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Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): o566.
Published online 2010 February 10. doi:  10.1107/S1600536810004459
PMCID: PMC2983617

Dibenzyl 3,3′-diethyl-4,4′-dimethyl-2,2′-methylenebis(pyrrole-5-carboxylate)

Abstract

In the title compound, C31H34N2O4, the two pyrrole rings are bent around the central methyl­ene C atom, making a dihedral angle of 64.83 (7)°. In the crystal, mol­ecules are linked into dimers via N—H(...)O=C hydrogen bonds. These dimers are packed through π(...)π inter­actions between neighboring pyrrole rings with a separation between the mean planes of symmetry-related pyrrole rings of 3.61 (2) Å and a centroid–centroid distance of 4.33 Å. Parallel phenyl groups in neighboring dimers also exhibit efficient π(...)π inter­actions, characterized by an inter­plane separation of 3.378 (8) Å and a centroid–centroid distance of 3.97 Å.

Related literature

For the preparation of the title compound, see: Twyman & Sanders (1999 [triangle]). For related structures, see: Bonnett et al. (1972 [triangle]); Senge (2005 [triangle]); Vega et al. (2003 [triangle]). For the use of dipyrrylmethanes in organic synthesis, see: Chen et al. (2000 [triangle]) and references cited therein; Jasat & Dolphin (1997 [triangle]); Shanmugathasan et al. (2000 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-0o566-scheme1.jpg

Experimental

Crystal data

  • C31H34N2O4
  • M r = 498.60
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-0o566-efi1.jpg
  • a = 14.2002 (9) Å
  • b = 7.9220 (5) Å
  • c = 25.0939 (16) Å
  • β = 104.373 (3)°
  • V = 2734.6 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 162 K
  • 0.35 × 0.32 × 0.08 mm

Data collection

  • Bruker SMART APEX CCD diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 1998 [triangle]) T min = 0.972, T max = 0.993
  • 37570 measured reflections
  • 6304 independent reflections
  • 4371 reflections with I > 2σ(I)
  • R int = 0.059

Refinement

  • R[F 2 > 2σ(F 2)] = 0.049
  • wR(F 2) = 0.136
  • S = 1.05
  • 6304 reflections
  • 346 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.29 e Å−3
  • Δρmin = −0.26 e Å−3

Data collection: SMART (Bruker, 1998 [triangle]); cell refinement: SAINT (Bruker, 1998 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, globle. DOI: 10.1107/S1600536810004459/bh2271sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810004459/bh2271Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported by Kumoh National Institute of Technology.

supplementary crystallographic information

Comment

Dipyrrylmethanes have been widely used as versatile precursors in the synthesis of porphyrins (Shanmugathasan et al., 2000), related polypyrrolic macrocycles (Jasat et al., 1997) and pigments (Chen et al., 2000). For the synthesis of novel porphyrins, the title compound was prepared and its crystal structure determined. Related structure of dipyrrylmethanes derivatives were previously reported (Bonnett et al., 1972; Senge et al., 2005; Vega et al., 2003).

The molecular structure of the title compound is shown in Figure 1. The two pyrrole rings are bent with the dihedral angle of 64.83 (7)° around the attached methylene carbon atom C5. As shown in Figure 2, the molecules are linked by paired N—H···O=C hydrogen bonds into dimers in the crystal lattice. The structural parameters for the intermolecular hydrogen bonds resulting in the formation of dimers are given in Table 1. These dimeric units are packed through π···π interactions between neighboring pyrrole rings as well as neighboring phenyl rings as shown in Figure 3. The interplane and a centroid-to-centroid separations between the parallel pyrrole groups are 3.61 (2) and 4.33 Å, respectively. The parallel phenyl groups in neighboring dimers in the crystal also exhibit efficient π···π interactions: interplane separation of 3.378 (8) Å, and centroid-to-centroid distance of 3.973 Å.

Experimental

The title compound was prepared according to the reported procedure (Twyman et al., 1999). Crystals suitable for X-ray crystallographic work were grown by slow vapor diffusion of n-hexane into a toluene solution.

Refinement

All non-H atoms were refined anisotropically. C-bonded H atoms were placed in geometrically ideal positions and refined as riding to their parent C atoms with C—H bond lengths fixed to 0.99 (methylene) or 0.98 Å (methyl). Displacement parameters were computed as Uiso(H) = 1.2Ueq(carrier C) for methylene groups and Uiso(H) = 1.5Ueq(carrier C) for methyl groups. Atoms H1 and H2, bonded to N1 and N2, were found in a difference map and refined freely (coordinates and displacement parameters).

