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

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ISSN: 2056-9890

2,2′-(p-Phenyl­ene)bis­­(4,5-di­hydro-1H-imidazol-3-ium) bis­­(3-nitro­benzoate)

aSchool of Chemical and Material Engineering, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu Province 214122, People's Republic of China, and bCollege of Pharmacy, GuangDong Pharmaceutical University, Guangzhou, Guangdong Province 510006, People's Republic of China
*Correspondence e-mail: chunxiaren@yahoo.com.cn, smshang@126.com

(Received 6 December 2010; accepted 19 December 2010; online 8 January 2011)

In the title compound, C12H16N4+·2C7H4NO4, the complete 2,2′-(p-phenyl­ene)bis­(4,5-dihydro-1H-imidazol-3-ium) (bib) dication is generated by crystallographic inversion symmetry. The bib cations reside on crystallographic inversion centers, which coincide with the centroids of the respective benzene rings. In the cation, the imidazole ring adopts an envelop conformation with the flap atom displaced by 0.082 (3) Å from the plane through the other ring atoms. In the crystal, the cations and anions are linked through inter­molecular N—H⋯O hydrogen bonds, forming chains running along the a axis. C—H⋯O inter­actions also occur. Weak ππ contacts between the imidazole rings of bib and between the benzene rings of NB [centroid–centroid distances = 3.501 (1) and 3.281 (2) Å, respectively] may further stabilize the structure.

Related literature

For general background to supra­molecular inter­actions, see: Jeffrey (1997[Jeffrey, G. A. (1997). An Introduction to Hydrogen Bonding. New York: Oxford University Press Inc.]). For the structures of metal complexes with imidazole ligands reported by our group, see: Ren, Ye, He et al. (2004[Ren, C.-X., Ye, B.-H., He, F., Cheng, L. & Chen, X.-M. (2004). CrystEngComm, 6, 200-206.]); Ren, Ye, Zhu et al. (2004[Ren, C.-X., Ye, B.-H., Zhu, H.-L., Shi, J.-X. & Chen, X.-M. (2004). Inorg. Chim. Acta, 357, 443-450.]); Ren et al. (2007[Ren, C.-X., Cheng, L., Ye, B.-H. & Chen, X.-M. (2007). Inorg. Chim. Acta, 360, 3741-3747.], 2009[Ren, C.-X., Li, S.-Y., Yin, Z.-Z., Lu, X. & Ding, Y.-Q. (2009). Acta Cryst. E65, m572-m573.]).

[Scheme 1]

Experimental

Crystal data
  • C12H16N42+·2C7H4NO4

  • Mr = 548.51

  • Triclinic, [P \overline 1]

  • a = 6.9882 (12) Å

  • b = 7.4165 (12) Å

  • c = 13.233 (2) Å

  • α = 81.343 (3)°

  • β = 82.443 (3)°

  • γ = 62.699 (2)°

  • V = 600.96 (17) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 0.12 mm−1

  • T = 273 K

  • 0.67 × 0.55 × 0.42 mm

Data collection
  • Bruker SMART APEX CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1998[Bruker (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.927, Tmax = 0.953

  • 3714 measured reflections

  • 2575 independent reflections

  • 1676 reflections with I > 2σ(I)

  • Rint = 0.016

Refinement
  • R[F2 > 2σ(F2)] = 0.053

  • wR(F2) = 0.151

  • S = 1.07

  • 2575 reflections

  • 181 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.28 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C6—H6⋯O2i 0.93 2.48 3.283 (3) 144
N1—H1⋯O1ii 0.86 1.97 2.763 (3) 153
N2—H2⋯O2iii 0.86 1.80 2.646 (3) 166
Symmetry codes: (i) -x+2, -y+1, -z; (ii) -x+1, -y+1, -z; (iii) x+1, y-1, z.

