organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2414-3146

2,2′-[(4-Bromo­phen­yl)methyl­ene]bis­­(1H-pyrrole)

aBio-Organic Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India, bInstitute of Materials Science, Darmstadt University of Technology, Alarich-Weiss-Strasse 2, D-64287 Darmstadt, Germany, and cInternational SOS Clinics, 167A Nam Ky Khoi Nghia Street, District-3, HoChiMinh City, Vietnam
*Correspondence e-mail: nguyendonhuquynh@yahoo.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 12 June 2016; accepted 21 June 2016; online 24 June 2016)

The title compound, C15H13BrN2, is a substituted methane derivative. Three H atoms of the methane mol­ecule have been substituted by means of two pyrrole rings and one 4-bromo­phenyl moiety. The two pyrrole rings are inclined to one another by 85.0 (3)°, and to the benzene ring by 71.4 (2) and 69.5 (2)°. In the crystal, mol­ecules are linked via N—H⋯π and C—H⋯π inter­actions, forming layers parallel to (101). The layers are linked by C—Br⋯π inter­actions, forming a three-dimensional structure.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Dipyrro­methanes, substituted dipyrro­methanes and meso-substituted dipyrro­methanes are the building blocks for the synthesis of porphyrins (Mukherjee et al., 2015[Mukherjee, S., Bauri, A. K., Banerjee, S. & Bhattacharya, S. (2015). ScienceJet, 100, 1-9.]), fluorescent laser dyes (Loudet & Burgess, 2007[Loudet, A. & Burgess, K. (2007). Chem. Rev. 107, 4891-4932.]) and fluoro­phores. They are also an important tool in a variety of imaging applications (Taki, 2013[Taki, M. (2013). Cadmium: From Toxicity to Essentiality, Vol. 11, Metal ions in Life Sciences, edited by A. Sigel, H. Sigel & R. K. O. Sigel, pp. 99-115. Berlin: Springer.]) and chemo-sensors (Nikola et al., 2008[Nikola, B., Marija, R. & Kata, M. (2008). US Patent No. WO2008114067A1.]). In general, they are synthesized by acid-catalysed condensation reaction of pyrrole or a substituted pyrrole and an aldehyde (Littler et al., 1999[Littler, B. J., Miller, M. A., Hung, C.-H., Wagner, R. W., O'Shea, D. F., Boyle, P. D. & Lindsey, J. S. (1999). J. Org. Chem. 64, 1391-1396.]). The crude product is purified to obtain the corresponding dipyrro­methane which is used as precursor (Lee & Hupp, 2010[Lee, C. Y. & Hupp, J. T. (2010). Langmuir, 26, 3760-3765.]) for syntheses of target host mol­ecules such as mol­ecular nanotweezers (Zhao et al. 2013[Zhao, H., Liao, J., Yang, D., Xie, Y., Xu, Y., Wang, H. & Wang, B. (2013). Aust. J. Chem. 66, 972-982.]), porphyrins and fluorescent dyes (Tram et al., 2009[Tram, K., Yan, H., Jenkins, H. A., Vassiliev, S. & Bruce, D. (2009). Dyes Pigments, 82, 392-395.]). These host mol­ecules are utilized as optoelectronic materials (Lee & Hupp, 2010[Lee, C. Y. & Hupp, J. T. (2010). Langmuir, 26, 3760-3765.]; Rio et al., 2009[Rio, Y., Sánchez-García, D., Seitz, W., Torres, T., Sessler, J. L. & Guldi, D. M. (2009). Chem. Eur. J. 15, 3956-3959.]) in optical photovoltaic (OPV) cells, as organic light-emitting diodes (OLED), and for the purpose of material separation in supra­molecular chemistry.

The title compound, Fig. 1[link], can be considered as a substituted methane derivative. Three H atoms of the methane mol­ecule have been substituted by means of two pyrrole rings and one 4-bromo­phenyl moiety. The two pyrrole rings, N1/C8–C11 and N2/C12–C15, are inclined to one another by 85.0 (3)°, and to the benzene ring, C2–C7, by 71.4 (2) and 69.5 (2) °, respectively.

