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

Bauri, A.K.; Foro, S.; Nguyen, N.D.Q.

doi:10.1107/S2414314616010051

organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 1| Part 6| June 2016| x161005

doi:10.1107/S2414314616010051

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

A. K. Bauri,^a Sabine Foro ^b and Nhu Do Quynh Nguyen ^c ^*

^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.

Keywords: crystal structure; 4-bromophenyl; dipyrromethane; C—H⋯π interactions; N—H⋯π interactions; C—Br⋯π interactions.

CCDC reference: 1486804

Structure description

Dipyrromethanes, substituted dipyrromethanes and meso-substituted dipyrromethanes are the building blocks for the synthesis of porphyrins (Mukherjee et al., 2015 ), fluorescent laser dyes (Loudet & Burgess, 2007 ) and fluorophores. They are also an important tool in a variety of imaging applications (Taki, 2013 ) and chemo-sensors (Nikola et al., 2008 ). In general, they are synthesized by acid-catalysed condensation reaction of pyrrole or a substituted pyrrole and an aldehyde (Littler et al., 1999 ). The crude product is purified to obtain the corresponding dipyrromethane which is used as precursor (Lee & Hupp, 2010 ) for syntheses of target host molecules such as molecular nanotweezers (Zhao et al. 2013 ), porphyrins and fluorescent dyes (Tram et al., 2009 ). These host molecules are utilized as optoelectronic materials (Lee & Hupp, 2010; Rio et al., 2009 ) 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, 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
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 and Fig. 2. The layers are linked by C—Br⋯π interactions, forming a three-dimensional structure, Table 1 and Fig. 3.

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	D⋯A	D—H⋯A
N2—H2N⋯Cg1ⁱ	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⋯Cg3^iv	0.93	2.79	3.564 (5)	142
C5—Br1⋯Cg2^v	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
The crystal packing of the title compound, viewed along the b axis, with the intermolecular interactions shown as dashed lines (see Table 1

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

A search of the Cambridge Structural Database (CSD, Version 5.37, last update February 2016; Groom et al., 2016 ), found 19 hits for 5-phenyldipyrromethanes. 5-Phenyldipyrromethane itself (CSD refcode LAYIA; Littler et al., 1999) 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): δ_H 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.

Table 2
Experimental details

Crystal data
Chemical formula	C₁₅H₁₃BrN₂
M_r	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)
V (Å³)	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 $[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, England.]$ )
T_min, T_max	0.421, 0.709
No. of measured, independent and observed [I > 2σ(I)] reflections	4326, 2289, 1685
R_int	0.039
(sin θ/λ)_max (Å⁻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
Δρ_max, Δρ_min (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 ), PLATON (Spek, 2009 ) and Mercury (Macrae et al., 2008 ), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Structural data

CCDC reference: 1486804

Crystal structure: contains datablocks I, global. DOI: 10.1107/S2414314616010051/su4054sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616010051/su4054Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616010051/su4054Isup3.cml

checkCIF report

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

C₁₅H₁₃BrN₂	F(000) = 608
M_r = 301.18	D_x = 1.505 Mg m⁻³
Monoclinic, P2₁/n	Melting point: 403 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 5.8132 (8) Å	Cell parameters from 1789 reflections
b = 19.763 (2) Å	θ = 2.7–27.8°
c = 11.656 (1) Å	µ = 3.08 mm⁻¹
β = 96.85 (1)°	T = 299 K
V = 1329.6 (3) Å³	Prism, colourless
Z = 4	0.34 × 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 tube	1685 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.039
Rotation method data acquisition using ω scans.	θ_max = 25.4°, θ_min = 2.7°
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009)	h = −7→5
T_min = 0.421, T_max = 0.709	k = −23→17
4326 measured reflections	l = −12→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.063	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.176	H-atom parameters constrained
S = 1.20	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
2289 reflections	(Δ/σ)_max < 0.001
163 parameters	Δρ_max = 0.59 e Å⁻³
0 restraints	Δρ_min = −1.22 e Å⁻³

