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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 68| Part 12| December 2012| Pages o3300-o3301

3-[(Furan-2-yl)carbon­yl]-1-(pyrimi­din-2-yl)thio­urea

aDepartment of Chemistry, M.M.V., Banaras Hindu University, Varanasi 221 005, India, bSchool of Studies in Chemistry, Jiwaji University, Gwalior 474 011, India, and cDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA
*Correspondence e-mail: rbutcher99@yahoo.com

(Received 17 October 2012; accepted 23 October 2012; online 7 November 2012)

The title compound, C10H8N4O2S, was synthesized from furoyl isothio­cynate and 2-amino­pyrimidine in dry acetone. The two N—H groups are in an anti conformation with respect to each other and one N—H group is anti to the C=S group while the other is syn. The amide C=S and the C=O groups are syn to each other. The mean plane of the central thio­urea fragment forms dihedral angles of 13.50 (14) and 5.03 (11)° with the furan and pyrimidine rings, respectively. The dihedral angle between the furan and pyrimidine rings is 18.43 (10)°. The mol­ecular conformation is stabilized by an intra­molecular N—H⋯N hydrogen bond generating an S(6) ring motif. In the crystal, mol­ecules are linked by pairs of N—H⋯N and weak C—H⋯S hydrogen bonds to form inversion dimers.

Related literature

For a general background to the biological activity of thio­urea, see: Koketsu & Ishihara (2006[Koketsu, M. & Ishihara, H. (2006). Curr. Org. Synth. 3, 439-455.]). For heterocyclic derivatives, metal complexes and mol­ecular electronics, see: Zeng et al. (2003[Zeng, R.-S., Zou, S.-J. & Shen, Q. (2003). Org. Lett. 5, 1657-1659.]); D'hooghe et al. (2005[D'hooghe, M., Waterinckx, A. & De Kimpe, N. (2005). J. Org. Chem. 70, 227-232.]); Aly et al. (2007[Aly, A. A., Ahmed, E. K., El-Mokadem, K. M. & Hegazy, M. E. F. (2007). J. Sulfur Chem. 28, 73-93.]); Duque et al. (2009[Duque, J., Estevez-Hernandez, O., Reguera, E., Ellena, J. & Correa, R. S. (2009). J. Coord. Chem. 62, 2804-2813.]). For related structures, see: Singh et al. (2012[Singh, D. P., Pratap, S., Gupta, S. K. & Butcher, R. J. (2012). Acta Cryst. E68, o2882-o2883.]); Koch (2001[Koch, K. R. (2001). Coord. Chem. Rev. 216-217, 473-488.]); Hassan et al. (2007[Hassan, N. N. N., Kadir, M. A., Yusof, M. S. M. & Yamin, B. M. (2007). Acta Cryst. E63, o4224.]); Pérez et al. (2008[Pérez, H., Mascarenhas, Y., Estévez-Hernández, O., Santos Jr, S. & Duque, J. (2008). Acta Cryst. E64, o513.]); Yan & Xue (2008[Yan, L. & Xue, S.-J. (2008). Chin. J. Struct. Chem. 27, 543-546.]).

[Scheme 1]

Experimental

Crystal data
  • C10H8N4O2S

  • Mr = 248.26

  • Monoclinic, P 21 /n

  • a = 5.6962 (2) Å

  • b = 21.0530 (7) Å

  • c = 8.7901 (3) Å

  • β = 95.559 (3)°

  • V = 1049.17 (6) Å3

  • Z = 4

  • Cu Kα radiation

  • μ = 2.74 mm−1

  • T = 123 K

  • 0.40 × 0.22 × 0.11 mm

Data collection
  • Agilent Xcalibur (Ruby, Gemini) diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.421, Tmax = 1.000

  • 6957 measured reflections

  • 2028 independent reflections

  • 1951 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.108

  • S = 1.04

  • 2028 reflections

  • 154 parameters

  • H-atom parameters constrained

  • Δρmax = 0.46 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1B⋯N3 0.86 1.89 2.6240 (18) 142
N2—H2B⋯N4i 0.86 2.21 3.0726 (19) 175
C10—H10A⋯S1i 0.93 2.76 3.5536 (17) 144
Symmetry code: (i) -x+2, -y+1, -z+1.

