Tetra-μ-acetato-bis­[(1,3-benzothia­zole)copper(II)](Cu—Cu)

Hermle, J.; Meyer, G.

doi:10.1107/S1600536811027140

metal-organic compounds

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Volume 67| Part 8| August 2011| Page m1089

doi:10.1107/S1600536811027140

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Tetra-μ-acetato-bis[(1,3-benzothiazole)copper(II)](Cu—Cu)

Johannes Hermle ^a and Gerd Meyer ^a ^*

^aDepartment für Chemie, Institut für Anorganische Chemie, Universität zu Köln, Greinstrasse 6, 50939 Köln, Germany
^*Correspondence e-mail: Gerd.Meyer@uni-koeln.de

(Received 24 May 2011; accepted 6 July 2011; online 13 July 2011)

The title compound, [Cu₂(CH₃CO₂)₄(C₇H₅NS)₂] or [(C₇H₅NS)Cu]₂(μ-O₂CCH₃)₄, crystallizes with one molecule per unit cell. The coordination number of copper is six with four basal O atoms, one axial N atom and one axial Cu atom. Four acetate ligands act as bidentate linker and connect two Cu atoms, with a crystallographic inversion center located at the mid-point of the Cu—Cu bond. The acetate ligands form slightly distorted square planes around each metal ion, while the copper ions are displaced by 0.2089 (4) Å from these planes towards the N atoms. Thus, the Cu—Cu distance is elongated to 2.6378 (7) Å, compared with the 2.2180 (7) Å distance between the two basal planes. The angle between the basal plane and the Cu—N bond is 4.84 (6)°.

Related literature

The structural prototype of (LCu)₂(μ-O₂CCH₃)₄ complexes is the crystal structure of cupric acetate monohydrate (L = water), see: Van Niekerk & Schoening (1953 ); Ferguson & Glidewell (2003 ). For similar structures with L = benzimidazole, see: Bukowska-Strzyżewska et al. (1982) and L = 2-amino-benzothiazole, see: Sun et al. (2007 ). For theoretical studies see: Rodríguez-Fortea et al. (2001) and for magnetic properties of dinuclear copper complexes, see: Tokii & Muto (1983 ). For FIR spectroscopic data and the magnetic moment of the complex with L = benzothiazole, see: Ford et al. (1968 ).

Experimental

Crystal data

[Cu₂(C₂H₃O₂)₄(C₇H₅NS)₂]
M_r = 633.66
Triclinic, $[P \overline 1]$
a = 7.185 (1) Å
b = 8.1918 (12) Å
c = 11.8265 (16) Å
α = 106.516 (16)°
β = 106.429 (16)°
γ = 97.344 (17)°
V = 623.49 (18) Å³
Z = 1
Mo Kα radiation
μ = 1.92 mm⁻¹
T = 293 K
0.3 × 0.2 × 0.1 mm

Data collection

Stoe IPDS I diffractometer
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1999 ) T_min = 0.575, T_max = 0.840
7525 measured reflections
2784 independent reflections
2092 reflections with I > 2σ(I)
R_int = 0.038

Refinement

R[F² > 2σ(F²)] = 0.032
wR(F²) = 0.075
S = 0.97
2784 reflections
165 parameters
H-atom parameters constrained
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.45 e Å⁻³

Data collection: X-AREA (Stoe & Cie, 2001 ); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SIR92 (Altomare et al., 1993 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: DIAMOND (Brandenburg, 2011 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811027140/hg5042sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811027140/hg5042Isup2.hkl

