2,5-Dimethyl­pyrazine 1,4-dioxide

Brown, C.J.; Knaust, J.M.

doi:10.1107/S1600536809046741

organic compounds

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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3052

doi:10.1107/S1600536809046741

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2,5-Dimethylpyrazine 1,4-dioxide

Carlton J. Brown III ^a and Jacqueline M. Knaust ^a ^*

^aAllegheny College, Chemistry Department, 520 North Main St., Meadville, PA 16335, USA
^*Correspondence e-mail: jknaust@allegheny.edu

(Received 4 November 2009; accepted 5 November 2009; online 11 November 2009)

The title compound, C₆H₈N₂O₂, was prepared from 2,5-dimethylpyrazine, acetic acid, and hydrogen peroxide. The 2,5-dimethylpyrazine 1,4-dioxide molecule is located on an inversion center. π–π interactions between neighboring 2,5-dimethylpyrazine 1,4-dioxide molecules are observed with an interplanar distance of 3.191 Å. Each 2,5-dimethylpyrazine 1,4-dioxide molecule is linked to four neighboring N-oxide molecules through C—H⋯O hydrogen-bonding interactions, forming two-dimensional layers.

Related literature

For the synthesis of 2,2′-bipyridine N,N′-dioxide, see: Simpson et al. (1963 ). For the synthesis of lanthanide coordination networks with pyrazine N,N′-dioxide, see: Cardoso et al. (2001 ); Sun et al. (2004 ). For the use of 2,5-dimethylpyrazine 1,4-dioxide in the synthesis of transition metal coordination networks, see: Shi, Sun et al. (2006 ); Shi, Zhang et al. (2006 ); Shi et al. (2007 ); Sun, Gao et al. (2005 ); Sun, Wang et al. (2005 ). For related structures, see: Näther et al. (2002 ); Gratton & Knaust (2009 ).

Experimental

Crystal data

C₆H₈N₂O₂
M_r = 140.14
Monoclinic, P 2₁ /c
a = 3.9971 (8) Å
b = 8.9176 (17) Å
c = 8.9249 (17) Å
β = 102.205 (3)°
V = 310.93 (10) Å³
Z = 2
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 173 K
0.45 × 0.12 × 0.11 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ) T_min = 0.623, T_max = 0.746
2388 measured reflections
965 independent reflections
811 reflections with I > 2σ(I)
R_int = 0.023

Refinement

R[F² > 2σ(F²)] = 0.049
wR(F²) = 0.144
S = 1.07
965 reflections
47 parameters
H-atom parameters constrained
Δρ_max = 0.62 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1C⋯O1ⁱ	0.98	2.41	3.3290 (15)	155
C3—H3⋯O1ⁱ	0.95	2.31	3.1863 (15)	153
Symmetry code: (i) $[x+1, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2007 ); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: X-SEED.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809046741/zl2251sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809046741/zl2251Isup2.hkl

checkCIF report

Comment top

The use of pyrazine N,N'-dioxide in the synthesis of lanthanide coordination networks has been of recent interest (Cardoso et al. (2001), and Sun et al. (2004)). Shi, Sun et al. (2006), Shi, Zhang et al. (2006), Shi et al. (2007), Sun, Gao et al. (2005), and Sun, Wang et al. (2005) recently reported the use 2,5-dimethylpyrazine 1,4-dioxide in the synthesis of a transition metal coordination networks. The title compound was prepared using the reaction conditions described by Simpson et al. (1963) to prepare 2,2'-bipyridine N,N'-dioxide.

The asymmetric unit of the title compound contains half of a 2,5-dimethylpyrazine 1,4-dioxide molecule (Figure 1) and the N-oxide molecule lies on an inversion center. π-Cloud interactions between neighboring 2,5-dimethylpyrazine 1,4-dioxide molecules are observed with an interplanar distance of 3.191 Å (Figure 2); there is a slippage of 2.408 Å such that N1ⁱⁱⁱ on the neighboring N-oxide molecule lies directly over the centroid of the C3—N1ⁱ bond [symmetry codes: (i) -x + 1, -y, -z + 1; (iii) x + 1, y, z] (Figure 3). The title compound forms eight C—H···O hydrogen bonds with four neighboring N-oxide molecules, and these hydrogen bonding interactions result in the formation of two-dimensional layers (Figure 5); whereas in the related structures of 2-methylpyrazine 1,4-dioxide and pyrazine N,N'-dioxide, the N-oxide molecules form hydrogen bonded ribbons and a three-dimensional network, respectively (Gratton et al. (2009), Näther et al. (2002)). A packing diagram of the title compound is given in Figure 5.

Related literature top

For the synthesis of 2,2'-bipyridine N,N'-dioxide, see: Simpson et al. (1963). For the synthesis of lanthanide coordination networks with pyrazine N,N'-dioxide, see: Cardoso et al. (2001); Sun et al. (2004). For the use of 2,5-dimethylpyrazine 1,4-dioxide in the synthesis of transition metal coordination networks, see: Shi, Sun et al. (2006); Shi, Zhang et al. (2006); Shi et al. (2007); Sun, Gao et al. (2005); Sun, Wang et al. (2005). For related structures, see: Näther et al. (2002); Gratton et al. (2009).

