Hexa­kis­(μ3-1-methyl­thio­urea-κ3S:S:S)hexa­kis­[iodidocopper(I)]

Ahmad, S.; Mufakkar, M.; Khan, I.U.; Fun, H.-K.; Waheed, A.

doi:10.1107/S1600536812043437

metal-organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Pages m1405-m1406

doi:10.1107/S1600536812043437

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Hexakis(μ₃-1-methylthiourea-κ³S:S:S)hexakis[iodidocopper(I)]

Saeed Ahmad,^a ^* Muhammad Mufakkar,^b Islam Ullah Khan,^c Hoong-Kun Fun ^d and Abdul Waheed ^c

^aDepartment of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan, ^bDepartment of Chemistry, Government College of Science, Wahdat Road, Lahore, Pakistan, ^cDepartment of Chemistry, Government College University, Lahore, Pakistan, and ^dX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: saeed_a786@hotmail.com

(Received 16 October 2012; accepted 18 October 2012; online 24 October 2012)

The title compound, [Cu₆I₆(C₂H₆N₂S)₆], was obtained from the reaction of copper(I) iodide with N-methylthiourea (Metu) in equimolar amounts in acetonitile. The complex consists of two six-membered trinuclear Cu₃S₃I₃ cores that combine through triply bridging Metu, forming a hexanuclear core which has -3 symmetry. The Cu^II atom is coordinated by three S atoms of Metu and one iodide ion in a distorted tetrahedral geometry. The crystal structure is stabilized by N—H⋯I hydrogen bonds and cuprophilic interactions [Cu⋯Cu = 3.0264 (9) Å].

Related literature

For crystal structures of copper(I) complexes of thiourea-type ligands, see: Ahmad et al. (2010 ); Bowmaker et al. (2009 ); Li et al. (2005 ); Lobana et al. (2003 , 2005 ); Khan et al. (2007 ); Mufakkar et al. (2007 , 2009 , 2011 ); Stocker et al. (1997 ); Zoufala et al. (2007 ). For van der Waals radii and cuprophilic interactions, see: Siemeling et al. (1997 ); Singh et al. (1997 ).

Experimental

Crystal data

[Cu₆I₆(C₂H₆N₂S)₆]
M_r = 1683.65
Trigonal, $[R \overline 3]$
a = 21.7517 (1) Å
c = 7.6269 (1) Å
V = 3125.11 (5) Å³
Z = 3
Mo Kα radiation
μ = 7.79 mm⁻¹
T = 296 K
0.28 × 0.15 × 0.14 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.179, T_max = 0.338
14898 measured reflections
1995 independent reflections
1649 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.027
wR(F²) = 0.061
S = 1.06
1995 reflections
65 parameters
H-atom parameters constrained
Δρ_max = 1.32 e Å⁻³
Δρ_min = −1.64 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N1⋯I1ⁱ	0.83	2.95	3.744 (3)	161
N1—H2N1⋯I1	0.80	2.90	3.698 (4)	173
N2—H1N2⋯I1ⁱⁱ	0.80	2.95	3.756 (3)	177
Symmetry codes: (i) $[-y+{\script{2\over 3}}, x-y+{\script{4\over 3}}, z+{\script{1\over 3}}]$ ; (ii) -x+y-1, -x+1, z.

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812043437/rz5016sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812043437/rz5016Isup2.hkl

checkCIF report

Comment top

Copper(I) complexes with thiones possess a variety of structures ranging from mononuclear three- or four- coordinate species with trigonal planar and tetrahedral Cu(I) respectively to hexameric species with pseudo-four-coordinated geometry (Ahmad et al. 2010; Bowmaker et al., 2009; Li et al., 2005; Lobana et al., 2003, 2005; Khan et al. 2007; Mufakkar et al., 2007, 2009, 2011; Stocker et al., 1997; Zoufala et al., 2007). In some cases mononuclear units further aggregate to form polymeric structures, for example, [Cu₆(PyT)₆I₆]n (where Pyt = pyridine-2-thione) (Li et al., 2005; Lobana et al., 2003, 2005). The present report describes the structure of a hexameric copper(I) complex, iodido(N-methylthiourea)copper(I), that is characterized by significant copper-copper interactions.