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

	x	y	z	U_iso*/U_eq
Br1	0.86594 (9)	0.49826 (2)	0.17591 (5)	0.0642 (3)
N1	0.7634 (6)	0.19396 (18)	−0.0868 (3)	0.0443 (9)
H1N	0.7680	0.2357	−0.1070	0.053*
N2	0.1873 (6)	0.14504 (19)	0.1458 (3)	0.0481 (9)
H2N	0.0954	0.1383	0.0834	0.058*
C1	0.4652 (6)	0.2148 (2)	0.0487 (3)	0.0355 (9)
H1	0.3273	0.2214	−0.0074	0.043*
C2	0.5648 (6)	0.28383 (19)	0.0784 (3)	0.0338 (9)
C3	0.4351 (7)	0.3416 (2)	0.0523 (4)	0.0417 (10)
H3	0.2867	0.3373	0.0133	0.050*
C4	0.5182 (7)	0.4049 (2)	0.0820 (4)	0.0432 (10)
H4	0.4270	0.4430	0.0642	0.052*
C5	0.7386 (7)	0.41107 (19)	0.1385 (3)	0.0395 (10)
C6	0.8724 (6)	0.3555 (2)	0.1673 (4)	0.0402 (10)
H6	1.0198	0.3603	0.2073	0.048*
C7	0.7871 (6)	0.29211 (19)	0.1364 (3)	0.0364 (9)
H7	0.8794	0.2543	0.1545	0.044*
C8	0.6299 (7)	0.1687 (2)	−0.0082 (3)	0.0387 (9)
C9	0.8879 (8)	0.1435 (3)	−0.1283 (4)	0.0541 (12)
H9	0.9927	0.1481	−0.1822	0.065*
C10	0.8336 (8)	0.0863 (3)	−0.0785 (4)	0.0620 (13)
H10	0.8927	0.0436	−0.0914	0.074*
C11	0.6677 (7)	0.1020 (2)	−0.0013 (4)	0.0500 (11)
H11	0.5990	0.0716	0.0451	0.060*
C12	0.3867 (6)	0.18121 (19)	0.1531 (3)	0.0351 (9)
C13	0.1542 (8)	0.1208 (2)	0.2525 (4)	0.0555 (12)
H13	0.0296	0.0948	0.2698	0.067*
C14	0.3335 (8)	0.1414 (2)	0.3281 (4)	0.0491 (11)
H14	0.3554	0.1322	0.4069	0.059*
C15	0.4810 (7)	0.1791 (2)	0.2662 (4)	0.0478 (11)
H15	0.6194	0.1992	0.2968	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0775 (5)	0.0397 (4)	0.0728 (5)	−0.0020 (2)	−0.0020 (3)	−0.0044 (2)
N1	0.048 (2)	0.059 (2)	0.028 (2)	−0.0062 (17)	0.0100 (16)	−0.0044 (16)
N2	0.039 (2)	0.059 (2)	0.045 (2)	−0.0109 (17)	0.0019 (17)	0.0040 (17)
C1	0.031 (2)	0.049 (2)	0.026 (2)	−0.0040 (17)	−0.0014 (16)	−0.0007 (17)
C2	0.033 (2)	0.047 (2)	0.022 (2)	−0.0015 (17)	0.0055 (16)	0.0024 (15)
C3	0.031 (2)	0.065 (3)	0.029 (2)	0.0060 (19)	0.0012 (18)	0.0050 (19)
C4	0.041 (2)	0.048 (3)	0.040 (3)	0.0109 (19)	0.0034 (19)	0.0049 (19)
C5	0.049 (2)	0.038 (2)	0.033 (2)	−0.0005 (18)	0.0112 (19)	−0.0012 (17)
C6	0.038 (2)	0.045 (3)	0.037 (2)	−0.0014 (18)	−0.0002 (19)	0.0006 (17)
C7	0.0279 (19)	0.043 (2)	0.038 (2)	0.0034 (17)	0.0009 (17)	0.0046 (17)
C8	0.037 (2)	0.053 (3)	0.025 (2)	−0.0065 (19)	0.0006 (16)	−0.0072 (18)
C9	0.049 (3)	0.078 (4)	0.036 (3)	−0.002 (2)	0.005 (2)	−0.014 (2)
C10	0.065 (3)	0.070 (4)	0.051 (3)	0.006 (3)	0.004 (2)	−0.021 (2)
C11	0.049 (3)	0.058 (3)	0.043 (3)	−0.004 (2)	0.007 (2)	−0.009 (2)
C12	0.031 (2)	0.040 (2)	0.035 (2)	−0.0054 (16)	0.0081 (17)	−0.0051 (16)
C13	0.052 (3)	0.055 (3)	0.065 (3)	−0.003 (2)	0.026 (2)	0.012 (2)
C14	0.063 (3)	0.051 (3)	0.037 (3)	0.001 (2)	0.017 (2)	0.0028 (19)
C15	0.046 (2)	0.069 (3)	0.029 (2)	−0.017 (2)	0.0059 (19)	−0.006 (2)

