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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 6| June 2011| Page o1416
doi:10.1107/S1600536811015029

2,5-Bis(5-methyl­pyrazin-2-yl)-1,3,4-oxa­diazole

Yue Ju,a Jing-Min Wu,a Cheng-Peng Lia* and Jian-Hua Guoa

aCollege of Chemistry, Tianjin Key Laboratory of Structure and Performance for Functional Molecule, Tianjin Normal University, Tianjin 300387, People's Republic of China
*Correspondence e-mail: tjnulicp@gmail.com

(Received 18 April 2011; accepted 21 April 2011; online 14 May 2011)

In the title mol­ecule, C12H10N6O, the dihedral angle between the two pyrazine rings [planar to within 0.009 (3) and 0.018 (3) Å] is 5.62 (15)°. They deviate from the central oxadiazole ring [planar to within 0.005 (3) Å] by 1.52 (16) and 5.55 (17)°, respectively. In the crystal, C—H⋯N inter­actions involving the pyrazine rings connect mol­ecules to form zigzag supramolecular chains propagating in [010].

Related literature

For background information and applications of oxadiazole derivatives, see: Schnurch et al. (2006[Schnurch, M., Flasik, R., Khan, A. F., Spina, M., Mihovilovic, M. D. & Stanetty, P. (2006). Eur. J. Org. Chem. pp. 3283-3307.]); Crabtree (2005[Crabtree, R. H. (2005). J. Organomet. Chem. 690, 5451-5457.]); Venkatakrishnan et al. (2000[Venkatakrishnan, K., von Moltke, L. L. & Greenblatt, D. J. (2000). Clin. Pharmacokinet. 38, 111-180.]). For related oxadiazole derivatives, see: Du et al. (2005[Du, M., Zhao, X.-J., Guo, J.-H. & Batten, S. R. (2005). Chem. Commun. pp. 4836-4838.], 2006[Du, M., Li, C.-P. & Guo, J.-H. (2006). Inorg. Chim. Acta, 359, 2575-2582.], 2009[Du, M. & Bu, X. H. (2009). Bull. Chem. Soc. Jpn, 82, 539-554.]).

[Scheme 1]

Experimental

Crystal data

  • C12H10N6O

  • Mr = 254.26

  • Monoclinic, P 21 /c

  • a = 3.9084 (8) Å

  • b = 19.054 (4) Å

  • c = 16.328 (4) Å

  • β = 101.64 (3)°

  • V = 1191.0 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.16 × 0.12 × 0.08 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 = 0.984, Tmax = 0.992

  • 6101 measured reflections

  • 2108 independent reflections

  • 1077 reflections with I > 2σ(I)

  • Rint = 0.074
Refinement

  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.120

  • S = 1.00

  • 2108 reflections

  • 174 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C11—H11⋯N2i 0.93 2.59 3.414 (4) 148
Symmetry code: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART, SAINT and SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SMART, SAINT and SHELXTL. 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: DIAMOND (Brandenburg, 1999[Brandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXTL (Bruker, 2007[Bruker (2007). SMART, SAINT and SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811015029/su2270sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811015029/su2270Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811015029/su2270Isup3.cml

checkCIF report


Comment top

Currently derivatives of oxadiazole systems are of growing research interest, as they are precursors to functional N-heterocyclic compounds, as well as being used in pharmaceuticals as metabolically stable surrogates and photographically active systems (Schnurch et al., 2006; Crabtree, 2005; Venkatakrishnan, et al., 2000). Among them, oxadiazole compounds decorated by different groups on the 5-membered ring, such as pyridyl (Du, et al., 2009) and pyrazinyl rings, (Du, et al., 2005, 2006), also show interesting coordination behaviors. However, the related ligands involving methyl-pyrazinyl groups remain uninvestigated. They may display three typical configurations under different surroundings and multiple binding patterns (hexadentate at the most) during coordination. In this contribution, we present the crystal structure of the title compound, a bis(4-methylpyrazinyl) substituted oxadiazole. It was prepared by the reaction of 5-methylpyrazine-2-carboxylic acid and hydrazine dihydrochloride in the presence of polyphosphoric acid and anhydrous phosphorus pentoxide.

In the molecule of the title compound, Fig.1, pyrazinyl ring A [(N1,C3,C2,N2,C13,C4); planar to within 0.009 (3) Å] is inclined to pyrazinyl ring B [(N5,C9,C10,N6,C11,C9); planar to within 0.018 (3) Å] by 5.62 (15) °. They deviate from the central oxadiazole ring (planar to within 0.005 (3) Å) by 1.52 (16)° and 5.55 (17)°, respectively.

In the crystal a C—H···N interaction, involving pyrazinyl rings A and B, connect molecules to form zigzag poylmer chains propagating in [010] (Table 1 and Fig. 2).