checkCIF report

Comment top

Copper(II) acetate complexes of the general formula [LCu]₂(µ²-OAc)₄, where L is a ligand with an oxygen or nitrogen ligator atom have been well explored. The structural evidence of a copper-copper bond was given by van Niekerk & Schoening in 1953. The title compound is a dinuclear complex disposed around an inversion center located at the mid-point of the Cu—Cu bond. The coordination environment of Cu(II) ions can be described as a slightly distorted octahedron, with each copper atom being surrounded by four µ²-bridging bidentate acetate ligands in the basal plane and one benzothiazole ligand in one axial position (Fig. 1). The sixth coordination site is occupied by the neighbouring copper(II) atom. The Cu—Cu distance is about 0.02 Å longer as in Cu(II) acetate monohydrate [(H₂O)Cu]₂(µ²-OAc)₄ with 2.6157 (8) Å (Ferguson & Glidewell 2003) and 0.03 Å shorter than in the benzimidazole complex 2.663 (1) Å (Bukowska-Strzyzewska et al. 1982). To our knowledge there is only one more dinuclear complex with acetate ligands and a benzothiazole derivative known (Sun et al. 2007). The magnetic moment of [(C₇H₅NS)Cu]₂(µ²-OAc)₄ of µ = 1.42 µ_B at room temperature is an evidence for Cu—Cu interactions with coupling of the electron spins, Ford et al. 1968. Magnetic susceptibilities of benzothiazole, thiazole and thiazole derivatives have been measured by Tokii & Muto 1983. Theoretical studies on intramolecular antiferromagnetic coupling in carboxylato-bridged dinuclear copper(II) complexes have been performed by Rodríguez-Fortea et al. 2001.

Related literature top

For structural prototypes of (LCu)₂(µ²-OAc)₄ complexes with L = water is the crystal structure of cupric acetate monohydrate, see: Van Niekerk & Schoening (1953); Ferguson & Glidewell (2003). For similar structures with L = benzimidazole, see: Bukowska-Strzyżewska et al. (1982) and L = 2-amino-benzothiazole, see: Sun et al. (2007). For theoretical studies see: Rodríguez-Fortea et al. (2001) and for magnetic properties of dinuclear copper complexes, see: Tokii & Muto (1983). For FIR spectroscopic data and the magnetic moment of the complex with L = benzothiazole, see: Ford et al. (1968).

Experimental top

Green platelets of [(C₇H₅NS)Cu]₂(µ²-OAc)₄ were obtained by the reaction of 0.20 g cupric acetate monohydrate (1 mmol, Merck) with 0.22 ml benzothiazole (0.27 g, 2 mmol, Acros) in 20 ml of ethanol at ambient temperature by slow evaporation of the solvent within two weeks. Yield: 0.59 g (93%). Mp: 206 °C (Decomp.). UV/VIS: (chloroform) λ _max 358, 690 nm. IR: 3080(w), 3057(w), 2995(w), 2927(w), 1612(s), 1562(m), 1468(m), 1454(m), 1431(s), 1348(m), 1321(w), 1304(m), 1273(w), 1205(w), 1155(w), 1066(w), 1049(w), 1030(w), 1016(w), 949(w), 897(m), 870(w), 856(w), 810(w), 762(m), 733(m), 681(m), 627(m), 534(w), 507(w), 424(w) cm^-1. Elem. Anal. calcd for C₂₂H₂₂Cu₂N₂O₈S₂: C, 41.70; H, 3.50; N, 4.42; S, 10.12; found: C, 41.30; H, 3.30; N, 4.17; S, 10.14.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2011); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms. [Symmetry code: (i) -x + 1, -y + 1, -z + 1]
	Fig. 2. The packing of (I), viewed along the b axis, H atoms have been omitted for clarity.
	Fig. 3. The packing of (I), viewed along the a axis, H atoms have been omitted for clarity.

Tetra-µ-acetato-bis[(1,3-benzothiazole)copper(II)](Cu—Cu) top

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₇H₅NS)₂]	Z = 1
M_r = 633.66	F(000) = 322
Triclinic, P1	D_x = 1.688 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.185 (1) Å	Cell parameters from 1512 reflections
b = 8.1918 (12) Å	θ = 3.8–56.3°
c = 11.8265 (16) Å	µ = 1.92 mm⁻¹
α = 106.516 (16)°	T = 293 K
β = 106.429 (16)°	Plate, green
γ = 97.344 (17)°	0.3 × 0.2 × 0.1 mm
V = 623.49 (18) Å³

Data collection top

Stoe IPDS I diffractometer	2784 independent reflections
Radiation source: fine-focus sealed tube	2092 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.038
Detector resolution: 0 pixels mm^-1	θ_max = 28.1°, θ_min = 2.7°
Oscillation scans	h = −8→8
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1999)	k = −10→10
T_min = 0.575, T_max = 0.840	l = −15→15
7525 measured reflections

