research communications
N,N′-[(ethane-1,2-diyl)bis(azanediylcarbonothioyl)]bis(benzamide)
ofaDépartement de Chimie, UFR SATIC, Université Alioune Diop, Bambey, Senegal, bDépartement de Chimie, Faculté des Sciences et Techniques, Université Cheik Anta Diop, Dakar, Senegal, and cInstitut de Chimie des Substances Naturelles, CNRS UPR 2301, Université Paris-Sud, Université Paris-Saclay, 1 av. de la Terrasse, 91198 Gif-sur-Yvette, France
*Correspondence e-mail: i6thiam@yahoo.fr
The reaction of benzoyl chloride and ethylendiamine in the presence of potassium thiocyanate yielded a white solid, C18H18N4O2S2, which consists of two benzoylthioureido moieties connected by an ethylene chain. The consists of one half of the molecule, the complete molecule being generated by crystallographic inversion symmetry. Both thiourea moieties are in a trans conformation. An intramolecular N—H⋯O hydrogen bond occurs. In the crystal, C—H⋯S and C—H⋯O hydrogen bonds link the molecules, forming layers parallel to the ac plane.
Keywords: crystal structure; thiourea; ethylenediamine; benzoylthioureido.
CCDC reference: 1909438
1. Chemical context
Thiourea derivatives have been successfully used in the extraction of some transition metals (i.e. CuII, NiII and CoII) from acidic media. Thiourea derivatives have also been shown to possess antibacterial, antifungal, antitubercular, antithyroid and insecticidal properties (Arslan et al., 2004; Cunha et al., 2007). The structures of several types of thiourea derivatives and its metal complexes have been determined in recent decades. These compounds possess two arms which can act as a tetradentate ligand coordinating through the S atom and the benzoyl O atom of each arm. Urea and thiourea derivatives can behave as catalysts through double interaction by hydrogen bonding with the substrate (Sigman & Jacobsen, 1998; Cortes-Clerget et al., 2016). Thiourea derivatives with alkyl bridges can adopt diverse conformations (Thiam et al., 2008; Pansuriya et al., 2011). We have recently begun to examine the coordination behaviour of a series of substituted benzoylthiourea derivatives that possess a number of interesting properties and reported a thioureido ligand in which the two thioureido moieties are bridged by a 1,2-phenylene ring (Thiam et al., 2008). In this paper, we report the synthesis and the characterization of a molecule where the two thioureidos are bridged by an ethane-1,2-diyl group.
2. Structural commentary
The ; symmetry code: (a) −x + 2, −y + 1, −z + 1]. The benzoyl groups of each thiourea subunit are trans with respect to the thiono S atoms across the respective C2—N2 bonds. The 1-benzoyl-3-ethylthiourea fragments adopt a cis conformation with respect to the thiono S atom across the respective C2—N1 bonds. The S1—C2 [1.6626 (15) Å] and O1—C3 [1.2209 (16) Å] distances indicate that these correspond to double bonds and are comparable to those observed for 1,2-bis(N-benzoylthioureido)benzene [1.6574 (18) Å for S—C and 1.222 (2) Å for O7—C16] (Thiam et al., 2008). The C—N bond lengths [1.3744 (17)–1.3971 (17) Å] are in the normal range observed for a single C—N bond. The thiourea fragments S1/N1/N2/C1/C2 are planar, with a maximum deviation from the least-squares plane of 0.015 (1) Å for the N1 atom. The dihedral angle between this plane and that of the benzene ring (r.m.s. deviation = 0.006 Å) is 26.97 (5)° versus ca 34° when the benzene ring is chlorinated (Abusaadiya et al., 2016). As regularly noticed with carbonylurea derivatives, the molecule also forms intramolecular N1—H1 hydrogen bonds between the carbonyl O and thioamide H atoms producing S(6) rings (N1—H1⋯O1, Table 1).
of the title compound is a half-molecule with the other half being generated by an inversion centre located at the mid-point of the C1—C1a bond [Fig. 13. Supramolecular features
In the crystal, the molecules, which feature an overall Z-form, have both halves roughly parallel to the ac plane, whereas the mid-point of the C1—C1a bond lies orthogonally parallel to the (100) plane. Molecular layers running almost parallel to the ac plane are formed by intermolecular C—H⋯O and C—H⋯S interactions (Table 1 and Fig. 2). These layers stack along the b direction. Despite the presence of phenyl rings, no π–π interactions are observed in the crystal packing. However, the carbonyl function C3=O1 stacks on phenyl group C4–C9 of a neighbouring layer [O1⋯Cg1iv = 3.5543 (14) Å; Cg1 is the centroid of ring C4–C9; symmetry code: (iv) −x + 1, y + , −z + ].
