m.p. = 243°C; IR (KBr): ν=C—H (ger.) 3055, ν-C—H (ger.) 2847-2911, ν-C=O (ger.) 1674; 1H NMR (CDCl3) : δ (ppm) 3.74 (t, 2H); 1.59 (p, 2H); 1.24 (6H, m); 0.82 (t, 3H)

Refinement top

Aromatic H-atoms were located in difference Fourier maps and freeely refined. The others H-atoms were included in calculated positions and treated as riding atoms: C–H = 0.96 Å for methyl H-atoms and 0.97 Å for methylene H atoms, with Uiso(H) = k × Ueq(C), where k = 1.5 for methyl H-atosm and = 1.2 for methylene H-atoms.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLUTON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title compound, with displacement ellipsoids drawn at the 50% probability level. The unlabelled atoms are related by the inversion center (symmetry code = -x, 1-y, 1-z).
[Figure 2] Fig. 2. A view of the crystal packing of the title compound, illustrating the formation of the C-H···O hydrogen bonded chain propagating along the c-axis (H-atoms not involved in this interaction have been omited for clarity; Symmetry code: (ii) x,1/2-y,1/2+z).
[Figure 3] Fig. 3. A view of the crystal packing of the title compound, illustrating the C–H ··· O and C – H ··· π interactions which contributes to the formation of a two-dimensional network in (011). (hexyl groups and H-atoms not involved in this interaction have been omited for clarity; Symmetry codes: (ii) x,1/2-y,1/2+z, (b) -x,1/2+y,1/2-z).
2,5-Dihexyl-3,6-diphenylpyrrolo[3,4-c]pyrrole- 1,4(2H,5H)-dione top
Crystal data top
C30H36N2O2F(000) = 492
Mr = 456.61Dx = 1.161 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 6690 reflections
a = 13.4809 (11) Åθ = 1.5–29.6°
b = 5.5393 (3) ŵ = 0.07 mm1
c = 17.4838 (14) ÅT = 293 K
β = 90.218 (7)°Prism, orange
V = 1305.59 (17) Å30.48 × 0.22 × 0.07 mm
Z = 2
Data collection top
Stoe IPDS 2
diffractometer
2989 independent reflections
Radiation source: fine-focus sealed tube1604 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.038
Detector resolution: 6.67 pixels mm-1θmax = 27.5°, θmin = 1.5°
ω and ϕ scansh = 1717
Absorption correction: integration
(North et al., 1968)
k = 76
Tmin = 0.963, Tmax = 0.989l = 2219
9230 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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136H atoms treated by a mixture of independent and constrained refinement
S = 0.86 w = 1/[σ2(Fo2) + (0.0797P)2]
where P = (Fo2 + 2Fc2)/3
2989 reflections(Δ/σ)max < 0.001
172 parametersΔρmax = 0.13 e Å3
0 restraintsΔρmin = 0.12 e Å3
Crystal data top
C30H36N2O2V = 1305.59 (17) Å3
Mr = 456.61Z = 2
Monoclinic, P21/cMo Kα radiation
a = 13.4809 (11) ŵ = 0.07 mm1
b = 5.5393 (3) ÅT = 293 K
c = 17.4838 (14) Å0.48 × 0.22 × 0.07 mm
β = 90.218 (7)°
Data collection top
Stoe IPDS 2
diffractometer
2989 independent reflections
Absorption correction: integration
(North et al., 1968)
1604 reflections with I > 2σ(I)
Tmin = 0.963, Tmax = 0.989Rint = 0.038
9230 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.136H atoms treated by a mixture of independent and constrained refinement
S = 0.86Δρmax = 0.13 e Å3
2989 reflectionsΔρmin = 0.12 e Å3
172 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
xyzUiso*/Ueq
H10.0038 (15)0.043 (4)0.5980 (12)0.059 (6)*
H30.1434 (16)0.228 (4)0.7917 (14)0.081 (7)*