The structure of the title complex is shown in Figure 1. The complex is hexanuclear consisting of six [Metu-Cu—I] units, associated through sulfur atoms of N-methylthiourea. Three copper(I) iodides and three Metu ligands are combined through bridging sulfur atoms to form a six-membered trinuclear core, Cu₃S₃I₃. Two six-membered trinuclear cores combine via µ₃-sulfur atoms of Metu to form the centrosymmetric hexanuclear core, Cu₆S₆I₆. Each copper within the complex is coordinated to three sulfur atoms of N-methylthiourea and with one iodide as a terminal ligand adopting a distorted tetrahedral geometry. The angles around Cu vary over the range 98.22 (5)–122.56 (3) °. The Cu—S bond distances are unequal; two are short (2.3164 (10) and 2.3210 (10) Å) and one is long (2.6057 (13) Å). However, they are within the range (2.30–2.60 Å) of the Cu—S bond distances found in other complexes. All of the Cu—I distances are equal (2.5379 (5) Å) and are in agreement with the values reported in the literature. The hexanuclear structure is supported by significant intermolecular N—H···I hydrogen bonding (Table 1) and Cu···Cu interactions. The Cu···Cu distance of 3.0264 (9) Å is close to similar distances observed in other complexes. However, this value is slightly larger than the sum of the van der Waals radii of two copper atoms (2.80 Å) (Siemeling et al. 1997; Singh et al., 1997). Similar hexanuclear core structures have been reported for [Cu₆(Imt)₆I₆]n and [Cu₆(Pyt)₆I₆]n (Imt = imidazolidine-2-thione and Pyt = pyridine-2-thione; Lobana et al., 2003, 2005).

Related literature top

For crystal structures of copper(I) complexes of thiourea-type ligands, see: Ahmad et al. (2010); Bowmaker et al. (2009); Li et al. (2005); Lobana et al. (2003, 2005); Khan et al. (2007); Mufakkar et al. (2007, 2009, 2011); Stocker et al. (1997); Zoufala et al. (2007). For van der Waals radii and cuprophilic interactions, see: Siemeling et al. (1997); Singh et al. (1997).

Experimental top

The title compund was prepared by mixing solutions of copper(I) iodide (1.0 mmol) in 10 ml acetonitrile and N-methylthiourea (1.0 mmol) in acetonitrile (15 ml). The mixture was stirred for half an hour and then filtered. The resulting colourless solution when allowed to stand for 24 h yielded white crystals suitable for X-ray structure analysis.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

Fig. 1. Molecular structure of the title compound with displacement ellipsoids drawn at 50% probability level. Symmetry codes: (a) 1-y, 2+x-y, z; (b) -1-x+y, 1-x, z; (c) -x, 2-y, -z; (d) -1+y, -x+y, -z; (e) 1+x-y, 1+x, -z.

Hexakis(µ₃-1-methylthiourea- κ³S:S:S)hexakis[iodidocopper(I)] top

Crystal data top

[Cu₆I₆(C₂H₆N₂S)₆]	D_x = 2.684 Mg m⁻³
M_r = 1683.65	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3	Cell parameters from 4617 reflections
Hall symbol: -R 3	θ = 2.2–26.6°
a = 21.7517 (1) Å	µ = 7.79 mm⁻¹
c = 7.6269 (1) Å	T = 296 K
V = 3125.11 (5) Å³	Block, colourless
Z = 3	0.28 × 0.15 × 0.14 mm
F(000) = 2340

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	1995 independent reflections
Radiation source: fine-focus sealed tube	1649 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
ϕ and ω scans	θ_max = 29.8°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −30→30
T_min = 0.179, T_max = 0.338	k = −30→30
14898 measured reflections	l = −10→10

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.061	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0202P)² + 17.0381P] where P = (F_o² + 2F_c²)/3
1995 reflections	(Δ/σ)_max < 0.001
65 parameters	Δρ_max = 1.32 e Å⁻³
0 restraints	Δρ_min = −1.64 e Å⁻³

Crystal data top

[Cu₆I₆(C₂H₆N₂S)₆]	Z = 3
M_r = 1683.65	Mo Kα radiation
Trigonal, R3	µ = 7.79 mm⁻¹
a = 21.7517 (1) Å	T = 296 K
c = 7.6269 (1) Å	0.28 × 0.15 × 0.14 mm
V = 3125.11 (5) Å³

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	1995 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	1649 reflections with I > 2σ(I)
T_min = 0.179, T_max = 0.338	R_int = 0.035
14898 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.027	0 restraints
wR(F²) = 0.061	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0202P)² + 17.0381P] where P = (F_o² + 2F_c²)/3
1995 reflections	Δρ_max = 1.32 e Å⁻³
65 parameters	Δρ_min = −1.64 e Å⁻³

