cis-Bis[1,1-dibenzyl-3-(furan-2-yl­carbonyl)thio­ureato-κ2 O,S]copper(II)

Hiram Pérez; Cecilia C P da Silva; Ana M Plutín; Carlos A de Simone; Javier Ellena

doi:10.1107/S160053681101422X

. 2011 Apr 22;67(Pt 5):m621. doi: 10.1107/S160053681101422X

cis-Bis[1,1-dibenzyl-3-(furan-2-ylcarbonyl)thioureato-κ² O,S]copper(II)

Hiram Pérez ^a,^*, Cecilia C P da Silva ^b, Ana M Plutín ^c, Carlos A de Simone ^b, Javier Ellena ^b

PMCID: PMC3089162 PMID: 21754333

Abstract

In the title compound, [Cu(C₂₀H₁₇N₂O₂S)₂], the Cu^II atom is coordinated by the S and O atoms of two 1,1-dibenzyl-3-(furan-2-ylcarbonyl)thioureate ligands in a distorted square-planar geometry. The two O and two S atoms are mutually cis to each other. The Cu—S and Cu—O bond lengths lie within the ranges of those found in related structures. The dihedral angle between the planes of the two chelating rings is 26.15 (6)°.

Related literature

For general background, see: Arslan et al. (2003 ▶). For synthesis details, see: Nagasawa & Mitsunobu (1981 ▶). For related structures, see: Binzet et al. (2006 ▶); Gomes et al. (2007 ▶); Pérez et al. (2011 ▶).

Experimental

Crystal data

[Cu(C₂₀H₁₇N₂O₂S)₂]
M _r = 762.37
Monoclinic,
a = 18.8390 (3) Å
b = 10.8730 (2) Å
c = 19.6200 (3) Å
β = 114.748 (1)°
V = 3649.79 (10) Å³
Z = 4
Mo Kα radiation
μ = 0.76 mm⁻¹
T = 293 K
0.49 × 0.44 × 0.39 mm

Data collection

Nonius KappaCCD area-detector diffractometer
Absorption correction: gaussian (Coppens et al., 1965 ▶) T _min = 0.779, T _max = 0.886
21982 measured reflections
7413 independent reflections
6761 reflections with I > 2σ(I)
R _int = 0.027

Refinement

R[F ² > 2σ(F ²)] = 0.049
wR(F ²) = 0.122
S = 1.07
7413 reflections
460 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.39 e Å⁻³

Data collection: COLLECT (Enraf–Nonius, 2000 ▶); cell refinement: SCALEPACK (Otwinowski & Minor, 1997 ▶); data reduction: DENZO (Otwinowski & Minor, 1997 ▶), SCALEPACK and SORTAV (Blessing, 1987 ▶, 1989 ▶); 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 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053681101422X/bt5517sup1.cif

e-67-0m621-sup1.cif^{(29.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S160053681101422X/bt5517Isup2.hkl

e-67-0m621-Isup2.hkl^{(355.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors thank the Grupo de Cristalografia, IFSC, USP, Brazil, for allowing the X-ray data collection. The authors acknowledge financial support from the PhD Cooperative Program ICTP/CLAF.

supplementary crystallographic information

Comment

N-acyl-N',N'-disubstituted thioureas have attracted the attention of researches over the last three decades with regard to coordination behaviour towards transition metals (Arslan et al., 2003). During complex formation, the ligand is deprotonated, which results in a neutral complex with a six-membered ring chelating the metal ion.

In the crystal structure of the title complex, the two furoylthiourea molecules adopt a cis conformation, bonded to the central Cu^II ion as shown in Fig. 1. The complex coordination geometry is a distorted square-plane as reflected by angles O1—Cu—S2 [166.02 (6)°] and O2—Cu—S1 [163.52 (7)°]. The distance of Cu atom from the best plane through the coordination sphere is 0.2486 (1) Å. The chelate ring systems, Cu–O1–C1–N1–C2–S1 and Cu–O2–C21–N3–C22–S2, are nearly planar with the largest deviations from the best plane being -0.118 (1) Å for C2 and 0.114 (2) Å for C22, respectively. The dihedral angle of 26.15 (6)° between these chelate planes indicates a strong distortion from square planar towards tetrahedral geometry. By comparison, the corresponding O—Ni—S angles and dihedral angle for the Ni^II analog (Pérez et al., 2011) are 169.66 (5)°, 170.09 (6)° and 20.33 (6)°, respectively. As a result, the square-planar coordination geometry of the title molecule is more distorted. The Cu—S and Cu—O bond lengths lie within the range of those found in the related structures (Gomes et al., 2007, Binzet et al., 2006). The bond lengths of the thiocarbonyl and carbonyl bonds are longer than the average for C═S (1.68 Å) and C═O (1.20 Å) in thioureas, while the C—N bonds in the chelate rings are all shorter than the average for C—N single bond of about 1.48 Å. This indicates extensive electronic delocalization within the complex rings. Fig. 2 shows the arrangement of the complex molecules in the unit cell.

Experimental

The 1,1-dibenzyl-3-[(furan-2-yl)-carbonyl]thiourea ligand was prepared using the standard procedure previously reported in the literature (Nagasawa & Mitsunobu, 1981) by the reaction of furoyl chloride with KSCN in anhydrous acetone, and then condensation with dibenzylamine. To an ethanol solution (30 ml) containing the ligand (0.70 g, 2 mmol) was added an ethanol solution of Cu(CH₃COO)₂.H₂O (0.20 g, 1 mmol). The solution was stirred at room temperature for 2 h, and at once a solution of NaOH (1 N) was added to adjust pH to the neutral value. The mixture was filtered and the filtrate was evaporated under reduced pressure to give a green solid, which was washed with acetone. Single crystals were obtained by slow evaporation of a chloroform/dichloromethane solution (1:1, v/v) of the complex.