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

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ISSN: 2056-9890

N,N′-(Ethane-1,2-di­yl)di­benzene­carbo­thio­amide

aDepartment of Applied Chemistry and Biotechnology, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and bCenter for Analytical Instrumentation, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
*Correspondence e-mail: sasanuma@faculty.chiba-u.jp

(Received 5 April 2014; accepted 14 April 2014; online 18 April 2014)

The title compound, C16H16N2S2, adopts a gauche+gauche+gauche+ (g+g+g+) conformation in the NH—CH2—CH2—NH bond sequence. In the crystal, mol­ecules are connected by pairs of N—H⋯S=C hydrogen bonds and C—H⋯π inter­actions, forming a tape structure along the c-axis direction.

Related literature

For crystal structures and conformations of related compounds with –(C=X)–C6H4–(C=X)–Y–(CH2)m–Y– (X = O or S and Y = O, S, or NH) bond sequences, see for example,: Palmer & Brisse (1980[Palmer, A. & Brisse, F. (1980). Acta Cryst. B36, 1447-1452.]); Brisson & Brisse (1986[Brisson, J. & Brisse, F. (1986). Macromolecules, 19, 2632-2639.]); Abe et al. (2011[Abe, D., Sasanuma, Y. & Sato, H. (2011). Acta Cryst. E67, o961.]); Abe & Sasanuma (2012[Abe, D. & Sasanuma, Y. (2012). Polym. Chem. 3, 1576-1587.], 2013[Abe, D. & Sasanuma, Y. (2013). Acta Cryst. E69, o1612.]). For the synthesis, see: Jacobson et al. (1987[Jacobson, A. R., Makris, A. N. & Sayre, L. M. (1987). J. Org. Chem. 52, 2592-2594.]).

[Scheme 1]

Experimental

Crystal data
  • C16H16N2S2

  • Mr = 300.43

  • Triclinic, [P \overline 1]

  • a = 8.6652 (1) Å

  • b = 9.4596 (1) Å

  • c = 10.3457 (1) Å

  • α = 105.5452 (7)°

  • β = 98.9293 (7)°

  • γ = 101.5370 (6)°

  • V = 780.67 (2) Å3

  • Z = 2

  • Cu Kα radiation

  • μ = 3.01 mm−1

  • T = 223 K

  • 0.20 × 0.05 × 0.05 mm

Data collection
  • Bruker APEXII Ultra CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2001[Bruker (2001). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.58, Tmax = 0.86

  • 10280 measured reflections

  • 2763 independent reflections

  • 2568 reflections with I > 2σ(I)

  • Rint = 0.014

Refinement
  • R[F2 > 2σ(F2)] = 0.029

  • wR(F2) = 0.083

  • S = 1.04

  • 2763 reflections

  • 181 parameters

  • H-atom parameters constrained

  • Δρmax = 0.28 e Å−3

  • Δρmin = −0.18 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C2–C7 and C11–C16 phenyl rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯S2i 0.87 2.56 3.4186 (13) 168
N2—H2⋯S1ii 0.87 2.58 3.4097 (13) 159
C8—H8ACg2i 0.99 2.78 3.5376 (17) 134
C9—H9ACg1i 0.99 2.87 3.6685 (17) 140
Symmetry codes: (i) -x+1, -y+1, -z+2; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL2013.

Supporting information


Comment top

In our previous studies, conformational characteristics and configurational properties of aromatic polythioesters (X = O and Y = S) and polydithioesters (X = Y = S) (Abe & Sasanuma, 2012) expressed as [–(C=X)–C6H4–(C=X)–Y–(CH2)m–Y–]n were investigated through molecular orbital (MO) calculations and NMR and single-crystal X-ray diffraction experiments on their model compounds (Abe et al., 2011; Abe & Sasanuma, 2013). The theoretical and experimental data thus obtained were applied to the ab initio statistical mechanics to derive bond conformations, configurational properties, and thermodynamic quantities on the target polymers. In the present study, we have treated aromatic polyamides (X = O and Y = NH), polythioamides (X = S and Y = NH), and their model compounds, C6H5–(C=X)–NH–(CH2)m–NH–(C=X)–C6H5. Crystal structures of the model compounds (X = O and m = 2 and 3) of poly(ethylene terephthalamide) and poly(trimethylene terephthalamide) were already determined (Palmer & Brisse, 1980; Brisson & Brisse, 1986). This paper reports the crystal structure of N,N'-(ethane-1,2-diyl)benzenecarbothioamide (X = S and m = 2, referred to hereafter as EDBTA) corresponding to the model compound of poly(ethylene terephthalthioamide).