[Figure 1]
Figure 1
A view of the mol­ecular structure of the title compound, showing the atom labelling and displacement ellipsoids drawn at the 50% probability level.

In the crystal, mol­ecules are linked via N—H⋯π and C—H⋯π inter­actions, forming layers parallel to (101), Table 1[link] and Fig. 2[link]. The layers are linked by C—Br⋯π inter­actions, forming a three-dimensional structure, Table 1[link] and Fig. 3[link].

Table 1
Hydrogen-bond geometry (Å, °)

Cg1, Cg2 and Cg3 are the centroids of the N1/C8–C11, N2/C12–C15 and C2–C7 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
N2—H2NCg1i 0.86 2.43 3.262 (4) 163
C6—H6⋯Cg1ii 0.93 2.89 3.656 (5) 141
C9—H9⋯Cg3iii 0.93 2.71 3.590 (5) 159
C14—H14⋯Cg3iv 0.93 2.79 3.564 (5) 142
C5—Br1⋯Cg2v 1.91 (1) 3.70 (1) 5.595 (4) 171 (1)
Symmetry codes: (i) x-1, y, z; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (iii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]; (iv) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]; (v) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].
[Figure 2]
Figure 2
The crystal packing of the title compound, viewed along the b axis, with the inter­molecular inter­actions shown as dashed lines (see Table 1[link]).
[Figure 3]
Figure 3
The crystal packing of the title compound, viewed along the a axis, with the inter­molecular inter­actions shown as dashed lines (see Table 1[link]).

A search of the Cambridge Structural Database (CSD, Version 5.37, last update February 2016; Groom et al., 2016[Groom, C. R., Bruno, I. J., Lightfoot, M. P. & Ward, S. C. (2016). Acta Cryst. B72, 171-179.]), found 19 hits for 5-phenyl­dipyrro­methanes. 5-Phenyl­dipyrro­methane itself (CSD refcode LAYIA; Littler et al., 1999[Littler, B. J., Miller, M. A., Hung, C.-H., Wagner, R. W., O'Shea, D. F., Boyle, P. D. & Lindsey, J. S. (1999). J. Org. Chem. 64, 1391-1396.]) has a very similar structural skeleton to the title mol­ecule: the two pyrrole rings are inclined to one another by 87.1 (1)°, and to the benzene ring by 71.6 (1) and 67.8 (1)°.

Synthesis and crystallization

A suspension of 4-bromo­benzaldehyde (3.24 g, 57.7 mmol) in pyrrole (100 ml, 1.44 mol) was placed in a 250 ml two-necked round-bottom flask equipped with an inter­nal thermometer and a water condenser in the reflux position. The solution was heated to 323 k, and then the heat source was removed and TFA (444 µL, 5.77 mmol) was added immediately. A sharp increase in the temperature of the solution was observed and the solution rapidly became clear and dark. After 5 min the reaction was quenched and the product was purified following the general procedure [distilled at 360 K (0.01 mm/Hg); recrystallized from ethyl acetate:hexane (1:4)] giving the desired product as colourless crystals (yield 3.48 g, 41%; m.p. 403 K). 1H NMR (200 MHz, CDCl3): δH 5.43 (s, 1H, H-1), 5.92 (s, 2H, βH, H-11 & H-15), 6.16 (dd, J = 2.7 & 5.6 Hz, 2H, βH, H-10 & H-14), 6.67 (dd, J = 2.6 & 4.2 Hz, 2H, αH, H-9 & H-13), 7.15 (d, J = 8.2 Hz, 2H, H-6 & H-4/Ar—H),7.48 (d, J = 8.2 Hz, 2H, H-3 & H-7/Ar—H), 7.81(brs, 2H, >NH).