H50.2139 (14)0.396 (4)0.6811 (11)0.060 (6)*
H20.0192 (15)0.307 (4)0.6947 (12)0.066 (6)*
H40.2334 (15)0.128 (4)0.7809 (13)0.069 (6)*
O20.15927 (10)0.7876 (3)0.42882 (8)0.0616 (4)
N10.15436 (10)0.5041 (3)0.52594 (8)0.0455 (4)
C10.04698 (14)0.0115 (3)0.63284 (11)0.0481 (5)
C20.06082 (15)0.1683 (4)0.69339 (12)0.0550 (5)
C30.13127 (16)0.1198 (4)0.74799 (13)0.0593 (5)
C40.18816 (16)0.0862 (4)0.74268 (12)0.0596 (6)
C50.17535 (14)0.2435 (4)0.68207 (11)0.0525 (5)
C60.10474 (12)0.1964 (3)0.62547 (10)0.0435 (4)
C70.08382 (12)0.3606 (3)0.56225 (10)0.0425 (4)
C80.11058 (13)0.6500 (4)0.46795 (10)0.0470 (5)
C90.00613 (12)0.4115 (3)0.52888 (10)0.0441 (4)
C110.26221 (12)0.4958 (4)0.53304 (12)0.0500 (5)
H11A0.29090.48320.48240.060*
H11B0.28080.35240.56150.060*
C120.30505 (12)0.7163 (4)0.57300 (12)0.0540 (5)
H12A0.28890.85930.54340.065*
H12B0.27450.73280.62290.065*
C130.41624 (14)0.7009 (4)0.58286 (14)0.0643 (6)
H13A0.43180.56040.61380.077*
H13B0.44620.67770.53310.077*
C140.46184 (14)0.9206 (4)0.61985 (14)0.0679 (6)
H14A0.42970.94750.66870.081*
H14B0.44821.05980.58780.081*
C150.57231 (17)0.9048 (5)0.63300 (19)0.0942 (9)
H15A0.58600.76090.66280.113*
H15B0.60450.88530.58390.113*
C160.6173 (2)1.1131 (5)0.67233 (17)0.0936 (6)
H16A0.68731.08660.67830.140*
H16B0.58761.13220.72180.140*
H16C0.60651.25650.64260.140*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O20.0544 (8)0.0736 (10)0.0566 (8)0.0152 (7)0.0035 (6)0.0179 (8)
N10.0406 (7)0.0486 (9)0.0472 (8)0.0032 (7)0.0068 (6)0.0032 (7)
C10.0490 (10)0.0452 (11)0.0500 (11)0.0005 (8)0.0029 (8)0.0015 (9)
C20.0586 (12)0.0448 (12)0.0615 (13)0.0035 (9)0.0062 (9)0.0052 (10)
C30.0647 (12)0.0595 (13)0.0538 (12)0.0145 (10)0.0018 (10)0.0119 (11)
C40.0600 (12)0.0686 (14)0.0502 (12)0.0080 (10)0.0142 (10)0.0043 (11)
C50.0522 (10)0.0499 (12)0.0552 (12)0.0003 (9)0.0125 (9)0.0026 (10)
C60.0444 (9)0.0416 (10)0.0445 (10)0.0029 (7)0.0051 (7)0.0026 (8)
C70.0476 (9)0.0385 (10)0.0412 (9)0.0037 (7)0.0069 (7)0.0028 (8)
C80.0474 (9)0.0509 (11)0.0427 (10)0.0061 (8)0.0057 (8)0.0024 (9)
C90.0456 (9)0.0460 (10)0.0407 (9)0.0070 (8)0.0073 (7)0.0019 (8)
C110.0420 (9)0.0527 (11)0.0554 (11)0.0007 (8)0.0030 (8)0.0034 (10)
C120.0422 (10)0.0539 (12)0.0657 (13)0.0017 (8)0.0043 (8)0.0028 (10)
C130.0442 (10)0.0659 (14)0.0827 (15)0.0004 (9)0.0086 (10)0.0067 (12)
C140.0519 (11)0.0711 (14)0.0806 (15)0.0086 (10)0.0072 (10)0.0043 (13)
C150.0580 (13)0.094 (2)0.131 (2)0.0089 (13)0.0183 (14)0.0201 (19)
C160.0949 (17)0.0920.0940.0241 (15)0.0145 (15)0.0125 (17)
Geometric parameters (Å, º) top
O2—C81.218 (2)C9—C8i1.450 (2)
N1—C71.394 (2)C11—C121.520 (3)
N1—C81.423 (2)C11—H11A0.9700
N1—C111.459 (2)C11—H11B0.9700
C1—C21.382 (3)C12—C131.511 (3)
C1—C61.396 (3)C12—H12A0.9700
C1—H10.93 (2)C12—H12B0.9700
C2—C31.371 (3)C13—C141.508 (3)
C2—H20.95 (2)C13—H13A0.9700
C3—C41.378 (3)C13—H13B0.9700
C3—H30.99 (2)C14—C151.509 (3)
C4—C51.382 (3)C14—H14A0.9700
C4—H40.93 (2)C14—H14B0.9700
C5—C61.395 (3)C15—C161.473 (3)
C5—H50.99 (2)C15—H15A0.9700
C6—C71.458 (2)C15—H15B0.9700
C7—C91.373 (2)C16—H16A0.9600
C8—C9i1.450 (2)C16—H16B0.9600
C9—C9i1.418 (4)C16—H16C0.9600
C7—N1—C8111.50 (14)N1—C11—H11B109.0
C7—N1—C11128.63 (15)C12—C11—H11B109.0
C8—N1—C11119.27 (15)H11A—C11—H11B107.8
C2—C1—C6121.04 (19)C13—C12—C11112.49 (16)