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)] = 0.032	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.075	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0379P)²] where P = (F_o² + 2F_c²)/3
2784 reflections	(Δ/σ)_max = 0.013
165 parameters	Δρ_max = 0.45 e Å⁻³
0 restraints	Δρ_min = −0.45 e Å⁻³

Crystal data top

[Cu₂(C₂H₃O₂)₄(C₇H₅NS)₂]	γ = 97.344 (17)°
M_r = 633.66	V = 623.49 (18) Å³
Triclinic, P1	Z = 1
a = 7.185 (1) Å	Mo Kα radiation
b = 8.1918 (12) Å	µ = 1.92 mm⁻¹
c = 11.8265 (16) Å	T = 293 K
α = 106.516 (16)°	0.3 × 0.2 × 0.1 mm
β = 106.429 (16)°

Data collection top

Stoe IPDS I diffractometer	2784 independent reflections
Absorption correction: numerical (X-SHAPE; Stoe & Cie, 1999)	2092 reflections with I > 2σ(I)
T_min = 0.575, T_max = 0.840	R_int = 0.038
7525 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.032	0 restraints
wR(F²) = 0.075	H-atom parameters constrained
S = 0.97	Δρ_max = 0.45 e Å⁻³
2784 reflections	Δρ_min = −0.45 e Å⁻³
165 parameters

Special details top

Experimental. A single crystal suitable for X-ray diffraction was selected under a polarization microscope and sealed in a capillary tube. Complete scattering intensities data sets were collected with an imaging plate diffractometer (IPDS I, Stoe & Cie). The data were corrected for Lorentz and polarization effects. A numerical absorption correction based on crystal-shape optimization was applied for all data.

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. Hydrogen atoms were placed in idealized positions and constrained riding on their parent atoms [C–H = 0.93–0.96 Å with U_iso(H) = 1.2 U_eq(C)]. The last cycles of refinement included atomic positions for all atoms, anisotropic thermal parameters for all non-hydrogen atoms and isotropic thermal parameters for all hydrogen atoms.

