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

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ISSN: 2056-9890

1,4-Bis[(1H-pyrazol-1-yl)meth­yl]benzene

aCollege of Chemical Engineering, Hebei United University, Tangshan 063009, People's Republic of China, and bQian'an College, Hebei United University, Tangshan 063009, People's Republic of China
*Correspondence e-mail: tsdgying@126.com

(Received 6 June 2011; accepted 10 June 2011; online 18 June 2011)

In the title compound, C14H14N4, the center of the phenyl­ene group is a crystallographic center of inversion. The compound is composed of three aromatic rings displaying a Z-like conformation. The dihedral angle between the pyrazole rings and the central phenyl ring is 83.84 (9)°.

Related literature

For background and coordination compounds with related ligands, see: Chang et al. (1993[Chang, W.-K., Sheu, S.-C., Lee, G.-H., Wang, Y., Ho, T.-I. & Lin, Y.-C. (1993). J. Chem. Soc. Dalton Trans. pp. 687-694.]); Hou et al. (2010[Hou, G. F., Bi, L. H., Li, B. & Wu, L. X. (2010). Inorg. Chem. 49, 6474-6483.]); Liu et al. (2011[Liu, T. F., Zhang, M. X., Zhang, W. G. & Cui, G. H. (2011). Chin. J. Struct. Chem. 30, 508-513.]). For the crystal structure of the title compound with two solvent water mol­ecules, see: Shi et al. (2009[Shi, A.-E., Hou, Y.-J., Zhang, Y.-M., Hou, G.-F. & Gao, J.-S. (2009). Acta Cryst. E65, o690.]).

[Scheme 1]

Experimental

Crystal data
  • C14H14N4

  • Mr = 238.29

  • Monoclinic, P 21 /c

  • a = 5.6088 (8) Å

  • b = 6.8183 (10) Å

  • c = 16.526 (3) Å

  • β = 97.900 (15)°

  • V = 626.01 (17) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 295 K

  • 0.20 × 0.20 × 0.19 mm

Data collection
  • Bruker SMART CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.956, Tmax = 0.996

  • 2464 measured reflections

  • 1109 independent reflections

  • 580 reflections with I > 2σ(I)

  • Rint = 0.033

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.064

  • S = 0.80

  • 1109 reflections

  • 83 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.10 e Å−3

  • Δρmin = −0.11 e Å−3

Data collection: SMART (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 1998[Bruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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

Over the past few years, efforts have been focused on the investigation of coordination polymers with flexible ligands. Flexbile ligands with two or more pyrazolyl moieties such as 1,4-bis[(1H-pyrazol-1-yl)-methyl]-benzene find numerous applications in constructing metal–organic coordination polymers (Chang et al. 1993; Hou et al. 2010; Liu et al. 2011). The crystal structure of the title compound including two water molecules of hydration has previously been described (Shi et al. 2009). We report here the crystal structure of the title compound without any solvent molecules in the crystal lattice.

In (I), the center of the phenylene group is an inversion centre, so that the asymmetric unit consists of one-half of the title compound (Fig. 1). 1,4-Bis[(1H-pyrazol-1-yl)-methyl]-benzene is composed of three aromatic rings, displaying a Z shape, with the pyrazole rings on opposite sides of the plane of the phenyl ring. The whole molecule is nonplanar, the dihedral angle of the pyrazoles with respect to the central phenyl group are 83.84 (9)°. The average bond distances and angles for the pyrazole ring are in agreement with those of previously reported related pyrazole complexes and the hydrated title compound (Liu et al.2011; Shi et al. 2009). In contrast to the structure of the same compound with additional water molecules of hydration (Shi et al. 2009), the dihedral angles of the pyrazole units with respect to the central phenyl group are 76.9 (1)° and 74.5 (1)°, respectively. The hydrated compound further forms a two-dimensional supramolecular network by the hydrogen bond interactions including the water molecules.

Related literature top

For background and coordination compounds with related ligands, see: Chang et al. (1993); Hou et al. (2010); Liu et al. (2011). For the crystal structure of the title compound with two solvent water molecules, see: Shi et al. (2009).