Figures

Fig. 1.
The molecular structure of the title compound showing 30 % probability displacement ellipsoids. Hydrogen atoms except for the N—H groups are omitted for clarity.
Fig. 2.
Hydrogen bonded dimer in the crystal of the title compound.
Fig. 3.
Packing diagram for the hydrogen bonded dimers of the title compound in the crystal lattice.

Crystal data

C31H34N2O4F(000) = 1064
Mr = 498.60Dx = 1.211 Mg m3
Monoclinic, P2/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yacCell parameters from 9928 reflections
a = 14.2002 (9) Åθ = 2.6–24.4°
b = 7.9220 (5) ŵ = 0.08 mm1
c = 25.0939 (16) ÅT = 162 K
β = 104.373 (3)°Plate, colourless
V = 2734.6 (3) Å30.35 × 0.32 × 0.08 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer6304 independent reflections
Radiation source: fine-focus sealed tube4371 reflections with I > 2σ(I)
graphiteRint = 0.059
[var phi] and ω scansθmax = 27.6°, θmin = 1.5°
Absorption correction: multi-scan (SADABS; Bruker, 1998)h = −18→18
Tmin = 0.972, Tmax = 0.993k = −10→10
37570 measured reflectionsl = −31→32

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.049Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.136H atoms treated by a mixture of independent and constrained refinement
S = 1.05w = 1/[σ2(Fo2) + (0.0505P)2 + 0.953P] where P = (Fo2 + 2Fc2)/3
6304 reflections(Δ/σ)max = 0.001
346 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = −0.26 e Å3
0 constraints

