organic compounds
1-(4-Chlorophenyl)-4,4,6-trimethyl-3,4-dihydropyrimidine-2(1H)-thione
aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt/Main, Germany
*Correspondence e-mail: aamersaeed@yahoo.com
The dihydropyrimidine ring of the title compound, C13H15ClN2S, adopts an with five almost coplanar atoms (r.m.s. deviation = 0.054 Å) and the C atom bearing the two methyl substituents deviating from this plane by 0.441 (2) Å. The best plane through the five almost coplanar atoms forms a dihedral angle of 89.56 (5)° with the benzene ring. The crystal packing is characterized by centrosymmetric dimers connected by pairs of N—H⋯S hydrogen bonds.
Related literature
For details of the biological activity of pyrimidine-2-thiones, see: Alam et al. (2005); Sriram et al. (2006); Leite et al. (2006); Kappe (2000); Rovnyak et al. (1995); Swamy et al. (2005). For a related structure, see: Yamin et al. (2005).
Experimental
Crystal data
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Refinement
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Data collection: X-AREA (Stoe & Cie, 2001); cell X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536810001777/zq2028sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810001777/zq2028Isup2.hkl
Potassium thiocyanate (5.4 mmol) was added to a stirred mixture of 4-methylpent-3-en-2-one (5.4 mmol), 4-chloroaniline (5.4 mmol) in dry acetone. The reaction mixture was refluxed for 3 hours. On completion of the reaction, the reaction mixture was cooled to room temperature and poured into ice-water. The precipitated compound was recrystallized from methanol to afford the title dihydropyrimidine-2-thione (62%). Recrystallization from methanol afforded the title compound as colourless crystals: Anal. calcd. for C13H15N2S: C, 58.53; H, 5.67; N, 10.50; S, 12.02%; found: C, 58.49; H, 5.72; N, 10.61; S, 12.14%;%.
Hydrogen atoms were located in a difference Fourier map but they were all included in calculated positions [Caromatic—H = 0.95 Å; Cmethyl—H = 0.98°] and refined as riding [Uiso(H) = 1.2Ueq(C) or Uiso(H) = 1.5Ueq(Cmethyl)]. The methyl groups were allowed to rotate but not to tip.
The title compound belongs to a novel and rare class of dihydropyrimidine-2-thiones. Their synthesis has been attracting widespread attention due to diverse pharmacological activities such as antibacterial (Alam et al., 2005), antitumour (Swamy et al., 2005), antioxidative (Sriram et al., 2006), analgesic and anti-inflammatory properties (Leite et al., 2006; Kappe, 2000). In addition, these compounds act as antihypertensive agents as well as calcium channel blockers and neuropeptide Y antagonists (Rovnyak et al., 1995). The formation of the closely related 4,4,6-trimethyl-1-phenyl-3,4-dihydropyrimidine-2(1H)-thione as a side product during the reaction of cinnamoyl isothiocyanate and aniline to afford the corresponding thiourea derivative has been reported (Yamin et al., 2005) The title compound was prepared by the reaction of 4-chloroaniline with 4-methylpent-3-en-2-one in presence of potassium thiocyanate in acetone.
The dihydropyrimidine ring of the title compound adopts an
with five almost coplanar atoms (r.m.s. deviation 0.054 Å) and the carbon atom bearing the two methyl substituents deviating from this plane by 0.441 (2) Å. The best plane through the six ring atoms forms a dihedral angle of 89.42 (5)° with the phenyl ring. The crystal packing is characterized by centrosymmetric dimers connected by N—H···S hydrogen bonds.For details of the biological activity of pyrimidine-2-thiones, see: Alam et al. (2005); Sriram et al. (2006); Leite et al. (2006); Kappe (2000); Rovnyak et al. (1995); Swamy et al. (2005). For related structures see: Yamin et al. (2005).