Experimental top

2,5-Dimethylpyrazine (6.99 ml, 64.0 mmol), acetic acid (75 ml), and 30% hydrogen peroxide (13 ml) were heated at 343–353 K for 3 h. Additional hydrogen peroxide (9 ml) was added, and heating was continued. After an additional 19 h of heating the solution was cooled to room temperature. Crystals formed upon the addition of acetone (1L) and cooling to 273 K, and were recrystallized from hot water by addition of excess acetone and cooling to 273 K.

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT-Plus (Bruker, 2007); data reduction: SAINT-Plus (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: X-SEED (Barbour, 2001).

Figures top

	Fig. 1. The molecular structure of the title compound with atom labels and 50% probability displacement ellipsoids for non-H atoms. Atoms not labeled are generated by the symmetry operator (i) -x + 1,-y, -z + 1.
	Fig. 2. Space filling representation of the π-cloud interactions between neighboring 2,5-dimethylpyrazine 1,4-dioxide molecules.
	Fig. 3. Ball and stick representation of the π-cloud interactions between neighboring 2,5-diethylpyrazine 1,4-dioxide molecules. symmetry codes: (i) -x + 1, -y, -z + 1; (iii) x + 1, y, z; (iv) -x + 2, -y, -z + 1
	Fig. 4. C—H···O hydrogen bonding interactions between neighboring 2,5-dimethylpyrazine 1,4-dioxide molecules. Hydrogen bonds are shown as dashed lines. Symmetry code: (ii) x + 1, -y + 1/2, z +1 /2.
	Fig. 5. Packing of the title compound viewed down the b axis. Hydrogen bonds are shown as dashed red lines, and π-cloud interactions are shown as dashed blue lines.

2,5-Dimethylpyrazine 1,4-dioxide top

Crystal data top

C₆H₈N₂O₂	F(000) = 148
M_r = 140.14	D_x = 1.497 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 958 reflections
a = 3.9971 (8) Å	θ = 3.3–31.5°
b = 8.9176 (17) Å	µ = 0.12 mm⁻¹
c = 8.9249 (17) Å	T = 173 K
β = 102.205 (3)°	Rod, colorless
V = 310.93 (10) Å³	0.45 × 0.12 × 0.11 mm
Z = 2

Data collection top

Bruker SMART APEX CCD diffractometer	965 independent reflections
Radiation source: fine-focus sealed tube	811 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.023
ω scans	θ_max = 31.5°, θ_min = 3.3°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −5→5
T_min = 0.623, T_max = 0.746	k = −12→9
2388 measured reflections	l = −12→8

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.144	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0934P)² + 0.0493P] where P = (F_o² + 2F_c²)/3
965 reflections	(Δ/σ)_max < 0.001
47 parameters	Δρ_max = 0.62 e Å⁻³
0 restraints	Δρ_min = −0.34 e Å⁻³

Crystal data top

C₆H₈N₂O₂	V = 310.93 (10) Å³
M_r = 140.14	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 3.9971 (8) Å	µ = 0.12 mm⁻¹
b = 8.9176 (17) Å	T = 173 K
c = 8.9249 (17) Å	0.45 × 0.12 × 0.11 mm
β = 102.205 (3)°

Data collection top

Bruker SMART APEX CCD diffractometer	965 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2001)	811 reflections with I > 2σ(I)
T_min = 0.623, T_max = 0.746	R_int = 0.023
2388 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.049	0 restraints
wR(F²) = 0.144	H-atom parameters constrained
S = 1.07	Δρ_max = 0.62 e Å⁻³
965 reflections	Δρ_min = −0.34 e Å⁻³
47 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.

Highest peak 0.62 at 0.4105 0.2353 0.4867 [0.74 A from C1] Deepest hole -0.34 at 0.1454 0.0185 0.3480 [0.59 A from N1]

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

	x	y	z	U_iso*/U_eq
O1	−0.0014 (2)	0.11342 (10)	0.28187 (10)	0.0190 (3)
N1	0.2436 (2)	0.05941 (11)	0.38743 (11)	0.0141 (3)
C1	0.3636 (3)	0.31533 (12)	0.48341 (15)	0.0182 (3)
H1A	0.1286	0.3338	0.4948	0.027*
H1B	0.3910	0.3522	0.3832	0.027*
H1C	0.5238	0.3680	0.5647	0.027*
C2	0.4355 (3)	0.15172 (13)	0.49468 (13)	0.0145 (3)
C3	0.6882 (3)	0.09028 (12)	0.60638 (14)	0.0146 (3)
H3	0.8194	0.1543	0.6816	0.017*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0183 (4)	0.0186 (5)	0.0151 (5)	0.0029 (3)	−0.0081 (3)	0.0031 (3)
N1	0.0137 (4)	0.0150 (5)	0.0112 (5)	0.0004 (3)	−0.0028 (4)	0.0019 (4)
C1	0.0204 (5)	0.0122 (5)	0.0191 (6)	0.0012 (4)	−0.0022 (4)	0.0010 (4)
C2	0.0155 (5)	0.0136 (5)	0.0130 (5)	−0.0012 (4)	−0.0002 (4)	−0.0002 (4)
C3	0.0157 (5)	0.0134 (5)	0.0126 (5)	−0.0006 (4)	−0.0012 (4)	−0.0001 (4)