Figure 1 shows the molecular structure of EDBTA, whose NH–CH2–CH2–NH bonds adopt the g+g+g+ conformation. The MO calculations at the B3LYP/6–311+G(2d,p)//B3LYP/6–311+G(2d,p) level including the solvent effect of dimethyl sulfoxide have predicted conformational preferences of EDBTA; the first and second most stable conformers are tg+g (–0.99) and g+g+g+ (–0.76), respectively, where the values in the parentheses are Gibbs free energies in kcal mol–1 relative to that of the all-trans state.

According to the MO calculations, the tg+g conformer of EDBTA seems to form intramolecular C=S···H–N and C=S···C–H attractions. As shown in Figure 2, the crystallized EDBTA molecule, lying in the g+g+g+ conformation, forms intermolecular C=S···H–N and C–H..π interactions. Probably, the crystalline EDBTA chooses the intermolecular C=S···H–N interaction rather than the intramolecular one to acquire a larger energy stability. The MO calculations predicted that stable conformers of N,N'-(ethane-1,2-diyl)dibenzamide (X = O and m =2, abbreviated as EDBA), the model compound of poly(ethylene terephthalamide), are, in the ascending order of free energy, tg+g, g+tg+, g+g+g+, g+tg,···; the energy difference between g+tg and tg+g was estimated as 0.89 kcal mol-1. Nevertheless, the EDBA molecule crystallizes to adopt the fourth stable conformation, g+tg (Palmer & Brisse, 1980). In contrast with models of the polythioester (X = O, Y = S, and m = 2) and polydithioester (X = Y = S and m = 2) (Abe et al., 2011; Abe & Sasanuma, 2012), EDBA and EDBTA do not crystallize in the most stable conformation suggested by the MO calculations probably because of the significant stabilization of the intermolecular C=O···H—N and C=S···H—N hydrogen bonds.

Related literature top

For crystal structures and conformations of related compounds with –(C X)–C6H4–(CX)–Y–(CH2)mY– (X = O or S and Y = O, S, or NH) bond sequences, see for example,: Palmer & Brisse (1980); Brisson & Brisse (1986); Abe et al. (2011); Abe & Sasanuma (2012, 2013). For the synthesis, see: Jacobson et al. (1987).

Experimental top

Benzoyl chloride (4.6 ml, 40 mmol), dissolved in 1,2-dichloroethane (100 ml), was added dropwise to ethylenediamine (14 ml, 210 mmol) and 1,2-dichloroethane (300 ml) stirred by a magnetic stirrer in a three-necked flask equipped with a dropping funnel and a calcium-chloride drying tube, with the flask being bathed in ice water. The mixture was stirred at room temperature for 8 h to yield white precipitate. The precipitate was collected by suction filtration, washed with water, and dried. The crude product was recrystallized from methanol and dried at 40 °C under reduced pressure to yield EDBA (yield 55%). In principle, this synthesis is based on the procedure of Jacobson et al. (1987).

Lawesson's reagent (1.8 g, 4.6 mmol) and EDBA (1.0 g, 3.7 mmol) were dissolved in toluene (20 ml) stirred in a three-necked flask equipped with a reflux condenser connected to a calcium-chloride drying tube. The solution was refluxed under dry nitrogen at ca 110 °C for 8 h to yield yellow precipitate. The precipitate was collected, washed with toluene, recrystallized from ethanol, and dried at 40 °C under reduced pressure to yield EDBTA (yield 79%).

A small quantity of EDBTA was dissolved in chloroform in a glass tube, whose top was sealed with a thin Teflon film. The tube was placed in a vial container including a small amount of n-hexane, and the container was capped and left to stand still in a dark place. After a day, its crystals were found to be formed in the inner tube.

Refinement top

All H atoms were geometrically positioned with C—H = 0.95 and 0.99 Å for the aromatic and methylene groups, respectively, and N—H = 0.87 Å, and refined as riding by Uiso(H) = 1.2Ueq(C, N).