Related literature top

For background information and applications of oxadiazole derivatives, see: Schnurch et al. (2006); Crabtree (2005); Venkatakrishnan et al. (2000). For related oxadiazole derivatives, see: Du et al. (2005, 2006, 2009).

Experimental top

5-Methylpyrazine-2-carboxylic acid (0.3 mol) and hydrazine dihydrochloride (0.2 mol) were mixed with stirring, to which polyphosphoric acid (85%, 60 ml) was added. Then, anhydrous phosphorus pentoxide (0.6 mol) was carefully added to the above mixture. The viscous solution was heated at 393 K, with stirring for ca 6 h. After cooling to room temperature, the resultant viscous liquid was poured over distilled water with stirring, dissolved, and then neutralized with sodium hydrate (3 mol/L). A large amount of orange precipitation of title compound was obtained and dried in air. Its single-crystal can be recrystallized from its methanol solution (Yield: 63%). Anal. Calc. for C12H10N6O: C, 55.69; H, 3.96; N, 33.05%. Found: C, 55.62; H, 4.01; N, 33.09%. Spectroscopic data for the title compound is given in the archived CIF.

Refinement top

All H atoms were initially located in a difference Fourier map. The C—H atoms were then constrained to an ideal geometry, and refind as riding atoms: C—H = 0.93 (CHaromatic) and 0.96 Å (CH3), with Uiso(H) = 1.2Ueq (C).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Bruker, 2007).

Figures top
[Figure 1] Fig. 1. A view of the molecular structure of the title molecule with the numbering scheme. Displacement ellipsoids are drawn at the 50%probabilit level.
[Figure 2] Fig. 2. A partial view, along the a-axis, of the crystal packing in the title compound, showing the N-H···N hydrogen-bonds [red dashed lines; see Table 1 for details; H-atoms not involved in these interactions have been omitted for clarity].
2,5-Bis(5-methylpyrazin-2-yl)-1,3,4-oxadiazole top
Crystal data top
C12H10N6OF(000) = 528
Mr = 254.26Dx = 1.418 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 460 reflections
a = 3.9084 (8) Åθ = 2.3–22.4°
b = 19.054 (4) ŵ = 0.10 mm−1
c = 16.328 (4) ÅT = 296 K
β = 101.64 (3)°BLOCK, yellow
V = 1191.0 (5) Å30.16 × 0.12 × 0.08 mm
Z = 4
Data collection top
Bruker SMART CCD area-detector
diffractometer		2108 independent reflections
Radiation source: fine-focus sealed tube1077 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.074
ϕ and ω scansθmax = 25.0°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −4→3
Tmin = 0.984, Tmax = 0.992k = −22→22
6101 measured reflectionsl = −13→19
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)] = 0.064Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.120H-atom parameters constrained
S = 1.00 w = 1/[σ2(Fo2) + (0.042P)2]
where P = (Fo2 + 2Fc2)/3
2108 reflections(Δ/σ)max < 0.001
174 parametersΔρmax = 0.15 e Å−3
0 restraintsΔρmin = −0.18 e Å−3
Crystal data top
C12H10N6OV = 1191.0 (5) Å3
Mr = 254.26Z = 4
Monoclinic, P21/cMo Kα radiation
a = 3.9084 (8) ŵ = 0.10 mm−1
b = 19.054 (4) ÅT = 296 K
c = 16.328 (4) Å0.16 × 0.12 × 0.08 mm
β = 101.64 (3)°
Data collection top
Bruker SMART CCD area-detector
diffractometer		2108 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		1077 reflections with I > 2σ(I)
Tmin = 0.984, Tmax = 0.992Rint = 0.074
6101 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0640 restraints
wR(F2) = 0.120H-atom parameters constrained
S = 1.00Δρmax = 0.15 e Å−3
2108 reflectionsΔρmin = −0.18 e Å−3
174 parameters
Special details top

Experimental. Spectroscopic data for the title compound: IR (KBr, cm-1): 3036m, 1515w, 1568w, 1461s, 1340w, 1272m, 1176m, 1092m, 1028?s, 915m, 835w, 769w, 728m, 522w.

