1,3-Bis(2-meth­oxy­phen­yl)thio­urea

Rooyen, J. van; Betz, R.; Brecht, B.J.A.M. van

doi:10.1107/S1600536811040852

organic compounds

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ISSN: 2056-9890

Volume 67| Part 11| November 2011| Page o2889

doi:10.1107/S1600536811040852

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1,3-Bis(2-methoxyphenyl)thiourea

Jason van Rooyen,^a Richard Betz ^a ^* and Bernardus J. A. M. van Brecht ^a

^aNelson Mandela Metropolitan University, Summerstrand Campus, Department of Chemistry, University Way, Summerstrand, PO Box 77000, Port Elizabeth 6031, South Africa
^*Correspondence e-mail: richard.betz@webmail.co.za

(Received 28 September 2011; accepted 4 October 2011; online 8 October 2011)

In the title compound, C₁₅H₁₆N₂O₂S, the N–C(=S) bond lengths are indicative of the presence of amide-type resonance. The dihedral angles between the thiourea unit and the attached aromatic rings are 59.80 (5) and 73.41 (4)° while the dihedral angle between the rings is 56.83 (4)°. In the crystal, inversion dimers linked by pairs of N—H⋯S hydrogen bonds occur. An N—H⋯π interaction is observed for the second amino group. The shortest centroid–centroid distance between two aromatic systems is 4.0958 (8) Å.

Related literature

For related structures, see: Shashidhar et al. (2006 ); Muhammed et al. (2007 ); Kuan & Tiekink (2007 ); Srivastava et al. (2010 ). For further synthetic details, see: Voss & Walter (1968 ). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990 ); Bernstein et al. (1995 ). For general information about coordination chemistry, see: Gade (1998 ). Structures containing similar bond lengths were retrieved from the Cambridge Structural Database (Allen, 2002 ).

Experimental

Crystal data

C₁₅H₁₆N₂O₂S
M_r = 288.36
Monoclinic, C 2/c
a = 14.3187 (8) Å
b = 12.8628 (7) Å
c = 16.1168 (10) Å
β = 103.790 (3)°
V = 2882.8 (3) Å³
Z = 8
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 173 K
0.42 × 0.36 × 0.14 mm

Data collection

Bruker SMART CCD diffractometer
10474 measured reflections
3567 independent reflections
2765 reflections with I > 2σ(I)
R_int = 0.058

Refinement

R[F² > 2σ(F²)] = 0.033
wR(F²) = 0.090
S = 1.05
3567 reflections
191 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.25 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C11–C16 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H72⋯S1ⁱ	0.831 (16)	2.506 (17)	3.3343 (12)	174.3 (14)
N1—H71⋯Cg1ⁱⁱ	0.782 (16)	2.967 (18)	3.5127 (13)	129.1 (14)
Symmetry codes: (i) $[-x, y, -z+{\script{1\over 2}}]$ ; (ii) $[-x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z]$ .

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811040852/hb6427sup1.cif

Supporting information file. DOI: 10.1107/S1600536811040852/hb6427Isup2.cdx

Structure factors: contains datablock I. DOI: 10.1107/S1600536811040852/hb6427Isup3.hkl

Supporting information file. DOI: 10.1107/S1600536811040852/hb6427Isup4.cml

checkCIF report

Comment top

Chelate ligands have found widespread use in coordination chemistry due to the enhanced thermodynamic stability of resultant coordination compounds in relation to coordination compounds exclusively applying comparable monodentate ligands (Gade, 1998). Combining different donor atoms, a molecular set-up to accomodate a large variety of metal centers of variable Lewis acidity is at hand. In this aspect, the title compound, 1,3-bis(2-methoxyphenyl)thiourea, (I), seemed of interest due to its possible use as a strictly neutral or, depending on the pH value, as an anionic or cationic ligand. In addition, due to the set-up of its functional groups, it may act as mono- or multidentate ligand offering the possibility to create chelate rings of various size. The intriguing combination of a secondary amino group, a thioketo group as well as methylether groups classifies the title compound as a highly versatile ligand. To enable comparative studies in terms of bond lengths and angles in envisioned coordination compounds, we determined the molecular and crystal structure of the title compound. Information about the crystal structure of 1,3-bis(4-methoxyphenyl)thiourea (Shashidhar et al., 2006), 1,3-bis(2-methylphenyl)thiourea, (Muhammed et al., 2007; Kuan & Tiekink, 2007) and 1,3-bis(phenyl)thiourea (Srivastava et al., 2010) is available in the literature.