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C15H13BrN2
Mr 301.18
Crystal system, space group Monoclinic, P21/n
Temperature (K) 299
a, b, c (Å) 5.8132 (8), 19.763 (2), 11.656 (1)
β (°) 96.85 (1)
V3) 1329.6 (3)
Z 4
Radiation type Mo Kα
μ (mm−1) 3.08
Crystal size (mm) 0.34 × 0.26 × 0.12
 
Data collection
Diffractometer Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector
Absorption correction Multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.])
Tmin, Tmax 0.421, 0.709
No. of measured, independent and observed [I > 2σ(I)] reflections 4326, 2289, 1685
Rint 0.039
(sin θ/λ)max−1) 0.602
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.063, 0.176, 1.20
No. of reflections 2289
No. of parameters 163
H-atom treatment H-atom parameters constrained
Δρmax, Δρmin (e Å−3) 0.59, −1.22
Computer programs: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]), CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]), SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]), SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Structural data


Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: CrysAlis CCD (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

2,2'-[(4-Bromophenyl)methylene]bis(1H-pyrrole) top
Crystal data top
C15H13BrN2F(000) = 608
Mr = 301.18Dx = 1.505 Mg m3
Monoclinic, P21/nMelting point: 403 K
Hall symbol: -P 2ynMo Kα radiation, λ = 0.71073 Å
a = 5.8132 (8) ÅCell parameters from 1789 reflections
b = 19.763 (2) Åθ = 2.7–27.8°
c = 11.656 (1) ŵ = 3.08 mm1
β = 96.85 (1)°T = 299 K
V = 1329.6 (3) Å3Prism, colourless
Z = 40.34 × 0.26 × 0.12 mm
Data collection top
Oxford Diffraction Xcalibur
diffractometer with a Sapphire CCD detector
2289 independent reflections
Radiation source: fine-focus sealed tube1685 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.039
Rotation method data acquisition using ω scans.θmax = 25.4°, θmin = 2.7°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
h = 75
Tmin = 0.421, Tmax = 0.709k = 2317
4326 measured reflectionsl = 1213
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)] = 0.063Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.176H-atom parameters constrained
S = 1.20 w = 1/[σ2(Fo2) + (0.1P)2]
where P = (Fo2 + 2Fc2)/3
2289 reflections(Δ/σ)max < 0.001
163 parametersΔρmax = 0.59 e Å3
0 restraintsΔρmin = 1.22 e Å3
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 > 2sigma(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
Br10.86594 (9)0.49826 (2)0.17591 (5)0.0642 (3)
N10.7634 (6)0.19396 (18)0.0868 (3)0.0443 (9)
H1N0.76800.23570.10700.053*
