supplementary materials


sj5367 scheme

Acta Cryst. (2013). E69, o1761-o1762    [ doi:10.1107/S1600536813030560 ]

Ethyl 4-(4-chloro­anilino)-1-(4-chloro­phen­yl)-2-methyl-5-oxo-2,5-di­hydro-1H-pyrrole-2-carboxyl­ate

M. Akkurt, S. K. Mohamed, M. A. A. Elremaily, F. Santoyo-Gonzalez and M. R. Albayati

Abstract top

In the title compound, C20H18Cl2N2O3, the dihedral angles between the central 2,5-di­hydro-1H-pyrrole ring and the phenyl rings are 74.87 (9) and 29.09 (9)°. Intra­molecular N-H...O and C-H...O hydrogen bonds occur. In the crystal, pairs of N-H...O hydrogen bonds link adjacent mol­ecules into inversion dimers and form an R12(6)R22(10)R12(6) ring motif through C-H...O hydrogen bonds.

Comment top

Lactam compounds or 2-pyrrolidinones are the aza analogues of lactones. Lactams have received relatively little attention in spite of the fact that they are potentially more effective in a pharmaceutical sense, due to the lower toxicity of the lactam ring with respect to that of the lactone (Dembélé et al., 1992). A number of substances based on the γ-lactam structure have been found in an array of natural products and act as advanced intermediates for the synthesis of many biologically important compounds such as antibiotic and anticancer agents (Nay et al., 2009; Galeazzi et al., 1996; Ghelfi et al., 1999; Hanessian et al., 1996). Also, lactams themselves exhibit interesting biological and pharmacological properties, such as psychotropic, antihypertensive and antimuscarinic activity (Bergmann & Gericke 1990; Moody & Young 1994; Nilsson et al., 1990). Based on such facts, and as an extension of our work on the production γ- lactams, we report in this study the synthesis and crystal structure of another dihydro-pyrrolone derivative.

The central 2,5-dihydro-1H-pyrrole ring (N1/C4–C7) of the title compound (I), (Fig. 1) makes dihedral angles of 74.87 (9) and 29.09 (9)° with the two phenyl rings (C8···C13 and C15···C20), respectively. All bond lengths and bond angles are normal and are similar to those found in a related compound (Akkurt et al., 2013).

In the crystal, pairs of adjacent molecules are linked through intermolecular N—H···O and C—H···O hydrogen bonds (Table 1), forming an inversion dimer with an R21(6)R22(10)R21(6) ring motif (Bernstein et al., 1995; Fig. 2). In the crystal structure, π-π and C—H···π interactions are not observed.

Related literature top

For the lower toxicity of the lactam ring in comparison to lactones, see: Dembélé et al. (1992). For the importance of lactams in the synthesis of significant bio-active molecules see: Nay et al. (2009); Galeazzi et al. (1996); Ghelfi et al. (1999); Hanessian et al. (1996). For the pharmacological properties of dihydropyrrolones, see: Bergmann & Gericke (1990); Moody & Young (1994); Nilsson et al. (1990). For a similar structure, see: Akkurt et al. (2013). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

A mixture of 254 mg (2 mmol) of 4-chloroaniline and 232 mg (2 mmol) of ethyl pyruvate was taken in presence of 8 mol % of Fe3O4 nanoparticles in 15 ml ethanol/water (v/v) and was irradiated in a microwave for 30 minutes. The reaction progress was monitored by TLC. After completion of the reaction, the precipitated solid was filtered off, washed with water and recrystallized from ethanol. Single crystals of the title compound were obtained via slow evaporation of an ethanolic solution at room temperature.

