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

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ISSN: 2056-9890

Diiso­propyl pyrazine-2,5-di­carboxyl­ate

aCollege of Materials Science and Engineering, Huaqiao University, Xiamen, Fujian, 361021, People's Republic of China
*Correspondence e-mail: wws@hqu.edu.cn

(Received 19 June 2010; accepted 22 July 2010; online 4 August 2010)

The mol­ecule of the title compound, C12H16N2O4, is located on an inversion center. The carboxyl­ate groups are twisted slightly with respect to the pyrazine ring, making a dihedral angle of 6.4 (3)°.

Related literature

For related structures, see: Cockriel et al. (2008[Cockriel, D. L., McClain, J. M., Patel, K. C., Ullom, R., Hasley, T. R., Archibald, S. J. & Hubin, T. J. (2008). Inorg. Chem. Commun. 11, 1-4.]); Vishweshwar et al. (2004[Vishweshwar, P., Babu, N. J., Nangia, A., Mason, S. A., Puschmann, H., Mondal, R. & Howard, J. A. K. (2004). J. Phys. Chem. A, 108, 9406-9416.]).

[Scheme 1]

Experimental

Crystal data
  • C12H16N2O4

  • Mr = 252.27

  • Monoclinic, P 21 /c

  • a = 4.7804 (1) Å

  • b = 15.6842 (3) Å

  • c = 9.1877 (2) Å

  • β = 104.227 (2)°

  • V = 667.74 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 296 K

  • 0.44 × 0.20 × 0.09 mm

Data collection
  • Bruker P4 diffractometer

  • 10015 measured reflections

  • 1361 independent reflections

  • 969 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.148

  • S = 1.07

  • 1361 reflections

  • 84 parameters

  • H-atom parameters constrained

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.16 e Å−3

Data collection: XSCANS (Bruker, 1999[Bruker (1999). XSCANS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: XSCANS; data reduction: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); 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; software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

The molecule of the title compound is is organized around inversion center (Fig. 1). The carboxylate group are slightly twisted with respect to the pyrazine ring making a dihedral angle of 6.4 (3)°.The carboxyl C—O and C O bonds are normal, while the bond angle of C—NC are slightly smaller than those in pyrazine-2,5-dicarboxylic acid dihydrate (Vishweshwar et al.,2004). The angle C3—O1—C4 of 117.60 (14) is larger compared to the value of 115.04 (16) in Pyrazine-2,5-dicarboxylic acid dimethyl ester (Cockriel et al., 2008). The atoms of O(1) to C(5) may be considered to control the molecular packing through intermolecular hydrophobic interaction of the isopropyl groups. The crystal structure is stabilized via van der Waals forces.

Related literature top

For related structures, see: Cockriel et al. (2008); Vishweshwar et al. (2004).

Experimental top

The title compound was synthesized by dissolving 2,5-pyrazinedicarboxylic acid (200 mg,11.9 mmol)in 200 ml 2-propanol, while stirring 2 ml concentrated H2SO4 was added slowly.The solution was left to reflux for 12 h, then distillation under reduced pressure until no solution to outflow after filtered.The solution was made neutral with Na2CO3(aq), extracted with 30 ml e thyl acetate.Orange crystals of the title compound would be grew by slow evaporating at room temperature after five days.

Refinement top

The C-bound H atoms were included in the riding model approximation with C—H=0.93, all these H atoms included in the final refinement. The Uiso of each H atom = 1.2Ueq(C). The Ueq of C4 is regular. The checkcif considers the Ueq of C4 is low, this is because it is lower compared with the C5 and C6.