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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

Thiourea and its derivatives are known to exhibit a wide variety of biological activities (Koketsu & Ishihara, 2006). These are also widely used as precursors or intermediates towards the syntheisis of a variety of heterocyclic compounds (Zeng et al., 2003; D'hooghe, et al., 2005). In addition, aroylthioureas have applications in metal complexes and molecular electronics (Aly et al., 2007; Duque et al., 2009). The structure of a related compound was recently published (Yan & Xue, 2008) in which the molecule showed excellent herbicidal activity.

In view of the biological importance of thiourea and its furoic acid derviatives, the structure of the title compound was determined. In the title compound (Fig. 1), the conformation of the two N—H bonds are anti to each other, and one of them is anti to the CS and the other is syn in the urea moiety. Furthermore, the amide CS and the CO groups are syn to each other, similar to the syn conformation observed in 1-furoyl-3-methyl-3-phenylthiourea (Pérez et al., 2008) and in N-(2-furoyl)-N'(6-methyl-2-pyridyl)thiourea (Hassan et al., 2007). The bond lengths and angles in the title compound are comparable to other thiourea derivatives (Koch 2001; Pérez et al., 2008; Singh et al., 2012). The C6—S1 and C5—O2 bonds show typical double-bond character. However, the C—N bond lengths, C5—N1, C6—N1, C6—N2 are shorter than the normal C—N single-bond length of about 1.48 Å. These results can be explained by the existence of resonance in this part of the molecule. The central thiourea fragment (O2/C5/N1/C6/N2) makes dihedral angle of 13.50 (14)° with furan ring (O1/C1/C2/C3/C4)and 5.03 (11)° with pyrimidine ring (C7/N3/C8/C9/C10/N4), respectively. The dihedral angle between the mean planes of the furan and pyrimidine rings is 18.43 (10)°. The moleculer geometry is stabilized by an intramolecular N—H···N hydrogen bond generating an S(6) ring motif. In the crystal, molecules are linked by pairs of N—H···N and weak C—H···S hydrogen bonds (Table 1) forming centrosymmetric dimers (Fig. 2).

Related literature top

For a general background to the biological activity of thiourea, see: Koketsu & Ishihara (2006). For heterocyclic derivatives, metal complexes and molecular electronics, see: Zeng et al. (2003); D'hooghe et al. (2005); Aly et al. (2007); Duque et al. (2009). For related structures, see: Singh et al. (2012); Koch et al. (2001); Hassan et al. (2007); Pérez et al. (2008); Yan & Xue (2008).

Experimental top

A solution of 2-thiophenecarbonyl chloride (0.01 mol) in anhydrous acetone (80 ml) was added dropwise to a suspension of ammonium thiocyanate (0.01 mol) in anhydrous acetone (50 ml) and the reaction mixture was refluxed for 50 minutes. After cooling to room temperature, a solution of 4-chloroaniline (0.01 mol) in dry acetone (25 ml) was added and the resulting mixture refluxed for 2 h. The reaction mixture was poured into five times its volume of cold water, upon which the thiourea precipitated. The resulting solide product was crystallized from acetone yielding yellow colour X-ray quality single crystals. Yield: 80%; M.P.: 455 - 456 K). Anal. Calc. for C10H8N4O2S (%): C, 48.38; H,3.25; N, 22.57. Found: C, 48.49; H, 3.28; N, 22.50.

