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ISSN: 2056-9890

Ethyl 2-amino-4-(3-nitro­phen­yl)-4H-1-benzothieno[3,2-b]pyran-3-carboxyl­ate

aDépartement de Chimie, Faculté des Sciences, Dhar Mehraz, BP 1796 Atlas, 30000 Fes, Morocco, and bLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
*Correspondence e-mail: elyazidimohamed@hotmail.com

(Received 9 April 2014; accepted 15 April 2014; online 18 April 2014)

The mol­ecule of the title compound, C20H16N2O5S, is built up by one fused five-membered and two fused six-membered rings linked to eth­oxy­carbonyl and 3-nitro­phenyl groups. The benzothieno­pyran ring system is nearly planar (r.m.s deviation = 0.0392 Å) and forms a dihedral angle of 86.90 (6)° with the aromatic ring of the nitro­benzene group. In the crystal, mol­ecules are linked by N—H⋯O hydrogen bonds and by ππ inter­actions between the phenyl ring and the six-membered heterocyle [inter­centroid distance = 3.5819 (8) Å], forming a three-dimensional network.

Related literature

For background to the organic synthesis of the title compound, see: House (1972[House, H. O. (1972). Modern Synthetic Reactions, 2nd ed., pp. 581-595. New York: Benjamin.]); Kabashima et al. (2000[Kabashima, H., Tsuji, H., Shibuya, T. & Hattori, H. (2000). J. Mol. Catal. A Chem. 155, 23-29.]); Jung (1991[Jung, M. E. (1991). Comprehensive Organic Synthesis, Vol. 4, edited by B. M. Trost, I. Fleming & M. F. Semmelhack, pp. 1-68. Oxford: Pergamon Press.]). For the preparation of heterocyclic compounds using condensation reactions, see: Boughaleb et al. (2011[Boughaleb, A., Zouihri, H., Gmouh, S., Kerbal, A. & El yazidi, M. (2011). Acta Cryst. E67, o2106.]); Cabiddu et al. (2002[Cabiddu, M. G., Cabiddu, S., Cadoni, E., De Montis, S., Fattuoni, C., Melis, S. & Usai, M. (2002). Synthesis, 7, 875-878.]); Pradhan & Asish (2005[Pradhan, T. K. & Asish, D. (2005). Tetrahedron Lett. 61, 9007-9017.]).

[Scheme 1]

Experimental

Crystal data
  • C20H16N2O5S

  • Mr = 396.41

  • Triclinic, [P \overline 1]

  • a = 8.3670 (2) Å

  • b = 9.4319 (2) Å

  • c = 12.8948 (4) Å

  • α = 102.505 (1)°

  • β = 106.493 (1)°

  • γ = 94.840 (1)°

  • V = 940.96 (4) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.21 mm−1

  • T = 296 K

  • 0.42 × 0.31 × 0.26 mm

Data collection
  • Bruker X8 APEX diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.673, Tmax = 0.746

  • 20668 measured reflections

  • 4857 independent reflections

  • 3954 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.137

  • S = 1.05

  • 4857 reflections

  • 253 parameters

  • H-atom parameters constrained

  • Δρmax = 0.37 e Å−3

  • Δρmin = −0.25 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1B⋯O2 0.86 2.09 2.6950 (17) 127
N1—H1B⋯O2i 0.86 2.30 3.0327 (17) 143
N1—H1A⋯O5ii 0.86 2.30 3.1489 (19) 169
Symmetry codes: (i) -x+1, -y+2, -z; (ii) x+1, y+1, z.