4. Database survey
Reflecting the interest in compounds similar to the title compound, no less than 35 associated structures are included in the Cambridge Structural Database (Version 5.38; Groom et al., 2016). The match APALEK (Abusaadiya et al., 2016) is the most similar structure to the title compound, the only difference being the substitution of the phenyl ring on the C3 position by a Cl atom. In both cases, the benzoyl functions of each thiourea subunit are trans with respect to the thiono S atom across the C—N bond. The 1-benzoyl-3-ethylthiourea fragment adopts a cis conformation with respect to the thiono S atom across the respective C—N bond. Six structures in which the spacer is different from the spacer in the symmetrical bis(thioureido) molecule studied here appear in the literature. The angles between the phenyl rings are: 63.1° for DAVHOZ (Aydın et al., 2012), 10.2° for EGUYAH (Sow et al., 2009), 35.4° for NEWJIL (Light, 2018), 0.0° for QIXQUK (Ding et al., 2008), 3.2° for TIFQAD (Oyeka et al., 2018) and 0.0° for XIQPAP (Dong et al., 2007). In addition, 23 structures which contain only one arm with a thioureido moiety similar to the studied molecules are reported, while the other arm consists of diverse moieties: CIGDAZ (Karipcin et al., 2013), DELMUD (Ngah et al., 2006), EYACIQ (Shutalev et al., 2004), GIHMIV (Haynes et al., 2014), GIHMOB (Haynes et al., 2014), IFUZOZ (Hassan et al., 2008a,b), NIQROV (Yamin & Malik, 2007), NIQROV01 (Nguyen & Abram, 2008), POFKIG (Ngah et al., 2014), QEWHUY (Rakhshani et al., 2018), RUGKOU (Hassan et al., 2009), SAFPAT (Wei, 2016), SITKUC (Yamin et al., 2008), TADSIB (Zhang et al., 2003), TADTEY (Yusof & Yamin, 2003), TIBLEW (Khawar Rauf et al., 2007). TIHJAW (Yusof et al., 2007), UNUBAH (Hassan et al., 2011), WOGTUI (Hassan et al., 2008a,b), XEBQOM (Adan et al., 2012), YICDEU (Othman et al., 2007), YUPYEO (Zheng et al., 2010) and YUPYEO01 (Khan et al., 2018).
5. Synthesis and crystallization
All purchased chemicals and solvents were of reagent grade and were used without further purification. Melting points were determined with a Büchi 570 melting-point apparatus and were uncorrected. To a mixture of 7.02 g (72 mmol) of potassium thiocyanate and 100 ml of acetone was added dropwise a solution of 10.116 g (72 mmol) of benzoyl chloride in 50 ml of acetone. The resulting mixture was stirred under reflux for 1 h and cooled to room temperature. A solution of 2.2 g (36.6 mmol) of 1,2-ethylenediamine in 20 ml of acetone was added. The yellow solution obtained was stirred at room temperature during 2 h. Hydrochloric acid (0.1 N, 300 ml) was added and a white solid appeared after a few minutes. The compound was filtered off, washed with 3 × 50 ml of water and dried under vacuum. The solid product was washed with water and purified by recrystallization from an ethanol/dichloromethane mixture (1:1 v/v). 12.3 g of the title compound were obtained (yield 88.5%). A small quantity of powder was recrystallized from 5 ml of DMF. Colourless single crystals suitable to XRD grew within six days.
6. Refinement
Crystal data, data collection and structure . Aromatic H atoms were first located by HFIX and other H atoms were located in the difference Fourier map, positioned geometrically and allowed to ride on their respective parent atoms, with C—H = 0.93 (CarH) or 0.97 Å (CH2). The NH H atoms were located in a difference Fourier map and freely refined.