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

xyzUiso*/Ueq
O10.84641 (10)0.85654 (17)0.91775 (6)0.0528 (4)
O20.75643 (10)0.65074 (17)0.86750 (7)0.0603 (4)
O30.76635 (7)0.24675 (15)0.68188 (4)0.0342 (3)
O40.87580 (7)0.18152 (15)0.63406 (4)0.0334 (3)
N10.90073 (10)0.43117 (18)0.88502 (5)0.0310 (3)
H10.8449 (15)0.396 (3)0.8648 (8)0.047 (6)*
N20.90338 (9)0.17664 (17)0.77990 (5)0.0285 (3)
H20.8449 (14)0.204 (2)0.7845 (7)0.045 (5)*
C10.91713 (12)0.5906 (2)0.90767 (7)0.0339 (4)
C21.01355 (12)0.5990 (2)0.93634 (6)0.0348 (4)
C31.05588 (12)0.4413 (2)0.93042 (6)0.0327 (4)
C40.98377 (11)0.3399 (2)0.89853 (6)0.0295 (3)
C50.98552 (12)0.1610 (2)0.87970 (6)0.0319 (4)
H5A0.92830.10100.88630.038*
H5B1.04450.10510.90210.038*
C60.98473 (11)0.1445 (2)0.82008 (6)0.0294 (3)
C71.05896 (11)0.1041 (2)0.79533 (7)0.0315 (4)
C81.01998 (11)0.1126 (2)0.73787 (7)0.0310 (4)
C90.92347 (11)0.1592 (2)0.72921 (6)0.0287 (3)
C101.06422 (14)0.7464 (2)0.96891 (8)0.0461 (5)
H10A1.01610.83180.97230.069*
H10B1.11050.79540.95010.069*
H10C1.09910.70811.00560.069*
C111.07570 (12)0.0804 (3)0.69528 (7)0.0426 (4)
H11A1.05250.15660.66400.064*
H11B1.0659−0.03690.68270.064*
H11C1.14510.10040.71130.064*
C121.16037 (12)0.3931 (3)0.95415 (7)0.0422 (4)
H12A1.16520.26850.95630.051*
H12B1.18150.43790.99210.051*
C131.22892 (14)0.4582 (3)0.92102 (9)0.0538 (5)
H13A1.29520.41990.93800.081*
H13B1.22730.58180.92030.081*
H13C1.20850.41480.88330.081*
C141.16166 (11)0.0618 (2)0.82435 (7)0.0399 (4)
H14A1.17420.10080.86300.048*
H14B1.20610.12430.80670.048*
C151.18485 (14)−0.1252 (3)0.82408 (9)0.0533 (5)
H15A1.2535−0.14340.84250.080*
H15B1.1721−0.16530.78600.080*
H15C1.1440−0.18750.84350.080*
C160.84033 (13)0.7142 (2)0.89944 (8)0.0416 (4)
C170.67700 (17)0.7704 (3)0.85195 (13)0.0862 (9)
H17A0.69560.86440.83060.103*
H17B0.66140.81790.88520.103*
C180.59147 (15)0.6804 (3)0.81813 (9)0.0532 (5)
C190.58054 (18)0.6486 (3)0.76239 (10)0.0682 (7)
H19A0.63010.68280.74530.082*
C200.4995 (2)0.5688 (3)0.73183 (10)0.0717 (7)
H20A0.49370.54820.69390.086*
C210.4286 (2)0.5196 (3)0.75463 (12)0.0751 (8)
H21A0.37280.46460.73280.090*
C220.43577 (19)0.5477 (3)0.80892 (13)0.0766 (8)
H22A0.38500.51350.82500.092*
C230.51800 (19)0.6269 (3)0.84062 (10)0.0637 (6)
H23A0.52340.64450.87870.076*
C240.84815 (11)0.1997 (2)0.68106 (6)0.0276 (3)
C250.80269 (12)0.2219 (2)0.58423 (6)0.0359 (4)
H25A0.78370.34210.58440.043*
H25B0.74410.15140.58140.043*
C260.84675 (12)0.1871 (2)0.53687 (6)0.0324 (4)
C270.81372 (12)0.0548 (2)0.50133 (7)0.0405 (4)
H27A0.7629−0.01560.50690.049*
C280.85450 (14)0.0244 (3)0.45761 (7)0.0478 (5)
H28A0.8312−0.06620.43310.057*
C290.92838 (15)0.1244 (3)0.44945 (7)0.0490 (5)
H29A0.95600.10320.41930.059*