N20.1873 (6)0.14504 (19)0.1458 (3)0.0481 (9)
H2N0.09540.13830.08340.058*
C10.4652 (6)0.2148 (2)0.0487 (3)0.0355 (9)
H10.32730.22140.00740.043*
C20.5648 (6)0.28383 (19)0.0784 (3)0.0338 (9)
C30.4351 (7)0.3416 (2)0.0523 (4)0.0417 (10)
H30.28670.33730.01330.050*
C40.5182 (7)0.4049 (2)0.0820 (4)0.0432 (10)
H40.42700.44300.06420.052*
C50.7386 (7)0.41107 (19)0.1385 (3)0.0395 (10)
C60.8724 (6)0.3555 (2)0.1673 (4)0.0402 (10)
H61.01980.36030.20730.048*
C70.7871 (6)0.29211 (19)0.1364 (3)0.0364 (9)
H70.87940.25430.15450.044*
C80.6299 (7)0.1687 (2)0.0082 (3)0.0387 (9)
C90.8879 (8)0.1435 (3)0.1283 (4)0.0541 (12)
H90.99270.14810.18220.065*
C100.8336 (8)0.0863 (3)0.0785 (4)0.0620 (13)
H100.89270.04360.09140.074*
C110.6677 (7)0.1020 (2)0.0013 (4)0.0500 (11)
H110.59900.07160.04510.060*
C120.3867 (6)0.18121 (19)0.1531 (3)0.0351 (9)
C130.1542 (8)0.1208 (2)0.2525 (4)0.0555 (12)
H130.02960.09480.26980.067*
C140.3335 (8)0.1414 (2)0.3281 (4)0.0491 (11)
H140.35540.13220.40690.059*
C150.4810 (7)0.1791 (2)0.2662 (4)0.0478 (11)
H150.61940.19920.29680.057*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0775 (5)0.0397 (4)0.0728 (5)0.0020 (2)0.0020 (3)0.0044 (2)
N10.048 (2)0.059 (2)0.028 (2)0.0062 (17)0.0100 (16)0.0044 (16)
N20.039 (2)0.059 (2)0.045 (2)0.0109 (17)0.0019 (17)0.0040 (17)
C10.031 (2)0.049 (2)0.026 (2)0.0040 (17)0.0014 (16)0.0007 (17)
C20.033 (2)0.047 (2)0.022 (2)0.0015 (17)0.0055 (16)0.0024 (15)
C30.031 (2)0.065 (3)0.029 (2)0.0060 (19)0.0012 (18)0.0050 (19)
C40.041 (2)0.048 (3)0.040 (3)0.0109 (19)0.0034 (19)0.0049 (19)
C50.049 (2)0.038 (2)0.033 (2)0.0005 (18)0.0112 (19)0.0012 (17)
C60.038 (2)0.045 (3)0.037 (2)0.0014 (18)0.0002 (19)0.0006 (17)
C70.0279 (19)0.043 (2)0.038 (2)0.0034 (17)0.0009 (17)0.0046 (17)
C80.037 (2)0.053 (3)0.025 (2)0.0065 (19)0.0006 (16)0.0072 (18)
C90.049 (3)0.078 (4)0.036 (3)0.002 (2)0.005 (2)0.014 (2)
C100.065 (3)0.070 (4)0.051 (3)0.006 (3)0.004 (2)0.021 (2)
C110.049 (3)0.058 (3)0.043 (3)0.004 (2)0.007 (2)0.009 (2)
C120.031 (2)0.040 (2)0.035 (2)0.0054 (16)0.0081 (17)0.0051 (16)
C130.052 (3)0.055 (3)0.065 (3)0.003 (2)0.026 (2)0.012 (2)
C140.063 (3)0.051 (3)0.037 (3)0.001 (2)0.017 (2)0.0028 (19)
C150.046 (2)0.069 (3)0.029 (2)0.017 (2)0.0059 (19)0.006 (2)
Geometric parameters (Å, º) top
Br1—C51.905 (4)C5—C61.365 (5)
N1—C91.355 (6)C6—C71.379 (5)
N1—C81.364 (5)C6—H60.9300
N1—H1N0.8600C7—H70.9300
N2—C121.356 (5)C8—C111.336 (6)
N2—C131.368 (6)C9—C101.326 (7)
N2—H2N0.8600C9—H90.9300
C1—C121.505 (5)C10—C111.430 (6)
C1—C21.506 (5)C10—H100.9300
C1—C81.529 (6)C11—H110.9300
C1—H10.9800C12—C151.366 (5)
C2—C31.381 (5)C13—C141.344 (6)
