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Acta Crystallogr Sect E Struct Rep Online. 2010 August 1; 66(Pt 8): o1913.
Published online 2010 July 3. doi:  10.1107/S1600536810025067
PMCID: PMC3007508

4,6-Dimeth­oxy-2-(methyl­sulfon­yl)pyrimidine

Abstract

The asymmetric unit of the title compound, C7H10N2O4S, comprises of two independent mol­ecules (A and B) which differ in the orientation of the methyl­sulfonyl group [C—S—C—N = 157.98 (13)° in mol­ecule A and 6.09 (18)° in mol­ecule B]. In the crystal structure, mol­ecules of type A are linked into chains along the a axis by inter­molecular C—H(...)O hydrogen bonds. The B mol­ecules are linked to these chains by C—H(...)O hydrogen bonds.

Related literature

For general background and applications of 4,6-dimeth­oxy­pyrimidin-2-yl derivatives, see: Xi et al. (2006 [triangle]); He et al. (2007 [triangle]); Li et al. (2006 [triangle]); Gerorge (1983 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o1913-scheme1.jpg

Experimental

Crystal data

  • C7H10N2O4S
  • M r = 218.23
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o1913-efi1.jpg
  • a = 8.349 (2) Å
  • b = 11.067 (3) Å
  • c = 11.438 (3) Å
  • α = 108.457 (8)°
  • β = 92.774 (8)°
  • γ = 98.504 (8)°
  • V = 986.4 (4) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.32 mm−1
  • T = 296 K
  • 0.38 × 0.30 × 0.08 mm

Data collection

  • Bruker APEXII DUO CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 2009 [triangle]) T min = 0.889, T max = 0.974
  • 29277 measured reflections
  • 7063 independent reflections
  • 4866 reflections with I > 2σ(I)
  • R int = 0.042

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.156
  • S = 1.08
  • 7063 reflections
  • 259 parameters
  • H-atom parameters constrained
  • Δρmax = 0.50 e Å−3
  • Δρmin = −0.50 e Å−3

Data collection: APEX2 (Bruker, 2009 [triangle]); cell refinement: SAINT (Bruker, 2009 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810025067/ci5121sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810025067/ci5121Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

HKF and CSY thank Universiti Sains Malaysia (USM) for the Research University Golden Goose Grant (No. 1001/PFIZIK/811012). CSY also thanks USM for the award of a USM Fellowship. AMI is grateful to the Head of the Department of Chemistry and the Director, National Institute of Technology-Karnataka, India, for providing research facilities and for their encouragement. AMI is also thankful to USM for the partial sponsorship of his visit to the X-ray Crystallography Unit, School fo Physics, USM.

supplementary crystallographic information

Comment

Compounds containing 4,6-dimethoxypyrimidin-2-yl moieties display excellent herbicidal activity (Xi et al., 2006). Most sulfonylurea herbicides and all pyrimidinylbenzoate herbicides (He et al., 2007), such as nicofulfuron, amidosulfuron, halopyrazosulfuron, ethoxysulfuron, pyriminobac-methyl and pyriftalid, possess 4,6-dimethoxypyrimidin-2-yl groups (Li et al., 2006), while sulfometuron-methyl, a kind of sulfonylurea, contains a 4,6-dimethylpyrimidin-2-yl group, which suggests that the two disubstituted pyrimidin- 2-yl groups possess high biological activity (Gerorge, 1983).

There are two molecules, A and B, in the asymmetric unit (Fig. 1) of the title compound. The molecules A and B differ in the orientation of the methylsulfonyl group [C7A—S1A—C1A—N1A = 157.98 (13)° and C7B—S1B—C1B—N2B = 6.09 (18)°]

In the crystal structure, the A molecules are linked into chains along a axis by intermolecular C3A—H3AA···O2A and C7A—H7AA···O4A hydrogen bonds. The B molecules are linked to these chains by intermolecular C5A—H5AC···O2B hydrogen bonds.