Geometric parameters (Å, º) top

Br1—C5	1.905 (4)	C5—C6	1.365 (5)
N1—C9	1.355 (6)	C6—C7	1.379 (5)
N1—C8	1.364 (5)	C6—H6	0.9300
N1—H1N	0.8600	C7—H7	0.9300
N2—C12	1.356 (5)	C8—C11	1.336 (6)
N2—C13	1.368 (6)	C9—C10	1.326 (7)
N2—H2N	0.8600	C9—H9	0.9300
C1—C12	1.505 (5)	C10—C11	1.430 (6)
C1—C2	1.506 (5)	C10—H10	0.9300
C1—C8	1.529 (6)	C11—H11	0.9300
C1—H1	0.9800	C12—C15	1.366 (5)
C2—C3	1.381 (5)	C13—C14	1.344 (6)
C2—C7	1.395 (5)	C13—H13	0.9300
C3—C4	1.372 (6)	C14—C15	1.400 (5)
C3—H3	0.9300	C14—H14	0.9300
C4—C5	1.374 (6)	C15—H15	0.9300
C4—H4	0.9300

C9—N1—C8	110.0 (4)	C6—C7—C2	121.1 (4)
C9—N1—H1N	125.0	C6—C7—H7	119.4
C8—N1—H1N	125.0	C2—C7—H7	119.4
C12—N2—C13	109.8 (4)	C11—C8—N1	107.4 (4)
C12—N2—H2N	125.1	C11—C8—C1	131.9 (4)
C13—N2—H2N	125.1	N1—C8—C1	120.6 (4)
C12—C1—C2	111.0 (3)	C10—C9—N1	107.8 (4)
C12—C1—C8	110.7 (3)	C10—C9—H9	126.1
C2—C1—C8	113.4 (3)	N1—C9—H9	126.1
C12—C1—H1	107.1	C9—C10—C11	107.7 (4)
C2—C1—H1	107.1	C9—C10—H10	126.2
C8—C1—H1	107.1	C11—C10—H10	126.2
C3—C2—C7	117.4 (4)	C8—C11—C10	107.2 (4)
C3—C2—C1	120.8 (3)	C8—C11—H11	126.4
C7—C2—C1	121.8 (3)	C10—C11—H11	126.4
C4—C3—C2	122.1 (4)	N2—C12—C15	106.6 (4)
C4—C3—H3	118.9	N2—C12—C1	121.4 (3)
C2—C3—H3	118.9	C15—C12—C1	132.0 (3)
C3—C4—C5	118.8 (4)	C14—C13—N2	107.9 (4)
C3—C4—H4	120.6	C14—C13—H13	126.0
C5—C4—H4	120.6	N2—C13—H13	126.0
C6—C5—C4	121.2 (4)	C13—C14—C15	107.4 (4)
C6—C5—Br1	118.5 (3)	C13—C14—H14	126.3
C4—C5—Br1	120.3 (3)	C15—C14—H14	126.3
C5—C6—C7	119.4 (4)	C12—C15—C14	108.3 (4)
C5—C6—H6	120.3	C12—C15—H15	125.9
C7—C6—H6	120.3	C14—C15—H15	125.9

C12—C1—C2—C3	−100.7 (4)	C12—C1—C8—N1	−164.7 (3)
C8—C1—C2—C3	133.9 (4)	C2—C1—C8—N1	−39.2 (5)
C12—C1—C2—C7	77.2 (4)	C8—N1—C9—C10	0.8 (5)
C8—C1—C2—C7	−48.1 (5)	N1—C9—C10—C11	−0.4 (6)
C7—C2—C3—C4	−0.4 (5)	N1—C8—C11—C10	0.6 (5)
C1—C2—C3—C4	177.7 (4)	C1—C8—C11—C10	176.9 (4)
C2—C3—C4—C5	0.7 (6)	C9—C10—C11—C8	−0.1 (5)
C3—C4—C5—C6	−1.4 (6)	C13—N2—C12—C15	0.5 (5)
C3—C4—C5—Br1	177.4 (3)	C13—N2—C12—C1	−179.1 (4)
C4—C5—C6—C7	1.7 (6)	C2—C1—C12—N2	139.7 (4)
Br1—C5—C6—C7	−177.2 (3)	C8—C1—C12—N2	−93.5 (4)
C5—C6—C7—C2	−1.3 (6)	C2—C1—C12—C15	−39.8 (6)
C3—C2—C7—C6	0.7 (5)	C8—C1—C12—C15	87.0 (5)
C1—C2—C7—C6	−177.3 (3)	C12—N2—C13—C14	−0.3 (5)
C9—N1—C8—C11	−0.8 (5)	N2—C13—C14—C15	−0.1 (5)
C9—N1—C8—C1	−177.7 (4)	N2—C12—C15—C14	−0.6 (5)
C12—C1—C8—C11	19.3 (6)	C1—C12—C15—C14	179.0 (4)
C2—C1—C8—C11	144.8 (4)	C13—C14—C15—C12	0.4 (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···A	D—H	H···A	D···A	D—H···A
N2—H2N···Cg1ⁱ	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···Cg3^iv	0.93	2.79	3.564 (5)	142
C5—Br1···Cg2^v	1.91 (1)	3.70 (1)	5.595 (4)	171 (1)

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