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
O10.3651 (5)0.85150 (10)0.39441 (13)0.0419 (6)
N10.1455 (7)0.98781 (14)0.40516 (16)0.0502 (8)
N20.1510 (7)1.08251 (13)0.27453 (17)0.0457 (7)
N30.4865 (7)0.86734 (14)0.26968 (17)0.0513 (8)
N40.5726 (7)0.79743 (14)0.29485 (17)0.0511 (8)
N50.4644 (7)0.73687 (13)0.49788 (18)0.0471 (8)
N60.7282 (8)0.61027 (13)0.44708 (18)0.0503 (8)
C1−0.0765 (8)1.17661 (16)0.3485 (2)0.0551 (10)
H1A0.09611.20800.33500.083*
H1B−0.11001.18630.40410.083*
H1C−0.29321.18310.30940.083*
C20.0444 (8)1.10226 (16)0.3440 (2)0.0387 (8)
C30.0457 (8)1.05456 (17)0.4080 (2)0.0495 (9)
H3−0.02741.06990.45570.059*
C40.2502 (8)0.96885 (15)0.3355 (2)0.0386 (8)
C60.3694 (8)0.89630 (17)0.3300 (2)0.0411 (9)
C70.4940 (8)0.79085 (16)0.3676 (2)0.0403 (8)
C80.5402 (8)0.72924 (16)0.4219 (2)0.0398 (8)
C90.5263 (8)0.68055 (17)0.5472 (2)0.0485 (9)
H90.47420.68330.60020.058*
C100.6641 (8)0.61806 (17)0.5240 (2)0.0435 (9)
C110.6639 (8)0.66627 (17)0.3962 (2)0.0485 (9)
H110.70350.66270.34210.058*
C120.7464 (9)0.55814 (17)0.5838 (2)0.0644 (11)
H12A0.55150.52650.57600.097*
H12B0.79180.57570.64010.097*
H12C0.94890.53380.57370.097*
C130.2561 (8)1.01613 (17)0.2717 (2)0.0465 (9)
H130.33681.00110.22480.056*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0517 (15)0.0398 (14)0.0370 (14)−0.0001 (10)0.0157 (11)−0.0021 (11)
N10.072 (2)0.0464 (18)0.0363 (18)0.0037 (15)0.0208 (17)0.0015 (14)
N20.058 (2)0.0384 (17)0.0435 (19)−0.0050 (14)0.0157 (16)−0.0006 (14)
N30.072 (2)0.0440 (18)0.043 (2)−0.0048 (14)0.0242 (17)−0.0012 (15)
N40.071 (2)0.0427 (18)0.046 (2)−0.0013 (15)0.0256 (17)−0.0026 (15)
N50.059 (2)0.0433 (18)0.0426 (18)0.0011 (14)0.0198 (16)−0.0029 (15)
N60.062 (2)0.0465 (18)0.045 (2)0.0080 (15)0.0184 (16)−0.0027 (16)
C10.058 (3)0.047 (2)0.061 (3)−0.0026 (17)0.013 (2)−0.0034 (19)
C20.040 (2)0.041 (2)0.035 (2)−0.0037 (16)0.0081 (17)−0.0045 (17)
C30.065 (2)0.050 (2)0.038 (2)0.003 (2)0.022 (2)−0.0031 (19)
C40.043 (2)0.037 (2)0.037 (2)−0.0047 (15)0.0114 (18)−0.0020 (16)
C60.047 (2)0.043 (2)0.035 (2)−0.0105 (17)0.0138 (18)−0.0013 (17)
C70.047 (2)0.033 (2)0.041 (2)−0.0037 (16)0.0119 (18)−0.0064 (18)
C80.044 (2)0.038 (2)0.039 (2)−0.0026 (16)0.0116 (17)−0.0086 (17)
C90.061 (2)0.050 (2)0.039 (2)−0.0018 (18)0.0210 (19)−0.0048 (19)
C100.041 (2)0.047 (2)0.044 (2)−0.0004 (17)0.0124 (19)−0.0026 (18)
C110.060 (2)0.051 (2)0.038 (2)0.0036 (18)0.0179 (19)−0.0081 (18)
C120.073 (3)0.064 (3)0.058 (3)0.014 (2)0.019 (2)0.011 (2)
C130.060 (2)0.049 (2)0.035 (2)−0.0086 (18)0.0175 (19)−0.0057 (18)
Geometric parameters (Å, º) top
O1—C61.357 (3)C1—H1C0.9600
O1—C71.367 (3)C2—C31.384 (4)
N1—C31.334 (4)C3—H30.9300
N1—C41.334 (4)C4—C131.381 (4)
N2—C131.334 (4)C4—C61.467 (4)
N2—C21.339 (4)C7—C81.460 (4)
N3—C61.291 (4)C8—C111.390 (4)
N3—N41.415 (3)C9—C101.390 (4)
N4—C71.293 (4)C9—H90.9300
N5—C91.334 (4)C10—C121.494 (4)
N5—C81.340 (4)C11—H110.9300
N6—C101.338 (4)C12—H12A0.9600
N6—C111.344 (4)C12—H12B0.9600
C1—C21.500 (4)C12—H12C0.9600
C1—H1A0.9600C13—H130.9300
C1—H1B0.9600
C6—O1—C7102.8 (2)N4—C7—O1112.6 (3)
C3—N1—C4115.4 (3)N4—C7—C8127.8 (3)
C13—N2—C2116.6 (3)O1—C7—C8119.6 (3)
C6—N3—N4106.3 (2)N5—C8—C11121.9 (3)
C7—N4—N3105.8 (3)N5—C8—C7116.8 (3)
C9—N5—C8115.1 (3)C11—C8—C7121.3 (3)