Data collection: X-AREA (Stoe & Cie, 2001); cell
X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. |
C13H15ClN2S | F(000) = 1120 |
Mr = 266.78 | Dx = 1.317 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 6686 reflections |
a = 20.6710 (18) Å | θ = 3.4–26.1° |
b = 10.8343 (10) Å | µ = 0.42 mm−1 |
c = 14.8619 (13) Å | T = 173 K |
β = 126.026 (5)° | Block, colourless |
V = 2691.9 (4) Å3 | 0.37 × 0.29 × 0.26 mm |
Z = 8 |
Stoe IPDS II two-circle diffractometer | 2512 independent reflections |
Radiation source: fine-focus sealed tube | 2134 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.049 |
ω scans | θmax = 25.7°, θmin = 3.4° |
Absorption correction: multi-scan (MULABS; Spek, 2009; Blessing, 1995) | h = −25→24 |
Tmin = 0.861, Tmax = 0.899 | k = −13→13 |
7624 measured reflections | l = −16→18 |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.093 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | w = 1/[σ2(Fo2) + (0.0634P)2] where P = (Fo2 + 2Fc2)/3 |
2512 reflections | (Δ/σ)max = 0.001 |
161 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.39 e Å−3 |
C13H15ClN2S | V = 2691.9 (4) Å3 |
Mr = 266.78 | Z = 8 |
Monoclinic, C2/c | Mo Kα radiation |
a = 20.6710 (18) Å | µ = 0.42 mm−1 |
b = 10.8343 (10) Å | T = 173 K |
c = 14.8619 (13) Å | 0.37 × 0.29 × 0.26 mm |
β = 126.026 (5)° |
Stoe IPDS II two-circle diffractometer | 2512 independent reflections |
Absorption correction: multi-scan (MULABS; Spek, 2009; Blessing, 1995) | 2134 reflections with I > 2σ(I) |
Tmin = 0.861, Tmax = 0.899 | Rint = 0.049 |
7624 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.093 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.02 | Δρmax = 0.22 e Å−3 |
2512 reflections | Δρmin = −0.39 e Å−3 |
161 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.57142 (2) | 0.69991 (4) | 0.42770 (3) | 0.02504 (14) | |
Cl1 | 0.68751 (3) | 0.59306 (4) | 0.93548 (3) | 0.03636 (15) | |
N1 | 0.47205 (7) | 0.78438 (12) | 0.47357 (11) | 0.0219 (3) | |
H1 | 0.4318 (11) | 0.7666 (19) | 0.2421 (18) | 0.027 (5)* | |
C2 | 0.48383 (9) | 0.75825 (14) | 0.39373 (13) | 0.0202 (3) | |
N3 | 0.42364 (8) | 0.78513 (13) | 0.28874 (12) | 0.0239 (3) | |
C4 | 0.33943 (9) | 0.80299 (15) | 0.24811 (13) | 0.0240 (4) | |
C5 | 0.34219 (9) | 0.86623 (15) | 0.34036 (14) | 0.0251 (3) | |
H5 | 0.2983 | 0.9165 | 0.3221 | 0.030* | |
C6 | 0.40392 (9) | 0.85420 (15) | 0.44661 (14) | 0.0238 (3) | |
C7 | 0.29744 (11) | 0.67811 (18) | 0.21978 (17) | 0.0364 (4) | |
H7A | 0.3015 | 0.6356 | 0.1651 | 0.055* | |
H7B | 0.2410 | 0.6907 | 0.1886 | 0.055* | |
H7C | 0.3229 | 0.6280 | 0.2874 | 0.055* | |
C8 | 0.29878 (10) | 0.88397 (18) | 0.14363 (15) | 0.0348 (4) | |