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT-Plus (Bruker, 1998[Bruker (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT-Plus; 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: SHELXTL (Sheldrick, 2008)[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

Attention has been recently focused on the use of supramolecular interactions, such as hydrogen bonding and π-π interactions, in the controlled assembly of supramolecular architectures (Jeffrey, 1997). Hydrogen bonds often play a dominant role in crystal engineering because of their combine strength with directionality. We have reported several complexes having an imidazole entity, and have concluded that hydrogen bonding involving this group influences the geometry around the metal atom and the crystallization mechanism (Ren, Ye, He et al., 2004; Ren, Ye, Zhu et al., 2004; Ren, et al., 2007; Ren, et al., 2009). As a further contribution to this field, we describe herein the synthesis and crystal structure of the title compound.

The asymmetric unit of the title compound (Fig. 1) contains one-half of 1,4-bis(4,5-dihydro-H,4H–imidazol-2-yl)benzene (bib) cation and one 3-nitrobenzoate (NB) anion. In the bib molecule, the imidazole ring A (N1/N2/C1—C3) adopts an envelop conformation with atom C4 displaced by 0.082 (3)/A from the plane of the other ring atoms. Rings B (C4/C5/C6/C4'/C5'/C6') [symmetry code ('): 3 - x,-y,-z] are, of course, planar and they are oriented at a dihedral angle of 96.6/%.

In the crystal structure, the bib and NB ligands are joined together through hydrogen bonds between the carboxy oxygen in NB and nitrogen atom in bib to give a macrocycle N1—H1···O1 and N2—H2···O2 with the hydrogen bond geometry given in Table 1, and a face-to-face intracyclic π-π interaction at 3.50 (1) /A. Each bib group also features another macrocycles, resulting in 1-D chains running along the a axis. As illustracted in Fig. 2, the adjacent NB ligands are furthermore linked in the antiparallel alignment with offset along the bc plane by π-π contacts (3.28 (1)/A) in a 3-D structure (Fig. 2). Weak intermolecular C—H···O contacts contribute to the stability of the layered structure (Table 1).

Related literature top

For general background to supramolecular interactions, see: Jeffrey (1997). For the structures of related metal complexes with imidazole ligands reported by our group, see: Ren, Ye, He et al. (2004); Ren, Ye, Zhu et al. (2004); Ren et al. (2007, 2009).

Experimental top

All the reagents and solvents employed were commercially available and used as received without further purification.

Syntheses of 1,4-bis(4,5-dihydro-1H-imidazol-2-yl)benzene: a mixture of 1,4-Benzenedicarboxylic acid (2.31 g, 13.9 mmol), ethylenediamine (3.70 ml, 50 mmol), ethylenediamine dihydrochloride(6.64 g, 50 mmol) and toluene-p-sulfonic acid (0.208 g, 1.09 mmol) in ethyleneglycol (20 ml) was refluxed at 198/%C for 3 h. Then about half of the ethylene glycol solvent was then slowly removed by distillation at 120 /%C. The residue was dissolved in a mixture of water (40 ml) and concentrated hydrochloric acid (11 M, 3 ml). The addition of 50% aqueous sodium hydroxide gave a yellow precipitate that was recrystallized by methonal (yield 83% based on 1,4-benzenedicarboxylic acid (ca 2.50 g). Calc. for C12H14N4: C 67.27; H 6.59; N 26.15%. Found: C 66.98; H 6.92; N 26.08%. IR (KBr, cm-1): 3188(m), 2936(m), 2866(m), 1606(s), 1532(s), 1466(s), 1345(m), 1270(s), 1191(w), 1080(w), 981(m), 855(m).

Syntheses of the title compound: to a solution of 1,4-bis(4,5-dihydro-1H-imidazol-2-yl)benzene (0.0109 g, 0.05 mmol) in methonal (1 ml), an acetonitrile solution (1 ml) of 3-nitrobenzoic acid (0.0069 g, 0.06 mmol) was added and stirred 10 min at room temperature. The solution was allowed at room temperature in 10 ml diethyl diether for 25 h by slow evaporation. Colorless prismatic crystals of the title compound were obtained, which were collected by filtration, washed with water and dried in vacuum desiccator over silica gel (0.0095 g, 41%). IR (KBr,cm-1): 3436(s), 3080(w), 2924(m), 1618(s), 1560(m), 1524(s), 1383(s), 1370(s), 1351(s), 1282(m), 720(m), 696(w).