Refinement top

The C-bound H-atoms were positioned geometrically [C—H = 0.95, 0.98 and 0.99 Å for aromatic, methyl and methylene H, respectively], and refined by using a riding model, with Uiso(H) = xUeq(C), where x = 1.5 for methyl H, and x = 1.2 for the other H atoms. The N-bound H-atom was located from a difference Fourier map and refined freely.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.
[Figure 2] Fig. 2. A view of the hydrogen bonding (dotted lines) of the title compound in the unit cell. H atoms not involved in H bonding are omitted for clarity. [Symmetry codes: (a) -x, -y, 1 - z; (b) x, 1 + y, z; (c) 2 - x, 1 - y, -z].
Ethyl 4-(4-chloroanilino)-1-(4-chlorophenyl)-2-methyl-5-oxo-2,5-dihydro-1H-pyrrole-2-carboxylate top
Crystal data top
C20H18Cl2N2O3Z = 2
Mr = 405.26F(000) = 420
Triclinic, P1Dx = 1.423 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.8319 (3) ÅCell parameters from 6329 reflections
b = 12.3759 (6) Åθ = 2.3–30.1°
c = 13.5707 (6) ŵ = 0.37 mm1
α = 86.484 (2)°T = 100 K
β = 80.098 (2)°Prisms, colourless
γ = 78.671 (2)°0.48 × 0.08 × 0.03 mm
V = 945.69 (8) Å3
Data collection top
Bruker APEXII CCD
diffractometer
5316 independent reflections
Radiation source: sealed tube4054 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.034
φ and ω scansθmax = 30.5°, θmin = 2.2°
Absorption correction: numerical
(SADABS; Bruker, 2005)
h = 88
Tmin = 0.967, Tmax = 0.990k = 1716
15209 measured reflectionsl = 1919
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.045 W = 1/[Σ2(FO2) + (0.044P)2 + 0.5765P]
where P = (FO2 + 2FC2)/3
wR(F2) = 0.107(Δ/σ)max = 0.001
S = 1.02Δρmax = 0.42 e Å3
5316 reflectionsΔρmin = 0.26 e Å3
250 parameters
Crystal data top
C20H18Cl2N2O3γ = 78.671 (2)°
Mr = 405.26V = 945.69 (8) Å3
Triclinic, P1Z = 2
a = 5.8319 (3) ÅMo Kα radiation
b = 12.3759 (6) ŵ = 0.37 mm1
c = 13.5707 (6) ÅT = 100 K
α = 86.484 (2)°0.48 × 0.08 × 0.03 mm
β = 80.098 (2)°
Data collection top
Bruker APEXII CCD
diffractometer
5316 independent reflections
Absorption correction: numerical
(SADABS; Bruker, 2005)
4054 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.990Rint = 0.034
15209 measured reflectionsθmax = 30.5°
Refinement top
R[F2 > 2σ(F2)] = 0.045H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.107Δρmax = 0.42 e Å3
S = 1.02Δρmin = 0.26 e Å3
5316 reflectionsAbsolute structure: ?
250 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