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 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

	x	y	z	U_iso*/U_eq
I1	0.082885 (13)	0.829523 (13)	0.17796 (4)	0.04164 (9)
Cu1	0.04125 (3)	0.91805 (3)	0.12398 (9)	0.05416 (16)
N1	−0.10312 (17)	0.76485 (17)	0.3103 (5)	0.0478 (8)
H1N1	−0.1264	0.7232	0.3455	0.057*
H2N1	−0.0616	0.7805	0.2909	0.057*
N2	−0.19615 (15)	0.78569 (16)	0.2972 (4)	0.0394 (7)
H1N2	−0.2067	0.8151	0.2721	0.047*
C1	−0.12810 (18)	0.80754 (17)	0.2777 (5)	0.0330 (7)
C2	−0.2500 (2)	0.7132 (2)	0.3356 (6)	0.0489 (10)
H2A	−0.2945	0.7111	0.3573	0.073*
H2B	−0.2363	0.6970	0.4375	0.073*
H2C	−0.2549	0.6834	0.2375	0.073*
S1	−0.07031 (4)	0.89448 (4)	0.21477 (14)	0.0388 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I1	0.04018 (14)	0.03935 (13)	0.05508 (16)	0.02713 (11)	0.00274 (11)	0.00505 (11)
Cu1	0.0380 (3)	0.0348 (2)	0.0945 (4)	0.0218 (2)	−0.0005 (3)	0.0007 (3)
N1	0.0340 (16)	0.0398 (17)	0.071 (2)	0.0197 (14)	0.0127 (16)	0.0209 (17)
N2	0.0316 (14)	0.0353 (15)	0.0534 (19)	0.0182 (13)	0.0053 (13)	0.0115 (14)
C1	0.0318 (16)	0.0306 (16)	0.0369 (17)	0.0157 (13)	0.0033 (14)	0.0031 (13)
C2	0.0305 (17)	0.042 (2)	0.063 (3)	0.0101 (16)	0.0039 (18)	0.0181 (19)
S1	0.0266 (4)	0.0264 (4)	0.0635 (6)	0.0133 (3)	0.0024 (4)	0.0039 (4)

Geometric parameters (Å, º) top

I1—Cu1	2.5379 (5)	N2—C1	1.317 (4)
Cu1—S1ⁱ	2.3164 (10)	N2—C2	1.449 (5)
Cu1—S1	2.3210 (10)	N2—H1N2	0.8028
Cu1—S1ⁱⁱ	2.6057 (13)	C1—S1	1.735 (3)
Cu1—Cu1ⁱⁱⁱ	3.0264 (9)	C2—H2A	0.9600
Cu1—Cu1ⁱⁱ	3.0264 (9)	C2—H2B	0.9600
N1—C1	1.313 (4)	C2—H2C	0.9600
N1—H1N1	0.8316	S1—Cu1^iv	2.3164 (10)
N1—H2N1	0.8039	S1—Cu1ⁱⁱⁱ	2.6057 (13)

S1ⁱ—Cu1—S1	98.22 (5)	C1—N2—C2	124.5 (3)
S1ⁱ—Cu1—I1	122.56 (3)	C1—N2—H1N2	113.8
S1—Cu1—I1	120.95 (3)	C2—N2—H1N2	121.2
S1ⁱ—Cu1—S1ⁱⁱ	102.80 (4)	N1—C1—N2	120.7 (3)
S1—Cu1—S1ⁱⁱ	102.67 (4)	N1—C1—S1	119.5 (3)
I1—Cu1—S1ⁱⁱ	106.80 (3)	N2—C1—S1	119.7 (3)
S1ⁱ—Cu1—Cu1ⁱⁱⁱ	118.09 (3)	N2—C2—H2A	109.5
S1—Cu1—Cu1ⁱⁱⁱ	56.49 (3)	N2—C2—H2B	109.5
I1—Cu1—Cu1ⁱⁱⁱ	118.39 (2)	H2A—C2—H2B	109.5
S1ⁱⁱ—Cu1—Cu1ⁱⁱⁱ	47.86 (3)	N2—C2—H2C	109.5
S1ⁱ—Cu1—Cu1ⁱⁱ	56.52 (3)	H2A—C2—H2C	109.5
S1—Cu1—Cu1ⁱⁱ	118.03 (3)	H2B—C2—H2C	109.5
I1—Cu1—Cu1ⁱⁱ	119.84 (2)	C1—S1—Cu1^iv	115.65 (12)
S1ⁱⁱ—Cu1—Cu1ⁱⁱ	47.96 (3)	C1—S1—Cu1	115.53 (12)
Cu1ⁱⁱⁱ—Cu1—Cu1ⁱⁱ	85.08 (3)	Cu1^iv—S1—Cu1	123.88 (5)
C1—N1—H1N1	126.2	C1—S1—Cu1ⁱⁱⁱ	98.60 (12)
C1—N1—H2N1	116.1	Cu1^iv—S1—Cu1ⁱⁱⁱ	75.63 (3)
H1N1—N1—H2N1	117.6	Cu1—S1—Cu1ⁱⁱⁱ	75.55 (3)

