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

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890

2-(Thio­phen-2-yl)-N-(4-{(E)-[2-(thio­phen-2-yl)eth­yl]imino­meth­yl}benzyl­­idene)ethanamine

aDepartment of Chemistry, University of Cape Town, Private Bag, Rondebosch 7707, South Africa, and bResearch Centre for Synthesis and Catalysis, Department of Chemistry, University of Johannesburg, PO Box 524 Auckland Park, Johannesburg 2006, South Africa
*Correspondence e-mail: harrychiririwa@yahoo.com

(Received 3 March 2011; accepted 15 March 2011; online 19 March 2011)

In the crystal of the centrosymmetric title compound, C20H20N2S2, mol­ecules are linked by head-to-tail C—H⋯N hydrogen bonds, resulting in chains extending along the a axis. Three additional C—H⋯π inter­molecular inter­actions give rise to a herringbone packing motif which extends along the c axis. The C—H⋯N inter­actions provide links between the sheets.

Related literature

For related literature on bidendate Schiff base ligands, see: Chakraborty et al. (1999[Chakraborty, S., Munshi, P. & Lahiri, G. K. (1999). Polyhedron, 18, 1437-1444.]); Haga & Koizumi (1985[Haga, M. & Koizumi, K. (1985). Inorg. Chim. Acta, 104, 47-50.]).

[Scheme 1]

Experimental

Crystal data
  • C20H20N2S2

  • Mr = 352.52

  • Monoclinic, C 2/c

  • a = 9.8592 (10) Å

  • b = 7.1533 (6) Å

  • c = 25.678 (2) Å

  • β = 96.646 (5)°

  • V = 1798.8 (3) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.30 mm−1

  • T = 173 K

  • 0.22 × 0.2 × 0.04 mm

Data collection
  • Nonius Kappa CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.925, Tmax = 0.988

  • 16248 measured reflections

  • 2230 independent reflections

  • 1679 reflections with I > 2σ(I)

  • Rint = 0.045

Refinement
  • R[F2 > 2σ(F2)] = 0.057

  • wR(F2) = 0.181

  • S = 1.08

  • 2230 reflections

  • 109 parameters

  • 14 restraints

  • H-atom parameters constrained

  • Δρmax = 0.80 e Å−3

  • Δρmin = −0.42 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 andCg2 are the centroids of the thio­phene and benzene rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C4—H4⋯N8i 0.95 2.61 3.514 (3) 159
C2—H2⋯Cg1ii 0.95 2.79 3.702 (3) 161
C6—H6ACg2iii 0.99 2.72 3.515 (3) 137
C6—H6ACg2iv 0.99 2.72 3.515 (3) 137
Symmetry codes: (i) [x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]; (ii) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]; (iii) x, y-1, z; (iv) [-x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z+1].

Data collection: COLLECT (Nonius, 1998[Nonius (1998). COLLECT. Nonius BV, Delft. The Netherlands.]); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]); data reduction: DENZO-SMN; 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: DIAMOND (Brandenburg & Putz, 2005[Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]) and ORTEP-3 (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


Comment top

The title compound belongs to a class of tetradentate ligands. To the best of our knowledge, this is the first example of a neutral thiophenyldimine-based bridging ligand. This compound is a potential tetra-coordinate ligand but on complexation the compound will probably behave as a bidentate ligand as the sulfur, on the thiophene, has weak donor capacity towards co-ordination for majority of metal ions. Besides its use as a ligand, it is interesting from the crystal engineering point of view for the analysis of the packing mode of (I).

Compound (I) crystallizes with half a molecule in the asymmetric unit, with the other half generated through symmetry located in the center of the phenyl ring (Fig. 1). The phenyl ring together with the atoms C7—N8—C9 and the thiophene ring together with the atom C6 are planar with N8 and C5 deviating the most from the planes by 0.018 (2) Å and 0.010 (2) Å respectively. The two planes are close to parallel, the angle between them being 9.3 (1)°. Bond distances and angles in (I) are as expected from the chemical bonding.

The crystal structure of (I) is composed of head-to-tail C—H···N hydrogen bonded chains (Table 1) that extend in the crystallographic a axis (Fig. 2). Additionally, the phenyl and thiophen rings are involved in C—H···π intermolecular interactions that result in a herringbone motif that spreads along the crystallographic c axis (Fig. 3). The C—H···N interactions are found to connect these herringbone sheets along the a axis.,

Related literature top

For related literature [on what subject(s)?], see: Chakraborty et al. (1999); Haga & Koizumi (1985).