Refinement. Refinement on F2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The observed criterion of F2 > σ(F2) is used only for calculating -R-factor-obs 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
Cl10.31063 (8)0.07225 (4)0.69233 (3)0.0308 (1)
Cl21.25672 (8)0.72550 (4)0.02289 (3)0.0295 (1)
O10.5731 (2)0.12044 (10)0.17897 (9)0.0241 (3)
O20.6786 (2)0.14299 (10)0.32697 (9)0.0236 (3)
O30.3146 (2)0.43138 (9)0.48510 (8)0.0202 (3)
N10.2726 (2)0.30149 (11)0.37842 (10)0.0170 (3)
N20.5923 (3)0.51847 (11)0.32002 (11)0.0189 (4)
C10.7355 (4)0.03397 (17)0.07524 (16)0.0357 (6)
C20.7738 (3)0.02748 (15)0.16086 (15)0.0289 (5)
C30.5515 (3)0.17059 (13)0.26519 (12)0.0190 (4)
C40.3517 (3)0.27458 (13)0.27306 (12)0.0184 (4)
C50.4781 (3)0.36851 (13)0.23366 (12)0.0189 (4)
C60.4865 (3)0.43147 (13)0.30866 (12)0.0170 (4)
C70.3497 (3)0.39131 (13)0.40231 (12)0.0160 (4)
C80.1309 (3)0.24248 (13)0.45108 (11)0.0163 (4)
C90.1047 (3)0.29019 (14)0.48361 (13)0.0209 (4)
C100.2422 (3)0.23718 (14)0.55733 (13)0.0218 (5)
C110.1409 (3)0.13768 (14)0.59758 (12)0.0201 (5)
C120.0925 (3)0.08893 (14)0.56566 (13)0.0242 (5)
C130.2296 (3)0.14242 (14)0.49218 (13)0.0212 (4)
C140.1474 (3)0.26393 (15)0.22100 (13)0.0234 (5)
C150.7471 (3)0.56641 (13)0.24775 (12)0.0176 (4)
C160.9122 (3)0.61854 (14)0.27971 (12)0.0212 (4)
C171.0685 (3)0.66771 (14)0.21109 (13)0.0237 (5)
C181.0587 (3)0.66457 (13)0.10993 (13)0.0215 (5)
C190.8948 (3)0.61546 (14)0.07666 (13)0.0238 (5)
C200.7376 (3)0.56599 (14)0.14567 (13)0.0222 (5)
H1A0.590600.064300.094400.0540*
H1B0.871000.094200.058200.0540*
H1C0.719900.016400.017100.0540*
H2A0.780200.021400.221300.0350*
H2B0.924800.054700.144000.0350*
H2N0.591 (3)0.5340 (16)0.3776 (15)0.017 (5)*
H50.541900.380600.165500.0230*
H90.171200.358900.455400.0250*
H100.403500.268800.579800.0260*
H120.158000.019900.593600.0290*
H130.390900.110500.470100.0250*
H14A0.072700.203400.252600.0350*
H14B0.206900.248700.150200.0350*
H14C0.030500.332900.226500.0350*
H160.917500.620300.349200.0250*
H171.180600.703000.233100.0280*
H190.888700.615300.007200.0290*
H200.624100.532000.123200.0270*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0291 (2)0.0339 (2)0.0272 (2)0.0135 (2)0.0079 (2)0.0061 (2)
Cl20.0299 (2)0.0307 (2)0.0238 (2)0.0092 (2)0.0092 (2)0.0045 (2)
O10.0237 (6)0.0222 (6)0.0228 (6)0.0007 (5)0.0025 (5)0.0028 (5)
O20.0181 (6)0.0245 (6)0.0262 (6)0.0013 (5)0.0016 (5)0.0013 (5)
O30.0212 (6)0.0213 (6)0.0175 (6)0.0061 (5)0.0007 (5)0.0008 (4)
N10.0167 (6)0.0174 (6)0.0153 (6)0.0042 (5)0.0023 (5)0.0008 (5)
N20.0232 (7)0.0200 (7)0.0135 (7)0.0082 (5)0.0011 (5)0.0007 (5)
C10.0359 (11)0.0322 (10)0.0355 (11)0.0059 (8)0.0063 (9)0.0096 (8)
C20.0246 (9)0.0249 (9)0.0311 (10)0.0019 (7)0.0063 (7)0.0046 (7)
C30.0163 (7)0.0185 (8)0.0205 (8)0.0057 (6)0.0035 (6)0.0012 (6)
C40.0185 (7)0.0194 (8)0.0161 (7)0.0049 (6)0.0018 (6)0.0002 (6)