C10—N6—C11116.4 (3)N5—C9—C10123.9 (3)
C2—C1—H1A109.5N5—C9—H9118.1
C2—C1—H1B109.5C10—C9—H9118.1
H1A—C1—H1B109.5N6—C10—C9120.4 (3)
C2—C1—H1C109.5N6—C10—C12118.2 (3)
H1A—C1—H1C109.5C9—C10—C12121.4 (3)
H1B—C1—H1C109.5N6—C11—C8122.1 (3)
N2—C2—C3120.0 (3)N6—C11—H11118.9
N2—C2—C1117.5 (3)C8—C11—H11118.9
C3—C2—C1122.4 (3)C10—C12—H12A109.5
N1—C3—C2123.8 (3)C10—C12—H12B109.5
N1—C3—H3118.1H12A—C12—H12B109.5
C2—C3—H3118.1C10—C12—H12C109.5
N1—C4—C13121.4 (3)H12A—C12—H12C109.5
N1—C4—C6117.6 (3)H12B—C12—H12C109.5
C13—C4—C6121.0 (3)N2—C13—C4122.7 (3)
N3—C6—O1112.6 (3)N2—C13—H13118.7
N3—C6—C4127.9 (3)C4—C13—H13118.7
O1—C6—C4119.5 (3)
C6—N3—N4—C70.9 (4)C6—O1—C7—C8178.2 (3)
C13—N2—C2—C3−0.3 (5)C9—N5—C8—C111.9 (5)
C13—N2—C2—C1−179.7 (3)C9—N5—C8—C7−176.8 (3)
C4—N1—C3—C20.5 (5)N4—C7—C8—N5174.8 (3)
N2—C2—C3—N1−0.7 (5)O1—C7—C8—N5−2.6 (4)
C1—C2—C3—N1178.7 (3)N4—C7—C8—C11−4.0 (5)
C3—N1—C4—C130.6 (5)O1—C7—C8—C11178.7 (3)
C3—N1—C4—C6178.8 (3)C8—N5—C9—C100.9 (5)
N4—N3—C6—O1−0.6 (4)C11—N6—C10—C92.3 (5)
N4—N3—C6—C4178.9 (3)C11—N6—C10—C12−177.4 (3)
C7—O1—C6—N30.1 (4)N5—C9—C10—N6−3.2 (5)
C7—O1—C6—C4−179.5 (3)N5—C9—C10—C12176.5 (3)
N1—C4—C6—N3−178.7 (3)C10—N6—C11—C80.5 (5)
C13—C4—C6—N3−0.5 (5)N5—C8—C11—N6−2.8 (5)
N1—C4—C6—O10.8 (4)C7—C8—C11—N6175.9 (3)
C13—C4—C6—O1179.0 (3)C2—N2—C13—C41.4 (5)
N3—N4—C7—O1−0.9 (4)N1—C4—C13—N2−1.7 (5)
N3—N4—C7—C8−178.4 (3)C6—C4—C13—N2−179.8 (3)
C6—O1—C7—N40.5 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···N2i0.932.593.414 (4)148
Symmetry code: (i) −x+1, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC12H10N6O
Mr254.26
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)3.9084 (8), 19.054 (4), 16.328 (4)
β (°) 101.64 (3)
V (Å3)1191.0 (5)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.16 × 0.12 × 0.08
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.984, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections		6101, 2108, 1077
Rint0.074
(sin θ/λ)max (Å−1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.120, 1.00
No. of reflections2108
No. of parameters174
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.15, −0.18

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999), SHELXTL (Bruker, 2007).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C11—H11···N2i0.932.593.414 (4)148
Symmetry code: (i) −x+1, y−1/2, −z+1/2.
 

Acknowledgements

This work was supported financially by Tianjin Normal University (grant No. 52X09004). Professor Hai-Bin Song, Department of Chemistry, Nankai University, Tianjin 300371, People's Republic of China, is thanked for the data collection.

References

First citationBrandenburg, K. (1999). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
 First citationBruker (2007). SMART, SAINT and SHELXTL. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationCrabtree, R. H. (2005). J. Organomet. Chem. 690, 5451–5457.  Web of Science CrossRef CAS Google Scholar
 First citationDu, M. & Bu, X. H. (2009). Bull. Chem. Soc. Jpn, 82, 539–554.  CrossRef CAS Google Scholar
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ISSN: 2056-9890
Volume 67| Part 6| June 2011| Page o1416
doi:10.1107/S1600536811015029
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