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]) and publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information


Comment top

The Michael reaction is one of the most efficient methods for effecting carbon–carbon bond formation and has wide synthetic applications (House, 1972; Kabashima et al., 2000). This reaction and its close variants have been extensively used in organic synthesis (Jung, 1991). Generally, Michael additions are conducted in a suitable solvent in the presence of a strong base either at room or at elevated temperatures. In continuing our previous works on the preparation of hetrocyclic compounds by using condensation reactions (Boughaleb et al., 2011), we now wish to describe the behavior of ethylcyanoacetate with respect to (Z)-2-(3-nitrobenzylidene)-1-benzo[b]thiophen-3(2H)-one and derivatives in ethanol, with the presence of piperidine as a basic catalyst (Cabiddu et al., 2002; Pradhan & Asish, 2005). We have shown that cyclocondensation start with a Michael 1,4-additon, followed by intramolecular cyclization via nucleophilic addition of the hydroxyl group to the cyano group and not onto the carboxylate, to afford the tricyclic heterocycle ethyl2-amino-4-(3-nitrophenyl)-4H-1-benzothieno[3,2-b]pyran-3-carboxylate.

The molecule of the title compound, is formed by tree fused rings linked to an ethyl-3-carboxylate nd a 3-nitrophenyl group as shown in Fig. 1. The three fused rings (S1/C1–C11/O1) are almost coplanar, with the maximum deviation from the mean plane of -0.089 (2) Å at C9, and make a dihedral angle of 86.90 (6)° with the plane through the attached nitrophenyl group.

In the crystal, molecules are linked by N—H···O hydrogen bonds and by ππ interactions in a three-dimensional network as shown in Fig. 2 and Table 1.

Related literature top

For background to the organic synthesis of the title compound, see: House (1972); Kabashima et al. (2000); Jung (1991). For the preparation of hetrocyclic compounds using condensation reactions, see: Boughaleb et al. (2011); Cabiddu et al. (2002); Pradhan & Asish (2005).

Experimental top

In a 100 ml flask equipped with a condenser was dissolved 4 mmol of (Z)-2-(3-nitrobenzylidene)-1-benzo[b]thiophen-3(2H)-one and 5 mmol of ethyl cyanoacetate in 30 ml of ethanol. Then, 1 ml of piperidine was added, and the reaction mixture was refluxed for 6 h. Thin layer chromatography revealed the formation of a single product. The organic phase was evaporated under reduce pressure. The resulting residue was recristallized from ethanol (Yield: 68%; m.p.: 493 K).

Refinement top

H atoms were located in a difference map and treated as riding with C–H = 0.93–0.97 Å, N–H = 0.86 Å, and with Uiso(H) = 1.2 Ueq(C, N) or Uiso(H) = 1.5 Ueq(C) for methyl H atoms. Two ouliers (0 0 1, 0 1 0) were omitted in the last cycles of refinement.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as small circles.
[Figure 2] Fig. 2. Partial crystal packing for the title compound showing molecules linked by hydrogen bonds (dashed lines).
Ethyl 2-amino-4-(3-nitrophenyl)-4H-1-benzothieno[3,2-b]pyran-3-carboxylate top
Crystal data top
C20H16N2O5SZ = 2
Mr = 396.41F(000) = 412
Triclinic, P1Dx = 1.399 Mg m3
Hall symbol: -P 1Melting point: 493 K
a = 8.3670 (2) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.4319 (2) ÅCell parameters from 4857 reflections
c = 12.8948 (4) Åθ = 2.5–28.7°
α = 102.505 (1)°µ = 0.21 mm1
β = 106.493 (1)°T = 296 K
γ = 94.840 (1)°Block, colourless
V = 940.96 (4) Å30.42 × 0.31 × 0.26 mm
Data collection top
Bruker X8 APEX
diffractometer
4857 independent reflections
Radiation source: fine-focus sealed tube3954 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ϕ and ω scansθmax = 28.7°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 1111
Tmin = 0.673, Tmax = 0.746k = 1212
20668 measured reflectionsl = 1717
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.137H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0782P)2 + 0.1615P]
where P = (Fo2 + 2Fc2)/3
4857 reflections(Δ/σ)max = 0.001
253 parametersΔρmax = 0.37 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
C20H16N2O5Sγ = 94.840 (1)°
Mr = 396.41V = 940.96 (4) Å3
Triclinic, P1Z = 2
a = 8.3670 (2) ÅMo Kα radiation
b = 9.4319 (2) ŵ = 0.21 mm1
c = 12.8948 (4) ÅT = 296 K
α = 102.505 (1)°0.42 × 0.31 × 0.26 mm
β = 106.493 (1)°
Data collection top
Bruker X8 APEX
diffractometer
4857 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
3954 reflections with I > 2σ(I)
Tmin = 0.673, Tmax = 0.746Rint = 0.025
20668 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.137H-atom parameters constrained
S = 1.05Δρmax = 0.37 e Å3
4857 reflectionsΔρmin = 0.25 e Å3
253 parameters
Special details top