Experimental

Periodic acid (2.63 mmol, 600 mg) was dissolved in acetonitrile (6 ml) by stirring at room temperature for 1 h. To this solution, chromium trioxide (0.125 mmol, 12.5 mg) was added and stirred for 5 min to give a clear orange solution. H5IO6/CrO3 solution (1.7 ml) was added to a solution of 4,6-dimethoxy-2-methylmercaptopyrimidine (0.23 mmol) in ethyl acetate and was stirred at room temperature for 30 min. The reaction mixture was quenched with saturated sodium sulphite and was loaded on to a silica column. The column was eluted with acetone to obtain 4,6-dimethoxy-2-methylsulfonylpyrimidine. Single crystals were recrystallized from an dichloromethane solution (yield: 87%, m.p. 402–405 K).

Refinement

All H atoms were positioned geometrically [C–H = 0.93 or 0.96 Å] and refined using a riding model, with Uiso(H) = 1.2 or 1.5Ueq(C). A rotating-group model was applied for the methyl groups.

Figures

Fig. 1.
The two independent molecules of the title compound with atom labels and 30% probability displacement ellipsoids for non-H atoms.
Fig. 2.
The crystal packing of title compound, viewed down the b axis showing chains along the a axis.

Crystal data

C7H10N2O4SZ = 4
Mr = 218.23F(000) = 456
Triclinic, P1Dx = 1.470 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.349 (2) ÅCell parameters from 8362 reflections
b = 11.067 (3) Åθ = 2.2–32.1°
c = 11.438 (3) ŵ = 0.32 mm1
α = 108.457 (8)°T = 296 K
β = 92.774 (8)°Plate, colourless
γ = 98.504 (8)°0.38 × 0.30 × 0.08 mm
V = 986.4 (4) Å3

Data collection

Bruker APEXII DUO CCD area-detector diffractometer7063 independent reflections
Radiation source: fine-focus sealed tube4866 reflections with I > 2σ(I)
graphiteRint = 0.042
[var phi] and ω scansθmax = 32.5°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2009)h = −12→12
Tmin = 0.889, Tmax = 0.974k = −16→16
29277 measured reflectionsl = −17→16

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.156H-atom parameters constrained
S = 1.08w = 1/[σ2(Fo2) + (0.0771P)2 + 0.1962P] where P = (Fo2 + 2Fc2)/3
7063 reflections(Δ/σ)max = 0.001
259 parametersΔρmax = 0.50 e Å3
0 restraintsΔρmin = −0.50 e Å3

Special details

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)