Structure description top

The molecule of the title compound is is organized around inversion center (Fig. 1). The carboxylate group are slightly twisted with respect to the pyrazine ring making a dihedral angle of 6.4 (3)°.The carboxyl C—O and C O bonds are normal, while the bond angle of C—NC are slightly smaller than those in pyrazine-2,5-dicarboxylic acid dihydrate (Vishweshwar et al.,2004). The angle C3—O1—C4 of 117.60 (14) is larger compared to the value of 115.04 (16) in Pyrazine-2,5-dicarboxylic acid dimethyl ester (Cockriel et al., 2008). The atoms of O(1) to C(5) may be considered to control the molecular packing through intermolecular hydrophobic interaction of the isopropyl groups. The crystal structure is stabilized via van der Waals forces.

For related structures, see: Cockriel et al. (2008); Vishweshwar et al. (2004).

Computing details top

Data collection: XSCANS (Bruker, 1999); cell refinement: XSCANS (Bruker, 1999; data reduction: SHELXTL (Sheldrick, 2008); 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. Molecular view of the title compound with the atom labeling scheme. Ellipsoids are drawn at the 30% probability level. [Symmetry code: (A) -x+1, -y+1, -z+1].
Diisopropyl pyrazine-2,5-dicarboxylate top
Crystal data top
C12H16N2O4F(000) = 268
Mr = 252.27Dx = 1.255 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1552 reflections
a = 4.7804 (1) Åθ = 2.6–27.7°
b = 15.6842 (3) ŵ = 0.10 mm1
c = 9.1877 (2) ÅT = 296 K
β = 104.227 (2)°Block, orange
V = 667.74 (2) Å30.44 × 0.20 × 0.09 mm
Z = 2
Data collection top
Bruker P4
diffractometer
969 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.028
Graphite monochromatorθmax = 26.4°, θmin = 2.6°
Detector resolution: 0 pixels mm-1h = 55
ω scansk = 019
10015 measured reflectionsl = 011
1361 independent reflections
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.148H-atom parameters constrained
S = 1.07 w = 1/[σ2(Fo2) + (0.0658P)2 + 0.1415P]
where P = (Fo2 + 2Fc2)/3
1361 reflections(Δ/σ)max < 0.001
84 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.16 e Å3
Crystal data top
C12H16N2O4V = 667.74 (2) Å3
Mr = 252.27Z = 2
Monoclinic, P21/cMo Kα radiation
a = 4.7804 (1) ŵ = 0.10 mm1
b = 15.6842 (3) ÅT = 296 K
c = 9.1877 (2) Å0.44 × 0.20 × 0.09 mm
β = 104.227 (2)°
Data collection top
Bruker P4
diffractometer
969 reflections with I > 2σ(I)
10015 measured reflectionsRint = 0.028
1361 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.148H-atom parameters constrained
S = 1.07Δρmax = 0.22 e Å3
1361 reflectionsΔρmin = 0.16 e Å3
84 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
O10.2207 (3)0.61807 (8)0.76556 (16)0.0760 (5)
O20.0875 (4)0.48234 (10)0.7742 (2)0.0932 (6)
N10.4741 (4)0.58450 (9)0.54265 (18)0.0671 (5)
C10.3667 (4)0.52028 (10)0.6052 (2)0.0563 (5)
C20.6071 (4)0.56289 (12)0.4371 (2)0.0683 (5)
H2A0.68580.60580.38980.082*
C30.2104 (4)0.53794 (12)0.7251 (2)0.0625 (5)
C40.0807 (5)0.64177 (14)0.8860 (2)0.0803 (6)
H4A0.07480.60110.88640.096*
C50.0461 (8)0.72695 (18)0.8468 (4)0.1229 (11)
H5A0.14750.74430.92000.184*
H5B0.17810.72490.74940.184*