N–C=S bond lengths (d_N–C: 1.3469 (15) Å and 1.3488 (16) Å, respectively) are in good agreement with values deposited for comparable compounds with the Cambridge Structural Database (Allen, 2002) and are indicative of admide-type resonance between the atoms of this entity. This finding is further corroborated by the planarity of the S=CN₂ moiety (r.m.s. of all fitted atoms = 0.0015 Å). The aromatic substituents on the nitrogen atom adopt syn and anti conformation with respect to the sulfur atom. The least-squares planes defined by the carbon atoms of the respective phenyl rings enclose an angle of 56.83 (4) ° while the individual planes defined by the phenyl rings intersect with the least-squares plane defined by the atoms of the central S=CN₂ moiety at angles of 59.80 (5) ° and 73.41 (4) ° (Fig. 1, Fig. 2).

In the crystal, the hydrogen atoms of the secondary amine groups participate in two different types of intermolecular interactions. While one of the protons is part of a classical hydrogen bond of the N–H···S type, the other amine group's hydrogen atom forms a contact to one of the aromatic systems. The classical hydrogen bonds connect the molecules to centrosymmetric dimers orientated approximately perpendicular to the crystallographic b axis. In terms of graph-set analysis (Etter et al., 1990; Bernstein et al., 1995), the descriptor for the classical hydrogen bonds is R²₂(8) on the unitary level. The shortest intercentroid distance between two aromatic systems was measured at 4.0958 (8) Å (Fig. 3).

The packing of the title compound in the crystal structure is shown in Figure 4.

Related literature top

For related structures, see: Shashidhar et al. (2006); Muhammed et al. (2007); Kuan & Tiekink (2007); Srivastava et al. (2010). For further synthetic details, see: Voss & Walter (1968). For graph-set analysis of hydrogen bonds, see: Etter et al. (1990); Bernstein et al. (1995). For general information about coordination chemistry, see: Gade (1998). Structures containing similar bond lengths were retrieved from the Cambridge Structural Database (Allen, 2002).

Experimental top

The title compound was prepared upon reacting Lawesson's reagent with the corresponding amide in analogy to a published procedure (Voss & Walter, 1968).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, with anisotropic displacement ellipsoids (drawn at 50% probability level).
	Fig. 2. Statistical distribution of N(H)–C(=S) bond lengths in thiourea-derived amides (data based on CSD search including all deposited crystal structures up to August 2011).
	Fig. 3. Intermolecular contacts, viewed along [0 1 0]. Symmetry operator: ⁱ -x, y, -z + 1/2.
	Fig. 4. Molecular packing of the title compound, viewed along [0 1 0] (anisotropic displacement ellipsoids drawn at 50% probability level).

1,3-Bis(2-methoxyphenyl)thiourea top

Crystal data top

C₁₅H₁₆N₂O₂S	Z = 8
M_r = 288.36	F(000) = 1216
Monoclinic, C2/c	D_x = 1.329 Mg m⁻³
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 14.3187 (8) Å	µ = 0.23 mm⁻¹
b = 12.8628 (7) Å	T = 173 K
c = 16.1168 (10) Å	Plate, colourless
β = 103.790 (3)°	0.42 × 0.36 × 0.14 mm
V = 2882.8 (3) Å³

Data collection top

Bruker SMART CCD diffractometer	2765 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.058
Graphite monochromator	θ_max = 28.3°, θ_min = 2.2°
ϕ and ω scans	h = −16→19
10474 measured reflections	k = −14→17
3567 independent reflections	l = −17→21

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.090	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	w = 1/[σ²(F_o²) + (0.0437P)² + 0.1621P] where P = (F_o² + 2F_c²)/3
3567 reflections	(Δ/σ)_max < 0.001
191 parameters	Δρ_max = 0.25 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₅H₁₆N₂O₂S	V = 2882.8 (3) Å³
M_r = 288.36	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 14.3187 (8) Å	µ = 0.23 mm⁻¹
b = 12.8628 (7) Å	T = 173 K
c = 16.1168 (10) Å	0.42 × 0.36 × 0.14 mm
β = 103.790 (3)°