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
C11.03581 (19)0.74569 (16)0.51586 (12)0.0444 (3)
C21.1714 (2)0.7184 (2)0.59752 (14)0.0572 (4)
H21.15390.66460.64690.069*
C31.3318 (2)0.7739 (2)0.60256 (14)0.0596 (4)
H31.42390.75660.65610.072*
C41.3590 (2)0.8552 (2)0.52938 (14)0.0553 (4)
H41.46890.89080.53470.066*
C51.22638 (19)0.88383 (17)0.44927 (13)0.0472 (3)
H51.24550.93880.40100.057*
C61.06239 (17)0.82841 (14)0.44214 (11)0.0388 (3)
C70.90329 (17)0.83869 (14)0.36665 (11)0.0366 (3)
C80.76677 (17)0.76734 (14)0.37893 (11)0.0373 (3)
C90.59063 (16)0.75463 (14)0.30354 (11)0.0356 (3)
H90.52050.79430.34870.043*
C100.59569 (16)0.84817 (14)0.22130 (11)0.0361 (3)
C110.74244 (17)0.91953 (14)0.21693 (11)0.0371 (3)
C120.43789 (18)0.86851 (15)0.14814 (12)0.0418 (3)
C130.1380 (2)0.8102 (3)0.0990 (2)0.0859 (7)
H13A0.13890.80110.02280.103*
H13B0.10310.90340.12480.103*
C140.0200 (2)0.6887 (2)0.1031 (2)0.0785 (6)
H14A0.09140.69100.05640.118*
H14B0.01920.69880.17870.118*
H14C0.05490.59690.07700.118*
C150.51766 (16)0.59335 (14)0.24462 (11)0.0363 (3)
C160.5980 (2)0.50862 (16)0.17907 (13)0.0486 (3)
H160.69690.55070.17100.058*
C170.5336 (2)0.36266 (18)0.12555 (16)0.0598 (4)
H170.58950.30770.08200.072*
C180.3863 (2)0.29794 (17)0.13649 (15)0.0592 (5)
H180.34140.20000.10080.071*
C190.30905 (19)0.38353 (17)0.20176 (14)0.0516 (4)
C200.37110 (17)0.52953 (16)0.25679 (12)0.0439 (3)
H200.31550.58350.30100.053*
N10.75846 (17)0.99963 (14)0.14576 (11)0.0500 (3)
H1A0.85691.03940.14940.060*
H1B0.67041.01140.09630.060*
N20.1493 (2)0.3189 (2)0.21188 (16)0.0745 (5)
O10.89774 (12)0.91629 (11)0.28705 (8)0.0435 (2)
O20.41926 (14)0.93260 (13)0.07393 (10)0.0551 (3)
O30.30471 (13)0.80479 (15)0.16981 (11)0.0597 (3)
O40.0661 (2)0.3993 (2)0.2526 (2)0.1098 (7)
O50.1064 (2)0.1868 (2)0.17700 (19)0.1165 (7)
S10.82193 (5)0.68473 (5)0.48947 (3)0.05225 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0450 (7)0.0467 (7)0.0397 (7)0.0057 (6)0.0084 (6)0.0138 (6)
C20.0577 (10)0.0676 (10)0.0468 (8)0.0126 (8)0.0067 (7)0.0273 (7)
C30.0479 (9)0.0773 (11)0.0482 (9)0.0150 (8)0.0012 (7)0.0211 (8)
C40.0391 (8)0.0712 (10)0.0487 (9)0.0056 (7)0.0063 (6)0.0119 (7)