details are summarized in Table 2Supporting information
CCDC reference: 1909438
https://doi.org/10.1107/S205698901900495X/vm2216sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S205698901900495X/vm2216Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S205698901900495X/vm2216Isup3.cml
Data collection: CrysAlis PRO (Rigaku OD, 2018); cell
CrysAlis PRO (Rigaku OD, 2018); data reduction: CrysAlis PRO (Rigaku OD, 2018); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018 (Sheldrick, 2015b); software used to prepare material for publication: SHELXL2018 (Sheldrick, 2015b).C18H18N4O2S2 | F(000) = 404 |
Mr = 386.48 | Dx = 1.441 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.2250 (6) Å | Cell parameters from 3377 reflections |
b = 7.2547 (5) Å | θ = 4.7–30.2° |
c = 11.1397 (6) Å | µ = 0.32 mm−1 |
β = 100.978 (5)° | T = 293 K |
V = 890.55 (9) Å3 | Prism, colourless |
Z = 2 | 0.36 × 0.14 × 0.11 mm |
XtaLAB AFC12 (RINC): Kappa single diffractometer | 2328 independent reflections |
Radiation source: micro-focus sealed X-ray tube, Rigaku (Mo)mm03 X-ray Source | 1942 reflections with I > 2σ(I) |
Rigaku MaxFlux mirror monochromator | Rint = 0.040 |
ω scans | θmax = 30.0°, θmin = 3.7° |
Absorption correction: multi-scan CrysAlis PRO (Rigaku OD, 2018) | h = −15→14 |
Tmin = 0.513, Tmax = 1.000 | k = −10→9 |
7264 measured reflections | l = −15→15 |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.042 | Hydrogen site location: mixed |
wR(F2) = 0.121 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0683P)2 + 0.1222P] where P = (Fo2 + 2Fc2)/3 |
2325 reflections | (Δ/σ)max < 0.001 |
124 parameters | Δρmax = 0.36 e Å−3 |
2 restraints | Δρmin = −0.31 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.85736 (10) | 0.61198 (19) | 0.41958 (11) | 0.0399 (3) | |
HN1 | 0.8022 (15) | 0.636 (3) | 0.4606 (15) | 0.048* | |
O1 | 0.62565 (9) | 0.65743 (17) | 0.43252 (9) | 0.0452 (3) | |
C1 | 0.98347 (12) | 0.5989 (2) | 0.48195 (13) | 0.0398 (3) | |
H1A | 0.996007 | 0.675814 | 0.554503 | 0.048* | |
H1AB | 1.035920 | 0.643780 | 0.428470 | 0.048* | |
S1 | 0.90847 (3) | 0.53047 (7) | 0.20190 (4) | 0.05100 (17) | |
N2 | 0.69512 (10) | 0.59494 (18) | 0.25797 (10) | 0.0372 (3) | |
HN2 | 0.6711 (17) | 0.573 (2) | 0.1826 (14) | 0.045* | |
C2 | 0.82013 (12) | 0.58234 (19) | 0.30120 (12) | 0.0351 (3) | |
C3 | 0.60474 (11) | 0.62787 (19) | 0.32261 (12) | 0.0332 (3) | |
C4 | 0.47845 (11) | 0.61990 (18) | 0.25055 (12) | 0.0323 (3) | |
C5 | 0.44876 (13) | 0.6519 (2) | 0.12543 (12) | 0.0380 (3) | |
H5 | 0.508903 | 0.681492 | 0.081672 | 0.046* | |
C6 | 0.32849 (14) | 0.6391 (2) | 0.06642 (14) | 0.0446 (3) | |
H6 | 0.308060 | 0.662390 | −0.017073 | 0.054* | |
C7 | 0.23884 (13) | 0.5923 (2) | 0.13013 (16) | 0.0466 (4) | |
H7 | 0.158787 | 0.581443 | 0.089304 | 0.056* | |
C8 | 0.26809 (14) | 0.5617 (2) | 0.25436 (16) | 0.0469 (4) | |
H8 | 0.207621 | 0.530909 | 0.297439 | 0.056* | |
C9 | 0.38722 (13) | 0.5766 (2) | 0.31507 (13) | 0.0396 (3) | |
H9 | 0.406519 | 0.557780 | 0.399116 | 0.048* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0294 (6) | 0.0525 (7) | 0.0365 (6) | 0.0051 (5) | 0.0025 (4) | −0.0034 (5) |
O1 | 0.0362 (5) | 0.0667 (7) | 0.0327 (5) | 0.0038 (5) | 0.0061 (4) | −0.0008 (5) |