xyzUiso*/Ueq
S1A−0.01034 (4)0.04422 (4)0.19330 (4)0.03856 (12)
O1A−0.02361 (19)0.10070 (16)0.32304 (15)0.0632 (4)
O2A−0.08995 (15)0.09457 (13)0.10934 (15)0.0518 (3)
O3A0.50597 (16)0.29863 (13)0.14202 (15)0.0528 (3)
O4A0.51835 (16)−0.11116 (13)0.16945 (16)0.0543 (3)
N1A0.26662 (16)0.17382 (13)0.16027 (13)0.0362 (3)
N2A0.27464 (15)−0.03547 (13)0.17789 (13)0.0364 (3)
C1A0.20400 (17)0.06224 (14)0.17287 (14)0.0334 (3)
C2A0.43408 (19)−0.01755 (16)0.16718 (16)0.0386 (3)
C3A0.51867 (19)0.09495 (18)0.15559 (17)0.0435 (4)
H3AA0.63040.10680.15020.052*
C4A0.42742 (19)0.18858 (16)0.15246 (15)0.0378 (3)
C5A0.4131 (3)0.3951 (2)0.1326 (3)0.0608 (5)
H5AA0.48380.46530.11940.091*
H5AB0.36350.42680.20780.091*
H5AC0.33000.35770.06420.091*
C6A0.4289 (3)−0.2300 (2)0.1768 (3)0.0630 (6)
H6AA0.5032−0.28720.18140.095*
H6AB0.3525−0.27040.10450.095*
H6AC0.3714−0.21160.24940.095*
C7A−0.0758 (2)−0.12239 (17)0.1485 (2)0.0476 (4)
H7AA−0.1909−0.14000.15360.071*
H7AB−0.0197−0.15710.20240.071*
H7AC−0.0529−0.16180.06480.071*
S1B0.91824 (6)0.54889 (4)0.18573 (4)0.04122 (12)
O1B1.0732 (2)0.63051 (15)0.21079 (16)0.0655 (4)
O2B0.8041 (2)0.56321 (17)0.09628 (13)0.0639 (4)
O3B0.7212 (2)0.42513 (15)0.54172 (14)0.0673 (5)
O4B0.6688 (2)0.83263 (14)0.52687 (15)0.0629 (4)
N1B0.78624 (19)0.69578 (14)0.36974 (14)0.0437 (3)
N2B0.81160 (19)0.48548 (14)0.37722 (13)0.0414 (3)
C1B0.8263 (2)0.57971 (16)0.32927 (15)0.0382 (3)
C2B0.7173 (2)0.71868 (18)0.47615 (17)0.0471 (4)
C3B0.6896 (3)0.6287 (2)0.53590 (18)0.0574 (5)
H3BA0.63830.64540.60840.069*
C4B0.7415 (3)0.51237 (18)0.48331 (17)0.0479 (4)
C5B0.7711 (4)0.3023 (2)0.4853 (2)0.0658 (6)
H5BA0.77100.25640.54380.099*
H5BB0.87870.31630.46070.099*
H5BC0.69670.25250.41380.099*
C6B0.7263 (4)0.9364 (2)0.4804 (2)0.0717 (7)
H6BA0.70751.01680.53700.108*
H6BB0.66890.92100.40090.108*
H6BC0.84080.94060.47250.108*
C7B0.9425 (3)0.38667 (19)0.1441 (2)0.0596 (6)
H7BA0.98600.36200.06550.089*
H7BB0.83890.33320.13840.089*
H7BC1.01600.37580.20580.089*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S1A0.02471 (18)0.03529 (19)0.0583 (3)0.00757 (13)0.01261 (15)0.01667 (17)
O1A0.0498 (8)0.0687 (9)0.0636 (9)0.0117 (7)0.0238 (7)0.0079 (7)
O2A0.0291 (6)0.0482 (7)0.0888 (10)0.0116 (5)0.0074 (6)0.0351 (7)
O3A0.0338 (6)0.0503 (7)0.0794 (10)−0.0034 (5)0.0040 (6)0.0332 (7)
O4A0.0313 (6)0.0516 (7)0.0890 (10)0.0153 (5)0.0114 (6)0.0311 (7)
N1A0.0264 (6)0.0368 (6)0.0450 (7)0.0026 (5)0.0036 (5)0.0143 (5)
N2A0.0255 (6)0.0385 (6)0.0472 (7)0.0077 (5)0.0063 (5)0.0156 (6)
C1A0.0226 (6)0.0364 (7)0.0410 (8)0.0041 (5)0.0052 (5)0.0126 (6)
C2A0.0265 (7)0.0440 (8)0.0473 (9)0.0093 (6)0.0055 (6)0.0159 (7)
C3A0.0235 (7)0.0518 (9)0.0575 (10)0.0048 (6)0.0060 (6)0.0216 (8)
C4A0.0283 (7)0.0419 (8)0.0433 (8)0.0003 (6)0.0034 (6)0.0167 (6)
C5A0.0500 (11)0.0536 (11)0.0890 (16)0.0007 (9)0.0077 (10)0.0411 (11)
C6A0.0476 (11)0.0511 (11)0.1001 (18)0.0169 (9)0.0138 (11)0.0339 (11)
C7A0.0319 (8)0.0385 (8)0.0761 (13)0.0027 (6)0.0102 (8)0.0249 (8)
S1B0.0485 (2)0.0379 (2)0.0431 (2)0.01011 (16)0.01501 (17)0.01859 (16)
O1B0.0583 (9)0.0610 (9)0.0768 (10)−0.0036 (7)0.0250 (8)0.0258 (8)
O2B0.0830 (12)0.0751 (10)0.0444 (7)0.0300 (9)0.0083 (7)0.0269 (7)
O3B0.1028 (14)0.0552 (8)0.0543 (8)0.0157 (8)0.0304 (8)0.0283 (7)
O4B0.0800 (11)0.0481 (8)0.0605 (9)0.0220 (7)0.0250 (8)0.0102 (7)
N1B0.0480 (8)0.0403 (7)0.0440 (8)0.0111 (6)0.0096 (6)0.0132 (6)
N2B0.0465 (8)0.0401 (7)0.0396 (7)0.0060 (6)0.0089 (6)0.0160 (6)
C1B0.0382 (8)0.0395 (8)0.0376 (8)0.0067 (6)0.0064 (6)0.0134 (6)
C2B0.0506 (10)0.0433 (9)0.0442 (9)0.0100 (7)0.0103 (7)0.0084 (7)
C3B0.0775 (15)0.0518 (11)0.0430 (10)0.0119 (10)0.0243 (9)0.0126 (8)
C4B0.0593 (11)0.0450 (9)0.0394 (9)0.0040 (8)0.0115 (8)0.0151 (7)
C5B0.0955 (19)0.0489 (11)0.0579 (13)0.0094 (11)0.0111 (12)0.0255 (10)
C6B0.104 (2)0.0477 (11)0.0687 (14)0.0285 (12)0.0197 (13)0.0182 (10)
C7B0.0803 (15)0.0423 (10)0.0653 (13)0.0231 (9)0.0347 (11)0.0206 (9)