Refinement top

All H atoms were placed in calculated positions and refined using a riding-model approximation with C—H = 0.93 Å, N—H = 0.86Å and Uiso(H) = 1.2Ueq(C,N).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); 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 the title compound showing 30% probability displacement ellipsoids. Dashed lines indicate an intramolecular N—H···N hydrogen bond.
[Figure 2] Fig. 2. Crystal packing for the title compound viewed along the c axis. Dashed lines indicate intermolecular N—H···N and C—H···S hydrogen bonds.
3-[(Furan-2-yl)carbonyl]-1-(pyrimidin-2-yl)thiourea top
Crystal data top
C10H8N4O2SF(000) = 512
Mr = 248.26Dx = 1.572 Mg m3
Monoclinic, P21/nCu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2ynCell parameters from 4415 reflections
a = 5.6962 (2) Åθ = 4.2–72.7°
b = 21.0530 (7) ŵ = 2.74 mm1
c = 8.7901 (3) ÅT = 123 K
β = 95.559 (3)°Plate, colorless
V = 1049.17 (6) Å30.40 × 0.22 × 0.11 mm
Z = 4
Data collection top
Agilent Xcalibur (Ruby, Gemini)
diffractometer
2028 independent reflections
Radiation source: Enhance (Cu) X-ray Source1951 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
Detector resolution: 10.5081 pixels mm-1θmax = 72.8°, θmin = 4.2°
ω scansh = 65
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
k = 2525
Tmin = 0.421, Tmax = 1.000l = 109
6957 measured 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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.108H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0735P)2 + 0.4136P]
where P = (Fo2 + 2Fc2)/3
2028 reflections(Δ/σ)max = 0.001
154 parametersΔρmax = 0.46 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C10H8N4O2SV = 1049.17 (6) Å3
Mr = 248.26Z = 4
Monoclinic, P21/nCu Kα radiation
a = 5.6962 (2) ŵ = 2.74 mm1
b = 21.0530 (7) ÅT = 123 K
c = 8.7901 (3) Å0.40 × 0.22 × 0.11 mm
β = 95.559 (3)°
Data collection top
Agilent Xcalibur (Ruby, Gemini)
diffractometer
2028 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
1951 reflections with I > 2σ(I)
Tmin = 0.421, Tmax = 1.000Rint = 0.028
6957 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0380 restraints
wR(F2) = 0.108H-atom parameters constrained
S = 1.04Δρmax = 0.46 e Å3
2028 reflectionsΔρmin = 0.21 e Å3
154 parameters
Special details top

Experimental. FT IR (selected, KBr, cm-1):3424, 3207 [ν(N – H)]; 1712 [amide-I,CO]; 1586, 1556 [ν(CC)]; 1505[thioureido-I], 1327 [thioureido-II], 1177 [thioureido-III], 763 [thioureido-IV]. 1H NMR (300 MHz, dmso-d6): δ 14.08 (s, 1H, H-bonded N–H); 11.90 (s, 1H,free N–H); 8.80 (d,J = 7.1 Hz, 2H, pyrimidine CH); 8.05 (d, J = 7.5 Hz, 1H, furan CH); 7.50(d,J = 7.8 Hz, 1H, pyrimidine CH);7.30 (t, J1(H,H) = 6.8 Hz,J2(H,H) = 7.1 Hz, 1H, pyrimidine CH);6.76 (t, J(H,H) = 7.8 Hz, 1H, furan CH). 13C NMR (75 MHz,dmso-d6): δ 177.4, 158.5, 157.1, 155.4, 147.6, 146.4, 117.6, 117.1, 112.9.

