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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o2004
doi:10.1107/S1600536811024615

2-Ethyl-N-[(5-nitro­thio­phen-2-yl)methyl­­idene]aniline

Ümit Ceylan,a* Hasan Tanak,b Sümeyye Gümüşc and Erbil Ağarc

aDepartment of Physics, Faculty of Arts & Science, Ondokuz Mayıs University, TR-55139 Kurupelit-Samsun, Turkey, bDepartment of Physics, Faculty of Arts & Science, Amasya University, TR-55139 Kurupelit-Samsun, Turkey, and cDepartment of Chemistry, Faculty of Arts & Science, Ondokuz Mayıs University, 55139 Samsun, Turkey
*Correspondence e-mail: uceylan@omu.edu.tr

(Received 17 June 2011; accepted 22 June 2011; online 9 July 2011)

In the title compound, C13H12N2O2S, the dihedral angle between the benzene and thio­phene rings is 36.72 (8)°. An inter­molecular C—H⋯π inter­action contributes to the stability of the crystal structure.

Related literature

For the biological properties of Schiff bases, see: Barton & Ollis (1979[Barton, D. & Ollis, W. D. (1979). Comprehensive Organic Chemistry, Vol 2. Oxford: Pergamon.]); Layer (1963[Layer, R. W. (1963). Chem. Rev. 63, 489-510.]); Ingold (1969[Ingold, C. K. (1969). Structure and Mechanism in Organic Chemistry, 2nd ed. Ithaca, New York: Cornell University Press.]); for their industrial properties, see: Taggi et al. (2002[Taggi, A. E., Hafez, A. M., Wack, H., Young, B., Ferraris, D. & Lectka, T. (2002). J. Am. Chem. Soc. 124, 6626-6635.]) and for their reaction properties, see: Aydoğan et al. (2001[Aydoğan, F., Öcal, N., Turgut, Z. & Yolaçan, C. (2001). Bull. Korean Chem. Soc. 22, 476-480.]). For related structures, see: Ağar et al. (2010[Ağar, A., Tanak, H. & Yavuz, M. (2010). Mol. Phys. 108, 1759-1772.]); Tanak et al. (2010[Tanak, H., Ağar, A. & Yavuz, M. (2010). J. Mol. Model. 16, 577-587.]); Demirtaş et al. (2009[Demirtaş, G., Dege, N., Şekerci, M., Servi, S. & Dinçer, M. (2009). Acta Cryst. E65, o1668.]).

[Scheme 1]

Experimental

Crystal data

  • C13H12N2O2S

  • Mr = 260.31

  • Monoclinic, P 21 /c

  • a = 11.3578 (4) Å

  • b = 7.4923 (2) Å

  • c = 14.9676 (6) Å

  • β = 99.589 (3)°

  • V = 1255.89 (7) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.25 mm−1

  • T = 296 K

  • 0.54 × 0.41 × 0.23 mm
Data collection

  • Stoe IPDS 2 diffractometer

  • Absorption correction: integration (X-RED32; Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]) Tmin = 0.866, Tmax = 0.954

  • 12190 measured reflections

  • 2468 independent reflections

  • 2195 reflections with I > 2σ(I)

  • Rint = 0.040
Refinement

  • R[F2 > 2σ(F2)] = 0.032

  • wR(F2) = 0.087

  • S = 1.05

  • 2468 reflections

  • 176 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.14 e Å−3

  • Δρmin = −0.16 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C10–C13/S1 ring.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C7—H8⋯Cg1i 1.00 (2) 2.94 (2) 3.678 (2) 131.0 (15)
Symmetry code: (i) [-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: X-AREA (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002[Stoe & Cie (2002). X-AREA and X-RED32. Stoe & Cie, Darmstadt, Germany.]); 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, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811024615/vm2106sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811024615/vm2106Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811024615/vm2106Isup3.cml

checkCIF report


Comment top

Schiff bases, i.e., compounds having a double C=N bond, are used as starting materials in the synthesis of important drugs, such as antibiotics and antiallergic, antiphlogistic, and antitumor substances (Barton et al., 1979; Layer, 1963; Ingold 1969). On the industrial scale, they have a wide range of applications, such as dyes and pigments (Taggi et al., 2002). Schiff bases have also been employed as ligands for the complexation of metal ions (Aydoğan et al., 2001).