Geometric parameters (Å, °)

S1A—O1A1.4334 (16)S1B—O1B1.4234 (16)
S1A—O2A1.4356 (14)S1B—O2B1.4260 (16)
S1A—C7A1.7429 (18)S1B—C7B1.751 (2)
S1A—C1A1.8059 (15)S1B—C1B1.8018 (17)
O3A—C4A1.338 (2)O3B—C4B1.333 (2)
O3A—C5A1.436 (3)O3B—C5B1.441 (3)
O4A—C2A1.342 (2)O4B—C2B1.342 (2)
O4A—C6A1.443 (2)O4B—C6B1.442 (3)
N1A—C1A1.322 (2)N1B—C1B1.320 (2)
N1A—C4A1.339 (2)N1B—C2B1.339 (2)
N2A—C1A1.321 (2)N2B—C1B1.317 (2)
N2A—C2A1.334 (2)N2B—C4B1.340 (2)
C2A—C3A1.386 (2)C2B—C3B1.375 (3)
C3A—C4A1.382 (2)C3B—C4B1.381 (3)
C3A—H3AA0.93C3B—H3BA0.93
C5A—H5AA0.96C5B—H5BA0.96
C5A—H5AB0.96C5B—H5BB0.96
C5A—H5AC0.96C5B—H5BC0.96
C6A—H6AA0.96C6B—H6BA0.96
C6A—H6AB0.96C6B—H6BB0.96
C6A—H6AC0.96C6B—H6BC0.96
C7A—H7AA0.96C7B—H7BA0.96
C7A—H7AB0.96C7B—H7BB0.96
C7A—H7AC0.96C7B—H7BC0.96
O1A—S1A—O2A117.87 (10)O1B—S1B—O2B117.30 (11)
O1A—S1A—C7A109.37 (10)O1B—S1B—C7B110.02 (12)
O2A—S1A—C7A109.13 (9)O2B—S1B—C7B109.13 (12)
O1A—S1A—C1A107.07 (8)O1B—S1B—C1B107.47 (9)
O2A—S1A—C1A108.07 (8)O2B—S1B—C1B107.25 (9)
C7A—S1A—C1A104.49 (8)C7B—S1B—C1B104.92 (9)
C4A—O3A—C5A118.66 (14)C4B—O3B—C5B118.20 (16)
C2A—O4A—C6A117.66 (14)C2B—O4B—C6B117.81 (17)
C1A—N1A—C4A113.74 (14)C1B—N1B—C2B113.47 (15)
C1A—N2A—C2A113.88 (14)C1B—N2B—C4B113.85 (15)
N2A—C1A—N1A130.25 (14)N2B—C1B—N1B130.63 (16)
N2A—C1A—S1A115.13 (11)N2B—C1B—S1B115.98 (12)
N1A—C1A—S1A114.55 (11)N1B—C1B—S1B113.38 (13)
N2A—C2A—O4A119.16 (15)N1B—C2B—O4B119.64 (18)
N2A—C2A—C3A123.00 (15)N1B—C2B—C3B122.83 (17)
O4A—C2A—C3A117.83 (15)O4B—C2B—C3B117.51 (17)
C4A—C3A—C2A116.11 (15)C2B—C3B—C4B116.88 (17)
C4A—C3A—H3AA121.9C2B—C3B—H3BA121.6
C2A—C3A—H3AA121.9C4B—C3B—H3BA121.6
O3A—C4A—N1A119.54 (15)O3B—C4B—N2B119.62 (17)
O3A—C4A—C3A117.47 (15)O3B—C4B—C3B118.09 (17)
N1A—C4A—C3A122.99 (15)N2B—C4B—C3B122.29 (17)
O3A—C5A—H5AA109.5O3B—C5B—H5BA109.5
O3A—C5A—H5AB109.5O3B—C5B—H5BB109.5
H5AA—C5A—H5AB109.5H5BA—C5B—H5BB109.5
O3A—C5A—H5AC109.5O3B—C5B—H5BC109.5
H5AA—C5A—H5AC109.5H5BA—C5B—H5BC109.5
H5AB—C5A—H5AC109.5H5BB—C5B—H5BC109.5