H9A | 0.3273 | 0.9627 | 0.1621 | 0.052* | |
H9B | 0.2432 | 0.8993 | 0.1157 | 0.052* | |
H9C | 0.2999 | 0.8416 | 0.0863 | 0.052* | |
C9 | 0.40992 (11) | 0.91451 (18) | 0.54228 (15) | 0.0342 (4) | |
H8A | 0.3607 | 0.9608 | 0.5143 | 0.051* | |
H8B | 0.4557 | 0.9710 | 0.5804 | 0.051* | |
H8C | 0.4173 | 0.8511 | 0.5946 | 0.051* | |
C11 | 0.52708 (9) | 0.73685 (15) | 0.58519 (12) | 0.0209 (3) | |
C12 | 0.51342 (9) | 0.62101 (15) | 0.60981 (13) | 0.0236 (3) | |
H12 | 0.4698 | 0.5727 | 0.5531 | 0.028* | |
C13 | 0.56377 (9) | 0.57500 (15) | 0.71809 (14) | 0.0251 (3) | |
H13 | 0.5550 | 0.4955 | 0.7359 | 0.030* | |
C14 | 0.62664 (9) | 0.64743 (15) | 0.79878 (13) | 0.0237 (3) | |
C15 | 0.64175 (9) | 0.76243 (16) | 0.77479 (14) | 0.0271 (4) | |
H15 | 0.6859 | 0.8099 | 0.8313 | 0.033* | |
C16 | 0.59136 (10) | 0.80791 (15) | 0.66666 (14) | 0.0260 (4) | |
H16 | 0.6009 | 0.8869 | 0.6488 | 0.031* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0186 (2) | 0.0362 (3) | 0.0192 (2) | 0.00399 (14) | 0.01047 (17) | 0.00264 (15) |
Cl1 | 0.0372 (2) | 0.0389 (3) | 0.0182 (2) | 0.00307 (17) | 0.00804 (19) | 0.00696 (16) |
N1 | 0.0217 (6) | 0.0262 (7) | 0.0175 (7) | 0.0037 (5) | 0.0114 (6) | 0.0023 (5) |
C2 | 0.0220 (7) | 0.0197 (7) | 0.0190 (7) | −0.0011 (6) | 0.0120 (6) | 0.0013 (6) |
N3 | 0.0193 (6) | 0.0360 (8) | 0.0162 (7) | 0.0046 (5) | 0.0104 (6) | 0.0030 (5) |
C4 | 0.0182 (7) | 0.0276 (8) | 0.0213 (8) | 0.0039 (6) | 0.0089 (7) | 0.0023 (6) |
C5 | 0.0230 (7) | 0.0254 (8) | 0.0273 (8) | 0.0045 (6) | 0.0151 (7) | 0.0027 (6) |
C6 | 0.0252 (7) | 0.0233 (8) | 0.0264 (8) | 0.0024 (6) | 0.0172 (7) | 0.0022 (6) |
C7 | 0.0299 (9) | 0.0330 (9) | 0.0442 (11) | −0.0031 (7) | 0.0206 (9) | −0.0078 (8) |
C8 | 0.0298 (9) | 0.0410 (10) | 0.0232 (9) | 0.0098 (7) | 0.0097 (8) | 0.0067 (8) |
C9 | 0.0365 (9) | 0.0395 (10) | 0.0301 (9) | 0.0075 (7) | 0.0216 (8) | −0.0014 (8) |
C11 | 0.0222 (7) | 0.0256 (8) | 0.0157 (7) | 0.0024 (6) | 0.0116 (6) | 0.0015 (6) |
C12 | 0.0222 (7) | 0.0234 (8) | 0.0223 (8) | −0.0024 (6) | 0.0114 (7) | −0.0016 (6) |
C13 | 0.0270 (8) | 0.0230 (8) | 0.0246 (8) | 0.0004 (6) | 0.0148 (7) | 0.0034 (6) |
C14 | 0.0244 (7) | 0.0286 (8) | 0.0153 (7) | 0.0039 (6) | 0.0101 (6) | 0.0024 (6) |
C15 | 0.0259 (8) | 0.0291 (8) | 0.0198 (8) | −0.0044 (6) | 0.0097 (7) | −0.0026 (7) |
C16 | 0.0294 (8) | 0.0248 (8) | 0.0226 (8) | −0.0040 (6) | 0.0146 (7) | 0.0006 (6) |
S1—C2 | 1.6904 (15) | C8—H9A | 0.9800 |
Cl1—C14 | 1.7465 (16) | C8—H9B | 0.9800 |
N1—C2 | 1.374 (2) | C8—H9C | 0.9800 |
N1—C6 | 1.4327 (19) | C9—H8A | 0.9800 |
N1—C11 | 1.4462 (19) | C9—H8B | 0.9800 |
C2—N3 | 1.336 (2) | C9—H8C | 0.9800 |
N3—C4 | 1.482 (2) | C11—C12 | 1.382 (2) |
N3—H1 | 0.83 (2) | C11—C16 | 1.390 (2) |