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

	x	y	z	U_iso*/U_eq
Cu1	0.43471 (5)	0.46234 (4)	0.58527 (3)	0.02316 (11)
S1	0.04719 (13)	0.43274 (11)	0.83857 (7)	0.0430 (2)
N1	0.2932 (4)	0.4019 (3)	0.71570 (19)	0.0265 (5)
O3	0.6747 (3)	0.6371 (3)	0.70893 (18)	0.0428 (5)
O4	0.7826 (3)	0.7015 (3)	0.56499 (17)	0.0390 (5)
O1	0.5911 (3)	0.2831 (3)	0.56937 (19)	0.0374 (5)
C2	0.3612 (4)	0.3329 (3)	0.8112 (2)	0.0259 (6)
O2	0.6990 (4)	0.3443 (3)	0.4247 (2)	0.0427 (6)
C6	0.3008 (5)	0.2858 (4)	0.9930 (3)	0.0411 (8)
H6	0.2271	0.2953	1.0468	0.049*
C4	0.5758 (5)	0.2012 (4)	0.9319 (3)	0.0458 (8)
H4	0.6848	0.1503	0.9462	0.055*
C5	0.4659 (6)	0.2169 (4)	1.0127 (3)	0.0462 (9)
H5	0.5055	0.1798	1.0813	0.055*
C11	0.9534 (6)	0.8715 (4)	0.7759 (3)	0.0542 (10)
H11A	0.9499	0.8716	0.8564	0.081*
H11B	0.9337	0.9812	0.7663	0.081*
H11C	1.0803	0.8550	0.7693	0.081*
C9	0.7821 (5)	0.1025 (4)	0.4827 (3)	0.0415 (7)
H9A	0.9197	0.1415	0.4931	0.062*
H9C	0.7166	0.0146	0.4018	0.062*
H9B	0.7733	0.0542	0.5466	0.062*
C1	0.1335 (5)	0.4564 (4)	0.7205 (3)	0.0344 (7)
H1	0.0685	0.5058	0.6633	0.041*
C3	0.5264 (5)	0.2595 (4)	0.8310 (3)	0.0359 (7)
H3	0.6015	0.2501	0.7780	0.043*
C7	0.2462 (5)	0.3417 (3)	0.8892 (2)	0.0307 (6)
C10	0.7917 (4)	0.7261 (3)	0.6755 (2)	0.0288 (6)
C8	0.6835 (4)	0.2542 (3)	0.4930 (2)	0.0278 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0256 (2)	0.02769 (17)	0.02156 (16)	0.00738 (12)	0.01074 (12)	0.01282 (12)
S1	0.0358 (5)	0.0654 (5)	0.0383 (4)	0.0139 (4)	0.0222 (4)	0.0223 (4)
N1	0.0267 (14)	0.0329 (12)	0.0228 (11)	0.0055 (9)	0.0097 (9)	0.0127 (9)
O3	0.0453 (15)	0.0499 (12)	0.0239 (10)	−0.0096 (10)	0.0076 (9)	0.0115 (9)
O4	0.0353 (13)	0.0522 (13)	0.0247 (10)	−0.0037 (10)	0.0095 (9)	0.0124 (9)
O1	0.0467 (14)	0.0429 (11)	0.0437 (12)	0.0252 (10)	0.0268 (10)	0.0275 (10)
C2	0.0283 (16)	0.0263 (12)	0.0203 (12)	−0.0001 (10)	0.0065 (10)	0.0082 (10)
O2	0.0588 (16)	0.0442 (12)	0.0552 (13)	0.0307 (11)	0.0389 (12)	0.0338 (11)
C6	0.061 (2)	0.0362 (16)	0.0259 (14)	−0.0033 (14)	0.0177 (14)	0.0124 (13)
C4	0.056 (2)	0.0381 (16)	0.0425 (18)	0.0160 (15)	0.0071 (16)	0.0191 (15)
C5	0.073 (3)	0.0337 (16)	0.0285 (15)	0.0051 (15)	0.0081 (15)	0.0182 (13)
C11	0.055 (2)	0.050 (2)	0.0364 (18)	−0.0127 (16)	0.0009 (16)	0.0081 (15)
C9	0.045 (2)	0.0338 (15)	0.056 (2)	0.0195 (14)	0.0224 (16)	0.0201 (15)
C1	0.0300 (18)	0.0488 (17)	0.0292 (14)	0.0109 (13)	0.0104 (12)	0.0188 (13)
C3	0.040 (2)	0.0374 (15)	0.0337 (15)	0.0099 (13)	0.0121 (13)	0.0175 (13)
C7	0.0354 (18)	0.0305 (14)	0.0236 (13)	−0.0010 (11)	0.0114 (11)	0.0074 (11)
C10	0.0269 (17)	0.0295 (14)	0.0261 (13)	0.0053 (11)	0.0031 (11)	0.0102 (11)
C8	0.0253 (16)	0.0263 (13)	0.0327 (14)	0.0073 (11)	0.0087 (11)	0.0115 (11)

Geometric parameters (Å, º) top

Cu1—O1	1.9589 (19)	C6—C5	1.367 (5)
Cu1—O2ⁱ	1.9689 (19)	C6—C7	1.401 (3)
Cu1—O3	1.978 (2)	C6—H6	0.9300
Cu1—O4ⁱ	1.984 (2)	C4—C3	1.381 (4)
Cu1—N1	2.203 (2)	C4—C5	1.391 (5)
Cu1—Cu1ⁱ	2.6378 (7)	C4—H4	0.9300
S1—C1	1.727 (3)	C5—H5	0.9300
S1—C7	1.732 (3)	C11—C10	1.497 (4)
N1—C1	1.293 (4)	C11—H11A	0.9600
N1—C2	1.398 (3)	C11—H11B	0.9600
O3—C10	1.261 (3)	C11—H11C	0.9600
O4—C10	1.246 (3)	C9—C8	1.500 (4)
O4—Cu1ⁱ	1.984 (2)	C9—H9A	0.9600
O1—C8	1.253 (3)	C9—H9C	0.9600
C2—C3	1.390 (4)	C9—H9B	0.9600
C2—C7	1.396 (4)	C1—H1	0.9300
O2—C8	1.256 (3)	C3—H3	0.9300
O2—Cu1ⁱ	1.9689 (19)