Data collection top

Bruker SMART CCD diffractometer	2765 reflections with I > 2σ(I)
10474 measured reflections	R_int = 0.058
3567 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.033	0 restraints
wR(F²) = 0.090	H atoms treated by a mixture of independent and constrained refinement
S = 1.05	Δρ_max = 0.25 e Å⁻³
3567 reflections	Δρ_min = −0.23 e Å⁻³
191 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
S1	−0.01726 (2)	0.20091 (3)	0.11713 (2)	0.02289 (10)
O1	0.09218 (7)	0.42621 (7)	−0.03050 (6)	0.0323 (2)
O2	0.24916 (6)	0.20317 (7)	0.36118 (6)	0.0291 (2)
N1	0.14650 (8)	0.28483 (9)	0.09695 (7)	0.0251 (3)
H71	0.1955 (12)	0.3130 (13)	0.1153 (10)	0.036 (5)*
N2	0.12052 (7)	0.29144 (9)	0.23257 (7)	0.0232 (2)
H72	0.0931 (11)	0.2653 (11)	0.2676 (10)	0.028 (4)*
C1	0.08967 (8)	0.26236 (9)	0.15016 (8)	0.0197 (3)
C11	0.12847 (8)	0.25261 (10)	0.00981 (8)	0.0223 (3)
C12	0.10350 (9)	0.32650 (10)	−0.05553 (8)	0.0238 (3)
C13	0.09201 (9)	0.29468 (11)	−0.14003 (9)	0.0288 (3)
H13	0.0771	0.3444	−0.1849	0.035*
C14	0.10227 (9)	0.19063 (12)	−0.15889 (9)	0.0307 (3)
H14	0.0929	0.1695	−0.2168	0.037*
C15	0.12589 (10)	0.11744 (11)	−0.09458 (9)	0.0311 (3)
H15	0.1324	0.0463	−0.1079	0.037*
C16	0.14008 (9)	0.14937 (11)	−0.00994 (9)	0.0281 (3)
H16	0.1579	0.0998	0.0347	0.034*
C17	0.06484 (12)	0.50262 (12)	−0.09648 (10)	0.0408 (4)
H171	0.1170	0.5116	−0.1257	0.061*
H172	0.0523	0.5689	−0.0712	0.061*
H173	0.0066	0.4796	−0.1377	0.061*
C21	0.20704 (8)	0.34620 (10)	0.26996 (8)	0.0215 (3)
C22	0.27304 (8)	0.30070 (10)	0.33908 (8)	0.0218 (3)
C23	0.35552 (9)	0.35490 (11)	0.37961 (8)	0.0257 (3)
H23	0.3997	0.3251	0.4272	0.031*
C24	0.37282 (9)	0.45274 (11)	0.35004 (9)	0.0287 (3)
H24	0.4298	0.4889	0.3770	0.034*
C25	0.30840 (10)	0.49852 (10)	0.28199 (9)	0.0299 (3)
H25	0.3210	0.5655	0.2623	0.036*
C26	0.22491 (9)	0.44499 (11)	0.24273 (9)	0.0267 (3)
H26	0.1797	0.4765	0.1968	0.032*
C27	0.31264 (10)	0.15497 (12)	0.43256 (10)	0.0358 (3)
H271	0.3761	0.1461	0.4205	0.054*
H272	0.2869	0.0869	0.4430	0.054*
H273	0.3185	0.1989	0.4832	0.054*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.01794 (15)	0.03006 (19)	0.02002 (17)	−0.00105 (12)	0.00324 (11)	−0.00245 (13)
O1	0.0424 (6)	0.0268 (5)	0.0263 (5)	0.0036 (4)	0.0056 (4)	0.0003 (4)
O2	0.0276 (5)	0.0279 (5)	0.0269 (5)	−0.0045 (4)	−0.0032 (4)	0.0055 (4)
N1	0.0220 (5)	0.0345 (7)	0.0186 (6)	−0.0060 (5)	0.0046 (4)	−0.0010 (5)
N2	0.0198 (5)	0.0333 (6)	0.0162 (5)	−0.0042 (4)	0.0035 (4)	0.0021 (5)
C1	0.0190 (5)	0.0199 (6)	0.0193 (6)	0.0044 (4)	0.0026 (5)	0.0035 (5)
C11	0.0195 (5)	0.0302 (7)	0.0183 (6)	−0.0015 (5)	0.0065 (5)	−0.0004 (6)
C12	0.0218 (6)	0.0275 (7)	0.0225 (7)	0.0000 (5)	0.0059 (5)	−0.0017 (5)
C13	0.0274 (6)	0.0381 (8)	0.0206 (7)	0.0024 (6)	0.0052 (5)	0.0017 (6)
C14	0.0256 (6)	0.0439 (9)	0.0233 (7)	−0.0013 (6)	0.0072 (5)	−0.0096 (6)
C15	0.0312 (7)	0.0299 (8)	0.0354 (8)	−0.0016 (5)	0.0144 (6)	−0.0063 (6)
C16	0.0277 (6)	0.0292 (7)	0.0296 (8)	−0.0007 (5)	0.0112 (5)	0.0018 (6)
C17	0.0526 (9)	0.0313 (8)	0.0366 (9)	0.0041 (7)	0.0067 (7)	0.0071 (7)
C21	0.0201 (5)	0.0267 (7)	0.0181 (6)	−0.0015 (5)	0.0056 (5)	−0.0035 (5)
C22	0.0225 (6)	0.0226 (6)	0.0205 (6)	−0.0003 (5)	0.0056 (5)	−0.0025 (5)
C23	0.0230 (6)	0.0308 (8)	0.0214 (7)	0.0010 (5)	0.0016 (5)	−0.0049 (6)
C24	0.0267 (6)	0.0289 (8)	0.0306 (8)	−0.0052 (5)	0.0074 (6)	−0.0120 (6)
C25	0.0367 (7)	0.0210 (7)	0.0342 (8)	−0.0026 (5)	0.0129 (6)	−0.0032 (6)
C26	0.0293 (6)	0.0263 (7)	0.0246 (7)	0.0035 (5)	0.0067 (5)	−0.0002 (6)
C27	0.0371 (7)	0.0326 (8)	0.0321 (8)	0.0016 (6)	−0.0027 (6)	0.0081 (7)