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
S10.47026 (7)0.555126 (18)0.19269 (4)0.02308 (17)
O10.1466 (2)0.71757 (6)0.45239 (14)0.0270 (3)
O20.0499 (2)0.63600 (6)0.26198 (14)0.0283 (3)
N10.3619 (2)0.61674 (6)0.44577 (15)0.0214 (3)
H1B0.40470.62480.54030.026*
N20.7006 (2)0.55592 (6)0.46685 (16)0.0201 (3)
H2B0.79010.53000.42350.024*
N30.6446 (2)0.60768 (6)0.69888 (15)0.0234 (3)
N40.9782 (2)0.54126 (7)0.67136 (15)0.0216 (3)
C10.1833 (3)0.76232 (8)0.5596 (2)0.0285 (4)
H1A0.31940.78670.55970.034*
C20.0017 (3)0.76645 (8)0.6641 (2)0.0304 (4)
H2A0.01830.79370.74780.036*
C30.1690 (3)0.72089 (8)0.6224 (2)0.0288 (4)
H3A0.31620.71240.67370.035*
C40.0718 (3)0.69251 (7)0.49378 (18)0.0214 (3)
C50.1539 (3)0.64564 (7)0.38553 (18)0.0204 (3)
C60.5082 (3)0.57705 (7)0.37439 (17)0.0192 (3)
C70.7750 (3)0.56938 (7)0.61922 (18)0.0196 (3)
C80.7219 (3)0.61687 (8)0.84626 (19)0.0257 (4)
H8A0.63440.64260.90550.031*
C90.9258 (3)0.58957 (8)0.91292 (19)0.0261 (4)
H9A0.97750.59581.01540.031*
C101.0498 (3)0.55213 (8)0.81814 (19)0.0250 (4)
H10A1.19020.53360.85910.030*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0259 (3)0.0236 (3)0.0195 (3)0.00267 (13)0.00100 (17)0.00364 (13)
O10.0233 (6)0.0286 (6)0.0280 (6)0.0067 (5)0.0032 (5)0.0046 (5)
O20.0252 (6)0.0347 (7)0.0245 (6)0.0026 (5)0.0006 (5)0.0060 (5)
N10.0242 (7)0.0215 (6)0.0182 (6)0.0022 (5)0.0012 (5)0.0023 (5)
N20.0232 (7)0.0180 (6)0.0195 (7)0.0021 (5)0.0041 (5)0.0022 (5)
N30.0273 (7)0.0210 (6)0.0218 (7)0.0036 (5)0.0024 (5)0.0017 (5)
N40.0224 (7)0.0207 (6)0.0217 (7)0.0005 (5)0.0026 (5)0.0017 (5)
C10.0292 (9)0.0246 (8)0.0315 (9)0.0081 (6)0.0023 (7)0.0038 (6)
C20.0315 (9)0.0282 (9)0.0304 (9)0.0086 (7)0.0025 (7)0.0094 (7)
C30.0264 (8)0.0286 (8)0.0303 (9)0.0072 (7)0.0030 (7)0.0073 (7)
C40.0198 (7)0.0201 (7)0.0240 (8)0.0013 (6)0.0010 (6)0.0024 (6)
C50.0212 (7)0.0194 (7)0.0206 (7)0.0026 (6)0.0023 (6)0.0006 (6)
C60.0219 (7)0.0152 (7)0.0210 (7)0.0023 (5)0.0042 (6)0.0003 (5)
C70.0224 (8)0.0163 (7)0.0205 (8)0.0012 (6)0.0037 (6)0.0014 (6)
C80.0316 (9)0.0240 (8)0.0218 (8)0.0038 (6)0.0041 (6)0.0034 (6)
C90.0323 (9)0.0253 (8)0.0202 (8)0.0011 (6)0.0000 (6)0.0034 (6)
C100.0241 (8)0.0258 (9)0.0245 (9)0.0022 (6)0.0011 (7)0.0002 (6)
Geometric parameters (Å, º) top
S1—C61.6565 (15)N4—C71.340 (2)
O1—C11.363 (2)C1—C21.332 (3)
O1—C41.3679 (19)C1—H1A0.9300
O2—C51.203 (2)C2—C31.425 (2)
N1—C61.3739 (19)C2—H2A0.9300
N1—C51.390 (2)C3—C41.349 (2)
N1—H1B0.8600C3—H3A0.9300
N2—C61.373 (2)C4—C51.478 (2)
N2—C71.394 (2)C8—C91.375 (2)
N2—H2B0.8600C8—H8A0.9300
N3—C71.339 (2)C9—C101.389 (2)
N3—C81.341 (2)C9—H9A0.9300
N4—C101.335 (2)C10—H10A0.9300
C1—O1—C4106.22 (13)O1—C4—C5115.00 (14)
C6—N1—C5128.64 (13)O2—C5—N1126.67 (15)
C6—N1—H1B115.7O2—C5—C4122.34 (15)