C4—C5 | 1.504 (2) | C12—C13 | 1.397 (2) |
C4—C7 | 1.527 (2) | C12—H12 | 0.9500 |
C4—C8 | 1.534 (2) | C13—C14 | 1.382 (2) |
C5—C6 | 1.330 (2) | C13—H13 | 0.9500 |
C5—H5 | 0.9500 | C14—C15 | 1.381 (2) |
C6—C9 | 1.502 (2) | C15—C16 | 1.393 (2) |
C7—H7A | 0.9800 | C15—H15 | 0.9500 |
C7—H7B | 0.9800 | C16—H16 | 0.9500 |
C7—H7C | 0.9800 | ||
C2—N1—C6 | 120.78 (13) | H9A—C8—H9B | 109.5 |
C2—N1—C11 | 119.87 (12) | C4—C8—H9C | 109.5 |
C6—N1—C11 | 119.30 (13) | H9A—C8—H9C | 109.5 |
N3—C2—N1 | 116.59 (13) | H9B—C8—H9C | 109.5 |
N3—C2—S1 | 121.92 (13) | C6—C9—H8A | 109.5 |
N1—C2—S1 | 121.46 (11) | C6—C9—H8B | 109.5 |
C2—N3—C4 | 124.65 (15) | H8A—C9—H8B | 109.5 |
C2—N3—H1 | 114.6 (14) | C6—C9—H8C | 109.5 |
C4—N3—H1 | 117.4 (13) | H8A—C9—H8C | 109.5 |
N3—C4—C5 | 106.41 (13) | H8B—C9—H8C | 109.5 |
N3—C4—C7 | 109.73 (13) | C12—C11—C16 | 120.79 (14) |
C5—C4—C7 | 111.46 (15) | C12—C11—N1 | 118.79 (13) |
N3—C4—C8 | 107.47 (14) | C16—C11—N1 | 120.40 (14) |
C5—C4—C8 | 111.52 (14) | C11—C12—C13 | 119.95 (14) |
C7—C4—C8 | 110.09 (14) | C11—C12—H12 | 120.0 |
C6—C5—C4 | 122.23 (14) | C13—C12—H12 | 120.0 |
C6—C5—H5 | 118.9 | C14—C13—C12 | 118.71 (15) |
C4—C5—H5 | 118.9 | C14—C13—H13 | 120.6 |
C5—C6—N1 | 118.87 (15) | C12—C13—H13 | 120.6 |
C5—C6—C9 | 124.65 (15) | C15—C14—C13 | 121.88 (14) |
N1—C6—C9 | 116.40 (13) | C15—C14—Cl1 | 119.14 (12) |
C4—C7—H7A | 109.5 | C13—C14—Cl1 | 118.97 (13) |
C4—C7—H7B | 109.5 | C14—C15—C16 | 119.19 (14) |
H7A—C7—H7B | 109.5 | C14—C15—H15 | 120.4 |
C4—C7—H7C | 109.5 | C16—C15—H15 | 120.4 |
H7A—C7—H7C | 109.5 | C11—C16—C15 | 119.47 (15) |
H7B—C7—H7C | 109.5 | C11—C16—H16 | 120.3 |
C4—C8—H9A | 109.5 | C15—C16—H16 | 120.3 |
C4—C8—H9B | 109.5 | ||
C6—N1—C2—N3 | −9.4 (2) | C2—N1—C6—C9 | −159.70 (15) |
C11—N1—C2—N3 | 168.04 (14) | C11—N1—C6—C9 | 22.8 (2) |
C6—N1—C2—S1 | 168.43 (11) | C2—N1—C11—C12 | −87.68 (19) |
C11—N1—C2—S1 | −14.1 (2) | C6—N1—C11—C12 | 89.81 (18) |
N1—C2—N3—C4 | −19.9 (2) | C2—N1—C11—C16 | 93.85 (19) |
S1—C2—N3—C4 | 162.28 (12) | C6—N1—C11—C16 | −88.66 (19) |
C2—N3—C4—C5 | 36.3 (2) | C16—C11—C12—C13 | 1.1 (2) |
C2—N3—C4—C7 | −84.4 (2) | N1—C11—C12—C13 | −177.39 (14) |
C2—N3—C4—C8 | 155.86 (16) | C11—C12—C13—C14 | 0.1 (2) |
N3—C4—C5—C6 | −26.8 (2) | C12—C13—C14—C15 | −1.2 (3) |
C7—C4—C5—C6 | 92.80 (19) | C12—C13—C14—Cl1 | 177.54 (13) |
C8—C4—C5—C6 | −143.71 (17) | C13—C14—C15—C16 | 1.2 (3) |
C4—C5—C6—N1 | 3.6 (2) | Cl1—C14—C15—C16 | −177.54 (13) |
C4—C5—C6—C9 | −179.71 (16) | C12—C11—C16—C15 | −1.1 (3) |
C2—N1—C6—C5 | 17.2 (2) | N1—C11—C16—C15 | 177.36 (15) |
C11—N1—C6—C5 | −160.24 (15) | C14—C15—C16—C11 | −0.1 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H1···S1i | 0.83 (2) | 2.59 (2) | 3.4054 (16) | 169.1 (17) |