Geometric parameters (Å, º) top

S1—C1	1.6923 (12)	C15—H15	0.9500
O1—C12	1.3658 (16)	C16—H16	0.9500
O1—C17	1.4324 (17)	C17—H171	0.9800
O2—C22	1.3695 (15)	C17—H172	0.9800
O2—C27	1.4266 (16)	C17—H173	0.9800
N1—C1	1.3469 (15)	C21—C26	1.3879 (19)
N1—C11	1.4275 (16)	C21—C22	1.4053 (17)
N1—H71	0.782 (16)	C22—C23	1.3928 (17)
N2—C1	1.3488 (16)	C23—C24	1.3887 (19)
N2—C21	1.4277 (15)	C23—H23	0.9500
N2—H72	0.831 (16)	C24—C25	1.385 (2)
C11—C16	1.3848 (18)	C24—H24	0.9500
C11—C12	1.4003 (18)	C25—C26	1.3939 (19)
C12—C13	1.3937 (19)	C25—H25	0.9500
C13—C14	1.388 (2)	C26—H26	0.9500
C13—H13	0.9500	C27—H271	0.9800
C14—C15	1.381 (2)	C27—H272	0.9800
C14—H14	0.9500	C27—H273	0.9800
C15—C16	1.392 (2)

C12—O1—C17	117.11 (11)	O1—C17—H172	109.5
C22—O2—C27	117.21 (10)	H171—C17—H172	109.5
C1—N1—C11	124.69 (11)	O1—C17—H173	109.5
C1—N1—H71	118.9 (12)	H171—C17—H173	109.5
C11—N1—H71	116.2 (12)	H172—C17—H173	109.5
C1—N2—C21	126.87 (11)	C26—C21—C22	119.49 (11)
C1—N2—H72	117.3 (10)	C26—C21—N2	121.67 (11)
C21—N2—H72	114.6 (10)	C22—C21—N2	118.75 (11)
N1—C1—N2	117.50 (11)	O2—C22—C23	124.96 (12)
N1—C1—S1	122.59 (10)	O2—C22—C21	115.17 (11)
N2—C1—S1	119.91 (9)	C23—C22—C21	119.87 (12)
C16—C11—C12	120.07 (12)	C24—C23—C22	119.56 (12)
C16—C11—N1	120.07 (12)	C24—C23—H23	120.2
C12—C11—N1	119.79 (12)	C22—C23—H23	120.2
O1—C12—C13	124.73 (12)	C25—C24—C23	121.17 (12)
O1—C12—C11	116.24 (11)	C25—C24—H24	119.4
C13—C12—C11	119.02 (13)	C23—C24—H24	119.4
C14—C13—C12	120.20 (13)	C24—C25—C26	119.12 (13)
C14—C13—H13	119.9	C24—C25—H25	120.4
C12—C13—H13	119.9	C26—C25—H25	120.4
C15—C14—C13	120.84 (13)	C21—C26—C25	120.76 (13)
C15—C14—H14	119.6	C21—C26—H26	119.6
C13—C14—H14	119.6	C25—C26—H26	119.6
C14—C15—C16	119.12 (13)	O2—C27—H271	109.5
C14—C15—H15	120.4	O2—C27—H272	109.5
C16—C15—H15	120.4	H271—C27—H272	109.5
C11—C16—C15	120.70 (13)	O2—C27—H273	109.5
C11—C16—H16	119.6	H271—C27—H273	109.5
C15—C16—H16	119.6	H272—C27—H273	109.5
O1—C17—H171	109.5