C50.0206 (8)0.0175 (8)0.0167 (7)0.0042 (6)0.0016 (6)0.0031 (6)
C60.0142 (7)0.0167 (7)0.0181 (8)0.0015 (6)0.0006 (6)0.0039 (6)
C70.0126 (7)0.0156 (7)0.0184 (7)0.0010 (5)0.0012 (6)0.0021 (6)
C80.0159 (7)0.0180 (7)0.0145 (7)0.0052 (6)0.0009 (6)0.0007 (6)
C90.0171 (7)0.0196 (8)0.0244 (8)0.0018 (6)0.0015 (6)0.0020 (6)
C100.0135 (7)0.0252 (9)0.0247 (8)0.0024 (6)0.0012 (6)0.0011 (7)
C110.0195 (8)0.0230 (8)0.0172 (8)0.0082 (6)0.0027 (6)0.0013 (6)
C120.0234 (8)0.0207 (8)0.0249 (9)0.0020 (7)0.0013 (7)0.0064 (7)
C130.0151 (7)0.0216 (8)0.0232 (8)0.0007 (6)0.0024 (6)0.0039 (6)
C140.0208 (8)0.0267 (9)0.0222 (8)0.0041 (7)0.0029 (7)0.0010 (7)
C150.0192 (7)0.0133 (7)0.0178 (7)0.0016 (6)0.0018 (6)0.0016 (6)
C160.0244 (8)0.0229 (8)0.0154 (7)0.0071 (7)0.0023 (6)0.0015 (6)
C170.0232 (8)0.0247 (9)0.0230 (8)0.0083 (7)0.0017 (7)0.0016 (7)
C180.0222 (8)0.0175 (8)0.0209 (8)0.0032 (6)0.0053 (6)0.0040 (6)
C190.0330 (9)0.0212 (8)0.0151 (8)0.0048 (7)0.0002 (7)0.0037 (6)
C200.0272 (9)0.0199 (8)0.0199 (8)0.0073 (7)0.0034 (7)0.0033 (6)
Geometric parameters (Å, º) top
Cl1—C111.7431 (17)C15—C201.396 (2)
Cl2—C181.7496 (18)C15—C161.398 (2)
O1—C21.470 (2)C16—C171.387 (2)
O1—C31.333 (2)C17—C181.387 (2)
O2—C31.203 (2)C18—C191.377 (3)
O3—C71.2245 (19)C19—C201.395 (2)
N1—C41.463 (2)C1—H1A0.9800
N1—C71.354 (2)C1—H1B0.9800
N1—C81.434 (2)C1—H1C0.9800
N2—C61.370 (2)C2—H2A0.9900
N2—C151.401 (2)C2—H2B0.9900
N2—H2N0.82 (2)C5—H50.9500
C1—C21.498 (3)C9—H90.9500
C3—C41.553 (2)C10—H100.9500
C4—C51.518 (2)C12—H120.9500
C4—C141.516 (3)C13—H130.9500
C5—C61.332 (2)C14—H14A0.9800
C6—C71.493 (2)C14—H14B0.9800
C8—C91.391 (2)C14—H14C0.9800
C8—C131.386 (2)C16—H160.9500
C9—C101.387 (2)C17—H170.9500
C10—C111.381 (2)C19—H190.9500
C11—C121.382 (3)C20—H200.9500
C12—C131.387 (2)
C2—O1—C3115.02 (13)Cl2—C18—C17119.29 (13)
C4—N1—C7112.06 (13)C17—C18—C19121.37 (16)
C4—N1—C8126.06 (13)C18—C19—C20119.60 (16)
C7—N1—C8121.88 (13)C15—C20—C19120.01 (16)
C6—N2—C15127.47 (14)C2—C1—H1A109.00
C15—N2—H2N115.2 (13)C2—C1—H1B109.00
C6—N2—H2N115.5 (13)C2—C1—H1C109.00
O1—C2—C1107.00 (15)H1A—C1—H1B109.00
O1—C3—C4111.43 (14)H1A—C1—H1C109.00
O1—C3—O2124.67 (15)H1B—C1—H1C109.00
O2—C3—C4123.77 (15)O1—C2—H2A110.00
N1—C4—C5101.95 (12)O1—C2—H2B110.00
N1—C4—C3109.18 (13)C1—C2—H2A110.00
C3—C4—C14113.41 (14)C1—C2—H2B110.00
C5—C4—C14114.95 (14)H2A—C2—H2B109.00
C3—C4—C5104.40 (14)C4—C5—H5125.00
N1—C4—C14112.07 (14)C6—C5—H5125.00
C4—C5—C6110.04 (14)C8—C9—H9120.00
N2—C6—C5136.07 (16)C10—C9—H9120.00
N2—C6—C7115.09 (14)C9—C10—H10121.00
C5—C6—C7108.81 (15)C11—C10—H10120.00
O3—C7—N1126.42 (15)C11—C12—H12121.00
N1—C7—C6106.87 (13)C13—C12—H12120.00
O3—C7—C6126.70 (15)C8—C13—H13120.00
N1—C8—C13120.72 (15)C12—C13—H13120.00
N1—C8—C9118.79 (14)C4—C14—H14A109.00
C9—C8—C13120.41 (15)C4—C14—H14B109.00
C8—C9—C10119.87 (16)C4—C14—H14C109.00
C9—C10—C11118.95 (16)H14A—C14—H14B109.00
C10—C11—C12121.86 (16)H14A—C14—H14C109.00