Refinement top

Anisotropic thermal parameters were applied to all nonhydrogen atoms. The organic hydrogen atoms attached to C atoms and N atom were fixed geometrically and treated as riding with C—H = 0.93 Å (aromatic) or 0.97 Å (methylene) and N—H = 0.86 Å with Uiso(H) = 1.2 Ueq(C or N). Rigid bond restraint instruction DELU was applied to improve the anisotropic displacement parameters involving N3 and C12.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The structure of the title complex 1,4-bis(4,5-dihydro-H,4H-imidazol-2-yl)benzene bis(3-nitrobenzoate) showing 30° probability displacement ellipsoids.
[Figure 2] Fig. 2. Crystal packing of the title compound viewed along the baxis. H atoms not involved in hydrogen bonding are omitted for clarity.
2,2'-(p-Phenylene)bis(4,5-dihydro-1H-imidazol-3-ium) bis(3-nitrobenzoate) top
Crystal data top
C12H16N42+·2C7H4NO4V = 600.96 (17) Å3
Mr = 548.51Z = 1
Triclinic, P1F(000) = 286
Hall symbol: -P 1Dx = 1.516 Mg m3
a = 6.9882 (12) ÅMo Kα radiation, λ = 0.71073 Å
b = 7.4165 (12) ŵ = 0.12 mm1
c = 13.233 (2) ÅT = 273 K
α = 81.343 (3)°Block, colorless
β = 82.443 (3)°0.67 × 0.55 × 0.42 mm
γ = 62.699 (2)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2575 independent reflections
Radiation source: fine-focus sealed tube1676 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.016
ϕ and ω scansθmax = 27.0°, θmin = 1.6°
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
h = 88
Tmin = 0.927, Tmax = 0.953k = 99
3714 measured reflectionsl = 168
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)] = 0.053Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.151H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0613P)2 + 0.1694P]
where P = (Fo2 + 2Fc2)/3
2575 reflections(Δ/σ)max < 0.001
181 parametersΔρmax = 0.20 e Å3
1 restraintΔρmin = 0.28 e Å3
Crystal data top
C12H16N42+·2C7H4NO4γ = 62.699 (2)°
Mr = 548.51V = 600.96 (17) Å3
Triclinic, P1Z = 1
a = 6.9882 (12) ÅMo Kα radiation
b = 7.4165 (12) ŵ = 0.12 mm1
c = 13.233 (2) ÅT = 273 K
α = 81.343 (3)°0.67 × 0.55 × 0.42 mm
β = 82.443 (3)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer
2575 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1998)
1676 reflections with I > 2σ(I)
Tmin = 0.927, Tmax = 0.953Rint = 0.016
3714 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0531 restraint
wR(F2) = 0.151H-atom parameters constrained
S = 1.07Δρmax = 0.20 e Å3
2575 reflectionsΔρmin = 0.28 e Å3
181 parameters
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'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 > 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
C10.7607 (4)0.1903 (4)0.18562 (17)0.0483 (6)
H1A0.73980.25920.24580.058*
H1B0.68390.10750.19810.058*
