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

Singh, D.P.; Pratap, S.; Gupta, S.K.; Butcher, R.J.

doi:10.1107/S1600536812044029

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

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

doi:10.1107/S1600536812044029

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

Durga P. Singh,^a Seema Pratap,^a Sushil K. Gupta ^b and Ray J. Butcher ^c ^*

^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 ). 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 (2001 ); Hassan et al. (2007 ); Pérez et al. (2008 ); Yan & Xue (2008 ).

Experimental

Crystal data

C₁₀H₈N₄O₂S
M_r = 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 ) T_min = 0.421, T_max = 1.000
6957 measured reflections
2028 independent reflections
1951 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.038
wR(F²) = 0.108
S = 1.04
2028 reflections
154 parameters
H-atom parameters constrained
Δρ_max = 0.46 e Å⁻³
Δρ_min = −0.21 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812044029/lh5548sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812044029/lh5548Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812044029/lh5548Isup3.cml

checkCIF report

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 C═S and the other is syn in the urea moiety. Furthermore, the amide C═S and the C═O 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.

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

	Fig. 1. The molecular structure of the title compound showing 30% probability displacement ellipsoids. Dashed lines indicate an intramolecular N—H···N hydrogen bond.
	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

C₁₀H₈N₄O₂S	F(000) = 512
M_r = 248.26	D_x = 1.572 Mg m⁻³
Monoclinic, P2₁/n	Cu Kα radiation, λ = 1.54178 Å
Hall symbol: -P 2yn	Cell parameters from 4415 reflections
a = 5.6962 (2) Å	θ = 4.2–72.7°
b = 21.0530 (7) Å	µ = 2.74 mm⁻¹
c = 8.7901 (3) Å	T = 123 K
β = 95.559 (3)°	Plate, colorless
V = 1049.17 (6) Å³	0.40 × 0.22 × 0.11 mm
Z = 4

Data collection top

Agilent Xcalibur (Ruby, Gemini) diffractometer	2028 independent reflections
Radiation source: Enhance (Cu) X-ray Source	1951 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
Detector resolution: 10.5081 pixels mm^-1	θ_max = 72.8°, θ_min = 4.2°
ω scans	h = −6→5
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −25→25
T_min = 0.421, T_max = 1.000	l = −10→9
6957 measured reflections

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)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.108	H-atom parameters constrained
S = 1.04	w = 1/[σ²(F_o²) + (0.0735P)² + 0.4136P] where P = (F_o² + 2F_c²)/3
2028 reflections	(Δ/σ)_max = 0.001
154 parameters	Δρ_max = 0.46 e Å⁻³
0 restraints	Δρ_min = −0.21 e Å⁻³

Crystal data top

C₁₀H₈N₄O₂S	V = 1049.17 (6) Å³
M_r = 248.26	Z = 4
Monoclinic, P2₁/n	Cu Kα radiation
a = 5.6962 (2) Å	µ = 2.74 mm⁻¹
b = 21.0530 (7) Å	T = 123 K
c = 8.7901 (3) Å	0.40 × 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)
T_min = 0.421, T_max = 1.000	R_int = 0.028
6957 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.038	0 restraints
wR(F²) = 0.108	H-atom parameters constrained
S = 1.04	Δρ_max = 0.46 e Å⁻³
2028 reflections	Δρ_min = −0.21 e Å⁻³
154 parameters

Special details top

Experimental. FT IR (selected, KBr, cm^-1):3424, 3207 [ν(N – H)]; 1712 [amide-I,C═O]; 1586, 1556 [ν(C═C)]; 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