C2—N2—C1—N1	−7.1 (6)	Cu1ⁱⁱⁱ—Cu1—S1—C1	92.76 (14)
C2—N2—C1—S1	174.9 (3)	Cu1ⁱⁱ—Cu1—S1—C1	154.78 (14)
N1—C1—S1—Cu1^iv	171.7 (3)	S1ⁱ—Cu1—S1—Cu1^iv	57.15 (8)
N2—C1—S1—Cu1^iv	−10.3 (4)	I1—Cu1—S1—Cu1^iv	−166.73 (4)
N1—C1—S1—Cu1	15.6 (4)	S1ⁱⁱ—Cu1—S1—Cu1^iv	−48.03 (7)
N2—C1—S1—Cu1	−166.4 (3)	Cu1ⁱⁱⁱ—Cu1—S1—Cu1^iv	−61.20 (5)
N1—C1—S1—Cu1ⁱⁱⁱ	93.6 (3)	Cu1ⁱⁱ—Cu1—S1—Cu1^iv	0.83 (8)
N2—C1—S1—Cu1ⁱⁱⁱ	−88.4 (3)	S1ⁱ—Cu1—S1—Cu1ⁱⁱⁱ	118.35 (4)
S1ⁱ—Cu1—S1—C1	−148.90 (13)	I1—Cu1—S1—Cu1ⁱⁱⁱ	−105.53 (3)
I1—Cu1—S1—C1	−12.78 (15)	S1ⁱⁱ—Cu1—S1—Cu1ⁱⁱⁱ	13.17 (4)
S1ⁱⁱ—Cu1—S1—C1	105.92 (14)	Cu1ⁱⁱ—Cu1—S1—Cu1ⁱⁱⁱ	62.03 (4)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···I1^v	0.83	2.95	3.744 (3)	161
N1—H2N1···I1	0.80	2.90	3.698 (4)	173
N2—H1N2···I1^iv	0.80	2.95	3.756 (3)	177

Symmetry codes: (iv) −x+y−1, −x+1, z; (v) −y+2/3, x−y+4/3, z+1/3.

Experimental details

Crystal data
Chemical formula	[Cu₆I₆(C₂H₆N₂S)₆]
M_r	1683.65
Crystal system, space group	Trigonal, R3
Temperature (K)	296
a, c (Å)	21.7517 (1), 7.6269 (1)
V (Å³)	3125.11 (5)
Z	3
Radiation type	Mo Kα
µ (mm⁻¹)	7.79
Crystal size (mm)	0.28 × 0.15 × 0.14

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2008)
T_min, T_max	0.179, 0.338
No. of measured, independent and observed [I > 2σ(I)] reflections	14898, 1995, 1649
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.700

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.027, 0.061, 1.06
No. of reflections	1995
No. of parameters	65
H-atom treatment	H-atom parameters constrained
	w = 1/[σ²(F_o²) + (0.0202P)² + 17.0381P] where P = (F_o² + 2F_c²)/3
Δρ_max, Δρ_min (e Å⁻³)	1.32, −1.64

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N1···I1ⁱ	0.8300	2.9500	3.744 (3)	161.00
N1—H2N1···I1	0.8000	2.9000	3.698 (4)	173.00
N2—H1N2···I1ⁱⁱ	0.8000	2.9500	3.756 (3)	177.00

Symmetry codes: (i) −y+2/3, x−y+4/3, z+1/3; (ii) −x+y−1, −x+1, z.

Acknowledgements

The authors gratefully acknowledge Universiti Sains Malaysia and Government College University, Lahore, for providing X-ray facilities.

References

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