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 50% probability level. Isotropic H-atom thermal parameters are represented by spheres of arbitrary size. The labels of hydrogen atoms are omitted for clarity.
[Figure 2] Fig. 2. Packing diagrams of the title compound, viewed down the (a) a and (b) b axes. The dotted lines represent C=S···H—N and C—H···π interactions.
N,N'-(Ethane-1,2-diyl)dibenzenecarbothioamide top
Crystal data top
C16H16N2S2V = 780.67 (2) Å3
Mr = 300.43Z = 2
Triclinic, P1F(000) = 316
a = 8.6652 (1) ÅDx = 1.278 Mg m3
b = 9.4596 (1) ÅCu Kα radiation, λ = 1.54178 Å
c = 10.3457 (1) ŵ = 3.01 mm1
α = 105.5452 (7)°T = 223 K
β = 98.9293 (7)°Needle, yellow
γ = 101.5370 (6)°0.20 × 0.05 × 0.05 mm
Data collection top
Bruker APEXII Ultra CCD area-detector
diffractometer
2763 independent reflections
Radiation source: Bruker TXS fine-focus rotating anode2568 reflections with I > 2σ(I)
Bruker Helios multilayer mirror monochromatorRint = 0.014
ϕ and ω scansθmax = 68.2°, θmin = 4.6°
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
h = 1010
Tmin = 0.58, Tmax = 0.86k = 1111
10280 measured reflectionsl = 1012
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.083 w = 1/[σ2(Fo2) + (0.0481P)2 + 0.2337P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max = 0.001
2763 reflectionsΔρmax = 0.28 e Å3
181 parametersΔρmin = 0.18 e Å3
Crystal data top
C16H16N2S2γ = 101.5370 (6)°
Mr = 300.43V = 780.67 (2) Å3
Triclinic, P1Z = 2
a = 8.6652 (1) ÅCu Kα radiation
b = 9.4596 (1) ŵ = 3.01 mm1
c = 10.3457 (1) ÅT = 223 K
α = 105.5452 (7)°0.20 × 0.05 × 0.05 mm
β = 98.9293 (7)°
Data collection top
Bruker APEXII Ultra CCD area-detector
diffractometer
2763 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2001)
2568 reflections with I > 2σ(I)
Tmin = 0.58, Tmax = 0.86Rint = 0.014
10280 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0290 restraints
wR(F2) = 0.083H-atom parameters constrained
S = 1.04Δρmax = 0.28 e Å3
2763 reflectionsΔρmin = 0.18 e Å3
181 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 was performed with all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2, while the R-factor on F. The threshold expression of F2 > 2.0 σ(F2) was used only for calculating R-factor.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.55284 (15)0.70259 (14)0.66245 (14)0.0269 (3)
C20.39798 (16)0.74362 (15)0.62755 (14)0.0267 (3)
C30.25373 (17)0.65794 (16)0.63997 (14)0.0306 (3)
H30.25430.57620.67520.037*
C40.10937 (17)0.69267 (17)0.60064 (16)0.0356 (3)
H40.01210.63410.60860.043*
C50.10820 (18)0.81363 (18)0.54961 (16)0.0373 (3)
H50.01010.83690.52260.045*
C60.25101 (18)0.90021 (18)0.53830 (17)0.0379 (3)