C20.6871 (4)0.3430 (3)0.09029 (18)0.0492 (6)
H2A0.59610.31470.05210.059*
H2B0.60930.48200.10830.059*
C31.0544 (3)0.1481 (3)0.07401 (15)0.0383 (5)
C41.2831 (3)0.0707 (3)0.03509 (15)0.0373 (5)
C51.3404 (3)0.1420 (3)0.06192 (15)0.0414 (5)
H51.23370.23730.10340.050*
C61.5554 (4)0.0716 (3)0.09660 (15)0.0416 (5)
H61.59250.11950.16150.050*
C70.1900 (4)0.5421 (5)0.2448 (2)0.0620 (8)
C80.2163 (3)0.3932 (3)0.33993 (16)0.0437 (5)
C90.1925 (4)0.2191 (4)0.33805 (19)0.0529 (6)
H90.16910.18870.27650.064*
C100.2027 (4)0.0885 (4)0.4264 (2)0.0639 (7)
H100.18490.02750.42390.077*
C110.2391 (4)0.1307 (4)0.5170 (2)0.0620 (7)
H110.24450.04520.57690.074*
C120.2671 (3)0.3009 (4)0.51797 (16)0.0507 (6)
C130.2561 (3)0.4345 (3)0.43168 (17)0.0462 (5)
H130.27500.54970.43500.055*
N10.8925 (3)0.3081 (3)0.03187 (14)0.0482 (5)
H10.90550.38220.02260.058*
N20.9901 (3)0.0671 (3)0.15833 (13)0.0438 (5)
H21.07210.04390.19300.053*
N30.3060 (4)0.3471 (5)0.61616 (18)0.0776 (8)
O10.1555 (3)0.4959 (3)0.16467 (14)0.0884 (7)
O20.2025 (3)0.7013 (3)0.25649 (18)0.0916 (8)
O30.3241 (4)0.5037 (6)0.6153 (2)0.1100 (10)
O40.3135 (4)0.2288 (5)0.69216 (16)0.1205 (11)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0495 (13)0.0543 (13)0.0410 (12)0.0242 (11)0.0023 (10)0.0025 (10)
C20.0456 (13)0.0468 (12)0.0473 (13)0.0152 (10)0.0034 (10)0.0009 (10)
C30.0477 (12)0.0387 (10)0.0286 (10)0.0187 (9)0.0089 (9)0.0010 (8)
C40.0446 (12)0.0356 (10)0.0298 (10)0.0160 (9)0.0068 (8)0.0011 (8)
C50.0472 (12)0.0380 (11)0.0323 (11)0.0142 (9)0.0099 (9)0.0053 (8)
C60.0516 (13)0.0424 (11)0.0273 (10)0.0197 (10)0.0045 (9)0.0040 (8)
C70.0410 (13)0.0717 (18)0.0494 (16)0.0137 (12)0.0021 (11)0.0233 (13)
C80.0359 (11)0.0477 (12)0.0367 (12)0.0129 (9)0.0031 (9)0.0074 (9)
C90.0513 (14)0.0599 (15)0.0463 (14)0.0226 (11)0.0085 (11)0.0052 (11)
C100.0610 (16)0.0510 (14)0.080 (2)0.0292 (13)0.0097 (14)0.0104 (13)
C110.0513 (15)0.0686 (17)0.0530 (16)0.0235 (13)0.0059 (12)0.0225 (13)
C120.0350 (12)0.0701 (16)0.0336 (12)0.0131 (11)0.0033 (9)0.0013 (11)
C130.0362 (11)0.0487 (12)0.0484 (13)0.0153 (10)0.0014 (9)0.0037 (10)
N10.0481 (11)0.0478 (10)0.0372 (10)0.0146 (9)0.0047 (8)0.0072 (8)
N20.0464 (10)0.0434 (10)0.0365 (10)0.0181 (8)0.0060 (8)0.0062 (8)
N30.0438 (13)0.124 (2)0.0481 (14)0.0212 (14)0.0029 (10)0.0174 (15)
O10.0837 (14)0.1023 (16)0.0365 (10)0.0115 (12)0.0080 (9)0.0177 (10)
O20.0766 (14)0.0759 (14)0.1167 (19)0.0418 (12)0.0346 (12)0.0561 (13)
O30.0816 (17)0.173 (3)0.0934 (19)0.0593 (18)0.0042 (13)0.0671 (19)
O40.0984 (18)0.183 (3)0.0363 (12)0.0305 (18)0.0134 (11)0.0122 (15)
Geometric parameters (Å, º) top
C1—N21.462 (3)C7—O21.257 (4)
C1—C21.531 (3)C7—C81.514 (3)
C1—H1A0.9700C8—C91.380 (3)
C1—H1B0.9700C8—C131.387 (3)
C2—N11.468 (3)C9—C101.388 (3)