	x	y	z	U_iso*/U_eq
S1	0.47026 (7)	0.555126 (18)	0.19269 (4)	0.02308 (17)
O1	−0.1466 (2)	0.71757 (6)	0.45239 (14)	0.0270 (3)
O2	0.0499 (2)	0.63600 (6)	0.26198 (14)	0.0283 (3)
N1	0.3619 (2)	0.61674 (6)	0.44577 (15)	0.0214 (3)
H1B	0.4047	0.6248	0.5403	0.026*
N2	0.7006 (2)	0.55592 (6)	0.46685 (16)	0.0201 (3)
H2B	0.7901	0.5300	0.4235	0.024*
N3	0.6446 (2)	0.60768 (6)	0.69888 (15)	0.0234 (3)
N4	0.9782 (2)	0.54126 (7)	0.67136 (15)	0.0216 (3)
C1	−0.1833 (3)	0.76232 (8)	0.5596 (2)	0.0285 (4)
H1A	−0.3194	0.7867	0.5597	0.034*
C2	0.0017 (3)	0.76645 (8)	0.6641 (2)	0.0304 (4)
H2A	0.0183	0.7937	0.7478	0.036*
C3	0.1690 (3)	0.72089 (8)	0.6224 (2)	0.0288 (4)
H3A	0.3162	0.7124	0.6737	0.035*
C4	0.0718 (3)	0.69251 (7)	0.49378 (18)	0.0214 (3)
C5	0.1539 (3)	0.64564 (7)	0.38553 (18)	0.0204 (3)
C6	0.5082 (3)	0.57705 (7)	0.37439 (17)	0.0192 (3)
C7	0.7750 (3)	0.56938 (7)	0.61922 (18)	0.0196 (3)
C8	0.7219 (3)	0.61687 (8)	0.84626 (19)	0.0257 (4)
H8A	0.6344	0.6426	0.9055	0.031*
C9	0.9258 (3)	0.58957 (8)	0.91292 (19)	0.0261 (4)
H9A	0.9775	0.5958	1.0154	0.031*
C10	1.0498 (3)	0.55213 (8)	0.81814 (19)	0.0250 (4)
H10A	1.1902	0.5336	0.8591	0.030*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0259 (3)	0.0236 (3)	0.0195 (3)	0.00267 (13)	0.00100 (17)	−0.00364 (13)
O1	0.0233 (6)	0.0286 (6)	0.0280 (6)	0.0067 (5)	−0.0032 (5)	−0.0046 (5)
O2	0.0252 (6)	0.0347 (7)	0.0245 (6)	0.0026 (5)	−0.0006 (5)	−0.0060 (5)
N1	0.0242 (7)	0.0215 (6)	0.0182 (6)	0.0022 (5)	0.0012 (5)	−0.0023 (5)
N2	0.0232 (7)	0.0180 (6)	0.0195 (7)	0.0021 (5)	0.0041 (5)	−0.0022 (5)
N3	0.0273 (7)	0.0210 (6)	0.0218 (7)	0.0036 (5)	0.0024 (5)	−0.0017 (5)
N4	0.0224 (7)	0.0207 (6)	0.0217 (7)	0.0005 (5)	0.0026 (5)	−0.0017 (5)
C1	0.0292 (9)	0.0246 (8)	0.0315 (9)	0.0081 (6)	0.0023 (7)	−0.0038 (6)
C2	0.0315 (9)	0.0282 (9)	0.0304 (9)	0.0086 (7)	−0.0025 (7)	−0.0094 (7)
C3	0.0264 (8)	0.0286 (8)	0.0303 (9)	0.0072 (7)	−0.0030 (7)	−0.0073 (7)
C4	0.0198 (7)	0.0201 (7)	0.0240 (8)	0.0013 (6)	0.0010 (6)	0.0024 (6)
C5	0.0212 (7)	0.0194 (7)	0.0206 (7)	−0.0026 (6)	0.0023 (6)	0.0006 (6)
C6	0.0219 (7)	0.0152 (7)	0.0210 (7)	−0.0023 (5)	0.0042 (6)	0.0003 (5)
C7	0.0224 (8)	0.0163 (7)	0.0205 (8)	−0.0012 (6)	0.0037 (6)	0.0014 (6)
C8	0.0316 (9)	0.0240 (8)	0.0218 (8)	0.0038 (6)	0.0041 (6)	−0.0034 (6)
C9	0.0323 (9)	0.0253 (8)	0.0202 (8)	0.0011 (6)	0.0000 (6)	−0.0034 (6)
C10	0.0241 (8)	0.0258 (9)	0.0245 (9)	0.0022 (6)	−0.0011 (7)	0.0002 (6)