Geometric parameters (Å, º) top

O1—N1	1.2996 (12)	C1—H1B	0.9800
N1—C3ⁱ	1.3611 (14)	C1—H1C	0.9800
N1—C2	1.3681 (15)	C2—C3	1.3744 (15)
C1—C2	1.4863 (15)	C3—H3	0.9500
C1—H1A	0.9800

O1—N1—C3ⁱ	120.44 (10)	H1B—C1—H1C	109.5
O1—N1—C2	120.62 (10)	N1—C2—C3	119.01 (10)
C3ⁱ—N1—C2	118.94 (10)	N1—C2—C1	118.14 (10)
C2—C1—H1A	109.5	C3—C2—C1	122.85 (10)
C2—C1—H1B	109.5	N1ⁱ—C3—C2	122.05 (10)
H1A—C1—H1B	109.5	N1ⁱ—C3—H3	119.0
C2—C1—H1C	109.5	C2—C3—H3	119.0
H1A—C1—H1C	109.5

Symmetry code: (i) −x+1, −y, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1C···O1ⁱⁱ	0.98	2.41	3.3290 (15)	155
C3—H3···O1ⁱⁱ	0.95	2.31	3.1863 (15)	153

Symmetry code: (ii) x+1, −y+1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₆H₈N₂O₂
M_r	140.14
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	3.9971 (8), 8.9176 (17), 8.9249 (17)
β (°)	102.205 (3)
V (Å³)	310.93 (10)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.45 × 0.12 × 0.11

Data collection
Diffractometer	Bruker SMART APEX CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2001)
T_min, T_max	0.623, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	2388, 965, 811
R_int	0.023
(sin θ/λ)_max (Å⁻¹)	0.735

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.144, 1.07
No. of reflections	965
No. of parameters	47
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.62, −0.34

Computer programs: SMART (Bruker, 2007), SAINT-Plus (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1C···O1ⁱ	0.98	2.41	3.3290 (15)	155.1
C3—H3···O1ⁱ	0.95	2.31	3.1863 (15)	153.1

Symmetry code: (i) x+1, −y+1/2, z+1/2.

Acknowledgements

The authors are grateful to Allegheny College for providing funding in support of this research. The diffractometer was funded by the NSF (grant No. 0087210), the Ohio Board of Regents (grant No. CAP-491) and by Youngstown State University. The authors would also like to acknowledge the STaRBURSTT CyberInstrumentation Consortium for assistance with the crystallography.

References

Barbour, L. J. (2001). J. Supramol. Chem. 1, 189–191. CrossRef CAS Google Scholar
Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2007). SMART and SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cardoso, M. C. C., Zinner, L. B., Zukerman-Scheptor, J., Araújo Melo, D. M. & Vincentini, G. J. (2001). J. Alloys Compd, 323–324, 22–25. Web of Science CSD CrossRef CAS Google Scholar
Gratton, J. L. & Knaust, J. M. (2009). Acta Cryst. E65, o3040. Web of Science CSD CrossRef IUCr Journals Google Scholar
Näther, C., Kowallik, P. & Jess, I. (2002). Acta Cryst. E58, o1253–o1254. Web of Science CSD CrossRef IUCr Journals Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Shi, J. M., Sun, Y. M., Zhang, X., Yi, L., Cheng, P. & Liu, L. D. (2006). J. Phys. Chem. A, 110, 7677–7681. Web of Science CSD CrossRef PubMed CAS Google Scholar
Shi, J. M., Zhang, X., Wu, C. J. & Liu, L. D. (2006). Pol. J. Chem. 80, 2063–2068. CAS Google Scholar
Shi, J. M., Zhang, X., Xu, H. Y., Wu, C. W. & Liu, L. D. (2007). J. Coord. Chem. 60, 647–654. Web of Science CSD CrossRef CAS Google Scholar
Simpson, P. G., Vinciguerra, A. & Quagliano, J. V. (1963). Inorg. Chem. 2, 282–286. CrossRef CAS Web of Science Google Scholar
Sun, H. L., Gao, S., Ma, B. Q., Chang, F. & Fu, W. F. (2004). Microporous Mesoporous Mater. 73 89–95. Google Scholar
Sun, H. L., Gao, S., Ma, B. Q., Su, G. & Batten, S. R. (2005). Cryst. Growth Des. 5, 269–277. Web of Science CSD CrossRef CAS Google Scholar
Sun, H. L., Wang, Z. M. & Gao, S. (2005). Inorg. Chem. 44, 2169–2176. Web of Science CSD CrossRef PubMed CAS Google Scholar