H5C0.10460.76720.84540.184*
C60.2971 (8)0.6359 (3)1.0299 (3)0.1457 (15)
H6A0.20500.64371.11080.219*
H6B0.44030.67951.03460.219*
H6C0.38770.58091.03840.219*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0981 (11)0.0603 (8)0.0829 (9)0.0050 (7)0.0476 (8)0.0104 (6)
O20.1167 (13)0.0701 (9)0.1115 (13)0.0127 (8)0.0640 (11)0.0055 (8)
N10.0815 (11)0.0508 (8)0.0747 (10)0.0003 (7)0.0303 (8)0.0029 (7)
C10.0563 (10)0.0523 (9)0.0600 (10)0.0013 (7)0.0139 (8)0.0013 (7)
C20.0830 (13)0.0535 (10)0.0758 (12)0.0043 (9)0.0334 (11)0.0006 (9)
C30.0650 (11)0.0580 (10)0.0671 (11)0.0028 (8)0.0209 (9)0.0002 (8)
C40.1000 (16)0.0706 (12)0.0855 (15)0.0042 (11)0.0519 (13)0.0096 (10)
C50.173 (3)0.0914 (18)0.124 (2)0.0344 (19)0.075 (2)0.0047 (16)
C60.141 (3)0.231 (4)0.0736 (17)0.040 (3)0.0424 (18)0.000 (2)
Geometric parameters (Å, º) top
O1—C31.308 (2)C4—C51.475 (4)
O1—C41.474 (2)C4—H4A0.9800
O2—C31.200 (2)C5—H5A0.9600
N1—C11.324 (2)C5—H5B0.9600
N1—C21.327 (2)C5—H5C0.9600
C1—C2i1.376 (2)C6—H6A0.9600
C1—C31.500 (3)C6—H6B0.9600
C2—H2A0.9300C6—H6C0.9600
C4—C61.468 (4)
C3—O1—C4117.61 (15)O1—C4—H4A108.9
C1—N1—C2115.43 (15)C5—C4—H4A108.9
N1—C1—C2i121.76 (17)C4—C5—H5A109.5
N1—C1—C3119.62 (15)C4—C5—H5B109.5
C2i—C1—C3118.62 (16)H5A—C5—H5B109.5
N1—C2—C1i122.82 (17)C4—C5—H5C109.5
N1—C2—H2A118.6H5A—C5—H5C109.5
C1i—C2—H2A118.6H5B—C5—H5C109.5
O2—C3—O1125.35 (18)C4—C6—H6A109.5
O2—C3—C1121.35 (17)C4—C6—H6B109.5
O1—C3—C1113.29 (16)H6A—C6—H6B109.5
C6—C4—O1108.1 (2)C4—C6—H6C109.5
C6—C4—C5115.6 (3)H6A—C6—H6C109.5
O1—C4—C5106.28 (18)H6B—C6—H6C109.5
C6—C4—H4A108.9
N1—C1—C3—O16.0 (3)
Symmetry code: (i) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC12H16N2O4
Mr252.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)4.7804 (1), 15.6842 (3), 9.1877 (2)
β (°) 104.227 (2)
V3)667.74 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.44 × 0.20 × 0.09
Data collection
DiffractometerBruker P4
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
10015, 1361, 969
Rint0.028
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.148, 1.07
No. of reflections1361
No. of parameters84
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.22, 0.16

Computer programs: XSCANS (Bruker, 1999), XSCANS (Bruker, 1999, SHELXTL (Sheldrick, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008).

 

Acknowledgements

We are grateful for financial support from the National Science Foundation of Fujian Province of China (No. E0610017, 2003 F006).

References

First citationBruker (1999). XSCANS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationCockriel, D. L., McClain, J. M., Patel, K. C., Ullom, R., Hasley, T. R., Archibald, S. J. & Hubin, T. J. (2008). Inorg. Chem. Commun. 11, 1–4.  Web of Science CSD CrossRef CAS Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationVishweshwar, P., Babu, N. J., Nangia, A., Mason, S. A., Puschmann, H., Mondal, R. & Howard, J. A. K. (2004). J. Phys. Chem. A, 108, 9406–9416.  Web of Science CSD CrossRef CAS Google Scholar

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ISSN: 2056-9890
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