C2—C71.395 (5)C13—H130.9300
C3—C41.372 (6)C14—C151.400 (5)
C3—H30.9300C14—H140.9300
C4—C51.374 (6)C15—H150.9300
C4—H40.9300
C9—N1—C8110.0 (4)C6—C7—C2121.1 (4)
C9—N1—H1N125.0C6—C7—H7119.4
C8—N1—H1N125.0C2—C7—H7119.4
C12—N2—C13109.8 (4)C11—C8—N1107.4 (4)
C12—N2—H2N125.1C11—C8—C1131.9 (4)
C13—N2—H2N125.1N1—C8—C1120.6 (4)
C12—C1—C2111.0 (3)C10—C9—N1107.8 (4)
C12—C1—C8110.7 (3)C10—C9—H9126.1
C2—C1—C8113.4 (3)N1—C9—H9126.1
C12—C1—H1107.1C9—C10—C11107.7 (4)
C2—C1—H1107.1C9—C10—H10126.2
C8—C1—H1107.1C11—C10—H10126.2
C3—C2—C7117.4 (4)C8—C11—C10107.2 (4)
C3—C2—C1120.8 (3)C8—C11—H11126.4
C7—C2—C1121.8 (3)C10—C11—H11126.4
C4—C3—C2122.1 (4)N2—C12—C15106.6 (4)
C4—C3—H3118.9N2—C12—C1121.4 (3)
C2—C3—H3118.9C15—C12—C1132.0 (3)
C3—C4—C5118.8 (4)C14—C13—N2107.9 (4)
C3—C4—H4120.6C14—C13—H13126.0
C5—C4—H4120.6N2—C13—H13126.0
C6—C5—C4121.2 (4)C13—C14—C15107.4 (4)
C6—C5—Br1118.5 (3)C13—C14—H14126.3
C4—C5—Br1120.3 (3)C15—C14—H14126.3
C5—C6—C7119.4 (4)C12—C15—C14108.3 (4)
C5—C6—H6120.3C12—C15—H15125.9
C7—C6—H6120.3C14—C15—H15125.9
C12—C1—C2—C3100.7 (4)C12—C1—C8—N1164.7 (3)
C8—C1—C2—C3133.9 (4)C2—C1—C8—N139.2 (5)
C12—C1—C2—C777.2 (4)C8—N1—C9—C100.8 (5)
C8—C1—C2—C748.1 (5)N1—C9—C10—C110.4 (6)
C7—C2—C3—C40.4 (5)N1—C8—C11—C100.6 (5)
C1—C2—C3—C4177.7 (4)C1—C8—C11—C10176.9 (4)
C2—C3—C4—C50.7 (6)C9—C10—C11—C80.1 (5)
C3—C4—C5—C61.4 (6)C13—N2—C12—C150.5 (5)
C3—C4—C5—Br1177.4 (3)C13—N2—C12—C1179.1 (4)
C4—C5—C6—C71.7 (6)C2—C1—C12—N2139.7 (4)
Br1—C5—C6—C7177.2 (3)C8—C1—C12—N293.5 (4)
C5—C6—C7—C21.3 (6)C2—C1—C12—C1539.8 (6)
C3—C2—C7—C60.7 (5)C8—C1—C12—C1587.0 (5)
C1—C2—C7—C6177.3 (3)C12—N2—C13—C140.3 (5)
C9—N1—C8—C110.8 (5)N2—C13—C14—C150.1 (5)
C9—N1—C8—C1177.7 (4)N2—C12—C15—C140.6 (5)
C12—C1—C8—C1119.3 (6)C1—C12—C15—C14179.0 (4)
C2—C1—C8—C11144.8 (4)C13—C14—C15—C120.4 (5)
Hydrogen-bond geometry (Å, º) top
Cg1, Cg2 and Cg3 are the centroids of the N1/C8–C11, N2/C12–C15 and C2–C7 rings, respectively.
D—H···AD—HH···AD···AD—H···A
N2—H2N···Cg1i0.862.433.262 (4)163
C6—H6···Cg1ii0.932.893.656 (5)141
C9—H9···Cg3iii0.932.713.590 (5)159
C14—H14···Cg3iv0.932.793.564 (5)142
C5—Br1···Cg2v1.91 (1)3.70 (1)5.595 (4)171 (1)
Symmetry codes: (i) x1, y, z; (ii) x+1/2, y+1/2, z+1/2; (iii) x+1/2, y+1/2, z1/2; (iv) x1/2, y+1/2, z+1/2; (v) x+3/2, y+1/2, z+1/2.
 

Acknowledgements

The authors thank Professor Dr Hartmut, FG Strukturforschung, Material-und Geowissenschaften, Technische Universit at Darmstadt, for his kind cooperation to record the XRD of the crystal, and for providing diffractometer time.

References

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