H60.25010.98290.50440.046*
C70.39529 (17)0.86538 (16)0.57682 (15)0.0325 (3)
H70.49220.92440.56870.039*
C80.71343 (18)0.60757 (18)0.82305 (15)0.0353 (3)
H8A0.72370.61940.92130.042*
H8B0.81190.67070.81210.042*
C90.69808 (19)0.44220 (18)0.74548 (16)0.0374 (3)
H9A0.70120.43250.64930.045*
H9B0.79030.41040.78550.045*
C100.52445 (19)0.29310 (17)0.85582 (15)0.0360 (3)
C110.35708 (19)0.20806 (17)0.84557 (15)0.0363 (3)
C120.2252 (2)0.25356 (18)0.79138 (16)0.0400 (4)
H120.24170.33540.75560.048*
C130.0696 (2)0.1792 (2)0.78978 (18)0.0504 (4)
H130.01870.21210.75480.06*
C140.0438 (2)0.0564 (2)0.8396 (2)0.0569 (5)
H140.06180.00580.83830.068*
C150.1734 (3)0.0089 (2)0.89112 (19)0.0553 (5)
H150.15590.07560.92350.066*
C160.3285 (2)0.08408 (19)0.89556 (17)0.0453 (4)
H160.41620.05170.93260.054*
N10.57488 (14)0.66031 (14)0.77434 (12)0.0312 (3)
H10.50120.66420.82260.037*
N20.54942 (16)0.34276 (14)0.75044 (12)0.0361 (3)
H20.47020.31330.67850.043*
S10.68758 (4)0.70858 (4)0.56244 (4)0.03447 (12)
S20.67017 (5)0.32702 (6)0.99595 (4)0.04788 (14)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0259 (6)0.0285 (6)0.0259 (7)0.0067 (5)0.0055 (5)0.0083 (5)
C20.0270 (6)0.0306 (6)0.0236 (7)0.0092 (5)0.0072 (5)0.0080 (5)
C30.0319 (7)0.0325 (7)0.0311 (8)0.0095 (6)0.0100 (6)0.0130 (6)
C40.0262 (7)0.0414 (8)0.0396 (9)0.0069 (6)0.0104 (6)0.0125 (6)
C50.0299 (7)0.0492 (9)0.0379 (9)0.0186 (6)0.0074 (6)0.0154 (7)
C60.0407 (8)0.0415 (8)0.0422 (9)0.0190 (7)0.0127 (7)0.0220 (7)
C70.0303 (7)0.0356 (7)0.0366 (8)0.0092 (6)0.0116 (6)0.0164 (6)
C80.0350 (7)0.0483 (8)0.0265 (8)0.0169 (6)0.0040 (6)0.0146 (6)
C90.0429 (8)0.0509 (9)0.0288 (8)0.0240 (7)0.0129 (6)0.0176 (6)
C100.0488 (9)0.0408 (8)0.0268 (8)0.0243 (7)0.0112 (6)0.0129 (6)
C110.0507 (9)0.0385 (8)0.0238 (8)0.0186 (7)0.0097 (6)0.0102 (6)
C120.0493 (9)0.0439 (8)0.0310 (8)0.0175 (7)0.0090 (7)0.0142 (6)
C130.0482 (10)0.0628 (11)0.0392 (10)0.0172 (8)0.0077 (7)0.0128 (8)
C140.0600 (11)0.0595 (11)0.0434 (11)0.0015 (9)0.0154 (8)0.0110 (8)
C150.0809 (14)0.0453 (9)0.0417 (10)0.0100 (9)0.0196 (9)0.0175 (8)
C160.0657 (11)0.0440 (9)0.0324 (9)0.0218 (8)0.0114 (7)0.0158 (7)
N10.0325 (6)0.0418 (6)0.0256 (6)0.0160 (5)0.0096 (5)0.0140 (5)
N20.0444 (7)0.0439 (7)0.0251 (6)0.0188 (6)0.0073 (5)0.0138 (5)
S10.02655 (19)0.0504 (2)0.0359 (2)0.01414 (15)0.01281 (14)0.02216 (16)
S20.0469 (2)0.0748 (3)0.0317 (2)0.0247 (2)0.00711 (17)0.0264 (2)
Geometric parameters (Å, º) top
C1—N11.3216 (17)C9—H9A0.98
C1—C21.4882 (18)C9—H9B0.98
C1—S11.6783 (13)C10—N21.3278 (19)
C2—C71.3906 (19)C10—C111.484 (2)
C2—C31.3915 (19)C10—S21.6791 (15)
C3—C41.384 (2)C11—C121.390 (2)
C3—H30.94C11—C161.397 (2)
C4—C51.384 (2)C12—C131.386 (2)
C4—H40.94C12—H120.94