C300.96260 (15)0.2558 (3)0.48502 (8)0.0496 (5)
H30A1.01420.32470.47960.060*
C310.92170 (14)0.2872 (2)0.52860 (7)0.0414 (4)
H31A0.94520.37800.55300.050*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0556 (8)0.0344 (8)0.0696 (9)−0.0040 (6)0.0177 (7)−0.0095 (7)
O20.0426 (8)0.0386 (8)0.0881 (11)0.0093 (6)−0.0059 (7)−0.0128 (7)
O30.0246 (6)0.0458 (7)0.0335 (6)0.0038 (5)0.0095 (5)0.0045 (5)
O40.0264 (6)0.0474 (7)0.0267 (5)0.0018 (5)0.0072 (5)−0.0004 (5)
N10.0286 (7)0.0331 (8)0.0300 (7)−0.0034 (6)0.0047 (6)−0.0023 (6)
N20.0198 (6)0.0365 (8)0.0293 (7)0.0011 (6)0.0067 (5)−0.0012 (6)
C10.0390 (9)0.0325 (9)0.0308 (8)−0.0042 (7)0.0098 (7)−0.0021 (7)
C20.0396 (9)0.0388 (10)0.0255 (8)−0.0079 (8)0.0073 (7)0.0008 (7)
C30.0335 (9)0.0401 (10)0.0227 (7)−0.0062 (7)0.0035 (6)0.0036 (7)
C40.0287 (8)0.0353 (9)0.0241 (7)−0.0025 (7)0.0061 (6)0.0021 (7)
C50.0295 (8)0.0349 (9)0.0297 (8)0.0011 (7)0.0042 (7)0.0040 (7)
C60.0240 (7)0.0305 (9)0.0317 (8)−0.0014 (6)0.0035 (6)−0.0017 (7)
C70.0229 (8)0.0337 (9)0.0365 (9)−0.0017 (7)0.0046 (6)−0.0067 (7)
C80.0220 (7)0.0355 (9)0.0355 (8)−0.0026 (7)0.0073 (6)−0.0065 (7)
C90.0238 (7)0.0340 (9)0.0288 (8)−0.0018 (6)0.0074 (6)−0.0033 (7)
C100.0522 (11)0.0449 (11)0.0387 (10)−0.0128 (9)0.0062 (8)−0.0066 (9)
C110.0289 (9)0.0586 (12)0.0426 (10)0.0007 (8)0.0137 (7)−0.0106 (9)
C120.0365 (10)0.0486 (11)0.0344 (9)−0.0041 (8)−0.0044 (7)0.0032 (8)
C130.0353 (10)0.0589 (13)0.0647 (13)−0.0043 (9)0.0075 (9)0.0014 (11)
C140.0229 (8)0.0482 (11)0.0455 (10)0.0012 (7)0.0026 (7)−0.0091 (9)
C150.0381 (10)0.0506 (12)0.0624 (13)0.0104 (9)−0.0042 (9)−0.0059 (10)
C160.0437 (10)0.0353 (10)0.0461 (10)−0.0035 (8)0.0115 (8)−0.0010 (8)
C170.0564 (14)0.0475 (14)0.133 (2)0.0215 (11)−0.0170 (15)−0.0224 (15)
C180.0521 (12)0.0439 (12)0.0589 (13)0.0229 (10)0.0051 (10)−0.0037 (10)
C190.0650 (15)0.0705 (16)0.0724 (16)0.0287 (13)0.0233 (13)0.0057 (13)
C200.0748 (17)0.0749 (17)0.0536 (13)0.0352 (14)−0.0066 (13)−0.0125 (13)
C210.0650 (16)0.0567 (15)0.089 (2)0.0198 (13)−0.0085 (14)−0.0120 (14)
C220.0667 (16)0.0588 (16)0.108 (2)0.0098 (13)0.0284 (16)0.0136 (16)
C230.0788 (17)0.0564 (14)0.0533 (13)0.0223 (13)0.0112 (12)0.0034 (11)
C240.0241 (7)0.0294 (8)0.0307 (8)−0.0033 (6)0.0096 (6)−0.0001 (7)
C250.0302 (8)0.0458 (10)0.0304 (8)0.0040 (7)0.0053 (7)0.0059 (8)
C260.0316 (8)0.0368 (9)0.0276 (8)0.0038 (7)0.0051 (7)0.0050 (7)
C270.0331 (9)0.0471 (11)0.0364 (9)−0.0033 (8)−0.0005 (7)−0.0010 (8)
C280.0486 (11)0.0553 (12)0.0332 (9)0.0020 (10)−0.0018 (8)−0.0113 (9)
C290.0591 (12)0.0605 (13)0.0285 (9)0.0076 (10)0.0133 (8)−0.0004 (9)
C300.0582 (12)0.0535 (13)0.0430 (10)−0.0070 (10)0.0236 (9)0.0045 (10)
C310.0520 (11)0.0392 (10)0.0353 (9)−0.0073 (8)0.0154 (8)−0.0030 (8)