Cl1—C11—C12118.95 (13)H14B—C14—H14C109.00
Cl1—C11—C10119.19 (14)C15—C16—H16120.00
C11—C12—C13118.99 (16)C17—C16—H16120.00
C8—C13—C12119.91 (16)C16—C17—H17120.00
C16—C15—C20119.27 (15)C18—C17—H17121.00
N2—C15—C16118.52 (15)C18—C19—H19120.00
N2—C15—C20122.19 (16)C20—C19—H19120.00
C15—C16—C17120.71 (15)C15—C20—H20120.00
C16—C17—C18119.03 (16)C19—C20—H20120.00
Cl2—C18—C19119.34 (13)
C3—O1—C2—C1166.64 (15)C3—C4—C5—C6108.42 (16)
C2—O1—C3—O21.9 (2)N1—C4—C5—C65.23 (18)
C2—O1—C3—C4174.18 (13)C4—C5—C6—C74.8 (2)
C7—N1—C8—C13103.74 (19)C4—C5—C6—N2172.91 (19)
C7—N1—C4—C53.72 (17)N2—C6—C7—O33.8 (3)
C8—N1—C4—C5176.48 (14)C5—C6—C7—N12.39 (19)
C7—N1—C4—C14127.16 (15)N2—C6—C7—N1175.86 (14)
C8—N1—C4—C1453.0 (2)C5—C6—C7—O3177.94 (17)
C4—N1—C8—C9107.33 (18)N1—C8—C13—C12177.09 (15)
C7—N1—C4—C3106.33 (15)N1—C8—C9—C10176.92 (15)
C8—N1—C4—C373.47 (19)C13—C8—C9—C100.3 (3)
C4—N1—C7—C61.14 (18)C9—C8—C13—C120.5 (3)
C4—N1—C7—O3178.53 (16)C8—C9—C10—C110.4 (3)
C8—N1—C7—O31.3 (3)C9—C10—C11—C120.8 (3)
C4—N1—C8—C1376.0 (2)C9—C10—C11—Cl1178.48 (13)
C8—N1—C7—C6179.05 (14)Cl1—C11—C12—C13178.25 (13)
C7—N1—C8—C972.9 (2)C10—C11—C12—C131.0 (3)
C15—N2—C6—C7173.96 (16)C11—C12—C13—C80.9 (3)
C6—N2—C15—C16152.75 (18)N2—C15—C16—C17179.68 (16)
C15—N2—C6—C53.7 (3)C20—C15—C16—C171.2 (3)
C6—N2—C15—C2028.8 (3)N2—C15—C20—C19179.60 (16)
O1—C3—C4—N1158.36 (13)C16—C15—C20—C191.2 (3)
O2—C3—C4—C14151.28 (17)C15—C16—C17—C180.1 (3)
O1—C3—C4—C593.24 (16)C16—C17—C18—Cl2179.53 (13)
O2—C3—C4—C582.87 (19)C16—C17—C18—C191.1 (3)
O2—C3—C4—N125.5 (2)Cl2—C18—C19—C20179.51 (13)
O1—C3—C4—C1432.62 (19)C17—C18—C19—C201.2 (3)
C14—C4—C5—C6126.70 (16)C18—C19—C20—C150.0 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O30.82 (2)2.471 (19)2.8187 (19)107.0 (15)
N2—H2N···O3i0.82 (2)2.12 (2)2.9158 (19)164.9 (18)
C12—H12···O2ii0.952.343.285 (2)176
C13—H13···O20.952.413.142 (2)134
C14—H14A···O2iii0.982.583.431 (2)146
C16—H16···O3i0.952.533.308 (2)139
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z+1; (iii) x1, y, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N2—H2N···O30.82 (2)2.471 (19)2.8187 (19)107.0 (15)
N2—H2N···O3i0.82 (2)2.12 (2)2.9158 (19)164.9 (18)
C12—H12···O2ii0.95002.34003.285 (2)176.00
C13—H13···O20.95002.41003.142 (2)134.00
C14—H14A···O2iii0.98002.58003.431 (2)146.00
C16—H16···O3i0.95002.53003.308 (2)139.00
Symmetry codes: (i) x+1, y+1, z+1; (ii) x+1, y, z+1; (iii) x1, y, z.
Acknowledgements top

Manchester Metropolitan University, Erciyes University and Granada University are gratefully acknowledged for supporting this study. The authors also thank José Romero Garzón, Centro de Instrumentación Científica, Universidad de Granada, for the data collection.

references
References top

Akkurt, M., Mohamed, S. K., Elremaily, M. A. A., Santoyo-Gonzalez, F. & Albayati, M. R. (2013). Acta Cryst. E69, o1757–o1758.

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