O1—Cu1—O2ⁱ	167.71 (7)	C5—C4—H4	119.3
O1—Cu1—O3	90.12 (10)	C6—C5—C4	121.3 (2)
O2ⁱ—Cu1—O3	88.37 (10)	C6—C5—H5	119.4
O1—Cu1—O4ⁱ	88.25 (10)	C4—C5—H5	119.4
O2ⁱ—Cu1—O4ⁱ	90.67 (10)	C10—C11—H11A	109.5
O3—Cu1—O4ⁱ	167.89 (8)	C10—C11—H11B	109.5
O1—Cu1—N1	100.05 (8)	H11A—C11—H11B	109.5
O2ⁱ—Cu1—N1	92.24 (8)	C10—C11—H11C	109.5
O3—Cu1—N1	98.77 (8)	H11A—C11—H11C	109.5
O4ⁱ—Cu1—N1	93.33 (8)	H11B—C11—H11C	109.5
O1—Cu1—Cu1ⁱ	84.48 (6)	C8—C9—H9A	109.5
O2ⁱ—Cu1—Cu1ⁱ	83.24 (6)	C8—C9—H9C	109.5
O3—Cu1—Cu1ⁱ	85.57 (6)	H9A—C9—H9C	109.5
O4ⁱ—Cu1—Cu1ⁱ	82.33 (6)	C8—C9—H9B	109.5
N1—Cu1—Cu1ⁱ	173.67 (6)	H9A—C9—H9B	109.5
C1—S1—C7	88.85 (13)	H9C—C9—H9B	109.5
C1—N1—C2	110.6 (2)	N1—C1—S1	116.61 (19)
C1—N1—Cu1	118.25 (16)	N1—C1—H1	121.7
C2—N1—Cu1	130.51 (18)	S1—C1—H1	121.7
C10—O3—Cu1	121.50 (17)	C4—C3—C2	118.0 (3)
C10—O4—Cu1ⁱ	125.44 (19)	C4—C3—H3	121.0
C8—O1—Cu1	123.50 (15)	C2—C3—H3	121.0
C3—C2—C7	120.5 (2)	C2—C7—C6	120.8 (3)
C3—C2—N1	125.5 (2)	C2—C7—S1	109.93 (18)
C7—C2—N1	114.0 (2)	C6—C7—S1	129.2 (2)
C8—O2—Cu1ⁱ	124.42 (18)	O4—C10—O3	124.7 (3)
C5—C6—C7	117.9 (3)	O4—C10—C11	117.7 (3)
C5—C6—H6	121.0	O3—C10—C11	117.6 (2)
C7—C6—H6	121.0	O1—C8—O2	124.2 (2)
C3—C4—C5	121.4 (3)	O1—C8—C9	117.9 (2)
C3—C4—H4	119.3	O2—C8—C9	118.0 (3)

Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	[Cu₂(C₂H₃O₂)₄(C₇H₅NS)₂]
M_r	633.66
Crystal system, space group	Triclinic, P1
Temperature (K)	293
a, b, c (Å)	7.185 (1), 8.1918 (12), 11.8265 (16)
α, β, γ (°)	106.516 (16), 106.429 (16), 97.344 (17)
V (Å³)	623.49 (18)
Z	1
Radiation type	Mo Kα
µ (mm⁻¹)	1.92
Crystal size (mm)	0.3 × 0.2 × 0.1

Data collection
Diffractometer	Stoe IPDS I diffractometer
Absorption correction	Numerical (X-SHAPE; Stoe & Cie, 1999)
T_min, T_max	0.575, 0.840
No. of measured, independent and observed [I > 2σ(I)] reflections	7525, 2784, 2092
R_int	0.038
(sin θ/λ)_max (Å⁻¹)	0.663

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.075, 0.97
No. of reflections	2784
No. of parameters	165
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.45, −0.45

Computer programs: X-AREA (Stoe & Cie, 2001), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2011), WinGX (Farrugia, 1999).

Acknowledgements

The authors are grateful to Universität zu Köln for financial support.

References

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