Geometric parameters (Å, º) top

S1—C6	1.6565 (15)	N4—C7	1.340 (2)
O1—C1	1.363 (2)	C1—C2	1.332 (3)
O1—C4	1.3679 (19)	C1—H1A	0.9300
O2—C5	1.203 (2)	C2—C3	1.425 (2)
N1—C6	1.3739 (19)	C2—H2A	0.9300
N1—C5	1.390 (2)	C3—C4	1.349 (2)
N1—H1B	0.8600	C3—H3A	0.9300
N2—C6	1.373 (2)	C4—C5	1.478 (2)
N2—C7	1.394 (2)	C8—C9	1.375 (2)
N2—H2B	0.8600	C8—H8A	0.9300
N3—C7	1.339 (2)	C9—C10	1.389 (2)
N3—C8	1.341 (2)	C9—H9A	0.9300
N4—C10	1.335 (2)	C10—H10A	0.9300

C1—O1—C4	106.22 (13)	O1—C4—C5	115.00 (14)
C6—N1—C5	128.64 (13)	O2—C5—N1	126.67 (15)
C6—N1—H1B	115.7	O2—C5—C4	122.34 (15)
C5—N1—H1B	115.7	N1—C5—C4	110.98 (13)
C6—N2—C7	130.81 (13)	N2—C6—N1	114.28 (13)
C6—N2—H2B	114.6	N2—C6—S1	120.16 (11)
C7—N2—H2B	114.6	N1—C6—S1	125.56 (12)
C7—N3—C8	116.43 (14)	N3—C7—N4	126.26 (14)
C10—N4—C7	115.33 (14)	N3—C7—N2	119.48 (14)
C2—C1—O1	110.97 (15)	N4—C7—N2	114.26 (13)
C2—C1—H1A	124.5	N3—C8—C9	122.41 (15)
O1—C1—H1A	124.5	N3—C8—H8A	118.8
C1—C2—C3	106.41 (15)	C9—C8—H8A	118.8
C1—C2—H2A	126.8	C8—C9—C10	116.07 (15)
C3—C2—H2A	126.8	C8—C9—H9A	122.0
C4—C3—C2	106.46 (15)	C10—C9—H9A	122.0
C4—C3—H3A	126.8	N4—C10—C9	123.46 (15)
C2—C3—H3A	126.8	N4—C10—H10A	118.3
C3—C4—O1	109.94 (14)	C9—C10—H10A	118.3
C3—C4—C5	134.87 (15)

C4—O1—C1—C2	0.5 (2)	C7—N2—C6—S1	177.23 (12)
O1—C1—C2—C3	−0.5 (2)	C5—N1—C6—N2	−179.49 (14)
C1—C2—C3—C4	0.3 (2)	C5—N1—C6—S1	1.3 (2)
C2—C3—C4—O1	0.0 (2)	C8—N3—C7—N4	−2.3 (2)
C2—C3—C4—C5	174.44 (18)	C8—N3—C7—N2	177.72 (14)
C1—O1—C4—C3	−0.26 (18)	C10—N4—C7—N3	1.7 (2)
C1—O1—C4—C5	−175.93 (14)	C10—N4—C7—N2	−178.32 (13)
C6—N1—C5—O2	8.1 (3)	C6—N2—C7—N3	2.0 (2)
C6—N1—C5—C4	−171.00 (14)	C6—N2—C7—N4	−177.98 (14)
C3—C4—C5—O2	−165.63 (19)	C7—N3—C8—C9	1.0 (2)
O1—C4—C5—O2	8.6 (2)	N3—C8—C9—C10	0.6 (2)
C3—C4—C5—N1	13.5 (3)	C7—N4—C10—C9	0.2 (2)
O1—C4—C5—N1	−172.23 (12)	C8—C9—C10—N4	−1.3 (2)
C7—N2—C6—N1	−2.0 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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.

Experimental details

Crystal data
Chemical formula	C₁₀H₈N₄O₂S
M_r	248.26
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	123
a, b, c (Å)	5.6962 (2), 21.0530 (7), 8.7901 (3)
β (°)	95.559 (3)
V (Å³)	1049.17 (6)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	2.74
Crystal size (mm)	0.40 × 0.22 × 0.11

Data collection
Diffractometer	Agilent Xcalibur (Ruby, Gemini) diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2011)
T_min, T_max	0.421, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	6957, 2028, 1951
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.620

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.038, 0.108, 1.04
No. of reflections	2028
No. of parameters	154
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	D—H···A
N1—H1B···N3	0.86	1.89	2.6240 (18)	142.4
N2—H2B···N4ⁱ	0.86	2.21	3.0726 (19)	175.4
C10—H10A···S1ⁱ	0.93	2.76	3.5536 (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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