Geometric parameters (Å, °)

O1—C161.213 (2)C13—H13A0.9800
O2—C161.356 (2)C13—H13B0.9800
O2—C171.451 (2)C13—H13C0.9800
O3—C241.2249 (18)C14—C151.518 (3)
O4—C241.3400 (18)C14—H14A0.9900
O4—C251.4490 (18)C14—H14B0.9900
N1—C41.352 (2)C15—H15A0.9800
N1—C11.381 (2)C15—H15B0.9800
N1—H10.87 (2)C15—H15C0.9800
N2—C61.356 (2)C17—C181.481 (3)
N2—C91.3778 (19)C17—H17A0.9900
N2—H20.893 (19)C17—H17B0.9900
C1—C21.381 (2)C18—C231.371 (3)
C1—C161.442 (3)C18—C191.391 (3)
C2—C31.410 (3)C19—C201.368 (4)
C2—C101.502 (2)C19—H19A0.9500
C3—C41.388 (2)C20—C211.334 (4)
C3—C121.504 (2)C20—H20A0.9500
C4—C51.496 (2)C21—C221.359 (4)
C5—C61.499 (2)C21—H21A0.9500
C5—H5A0.9900C22—C231.389 (4)
C5—H5B0.9900C22—H22A0.9500
C6—C71.387 (2)C23—H23A0.9500
C7—C81.412 (2)C25—C261.500 (2)
C7—C141.497 (2)C25—H25A0.9900
C8—C91.383 (2)C25—H25B0.9900
C8—C111.501 (2)C26—C271.381 (2)
C9—C241.437 (2)C26—C311.384 (2)
C10—H10A0.9800C27—C281.383 (3)
C10—H10B0.9800C27—H27A0.9500
C10—H10C0.9800C28—C291.370 (3)
C11—H11A0.9800C28—H28A0.9500
C11—H11B0.9800C29—C301.379 (3)
C11—H11C0.9800C29—H29A0.9500
C12—C131.519 (3)C30—C311.382 (2)
C12—H12A0.9900C30—H30A0.9500
C12—H12B0.9900C31—H31A0.9500
C16—O2—C17115.28 (16)C15—C14—H14A108.8
C24—O4—C25115.60 (12)C7—C14—H14B108.8
C4—N1—C1109.76 (14)C15—C14—H14B108.8
C4—N1—H1125.8 (13)H14A—C14—H14B107.7
C1—N1—H1124.5 (13)C14—C15—H15A109.5
C6—N2—C9109.53 (13)C14—C15—H15B109.5
C6—N2—H2126.6 (12)H15A—C15—H15B109.5
C9—N2—H2123.8 (12)C14—C15—H15C109.5
N1—C1—C2107.62 (15)H15A—C15—H15C109.5
N1—C1—C16121.18 (15)H15B—C15—H15C109.5
C2—C1—C16131.20 (16)O1—C16—O2122.53 (17)
C1—C2—C3107.20 (15)O1—C16—C1126.65 (18)
C1—C2—C10126.87 (17)O2—C16—C1110.82 (16)
C3—C2—C10125.92 (16)O2—C17—C18108.16 (17)
C4—C3—C2107.49 (14)O2—C17—H17A110.1
C4—C3—C12126.53 (16)C18—C17—H17A110.1
C2—C3—C12125.98 (15)O2—C17—H17B110.1
N1—C4—C3107.93 (15)C18—C17—H17B110.1
N1—C4—C5120.59 (14)H17A—C17—H17B108.4
C3—C4—C5131.48 (15)C23—C18—C19116.8 (2)
C4—C5—C6113.68 (13)C23—C18—C17120.8 (2)
C4—C5—H5A108.8C19—C18—C17122.3 (2)
C6—C5—H5A108.8C20—C19—C18121.0 (2)
C4—C5—H5B108.8C20—C19—H19A119.5
C6—C5—H5B108.8C18—C19—H19A119.5
H5A—C5—H5B107.7C21—C20—C19120.9 (2)
N2—C6—C7108.19 (14)C21—C20—H20A119.6
N2—C6—C5121.31 (13)C19—C20—H20A119.6
C7—C6—C5130.45 (14)C20—C21—C22120.4 (3)
C6—C7—C8107.30 (13)C20—C21—H21A119.8
C6—C7—C14126.19 (15)C22—C21—H21A119.8
C8—C7—C14126.51 (14)C21—C22—C23119.4 (3)
C9—C8—C7107.16 (13)C21—C22—H22A120.3
C9—C8—C11127.60 (15)C23—C22—H22A120.3
C7—C8—C11125.22 (14)C18—C23—C22121.4 (2)
N2—C9—C8107.80 (13)C18—C23—H23A119.3
N2—C9—C24118.19 (13)C22—C23—H23A119.3
C8—C9—C24133.88 (14)O3—C24—O4122.27 (14)
C2—C10—H10A109.5O3—C24—C9124.37 (14)
C2—C10—H10B109.5O4—C24—C9113.36 (13)
H10A—C10—H10B109.5O4—C25—C26107.03 (13)
C2—C10—H10C109.5O4—C25—H25A110.3
H10A—C10—H10C109.5C26—C25—H25A110.3
H10B—C10—H10C109.5O4—C25—H25B110.3
C8—C11—H11A109.5C26—C25—H25B110.3
C8—C11—H11B109.5H25A—C25—H25B108.6
H11A—C11—H11B109.5C27—C26—C31119.28 (16)
C8—C11—H11C109.5C27—C26—C25120.65 (16)
H11A—C11—H11C109.5C31—C26—C25120.07 (16)
H11B—C11—H11C109.5C26—C27—C28120.15 (17)
C3—C12—C13113.60 (15)C26—C27—H27A119.9
C3—C12—H12A108.8C28—C27—H27A119.9
C13—C12—H12A108.8C29—C28—C27120.34 (18)
C3—C12—H12B108.8C29—C28—H28A119.8
C13—C12—H12B108.8C27—C28—H28A119.8
H12A—C12—H12B107.7C28—C29—C30119.98 (17)
C12—C13—H13A109.5C28—C29—H29A120.0
C12—C13—H13B109.5C30—C29—H29A120.0
H13A—C13—H13B109.5C29—C30—C31119.88 (18)
C12—C13—H13C109.5C29—C30—H30A120.1
H13A—C13—H13C109.5C31—C30—H30A120.1
H13B—C13—H13C109.5C30—C31—C26120.35 (17)
C7—C14—C15113.73 (15)C30—C31—H31A119.8
C7—C14—H14A108.8C26—C31—H31A119.8

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1···O3i0.87 (2)2.09 (2)2.9334 (18)163.4 (18)
N2—H2···O3i0.89 (2)2.00 (2)2.8610 (17)162.8 (17)

Symmetry codes: (i) −x+3/2, y, −z+3/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BH2271).

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