We report here the crystal structure of the title new Schiff base compound, (I). The molecular structure is not planar (Fig. 1); the dihedral angle between the C1—C6 benzene and the C10—C13/S1 nitrothiophene ring is 36.72 (8)°. The dihedral angle between the thiophene and nitro group is 3.55 (13)°. The length of the C9=N1 double bond is 1.2694 (18) Å, slightly shorter than standard 1.28 Å value of a C=N double bond and consistent with related structures (Ağar et al., 2010; Tanak et al., 2010; Demirtaş et al., 2009).

The crystal structure is stabilized by π···π stacking interaction (Cg(1)···Cg(2)i = 3.6618 (9) Å) and by an intermolecular C—H···π stacking interaction (C7–H8···Cg(1)i = 2.94 (2) Å) [symmetry code (i): 1 - x,-1/2 + y,1/2 - z; Cg(1) and Cg(2) are the centroids of rings C10—C13/S1 and C1—C6, respectively).

Related literature top

For the biological properties of Schiff bases, see: Barton & Ollis (1979); Layer (1963); Ingold (1969); for their industrial properties, see: Taggi et al. (2002) and for their reaction properties, see: Aydoğan et al. (2001). For related structures, see: Ağar et al. (2010); Tanak et al. (2010); Demirtaş et al. (2009).

Experimental top

The compound 2-[(2-ethylphenylimino)methyl]-5-nitrothiophene was prepared by reflux a mixture of a solution containing 5-nitro-2-thiophene-carboxaldehyde (0.025 g 0.160 mmol) in 20 ml ethanol and a solution containing 2-ethylaniline (0.032 g 0.160 mmol) in 20 ml ethanol. The reaction mixture was stirred for 1 h under reflux. The crystals of 2-[(2-ethylphenylimino)methyl]-5-nitrothiophene suitable for X-ray analysis were obtained from ethanol by slow evaporation (yield % 64; m.p 112–114 °C).

Refinement top

C-bound H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.96 Å and Uiso(H) = 1.2–1.5Ueq(C). The position of the H7, H8 and H9 atoms were obtained from a difference map of the electron density in the unit-cell and was refined freely.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED32 (Stoe & Cie, 2002); 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, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme and 50% probability diplacement ellipsoids.
2-Ethyl-N-[(5-nitrothiophen-2-yl)methylidene]aniline top
Crystal data top
C13H12N2O2SF(000) = 544
Mr = 260.31Dx = 1.377 Mg m−3
Monoclinic, P21/cMelting point = 385–387 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 11.3578 (4) ÅCell parameters from 18861 reflections
b = 7.4923 (2) Åθ = 1.8–28.0°
c = 14.9676 (6) ŵ = 0.25 mm−1
β = 99.589 (3)°T = 296 K
V = 1255.89 (7) Å3Prism, yellow
Z = 40.54 × 0.41 × 0.23 mm
Data collection top
Stoe IPDS 2
diffractometer		2468 independent reflections
Radiation source: fine-focus sealed tube2195 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.040
Detector resolution: 6.67 pixels mm-1θmax = 26.0°, θmin = 1.8°
rotation method scansh = −13→13
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)		k = −9→9
Tmin = 0.866, Tmax = 0.954l = −18→18
12190 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.087 w = 1/[σ2(Fo2) + (0.0438P)2 + 0.2213P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
2468 reflectionsΔρmax = 0.14 e Å−3
176 parametersΔρmin = −0.16 e Å−3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0197 (19)
Crystal data top
C13H12N2O2SV = 1255.89 (7) Å3
Mr = 260.31Z = 4
Monoclinic, P21/cMo Kα radiation
a = 11.3578 (4) ŵ = 0.25 mm−1
b = 7.4923 (2) ÅT = 296 K
c = 14.9676 (6) Å0.54 × 0.41 × 0.23 mm
β = 99.589 (3)°
Data collection top
Stoe IPDS 2
diffractometer		2468 independent reflections
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)		2195 reflections with I > 2σ(I)
Tmin = 0.866, Tmax = 0.954Rint = 0.040
12190 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0320 restraints
wR(F2) = 0.087H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.14 e Å−3
2468 reflectionsΔρmin = −0.16 e Å−3
176 parameters
Special details top