C5—N1—H1B115.7N1—C5—C4110.98 (13)
C6—N2—C7130.81 (13)N2—C6—N1114.28 (13)
C6—N2—H2B114.6N2—C6—S1120.16 (11)
C7—N2—H2B114.6N1—C6—S1125.56 (12)
C7—N3—C8116.43 (14)N3—C7—N4126.26 (14)
C10—N4—C7115.33 (14)N3—C7—N2119.48 (14)
C2—C1—O1110.97 (15)N4—C7—N2114.26 (13)
C2—C1—H1A124.5N3—C8—C9122.41 (15)
O1—C1—H1A124.5N3—C8—H8A118.8
C1—C2—C3106.41 (15)C9—C8—H8A118.8
C1—C2—H2A126.8C8—C9—C10116.07 (15)
C3—C2—H2A126.8C8—C9—H9A122.0
C4—C3—C2106.46 (15)C10—C9—H9A122.0
C4—C3—H3A126.8N4—C10—C9123.46 (15)
C2—C3—H3A126.8N4—C10—H10A118.3
C3—C4—O1109.94 (14)C9—C10—H10A118.3
C3—C4—C5134.87 (15)
C4—O1—C1—C20.5 (2)C7—N2—C6—S1177.23 (12)
O1—C1—C2—C30.5 (2)C5—N1—C6—N2179.49 (14)
C1—C2—C3—C40.3 (2)C5—N1—C6—S11.3 (2)
C2—C3—C4—O10.0 (2)C8—N3—C7—N42.3 (2)
C2—C3—C4—C5174.44 (18)C8—N3—C7—N2177.72 (14)
C1—O1—C4—C30.26 (18)C10—N4—C7—N31.7 (2)
C1—O1—C4—C5175.93 (14)C10—N4—C7—N2178.32 (13)
C6—N1—C5—O28.1 (3)C6—N2—C7—N32.0 (2)
C6—N1—C5—C4171.00 (14)C6—N2—C7—N4177.98 (14)
C3—C4—C5—O2165.63 (19)C7—N3—C8—C91.0 (2)
O1—C4—C5—O28.6 (2)N3—C8—C9—C100.6 (2)
C3—C4—C5—N113.5 (3)C7—N4—C10—C90.2 (2)
O1—C4—C5—N1172.23 (12)C8—C9—C10—N41.3 (2)
C7—N2—C6—N12.0 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···N30.861.892.6240 (18)142
N2—H2B···N4i0.862.213.0726 (19)175
C10—H10A···S1i0.932.763.5536 (17)144
Symmetry code: (i) x+2, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC10H8N4O2S
Mr248.26
Crystal system, space groupMonoclinic, P21/n
Temperature (K)123
a, b, c (Å)5.6962 (2), 21.0530 (7), 8.7901 (3)
β (°) 95.559 (3)
V3)1049.17 (6)
Z4
Radiation typeCu Kα
µ (mm1)2.74
Crystal size (mm)0.40 × 0.22 × 0.11
Data collection
DiffractometerAgilent Xcalibur (Ruby, Gemini)
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2011)
Tmin, Tmax0.421, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
6957, 2028, 1951
Rint0.028
(sin θ/λ)max1)0.620
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.108, 1.04
No. of reflections2028
No. of parameters154
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.46, 0.21

Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···N30.861.892.6240 (18)142.4
N2—H2B···N4i0.862.213.0726 (19)175.4
C10—H10A···S1i0.932.763.5536 (17)143.8
Symmetry code: (i) x+2, y+1, z+1.
 

Acknowledgements

DPS and SP are grateful to Banaras Hindu University, Varanasi, for financial support. RJB acknowledges the NSF–MRI program (grant No. CHE0619278) for funds to purchase the X-ray diffractometer. SKG wishes to acknowledge the USIEF for the award of a Fulbright–Nehru Senior Research Fellowship.

References

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Volume 68| Part 12| December 2012| Pages o3300-o3301
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