Experimental top

(I) was obtained as an unexpected product in an attempt to construct a supramolecular Zn complex under hydrothermal conditions. A mixture of Zn(NO3)2.6H2O (166 mg, 1 mmol), phthalic acid (150 mg, 1 mmol), NaOH (80 mg,2 mmol) and 1,4-Bis[(1H-pyrazol-1-yl)-methyl]-benzene (238 mg, 1 mmol) in H2O (12 ml) was placed in a Teflon-lined stainless vessel and heated to 453 K for 72 h. Then, the reaction system was cooled to room temperature during 24 h to give rise to colourless crystals, which were collected and washed with water. Yield 0.024 g (10% of used (I)). Analysis calculated for C14H14N4 (238.29): C 70.57, H 5.92, N 23.51%; found: C 70.38, H 5.78, N 23.38%.

Refinement top

H atoms were placed in calculated positions, with C—H = 0.93 Å or C—H = 0.97 Å and refined with a riding model, with Uiso(H) = 1.2Ueq(C). Restraints (DELU) were applied to the Uij parameters of atoms C3 and C4.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (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 molecular structure of (I), showing displacement ellipsoids at the 30% probability level for non-hydrogen atoms.
1,4-Bis[(1H-pyrazol-1-yl)methyl]benzene top
Crystal data top
C14H14N4F(000) = 252
Mr = 238.29Dx = 1.264 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1865 reflections
a = 5.6088 (8) Åθ = 5.3–24.1°
b = 6.8183 (10) ŵ = 0.08 mm1
c = 16.526 (3) ÅT = 295 K
β = 97.900 (15)°Block, colourless
V = 626.01 (17) Å30.20 × 0.20 × 0.19 mm
Z = 2
Data collection top
Bruker SMART CCD area-detector
diffractometer
1109 independent reflections
Radiation source: fine–focus sealed tube580 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
ϕ and ω scansθmax = 25.0°, θmin = 3.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 66
Tmin = 0.956, Tmax = 0.996k = 68
2464 measured reflectionsl = 1919
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.033H-atom parameters constrained
wR(F2) = 0.064 w = 1/[σ2(Fo2) + (0.0265P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.80(Δ/σ)max < 0.001
1109 reflectionsΔρmax = 0.10 e Å3
83 parametersΔρmin = 0.11 e Å3
1 restraintExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.043 (3)
Crystal data top
C14H14N4V = 626.01 (17) Å3
Mr = 238.29Z = 2
Monoclinic, P21/cMo Kα radiation
a = 5.6088 (8) ŵ = 0.08 mm1
b = 6.8183 (10) ÅT = 295 K
c = 16.526 (3) Å0.20 × 0.20 × 0.19 mm
β = 97.900 (15)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
1109 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
580 reflections with I > 2σ(I)
Tmin = 0.956, Tmax = 0.996Rint = 0.033
2464 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0331 restraint
wR(F2) = 0.064H-atom parameters constrained
S = 0.80Δρmax = 0.10 e Å3
1109 reflectionsΔρmin = 0.11 e Å3
83 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
N20.3304 (2)0.6599 (2)0.19489 (8)0.0484 (4)
N10.1491 (2)0.76019 (19)0.15110 (8)0.0450 (4)
C20.3728 (3)0.8298 (3)0.00568 (11)0.0536 (5)
H2B0.28800.71350.00880.064*
C70.2330 (3)0.4880 (3)0.20879 (10)0.0502 (5)
H7A0.31570.38620.23780.060*
C10.5185 (3)0.8528 (2)0.05491 (11)0.0525 (5)
H1A0.52940.75170.09200.063*
C30.3522 (3)0.9770 (3)0.06120 (10)0.0436 (4)
C60.0531 (3)0.6553 (3)0.13893 (11)0.0555 (5)
H6A0.19980.69590.11080.067*
C40.1899 (3)0.9606 (2)0.12664 (11)0.0562 (5)
H4A0.26061.03400.17420.067*
H4B0.03601.02030.10680.067*
C50.0058 (3)0.4783 (3)0.17507 (12)0.0588 (5)
H5A0.11110.37350.17670.071*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N20.0428 (8)0.0432 (10)0.0573 (10)0.0048 (8)0.0001 (7)0.0053 (8)
N10.0420 (8)0.0448 (9)0.0484 (9)0.0056 (8)0.0074 (7)0.0057 (8)
C20.0598 (11)0.0468 (12)0.0558 (12)0.0024 (9)0.0134 (10)0.0014 (11)
C70.0593 (13)0.0408 (12)0.0504 (12)0.0055 (10)0.0072 (10)0.0036 (10)
C10.0626 (11)0.0460 (12)0.0490 (12)0.0036 (10)0.0076 (10)0.0051 (10)
C30.0454 (10)0.0443 (11)0.0413 (11)0.0087 (9)0.0067 (8)0.0027 (10)
C60.0352 (10)0.0744 (15)0.0559 (12)0.0007 (11)0.0025 (8)0.0021 (12)
C40.0635 (11)0.0458 (12)0.0614 (13)0.0138 (9)0.0165 (10)0.0119 (10)
C50.0551 (13)0.0566 (14)0.0653 (13)0.0144 (10)0.0100 (11)0.0042 (12)
Geometric parameters (Å, º) top
N2—C71.3264 (19)C1—C3i1.380 (2)
N2—N11.3504 (16)C1—H1A0.9300
N1—C61.3324 (18)C3—C1i1.380 (2)
N1—C41.4518 (19)C3—C41.511 (2)
C2—C31.375 (2)C6—C51.356 (2)
C2—C11.386 (2)C6—H6A0.9300
C2—H2B0.9300C4—H4A0.9700
C7—C51.380 (2)C4—H4B0.9700
C7—H7A0.9300C5—H5A0.9300
C7—N2—N1104.04 (12)C2—C3—C4122.52 (16)
N2—N1—C6111.81 (13)C1i—C3—C4119.39 (16)
N2—N1—C4119.33 (14)N1—C6—C5107.47 (15)
C6—N1—C4128.81 (16)N1—C6—H6A126.3
C3—C2—C1120.76 (16)C5—C6—H6A126.3
C3—C2—H2B119.6N1—C4—C3113.74 (14)
C1—C2—H2B119.6N1—C4—H4A108.8
N2—C7—C5111.86 (16)C3—C4—H4A108.8
N2—C7—H7A124.1N1—C4—H4B108.8
C5—C7—H7A124.1C3—C4—H4B108.8
C3i—C1—C2121.18 (16)H4A—C4—H4B107.7
C3i—C1—H1A119.4C6—C5—C7104.82 (16)
C2—C1—H1A119.4C6—C5—H5A127.6
C2—C3—C1i118.07 (15)C7—C5—H5A127.6
Symmetry code: (i) x+1, y+2, z.