C2—C1—H1118.7 (13)C13—C12—H12A109.1
C6—C1—H1120.2 (13)C11—C12—H12A109.1
C3—C2—C1120.1 (2)C13—C12—H12B109.1
C3—C2—H2123.2 (13)C11—C12—H12B109.1
C1—C2—H2116.7 (13)H12A—C12—H12B107.8
C2—C3—C4120.0 (2)C14—C13—C12113.97 (18)
C2—C3—H3122.2 (14)C14—C13—H13A108.8
C4—C3—H3117.8 (14)C12—C13—H13A108.8
C3—C4—C5120.37 (19)C14—C13—H13B108.8
C3—C4—H4121.3 (14)C12—C13—H13B108.8
C5—C4—H4118.2 (14)H13A—C13—H13B107.7
C4—C5—C6120.6 (2)C13—C14—C15114.8 (2)
C4—C5—H5119.1 (12)C13—C14—H14A108.6
C6—C5—H5120.1 (12)C15—C14—H14A108.6
C5—C6—C1117.88 (17)C13—C14—H14B108.6
C5—C6—C7123.43 (17)C15—C14—H14B108.6
C1—C6—C7118.55 (16)H14A—C14—H14B107.5
C9—C7—N1106.98 (15)C16—C15—C14115.5 (2)
C9—C7—C6128.20 (16)C16—C15—H15A108.4
N1—C7—C6124.79 (15)C14—C15—H15A108.4
O2—C8—N1122.19 (16)C16—C15—H15B108.4
O2—C8—C9i133.95 (17)C14—C15—H15B108.4
N1—C8—C9i103.87 (15)H15A—C15—H15B107.5
C7—C9—C9i109.86 (18)C15—C16—H16A109.5
C7—C9—C8i142.35 (17)C15—C16—H16B109.5
C9i—C9—C8i107.79 (18)H16A—C16—H16B109.5
N1—C11—C12113.00 (15)C15—C16—H16C109.5
N1—C11—H11A109.0H16A—C16—H16C109.5
C12—C11—H11A109.0H16B—C16—H16C109.5
C6—C1—C2—C30.8 (3)C1—C6—C7—N1149.42 (17)
C1—C2—C3—C40.3 (3)C7—N1—C8—O2179.45 (18)
C2—C3—C4—C50.7 (3)C11—N1—C8—O27.6 (3)
C3—C4—C5—C60.1 (3)C7—N1—C8—C9i0.6 (2)
C4—C5—C6—C10.9 (3)C11—N1—C8—C9i172.40 (15)
C4—C5—C6—C7176.70 (18)N1—C7—C9—C9i0.2 (2)
C2—C1—C6—C51.4 (3)C6—C7—C9—C9i177.71 (19)
C2—C1—C6—C7177.34 (18)N1—C7—C9—C8i179.4 (2)
C8—N1—C7—C90.3 (2)C6—C7—C9—C8i1.5 (4)
C11—N1—C7—C9171.14 (17)C7—N1—C11—C12111.5 (2)
C8—N1—C7—C6178.23 (17)C8—N1—C11—C1278.2 (2)
C11—N1—C7—C610.9 (3)N1—C11—C12—C13177.67 (17)
C5—C6—C7—C9142.7 (2)C11—C12—C13—C14177.97 (19)
C1—C6—C7—C933.0 (3)C12—C13—C14—C15177.7 (2)
C5—C6—C7—N134.9 (3)C13—C14—C15—C16177.3 (3)
Symmetry code: (i) x, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O2i0.93 (2)2.57 (2)3.226 (2)127.8 (17)
C3—H3···O2ii0.98 (2)2.43 (2)3.316 (3)149.6 (18)
Symmetry codes: (i) x, y+1, z+1; (ii) x, y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC30H36N2O2
Mr456.61
Crystal system, space groupMonoclinic, P21/c
Temperature (K)293
a, b, c (Å)13.4809 (11), 5.5393 (3), 17.4838 (14)
β (°) 90.218 (7)
V3)1305.59 (17)
Z2
Radiation typeMo Kα
µ (mm1)0.07
Crystal size (mm)0.48 × 0.22 × 0.07
Data collection
DiffractometerStoe IPDS 2
diffractometer
Absorption correctionIntegration
(North et al., 1968)
Tmin, Tmax0.963, 0.989
No. of measured, independent and
observed [I > 2σ(I)] reflections
9230, 2989, 1604
Rint0.038
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.136, 0.86
No. of reflections2989
No. of parameters172
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.13, 0.12

Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLUTON (Spek, 2009), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C1—H1···O2i0.93 (2)2.57 (2)3.226 (2)127.8 (17)
C3—H3···O2ii0.98 (2)2.43 (2)3.316 (3)149.6 (18)
Symmetry codes: (i) x, y+1, z+1; (ii) x, y+1/2, z+1/2.
 

Acknowledgements

The authors acknowledge the Dokuz E­ylül University Research Fund (project No. 2007.KB·FEN.036) for financial support of this work. In addition, RS thanks TÜBİTAK (The Scientific and Technical Research Council of Turkey) for partial financial support.

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