C1 | 0.0288 (6) | 0.0468 (8) | 0.0405 (7) | −0.0030 (5) | −0.0013 (5) | −0.0052 (6) |
S1 | 0.0316 (2) | 0.0798 (3) | 0.0436 (2) | −0.00179 (16) | 0.01212 (16) | −0.00785 (18) |
N2 | 0.0274 (5) | 0.0518 (7) | 0.0316 (5) | 0.0025 (5) | 0.0039 (4) | −0.0014 (5) |
C2 | 0.0282 (6) | 0.0395 (7) | 0.0371 (6) | −0.0016 (5) | 0.0049 (5) | 0.0012 (5) |
C3 | 0.0291 (6) | 0.0373 (7) | 0.0333 (6) | 0.0012 (5) | 0.0063 (5) | 0.0036 (5) |
C4 | 0.0283 (6) | 0.0338 (6) | 0.0347 (6) | 0.0024 (5) | 0.0058 (5) | 0.0027 (5) |
C5 | 0.0348 (6) | 0.0427 (7) | 0.0362 (6) | −0.0003 (5) | 0.0063 (5) | 0.0053 (5) |
C6 | 0.0410 (7) | 0.0497 (8) | 0.0390 (7) | 0.0026 (6) | −0.0030 (6) | 0.0041 (6) |
C7 | 0.0285 (6) | 0.0490 (9) | 0.0586 (9) | 0.0040 (6) | −0.0009 (6) | 0.0005 (7) |
C8 | 0.0313 (7) | 0.0552 (9) | 0.0571 (9) | 0.0028 (6) | 0.0155 (6) | 0.0040 (7) |
C9 | 0.0331 (7) | 0.0486 (8) | 0.0387 (7) | 0.0034 (6) | 0.0108 (5) | 0.0048 (6) |
N1—C2 | 1.3228 (17) | C4—C5 | 1.3894 (17) |
N1—C1 | 1.4564 (17) | C4—C9 | 1.3944 (18) |
N1—HN1 | 0.854 (14) | C5—C6 | 1.388 (2) |
O1—C3 | 1.2209 (16) | C5—H5 | 0.9300 |
C1—C1i | 1.518 (3) | C6—C7 | 1.380 (2) |
C1—H1A | 0.9700 | C6—H6 | 0.9300 |
C1—H1AB | 0.9700 | C7—C8 | 1.378 (2) |
S1—C2 | 1.6633 (14) | C7—H7 | 0.9300 |
N2—C3 | 1.3723 (17) | C8—C9 | 1.383 (2) |
N2—C2 | 1.3971 (16) | C8—H8 | 0.9300 |
N2—HN2 | 0.846 (14) | C9—H9 | 0.9300 |
C3—C4 | 1.4913 (17) | ||
C2—N1—C1 | 123.98 (12) | C5—C4—C9 | 119.69 (12) |
C2—N1—HN1 | 116.3 (12) | C5—C4—C3 | 123.74 (12) |
C1—N1—HN1 | 119.7 (12) | C9—C4—C3 | 116.58 (12) |
N1—C1—C1i | 110.75 (14) | C6—C5—C4 | 119.34 (13) |
N1—C1—H1A | 109.5 | C6—C5—H5 | 120.3 |
C1i—C1—H1A | 109.5 | C4—C5—H5 | 120.3 |
N1—C1—H1AB | 109.5 | C7—C6—C5 | 120.78 (14) |
C1i—C1—H1AB | 109.5 | C7—C6—H6 | 119.6 |
H1A—C1—H1AB | 108.1 | C5—C6—H6 | 119.6 |
C3—N2—C2 | 128.67 (11) | C8—C7—C6 | 119.91 (13) |
C3—N2—HN2 | 115.1 (13) | C8—C7—H7 | 120.0 |
C2—N2—HN2 | 116.1 (13) | C6—C7—H7 | 120.0 |
N1—C2—N2 | 116.03 (12) | C7—C8—C9 | 120.11 (14) |
N1—C2—S1 | 125.77 (10) | C7—C8—H8 | 119.9 |
N2—C2—S1 | 118.19 (10) | C9—C8—H8 | 119.9 |
O1—C3—N2 | 122.46 (12) | C8—C9—C4 | 120.15 (14) |
O1—C3—C4 | 121.88 (12) | C8—C9—H9 | 119.9 |
N2—C3—C4 | 115.64 (11) | C4—C9—H9 | 119.9 |
C2—N1—C1—C1i | −84.6 (2) | N2—C3—C4—C9 | 154.33 (13) |
C1—N1—C2—N2 | 177.90 (13) | C9—C4—C5—C6 | −0.4 (2) |
C1—N1—C2—S1 | −1.5 (2) | C3—C4—C5—C6 | 179.28 (13) |
C3—N2—C2—N1 | −2.5 (2) | C4—C5—C6—C7 | −1.1 (2) |
C3—N2—C2—S1 | 177.01 (12) | C5—C6—C7—C8 | 1.5 (3) |
C2—N2—C3—O1 | 2.4 (2) | C6—C7—C8—C9 | −0.4 (3) |
C2—N2—C3—C4 | −175.85 (13) | C7—C8—C9—C4 | −1.0 (2) |
O1—C3—C4—C5 | 156.36 (14) | C5—C4—C9—C8 | 1.4 (2) |
N2—C3—C4—C5 | −25.33 (19) | C3—C4—C9—C8 | −178.28 (14) |
O1—C3—C4—C9 | −23.98 (19) |
Symmetry code: (i) −x+2, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—HN1···O1 | 0.86 (2) | 1.95 (2) | 2.6528 (16) | 138 (2) |
C5—H5···O1ii | 0.93 | 2.58 | 3.478 (16) | 162 |
C9—H9···O1iii | 0.93 | 2.52 | 3.311 (16) | 143 |
C1—H1A···S1iv | 0.97 | 2.97 | 3.8375 (16) | 150 |
Symmetry codes: (ii) x, −y+3/2, z−1/2; (iii) −x+1, −y+1, −z+1; (iv) x, −y+3/2, z+1/2. |
Acknowledgements
The authors are grateful to the Sonatel Foundation for financial support.
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