C5—C61.381 (2)C13—C141.385 (3)
C5—H50.94C13—H130.94
C6—C71.382 (2)C14—C151.376 (3)
C6—H60.94C14—H140.94
C7—H70.94C15—C161.377 (3)
C8—N11.4598 (17)C15—H150.94
C8—C91.523 (2)C16—H160.94
C8—H8A0.98N1—H10.87
C8—H8B0.98N2—H20.87
C9—N21.452 (2)
N1—C1—C2115.89 (11)N2—C9—H9B109.2
N1—C1—S1123.18 (10)C8—C9—H9B109.2
C2—C1—S1120.93 (10)H9A—C9—H9B107.9
C7—C2—C3119.15 (12)N2—C10—C11116.16 (13)
C7—C2—C1119.98 (12)N2—C10—S2122.96 (13)
C3—C2—C1120.82 (12)C11—C10—S2120.86 (11)
C4—C3—C2120.26 (13)C12—C11—C16118.40 (16)
C4—C3—H3119.9C12—C11—C10120.86 (13)
C2—C3—H3119.9C16—C11—C10120.69 (14)
C5—C4—C3120.02 (13)C13—C12—C11120.52 (15)
C5—C4—H4120.0C13—C12—H12119.7
C3—C4—H4120.0C11—C12—H12119.7
C6—C5—C4120.08 (13)C14—C13—C12120.19 (17)
C6—C5—H5120.0C14—C13—H13119.9
C4—C5—H5120.0C12—C13—H13119.9
C5—C6—C7120.05 (13)C15—C14—C13119.69 (18)
C5—C6—H6120.0C15—C14—H14120.2
C7—C6—H6120.0C13—C14—H14120.2
C6—C7—C2120.42 (13)C14—C15—C16120.44 (17)
C6—C7—H7119.8C14—C15—H15119.8
C2—C7—H7119.8C16—C15—H15119.8
N1—C8—C9112.27 (12)C15—C16—C11120.74 (16)
N1—C8—H8A109.1C15—C16—H16119.6
C9—C8—H8A109.1C11—C16—H16119.6
N1—C8—H8B109.1C1—N1—C8124.96 (12)
C9—C8—H8B109.1C1—N1—H1117.5
H8A—C8—H8B107.9C8—N1—H1117.5
N2—C9—C8112.14 (12)C10—N2—C9125.36 (13)
N2—C9—H9A109.2C10—N2—H2117.3
C8—C9—H9A109.2C9—N2—H2117.3
N1—C1—C2—C7140.90 (14)S2—C10—C11—C1638.65 (19)
S1—C1—C2—C739.89 (17)C16—C11—C12—C131.3 (2)
N1—C1—C2—C341.60 (18)C10—C11—C12—C13176.08 (15)
S1—C1—C2—C3137.61 (12)C11—C12—C13—C141.4 (3)
C7—C2—C3—C40.8 (2)C12—C13—C14—C150.2 (3)
C1—C2—C3—C4176.74 (13)C13—C14—C15—C161.1 (3)
C2—C3—C4—C50.4 (2)C14—C15—C16—C111.2 (3)
C3—C4—C5—C60.2 (2)C12—C11—C16—C150.0 (2)
C4—C5—C6—C70.6 (2)C10—C11—C16—C15177.37 (15)
C5—C6—C7—C20.2 (2)C2—C1—N1—C8176.47 (13)
C3—C2—C7—C60.5 (2)S1—C1—N1—C82.7 (2)
C1—C2—C7—C6177.09 (13)C9—C8—N1—C179.82 (18)
N1—C8—C9—N255.40 (17)C11—C10—N2—C9172.70 (13)
N2—C10—C11—C1239.7 (2)S2—C10—N2—C95.6 (2)
S2—C10—C11—C12138.62 (13)C8—C9—N2—C1079.40 (17)
N2—C10—C11—C16143.00 (15)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C2–C7 and C11–C16 phenyl rings, respectively.
D—H···AD—HH···AD···AD—H···A
N1—H1···S2i0.872.563.4186 (13)168
N2—H2···S1ii0.872.583.4097 (13)159
C8—H8A···Cg2i0.992.783.5376 (17)134
C9—H9A···Cg1i0.992.873.6685 (17)140
Symmetry codes: (i) x+1, y+1, z+2; (ii) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C2–C7 and C11–C16 phenyl rings, respectively.
D—H···AD—HH···AD···AD—H···A
N1—H1···S2i0.872.563.4186 (13)168
N2—H2···S1ii0.872.583.4097 (13)159
C8—H8A···Cg2i0.992.783.5376 (17)134
C9—H9A···Cg1i0.992.873.6685 (17)140
Symmetry codes: (i) x+1, y+1, z+2; (ii) x+1, y+1, z+1.
 

References

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