C11—N1—C1—N2	174.85 (11)	N1—C11—C16—C15	−177.83 (11)
C11—N1—C1—S1	−5.62 (18)	C14—C15—C16—C11	1.57 (19)
C21—N2—C1—N1	1.47 (19)	C1—N2—C21—C26	60.94 (18)
C21—N2—C1—S1	−178.08 (10)	C1—N2—C21—C22	−122.51 (14)
C1—N1—C11—C16	−71.93 (16)	C27—O2—C22—C23	1.70 (18)
C1—N1—C11—C12	111.13 (14)	C27—O2—C22—C21	−178.28 (11)
C17—O1—C12—C13	1.17 (18)	C26—C21—C22—O2	−179.98 (11)
C17—O1—C12—C11	−178.84 (12)	N2—C21—C22—O2	3.39 (16)
C16—C11—C12—O1	179.11 (11)	C26—C21—C22—C23	0.04 (18)
N1—C11—C12—O1	−3.95 (16)	N2—C21—C22—C23	−176.59 (11)
C16—C11—C12—C13	−0.90 (17)	O2—C22—C23—C24	178.63 (11)
N1—C11—C12—C13	176.04 (11)	C21—C22—C23—C24	−1.39 (19)
O1—C12—C13—C14	−177.99 (12)	C22—C23—C24—C25	1.41 (19)
C11—C12—C13—C14	2.02 (18)	C23—C24—C25—C26	−0.1 (2)
C12—C13—C14—C15	−1.4 (2)	C22—C21—C26—C25	1.34 (19)
C13—C14—C15—C16	−0.4 (2)	N2—C21—C26—C25	177.86 (12)
C12—C11—C16—C15	−0.89 (18)	C24—C25—C26—C21	−1.3 (2)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C11–C16 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N2—H72···S1ⁱ	0.831 (16)	2.506 (17)	3.3343 (12)	174.3 (14)
N1—H71···Cg1ⁱⁱ	0.782 (16)	2.967 (18)	3.5127 (13)	129.1 (14)

Symmetry codes: (i) −x, y, −z+1/2; (ii) −x+1/2, −y+1/2, −z.

Experimental details

Crystal data
Chemical formula	C₁₅H₁₆N₂O₂S
M_r	288.36
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	173
a, b, c (Å)	14.3187 (8), 12.8628 (7), 16.1168 (10)
β (°)	103.790 (3)
V (Å³)	2882.8 (3)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.42 × 0.36 × 0.14

Data collection
Diffractometer	Bruker SMART CCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	10474, 3567, 2765
R_int	0.058
(sin θ/λ)_max (Å⁻¹)	0.666

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.090, 1.05
No. of reflections	3567
No. of parameters	191
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.25, −0.23

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C11–C16 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N2—H72···S1ⁱ	0.831 (16)	2.506 (17)	3.3343 (12)	174.3 (14)
N1—H71···Cg1ⁱⁱ	0.782 (16)	2.967 (18)	3.5127 (13)	129.1 (14)

Symmetry codes: (i) −x, y, −z+1/2; (ii) −x+1/2, −y+1/2, −z.

Acknowledgements

The authors thank Dr Marc van der Vyver for helpful discussions.

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Volume 67| Part 11| November 2011| Page o2889

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