Symmetry code: (i) −x+1, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C13H15ClN2S |
Mr | 266.78 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 173 |
a, b, c (Å) | 20.6710 (18), 10.8343 (10), 14.8619 (13) |
β (°) | 126.026 (5) |
V (Å3) | 2691.9 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.42 |
Crystal size (mm) | 0.37 × 0.29 × 0.26 |
Data collection | |
Diffractometer | Stoe IPDS II two-circle diffractometer |
Absorption correction | Multi-scan (MULABS; Spek, 2009; Blessing, 1995) |
Tmin, Tmax | 0.861, 0.899 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7624, 2512, 2134 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.609 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.093, 1.02 |
No. of reflections | 2512 |
No. of parameters | 161 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.22, −0.39 |
Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP (Sheldrick, 2008).
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H1···S1i | 0.83 (2) | 2.59 (2) | 3.4054 (16) | 169.1 (17) |
Symmetry code: (i) −x+1, y, −z+1/2. |
Acknowledgements
The authors gratefully acknowledge a research grant from the Higher Education Commission of Pakistan under project No. 20-Miscel/R&D/00/3834.
References
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The title compound belongs to a novel and rare class of dihydropyrimidine-2-thiones. Their synthesis has been attracting widespread attention due to diverse pharmacological activities such as antibacterial (Alam et al., 2005), antitumour (Swamy et al., 2005), antioxidative (Sriram et al., 2006), analgesic and anti-inflammatory properties (Leite et al., 2006; Kappe, 2000). In addition, these compounds act as antihypertensive agents as well as calcium channel blockers and neuropeptide Y antagonists (Rovnyak et al., 1995). The formation of the closely related 4,4,6-trimethyl-1-phenyl-3,4-dihydropyrimidine-2(1H)-thione as a side product during the reaction of cinnamoyl isothiocyanate and aniline to afford the corresponding thiourea derivative has been reported (Yamin et al., 2005) The title compound was prepared by the reaction of 4-chloroaniline with 4-methylpent-3-en-2-one in presence of potassium thiocyanate in acetone.
The dihydropyrimidine ring of the title compound adopts an envelope conformation with five almost coplanar atoms (r.m.s. deviation 0.054 Å) and the carbon atom bearing the two methyl substituents deviating from this plane by 0.441 (2) Å. The best plane through the six ring atoms forms a dihedral angle of 89.42 (5)° with the phenyl ring. The crystal packing is characterized by centrosymmetric dimers connected by N—H···S hydrogen bonds.