C2—H2A0.9700C9—H90.9300
C2—H2B0.9700C10—C111.367 (4)
C3—N21.312 (3)C10—H100.9300
C3—N11.317 (3)C11—C121.366 (4)
C3—C41.476 (3)C11—H110.9300
C4—C6i1.393 (3)C12—C131.380 (3)
C4—C51.394 (3)C12—N31.481 (3)
C5—C61.383 (3)C13—H130.9300
C5—H50.9300N1—H10.8600
C6—C4i1.393 (3)N2—H20.8600
C6—H60.9300N3—O41.221 (3)
C7—O11.246 (4)N3—O31.222 (4)
N2—C1—C2102.53 (17)C9—C8—C13118.9 (2)
N2—C1—H1A111.3C9—C8—C7120.8 (2)
C2—C1—H1A111.3C13—C8—C7120.2 (2)
N2—C1—H1B111.3C8—C9—C10121.2 (2)
C2—C1—H1B111.3C8—C9—H9119.4
H1A—C1—H1B109.2C10—C9—H9119.4
N1—C2—C1102.37 (17)C11—C10—C9119.9 (2)
N1—C2—H2A111.3C11—C10—H10120.1
C1—C2—H2A111.3C9—C10—H10120.1
N1—C2—H2B111.3C12—C11—C10118.7 (2)
C1—C2—H2B111.3C12—C11—H11120.7
H2A—C2—H2B109.2C10—C11—H11120.7
N2—C3—N1111.85 (19)C11—C12—C13122.8 (2)
N2—C3—C4122.98 (18)C11—C12—N3118.7 (2)
N1—C3—C4125.13 (18)C13—C12—N3118.4 (3)
C6i—C4—C5119.30 (19)C12—C13—C8118.5 (2)
C6i—C4—C3119.93 (18)C12—C13—H13120.7
C5—C4—C3120.75 (18)C8—C13—H13120.7
C6—C5—C4120.20 (19)C3—N1—C2110.95 (18)
C6—C5—H5119.9C3—N1—H1124.5
C4—C5—H5119.9C2—N1—H1124.5
C5—C6—C4i120.50 (19)C3—N2—C1111.14 (17)
C5—C6—H6119.7C3—N2—H2124.4
C4i—C6—H6119.7C1—N2—H2124.4
O1—C7—O2127.2 (2)O4—N3—O3124.9 (3)
O1—C7—C8117.2 (3)O4—N3—C12117.8 (3)
O2—C7—C8115.6 (3)O3—N3—C12117.3 (3)
Symmetry code: (i) x+3, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O2ii0.932.483.283 (3)144
N1—H1···O1iii0.861.972.763 (3)153
N2—H2···O2iv0.861.802.646 (3)166
Symmetry codes: (ii) x+2, y+1, z; (iii) x+1, y+1, z; (iv) x+1, y1, z.

Experimental details

Crystal data
Chemical formulaC12H16N42+·2C7H4NO4
Mr548.51
Crystal system, space groupTriclinic, P1
Temperature (K)273
a, b, c (Å)6.9882 (12), 7.4165 (12), 13.233 (2)
α, β, γ (°)81.343 (3), 82.443 (3), 62.699 (2)
V3)600.96 (17)
Z1
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.67 × 0.55 × 0.42
Data collection
DiffractometerBruker SMART APEX CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1998)
Tmin, Tmax0.927, 0.953
No. of measured, independent and
observed [I > 2σ(I)] reflections
3714, 2575, 1676
Rint0.016
(sin θ/λ)max1)0.639
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.053, 0.151, 1.07
No. of reflections2575
No. of parameters181
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.20, 0.28

Computer programs: SMART (Bruker, 1998), SAINT-Plus (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C6—H6···O2i0.932.483.283 (3)144
N1—H1···O1ii0.861.972.763 (3)153
N2—H2···O2iii0.861.802.646 (3)166
Symmetry codes: (i) x+2, y+1, z; (ii) x+1, y+1, z; (iii) x+1, y1, z.
 

Acknowledgements

This work was generously supported by the National Natural Science Foundation of China (No. 20701016).

References

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