Experimental. 256 frames, detector distance = 100 mm

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
C130.75353 (12)0.1347 (2)0.42892 (10)0.0489 (3)
H90.5748 (13)0.056 (2)0.1442 (11)0.051 (4)*
H80.2532 (19)−0.043 (3)0.2366 (14)0.085 (6)*
H70.243 (2)0.157 (3)0.2581 (16)0.096 (7)*
S10.60815 (3)0.17034 (5)0.38059 (2)0.05021 (14)
N10.44485 (10)0.15763 (16)0.20080 (8)0.0464 (3)
C10.36158 (12)0.16196 (19)0.11890 (9)0.0457 (3)
C50.16094 (14)0.1298 (2)0.04281 (11)0.0600 (4)
H50.08150.10060.04330.072*
C110.75953 (12)0.0594 (2)0.28326 (10)0.0534 (4)
H110.79280.02150.23380.064*
C20.39465 (14)0.2164 (2)0.03818 (10)0.0567 (4)
H20.47380.24640.03680.068*
C60.24197 (12)0.11916 (19)0.12317 (10)0.0482 (3)
N20.78998 (12)0.1655 (2)0.52375 (9)0.0621 (4)
O20.89564 (11)0.1458 (2)0.55569 (9)0.0861 (4)
C100.64167 (12)0.10510 (19)0.27810 (9)0.0453 (3)
C120.82434 (12)0.0758 (2)0.37105 (11)0.0550 (4)
H120.90510.04960.38730.066*
C40.19440 (16)0.1820 (3)−0.03736 (11)0.0686 (5)
H40.13780.1873−0.08990.082*
C70.20824 (14)0.0661 (3)0.21248 (12)0.0601 (4)
O10.71418 (13)0.2089 (2)0.56818 (9)0.0905 (5)
C30.31134 (16)0.2266 (3)−0.04023 (11)0.0659 (4)
H30.33390.2632−0.09430.079*
C80.07793 (16)0.0419 (4)0.21480 (16)0.0947 (7)
H8A0.06720.00830.27480.142*
H8B0.0465−0.05000.17280.142*
H8C0.03660.15180.19820.142*
C90.55012 (12)0.10376 (19)0.19795 (10)0.0472 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C130.0404 (7)0.0530 (8)0.0504 (8)0.0000 (6)−0.0013 (6)0.0022 (6)
S10.0381 (2)0.0632 (3)0.0480 (2)0.00633 (15)0.00307 (13)0.00008 (16)
N10.0417 (6)0.0505 (7)0.0444 (6)−0.0007 (5)−0.0007 (5)0.0011 (5)
C10.0440 (7)0.0468 (7)0.0433 (7)0.0034 (6)−0.0012 (5)−0.0047 (6)
C50.0461 (8)0.0682 (10)0.0608 (9)0.0012 (7)−0.0058 (7)−0.0117 (8)
C110.0429 (7)0.0630 (9)0.0541 (8)0.0059 (7)0.0078 (6)0.0004 (7)
C20.0510 (8)0.0697 (10)0.0476 (8)0.0040 (7)0.0034 (6)0.0004 (7)
C60.0449 (7)0.0463 (7)0.0507 (8)0.0035 (6)0.0003 (6)−0.0065 (6)
N20.0560 (8)0.0724 (9)0.0530 (7)0.0014 (6)−0.0050 (6)−0.0027 (6)
O20.0582 (7)0.1187 (11)0.0706 (8)−0.0005 (7)−0.0210 (6)−0.0045 (8)
C100.0404 (7)0.0454 (7)0.0488 (7)0.0006 (5)0.0036 (5)0.0028 (6)
C120.0369 (7)0.0635 (9)0.0625 (9)0.0047 (6)0.0023 (6)0.0036 (7)
C40.0644 (10)0.0853 (12)0.0482 (8)0.0101 (8)−0.0137 (7)−0.0109 (8)
C70.0494 (8)0.0670 (10)0.0630 (9)0.0006 (7)0.0066 (7)0.0042 (8)
O10.0784 (9)0.1339 (13)0.0568 (7)0.0181 (8)0.0037 (6)−0.0176 (8)
C30.0673 (10)0.0848 (12)0.0429 (8)0.0100 (9)0.0014 (7)0.0000 (8)