C50.0410 (7)0.0539 (8)0.0423 (7)0.0017 (6)0.0072 (6)0.0130 (6)
C60.0404 (7)0.0371 (6)0.0342 (6)0.0037 (5)0.0068 (5)0.0064 (5)
C70.0392 (7)0.0346 (6)0.0343 (6)0.0025 (5)0.0082 (5)0.0107 (5)
C80.0394 (7)0.0373 (6)0.0343 (6)0.0030 (5)0.0083 (5)0.0126 (5)
C90.0349 (6)0.0380 (6)0.0360 (6)0.0032 (5)0.0121 (5)0.0129 (5)
C100.0377 (7)0.0355 (6)0.0373 (6)0.0054 (5)0.0113 (5)0.0139 (5)
C110.0380 (6)0.0356 (6)0.0386 (7)0.0054 (5)0.0106 (5)0.0131 (5)
C120.0388 (7)0.0452 (7)0.0477 (8)0.0116 (5)0.0156 (6)0.0197 (6)
C130.0361 (9)0.1282 (19)0.1168 (18)0.0216 (10)0.0176 (10)0.0839 (16)
C140.0483 (10)0.0803 (13)0.0881 (15)0.0057 (9)0.0018 (10)0.0096 (11)
C150.0341 (6)0.0387 (6)0.0365 (6)0.0011 (5)0.0075 (5)0.0166 (5)
C160.0476 (8)0.0441 (7)0.0552 (9)0.0014 (6)0.0198 (7)0.0119 (6)
C170.0684 (11)0.0455 (8)0.0610 (10)0.0067 (7)0.0188 (9)0.0067 (7)
C180.0655 (10)0.0412 (7)0.0560 (9)0.0078 (7)0.0024 (8)0.0160 (7)
C190.0409 (7)0.0545 (8)0.0533 (8)0.0106 (6)0.0014 (6)0.0292 (7)
C200.0358 (7)0.0509 (7)0.0467 (8)0.0001 (6)0.0094 (6)0.0228 (6)
N10.0416 (6)0.0573 (7)0.0569 (8)0.0010 (5)0.0113 (6)0.0342 (6)
N20.0517 (9)0.0814 (11)0.0832 (11)0.0221 (8)0.0030 (8)0.0424 (9)
O10.0356 (5)0.0502 (5)0.0465 (5)0.0001 (4)0.0085 (4)0.0239 (4)
O20.0458 (6)0.0699 (7)0.0608 (7)0.0148 (5)0.0145 (5)0.0404 (6)
O30.0343 (5)0.0866 (8)0.0737 (8)0.0155 (5)0.0171 (5)0.0496 (7)
O40.0650 (10)0.1204 (15)0.1621 (19)0.0096 (10)0.0533 (12)0.0581 (14)
O50.0925 (12)0.0841 (11)0.1571 (18)0.0447 (9)0.0255 (12)0.0378 (11)
S10.0472 (2)0.0633 (3)0.0485 (2)0.00050 (17)0.00801 (16)0.03121 (18)
Geometric parameters (Å, º) top
C1—C21.396 (2)C12—O31.3482 (17)
C1—C61.405 (2)C13—O31.446 (2)
C1—S11.7449 (16)C13—C141.469 (3)
C2—C31.377 (3)C13—H13A0.9700
C2—H20.9300C13—H13B0.9700
C3—C41.392 (3)C14—H14A0.9600
C3—H30.9300C14—H14B0.9600
C4—C51.376 (2)C14—H14C0.9600
C4—H40.9300C15—C201.3843 (18)
C5—C61.397 (2)C15—C161.388 (2)
C5—H50.9300C16—C171.383 (2)
C6—C71.4338 (18)C16—H160.9300
C7—C81.3423 (18)C17—C181.386 (3)
C7—O11.3768 (15)C17—H170.9300
C8—C91.4959 (18)C18—C191.371 (3)
C8—S11.7378 (14)C18—H180.9300
C9—C101.5261 (17)C19—C201.384 (2)
C9—C151.5308 (17)C19—N21.473 (2)