Experimental details

Crystal data
Chemical formulaC14H14N4
Mr238.29
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)5.6088 (8), 6.8183 (10), 16.526 (3)
β (°) 97.900 (15)
V3)626.01 (17)
Z2
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.20 × 0.20 × 0.19
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.956, 0.996
No. of measured, independent and
observed [I > 2σ(I)] reflections
2464, 1109, 580
Rint0.033
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.064, 0.80
No. of reflections1109
No. of parameters83
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.10, 0.11

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

 

Acknowledgements

The authors thank Hebei United University for supporting this work.

References

First citationBruker (1998). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChang, W.-K., Sheu, S.-C., Lee, G.-H., Wang, Y., Ho, T.-I. & Lin, Y.-C. (1993). J. Chem. Soc. Dalton Trans. pp. 687–694.  CrossRef Google Scholar
First citationHou, G. F., Bi, L. H., Li, B. & Wu, L. X. (2010). Inorg. Chem. 49, 6474–6483.  Web of Science CrossRef CAS PubMed Google Scholar
First citationLiu, T. F., Zhang, M. X., Zhang, W. G. & Cui, G. H. (2011). Chin. J. Struct. Chem. 30, 508–513.  CAS Google Scholar
First citationSheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationShi, A.-E., Hou, Y.-J., Zhang, Y.-M., Hou, G.-F. & Gao, J.-S. (2009). Acta Cryst. E65, o690.  Web of Science CSD CrossRef IUCr Journals Google Scholar

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ISSN: 2056-9890
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