Experimental top

A solution of benzene 1,4-dicarboxaldehyde (0.50 g, 3.73 mmol) in methanol (10 ml) was added dropwise to a stirred solution of 2-thiophenylethylamine (0.95 g, 7.42 mmol) in methanol (10 ml). The mixture was stirred at room temperature for ca 16 h. The precipitate was filtered off and washed with diethylether and dried under vacuum for 4 h affording a fine shiny white powder in 80% yield. M.p.: 240–242 °C. Recrystallization was done by slow diffusion of Et2O into a concentrated CH2Cl2 solution of the white powder to give colorless crystals fo (I).

Refinement top

The methine and aromatic H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C—H = 0.95 Å and Uiso(H) = 1.2Ueq(C) for aromatic, C—H = 0.99 Å and Uiso(H) = 1.2Ueq(C) for CH2 C—H = 0.95 Å and Uiso(H) = 1.2Ueq(C) for CH.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005) and ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. View of (I) (50% probability displacement ellipsoids) with H atoms presented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. C—H···N hydrogen bond interactions in the crystal structure of (I). [Symmetry operators: (i) = -1/2 + x, 1/2 + y, z]
[Figure 3] Fig. 3. Sheets of C—H···π intermolecular interactions between molecules alligned along the bc face.
2-(Thiophen-2-yl)-N-(4-{(E)-[2-(thiophen-2- yl)ethyl]iminomethyl}benzylidene)ethanamine top
Crystal data top
C20H20N2S2F(000) = 744
Mr = 352.52Dx = 1.302 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 34223 reflections
a = 9.8592 (10) Åθ = 3.2–28.3°
b = 7.1533 (6) ŵ = 0.30 mm1
c = 25.678 (2) ÅT = 173 K
β = 96.646 (5)°Plate, colourless
V = 1798.8 (3) Å30.22 × 0.2 × 0.04 mm
Z = 4
Data collection top
Nonius Kappa CCD
diffractometer
Rint = 0.045
Graphite monochromatorθmax = 28.3°, θmin = 3.2°
1.0° ω scans, 60sh = 1313
16248 measured reflectionsk = 99
2230 independent reflectionsl = 3434
1679 reflections with I > 2σ(I)
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)] = 0.057Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.181H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0971P)2 + 3.1807P]
where P = (Fo2 + 2Fc2)/3
2230 reflections(Δ/σ)max < 0.001
109 parametersΔρmax = 0.80 e Å3
14 restraintsΔρmin = 0.42 e Å3
Crystal data top
C20H20N2S2V = 1798.8 (3) Å3
Mr = 352.52Z = 4
Monoclinic, C2/cMo Kα radiation
a = 9.8592 (10) ŵ = 0.30 mm1
b = 7.1533 (6) ÅT = 173 K
c = 25.678 (2) Å0.22 × 0.2 × 0.04 mm
β = 96.646 (5)°
Data collection top
Nonius Kappa CCD
diffractometer
1679 reflections with I > 2σ(I)
16248 measured reflectionsRint = 0.045
2230 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.05714 restraints
wR(F2) = 0.181H-atom parameters constrained
S = 1.08Δρmax = 0.80 e Å3
2230 reflectionsΔρmin = 0.42 e Å3
109 parameters
Special details top

Experimental. The intensity data was collected on a Nonius Kappa CCD diffractometer using an exposure time of 60 sec/per frame. Analytical data: IR (KBr): 1613?cm-1 (C=N, imine); 1H NMR: (CDCl3) δ H 8.23 (d, 2H) 7.76 (s, 2H) 7.13 (dd, 2H) 6.92 (dd, 2H) 6.84 (dd, 4H) 3.91 (dt, 4H) 3.25 (t, 4H); Anal. calcd. for C20H20N2S2: C, 68.14%; H, 5.72%; N, 7.95%; S, 18.19; Found: C, 68.19%; H, 5.52%; N, 7.72%; S, 18.44; EI—MS: m/z 351.76 [M]+;