O4A—C6A—H6AA109.5O4B—C6B—H6BA109.5
O4A—C6A—H6AB109.5O4B—C6B—H6BB109.5
H6AA—C6A—H6AB109.5H6BA—C6B—H6BB109.5
O4A—C6A—H6AC109.5O4B—C6B—H6BC109.5
H6AA—C6A—H6AC109.5H6BA—C6B—H6BC109.5
H6AB—C6A—H6AC109.5H6BB—C6B—H6BC109.5
S1A—C7A—H7AA109.5S1B—C7B—H7BA109.5
S1A—C7A—H7AB109.5S1B—C7B—H7BB109.5
H7AA—C7A—H7AB109.5H7BA—C7B—H7BB109.5
S1A—C7A—H7AC109.5S1B—C7B—H7BC109.5
H7AA—C7A—H7AC109.5H7BA—C7B—H7BC109.5
H7AB—C7A—H7AC109.5H7BB—C7B—H7BC109.5
C2A—N2A—C1A—N1A−0.7 (3)C4B—N2B—C1B—N1B1.4 (3)
C2A—N2A—C1A—S1A−177.62 (12)C4B—N2B—C1B—S1B−179.50 (13)
C4A—N1A—C1A—N2A−0.6 (3)C2B—N1B—C1B—N2B−1.2 (3)
C4A—N1A—C1A—S1A176.33 (12)C2B—N1B—C1B—S1B179.75 (13)
O1A—S1A—C1A—N2A91.31 (14)O1B—S1B—C1B—N2B−110.99 (15)
O2A—S1A—C1A—N2A−140.77 (13)O2B—S1B—C1B—N2B122.06 (15)
C7A—S1A—C1A—N2A−24.64 (15)C7B—S1B—C1B—N2B6.09 (18)
O1A—S1A—C1A—N1A−86.07 (14)O1B—S1B—C1B—N1B68.23 (16)
O2A—S1A—C1A—N1A41.86 (14)O2B—S1B—C1B—N1B−58.72 (16)
C7A—S1A—C1A—N1A157.98 (13)C7B—S1B—C1B—N1B−174.69 (15)
C1A—N2A—C2A—O4A−179.19 (16)C1B—N1B—C2B—O4B−179.21 (18)
C1A—N2A—C2A—C3A1.8 (2)C1B—N1B—C2B—C3B−0.8 (3)
C6A—O4A—C2A—N2A3.3 (3)C6B—O4B—C2B—N1B−14.0 (3)
C6A—O4A—C2A—C3A−177.70 (18)C6B—O4B—C2B—C3B167.5 (2)
N2A—C2A—C3A—C4A−1.6 (3)N1B—C2B—C3B—C4B2.1 (3)
O4A—C2A—C3A—C4A179.42 (16)O4B—C2B—C3B—C4B−179.4 (2)
C5A—O3A—C4A—N1A−3.4 (3)C5B—O3B—C4B—N2B−2.2 (3)
C5A—O3A—C4A—C3A177.06 (19)C5B—O3B—C4B—C3B178.3 (2)
C1A—N1A—C4A—O3A−178.65 (15)C1B—N2B—C4B—O3B−179.31 (19)
C1A—N1A—C4A—C3A0.8 (2)C1B—N2B—C4B—C3B0.2 (3)
C2A—C3A—C4A—O3A179.63 (16)C2B—C3B—C4B—O3B177.7 (2)
C2A—C3A—C4A—N1A0.1 (3)C2B—C3B—C4B—N2B−1.8 (3)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C3A—H3AA···O2Ai0.932.423.336 (2)169
C5A—H5AC···O2Bii0.962.553.303 (3)135
C7A—H7AA···O4Aiii0.962.503.426 (2)161

Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+1, −z; (iii) x−1, y, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI5121).

References

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