C9—H90.9800C20—H200.9300
C10—C111.3712 (18)N1—H1A0.8600
C10—C121.4436 (19)N1—H1B0.8600
C11—N11.3356 (17)N2—O41.208 (3)
C11—O11.3633 (16)N2—O51.214 (2)
C12—O21.2195 (17)
C2—C1—C6120.99 (15)O3—C13—C14108.58 (16)
C2—C1—S1127.04 (13)O3—C13—H13A110.0
C6—C1—S1111.96 (11)C14—C13—H13A110.0
C3—C2—C1117.84 (16)O3—C13—H13B110.0
C3—C2—H2121.1C14—C13—H13B110.0
C1—C2—H2121.1H13A—C13—H13B108.4
C2—C3—C4121.46 (15)C13—C14—H14A109.5
C2—C3—H3119.3C13—C14—H14B109.5
C4—C3—H3119.3H14A—C14—H14B109.5
C5—C4—C3121.21 (16)C13—C14—H14C109.5
C5—C4—H4119.4H14A—C14—H14C109.5
C3—C4—H4119.4H14B—C14—H14C109.5
C4—C5—C6118.47 (15)C20—C15—C16119.01 (13)
C4—C5—H5120.8C20—C15—C9120.39 (12)
C6—C5—H5120.8C16—C15—C9120.59 (11)
C5—C6—C1120.03 (13)C17—C16—C15121.20 (15)
C5—C6—C7130.31 (13)C17—C16—H16119.4
C1—C6—C7109.65 (12)C15—C16—H16119.4
C8—C7—O1124.23 (12)C16—C17—C18120.27 (17)
C8—C7—C6115.68 (12)C16—C17—H17119.9
O1—C7—C6120.09 (11)C18—C17—H17119.9
C7—C8—C9124.19 (12)C19—C18—C17117.59 (14)
C7—C8—S1111.37 (10)C19—C18—H18121.2
C9—C8—S1124.38 (10)C17—C18—H18121.2
C8—C9—C10107.83 (10)C18—C19—C20123.38 (14)
C8—C9—C15110.43 (11)C18—C19—N2118.73 (15)
C10—C9—C15112.40 (10)C20—C19—N2117.87 (17)
C8—C9—H9108.7C19—C20—C15118.54 (15)
C10—C9—H9108.7C19—C20—H20120.7
C15—C9—H9108.7C15—C20—H20120.7
C11—C10—C12118.22 (12)C11—N1—H1A120.0
C11—C10—C9123.25 (12)C11—N1—H1B120.0
C12—C10—C9118.45 (11)H1A—N1—H1B120.0
N1—C11—O1109.61 (11)O4—N2—O5123.09 (19)
N1—C11—C10127.07 (13)O4—N2—C19118.92 (16)
O1—C11—C10123.32 (12)O5—N2—C19118.0 (2)
O2—C12—O3121.52 (13)C11—O1—C7116.95 (10)
O2—C12—C10126.91 (13)C12—O3—C13117.57 (13)
O3—C12—C10111.56 (12)C8—S1—C191.31 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O20.862.092.6950 (17)127
N1—H1B···O2i0.862.303.0327 (17)143
N1—H1A···O5ii0.862.303.1489 (19)169
Symmetry codes: (i) x+1, y+2, z; (ii) x+1, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1B···O20.862.092.6950 (17)127.3
N1—H1B···O2i0.862.303.0327 (17)143.0
N1—H1A···O5ii0.862.303.1489 (19)168.9
Symmetry codes: (i) x+1, y+2, z; (ii) x+1, y+1, z.
 

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

References

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