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
S10.62222 (7)0.24504 (10)0.31079 (3)0.0357 (3)
C20.7356 (3)0.3763 (4)0.28220 (10)0.0400 (7)
H20.7110.46840.25620.048*
C30.8651 (3)0.3341 (4)0.30095 (10)0.0355 (6)
H30.94190.39550.28960.043*
C40.8766 (2)0.1915 (3)0.33866 (8)0.0194 (4)
H40.96070.14410.35520.023*
C50.7453 (2)0.1270 (3)0.34886 (9)0.0230 (5)
C60.7117 (3)0.0246 (3)0.38573 (10)0.0286 (5)
H6A0.76160.00050.42080.034*
H6B0.61280.02040.38910.034*
C70.7483 (3)0.2186 (3)0.36770 (10)0.0266 (5)
H7A0.84790.22660.3660.032*
H7B0.7010.24310.33220.032*
N80.7077 (2)0.3574 (3)0.40432 (8)0.0257 (5)
C90.8002 (2)0.4632 (3)0.42630 (9)0.0232 (5)
H90.8910.44740.41810.028*
C100.7729 (2)0.6096 (3)0.46404 (9)0.0220 (5)
C110.6408 (2)0.6450 (3)0.47609 (9)0.0235 (5)
H110.56610.57410.45980.028*
C120.8813 (2)0.7162 (3)0.48807 (9)0.0234 (5)
H120.97130.69350.47980.028*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0339 (4)0.0352 (4)0.0373 (4)0.0022 (3)0.0007 (3)0.0044 (3)
C20.073 (2)0.0227 (13)0.0245 (12)0.0002 (13)0.0045 (13)0.0058 (10)
C30.0487 (16)0.0284 (13)0.0314 (13)0.0127 (12)0.0133 (12)0.0009 (9)
C40.0167 (9)0.0190 (10)0.0217 (10)0.0007 (8)0.0012 (8)0.0046 (7)
C50.0288 (11)0.0183 (11)0.0230 (11)0.0037 (9)0.0073 (9)0.0019 (9)
C60.0396 (14)0.0218 (12)0.0262 (12)0.0020 (10)0.0118 (10)0.0013 (9)
C70.0309 (13)0.0223 (12)0.0282 (12)0.0010 (9)0.0096 (10)0.0063 (9)
N80.0293 (11)0.0214 (10)0.0269 (10)0.0010 (8)0.0055 (8)0.0061 (8)
C90.0260 (11)0.0207 (11)0.0238 (11)0.0007 (9)0.0073 (9)0.0010 (9)
C100.0269 (12)0.0181 (11)0.0211 (10)0.0002 (9)0.0028 (8)0.0003 (9)
C110.0236 (11)0.0220 (11)0.0248 (11)0.0024 (9)0.0026 (9)0.0030 (9)
C120.0200 (11)0.0245 (12)0.0263 (11)0.0009 (9)0.0048 (9)0.0015 (9)
Geometric parameters (Å, º) top
S1—C21.691 (3)C7—N81.455 (3)
S1—C51.693 (2)C7—H7A0.99
C2—C31.345 (4)C7—H7B0.99
C2—H20.95N8—C91.266 (3)
C3—C41.402 (4)C9—C101.472 (3)
C3—H30.95C9—H90.95
C4—C51.427 (3)C10—C111.397 (3)
C4—H40.95C10—C121.397 (3)
C5—C61.501 (3)C11—C12i1.388 (3)
C6—C71.520 (3)C11—H110.95
C6—H6A0.99C12—C11i1.388 (3)
C6—H6B0.99C12—H120.95
C2—S1—C593.55 (13)N8—C7—C6109.48 (19)
C3—C2—S1111.6 (2)N8—C7—H7A109.8
C3—C2—H2124.2C6—C7—H7A109.8
S1—C2—H2124.2N8—C7—H7B109.8
C2—C3—C4114.1 (2)C6—C7—H7B109.8
C2—C3—H3122.9H7A—C7—H7B108.2
C4—C3—H3122.9C9—N8—C7117.3 (2)
C3—C4—C5111.0 (2)N8—C9—C10122.8 (2)
C3—C4—H4124.5N8—C9—H9118.6
C5—C4—H4124.5C10—C9—H9118.6
C4—C5—C6128.3 (2)C11—C10—C12119.2 (2)
C4—C5—S1109.73 (17)C11—C10—C9121.4 (2)
C6—C5—S1121.93 (18)C12—C10—C9119.4 (2)
C5—C6—C7113.0 (2)C12i—C11—C10119.9 (2)
C5—C6—H6A109C12i—C11—H11120
C7—C6—H6A109C10—C11—H11120
C5—C6—H6B109C11i—C12—C10120.8 (2)
C7—C6—H6B109C11i—C12—H12119.6
H6A—C6—H6B107.8C10—C12—H12119.6
C5—S1—C2—C30.4 (2)C5—C6—C7—N8177.7 (2)
S1—C2—C3—C40.9 (3)C6—C7—N8—C9121.8 (2)
C2—C3—C4—C51.1 (3)C7—N8—C9—C10179.9 (2)
C3—C4—C5—C6179.2 (2)N8—C9—C10—C112.7 (4)
C3—C4—C5—S10.8 (2)N8—C9—C10—C12177.7 (2)
C2—S1—C5—C40.25 (18)C12—C10—C11—C12i0.5 (4)
C2—S1—C5—C6178.7 (2)C9—C10—C11—C12i179.9 (2)
C4—C5—C6—C769.3 (3)C11—C10—C12—C11i0.6 (4)
S1—C5—C6—C7108.9 (2)C9—C10—C12—C11i179.9 (2)
Symmetry code: (i) x+3/2, y+3/2, z+1.
Hydrogen-bond geometry (Å, º) top
Cg1 andCg2 are the centroids of the thiophene and benzene rings, respectively.
D—H···AD—HH···AD···AD—H···A
C4—H4···N8ii0.952.613.514 (3)159
C2—H2···Cg1iii0.952.793.702 (3)161
C6—H6A···Cg2iv0.992.723.515 (3)137
C6—H6A···Cg2v0.992.723.515 (3)137
Symmetry codes: (ii) x+1/2, y1/2, z; (iii) x+3/2, y1/2, z+1/2; (iv) x, y1, z; (v) x+3/2, y+1/2, z+1.