C80.0552 (10)0.140 (2)0.0904 (14)−0.0003 (12)0.0176 (10)0.0205 (14)
C90.0457 (7)0.0493 (8)0.0451 (7)0.0005 (6)0.0034 (6)0.0006 (6)
Geometric parameters (Å, º) top
C13—C121.351 (2)C6—C71.504 (2)
C13—N21.430 (2)N2—O11.2164 (19)
C13—S11.7097 (14)N2—O21.2245 (17)
S1—C101.7122 (15)C10—C91.4508 (19)
N1—C91.2694 (18)C12—H120.9300
N1—C11.4185 (17)C4—C31.377 (3)
C1—C21.385 (2)C4—H40.9300
C1—C61.4077 (19)C7—C81.497 (2)
C5—C41.375 (3)C7—H81.00 (2)
C5—C61.390 (2)C7—H71.00 (2)
C5—H50.9300C3—H30.9300
C11—C101.3714 (19)C8—H8A0.9600
C11—C121.400 (2)C8—H8B0.9600
C11—H110.9300C8—H8C0.9600
C2—C31.382 (2)C9—H90.963 (16)
C2—H20.9300
C12—C13—N2125.78 (13)C9—C10—S1120.47 (10)
C12—C13—S1114.58 (11)C13—C12—C11110.75 (13)
N2—C13—S1119.63 (11)C13—C12—H12124.6
C13—S1—C1089.50 (7)C11—C12—H12124.6
C9—N1—C1118.32 (12)C5—C4—C3120.31 (14)
C2—C1—C6120.72 (13)C5—C4—H4119.8
C2—C1—N1121.47 (13)C3—C4—H4119.8
C6—C1—N1117.71 (12)C8—C7—C6116.85 (15)
C4—C5—C6122.17 (15)C8—C7—H8109.9 (12)
C4—C5—H5118.9C6—C7—H8110.3 (12)
C6—C5—H5118.9C8—C7—H7110.3 (13)
C10—C11—C12112.74 (14)C6—C7—H7107.2 (13)
C10—C11—H11123.6H8—C7—H7101.0 (17)
C12—C11—H11123.6C4—C3—C2119.19 (16)
C3—C2—C1120.70 (15)C4—C3—H3120.4
C3—C2—H2119.7C2—C3—H3120.4
C1—C2—H2119.7C7—C8—H8A109.5
C5—C6—C1116.91 (14)C7—C8—H8B109.5
C5—C6—C7123.67 (14)H8A—C8—H8B109.5
C1—C6—C7119.42 (13)C7—C8—H8C109.5
O1—N2—O2123.75 (15)H8A—C8—H8C109.5
O1—N2—C13118.15 (13)H8B—C8—H8C109.5
O2—N2—C13118.10 (14)N1—C9—C10121.28 (14)
C11—C10—C9127.10 (14)N1—C9—H9123.5 (9)
C11—C10—S1112.43 (11)C10—C9—H9115.2 (9)
C12—C13—S1—C10−0.24 (12)C12—C11—C10—C9179.87 (14)
N2—C13—S1—C10−179.44 (13)C12—C11—C10—S10.35 (17)
C9—N1—C1—C2−39.8 (2)C13—S1—C10—C11−0.07 (12)
C9—N1—C1—C6143.95 (14)C13—S1—C10—C9−179.63 (12)
C6—C1—C2—C3−1.2 (2)N2—C13—C12—C11179.62 (14)
N1—C1—C2—C3−177.40 (14)S1—C13—C12—C110.47 (18)
C4—C5—C6—C1−0.9 (2)C10—C11—C12—C13−0.5 (2)
C4—C5—C6—C7178.76 (16)C6—C5—C4—C3−0.2 (3)
C2—C1—C6—C51.6 (2)C5—C6—C7—C8−6.3 (3)
N1—C1—C6—C5177.94 (13)C1—C6—C7—C8173.42 (17)
C2—C1—C6—C7−178.07 (15)C5—C4—C3—C20.7 (3)
N1—C1—C6—C7−1.8 (2)C1—C2—C3—C40.0 (3)
C12—C13—N2—O1−175.78 (17)C1—N1—C9—C10176.56 (12)
S1—C13—N2—O13.3 (2)C11—C10—C9—N1−176.47 (14)
C12—C13—N2—O23.8 (2)S1—C10—C9—N13.0 (2)
S1—C13—N2—O2−177.09 (13)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C10–C13/S1 ring.
D—H···AD—HH···AD···AD—H···A
C7—H8···Cg1i1.00 (2)2.94 (2)3.678 (2)131.0 (15)
Symmetry code: (i) −x+1, y−1/2, −z+1/2.

Experimental details

Crystal data
Chemical formulaC13H12N2O2S
Mr260.31
Crystal system, space groupMonoclinic, P21/c
Temperature (K)296
a, b, c (Å)11.3578 (4), 7.4923 (2), 14.9676 (6)
β (°) 99.589 (3)
V (Å3)1255.89 (7)
Z4
Radiation typeMo Kα
µ (mm−1)0.25
Crystal size (mm)0.54 × 0.41 × 0.23
Data collection
DiffractometerStoe IPDS 2
diffractometer
Absorption correctionIntegration
(X-RED32; Stoe & Cie, 2002)
Tmin, Tmax0.866, 0.954
No. of measured, independent and
observed [I > 2σ(I)] reflections		12190, 2468, 2195
Rint0.040
(sin θ/λ)max (Å−1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.032, 0.087, 1.05
No. of reflections2468
No. of parameters176
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.14, −0.16

Computer programs: X-AREA (Stoe & Cie, 2002), X-RED32 (Stoe & Cie, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C10–C13/S1 ring.
D—H···AD—HH···AD···AD—H···A
C7—H8···Cg1i1.00 (2)2.94 (2)3.678 (2)131.0 (15)
Symmetry code: (i) −x+1, y−1/2, −z+1/2.
 

Acknowledgements

The authors thank Professor Dr Orhan Büyükgüngör for his help with the data collection and acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDS 2 diffractometer (purchased under grant No. F279 of the University Research Fund).

References

First citationAğar, A., Tanak, H. & Yavuz, M. (2010). Mol. Phys. 108, 1759–1772.  Google Scholar
 First citationAydoğan, F., Öcal, N., Turgut, Z. & Yolaçan, C. (2001). Bull. Korean Chem. Soc. 22, 476–480.  CAS Google Scholar
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ISSN: 2056-9890
Volume 67| Part 8| August 2011| Page o2004
doi:10.1107/S1600536811024615
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