Experimental details

Crystal data
Chemical formulaC20H20N2S2
Mr352.52
Crystal system, space groupMonoclinic, C2/c
Temperature (K)173
a, b, c (Å)9.8592 (10), 7.1533 (6), 25.678 (2)
β (°) 96.646 (5)
V3)1798.8 (3)
Z4
Radiation typeMo Kα
µ (mm1)0.30
Crystal size (mm)0.22 × 0.2 × 0.04
Data collection
DiffractometerNonius Kappa CCD
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
16248, 2230, 1679
Rint0.045
(sin θ/λ)max1)0.668
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.057, 0.181, 1.08
No. of reflections2230
No. of parameters109
No. of restraints14
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.80, 0.42

Computer programs: COLLECT (Nonius, 1998), DENZO-SMN (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005) and ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
Cg1 andCg2 are the centroids of the thiophene and benzene rings, respectively.
D—H···AD—HH···AD···AD—H···A
C4—H4···N8i0.952.613.514 (3)159
C2—H2···Cg1ii0.952.793.702 (3)161
C6—H6A···Cg2iii0.992.723.515 (3)137
C6—H6A···Cg2iv0.992.723.515 (3)137
Symmetry codes: (i) x+1/2, y1/2, z; (ii) x+3/2, y1/2, z+1/2; (iii) x, y1, z; (iv) x+3/2, y+1/2, z+1.
 

Acknowledgements

We gratefully acknowledge Mintek and Project AuTEK for funding this project.

References

First citationBrandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.  Google Scholar
First citationBruker (2007). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
First citationChakraborty, S., Munshi, P. & Lahiri, G. K. (1999). Polyhedron, 18, 1437–1444.  Web of Science CrossRef CAS Google Scholar
First citationFarrugia, L. J. (1997). J. Appl. Cryst. 30, 565.  CrossRef IUCr Journals Google Scholar
First citationFarrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838.  CrossRef CAS IUCr Journals Google Scholar
First citationHaga, M. & Koizumi, K. (1985). Inorg. Chim. Acta, 104, 47–50.  CrossRef CAS Web of Science Google Scholar
First citationNonius (1998). COLLECT. Nonius BV, Delft. The Netherlands.  Google Scholar
First citationOtwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds