Bis­(tetra-n-butyl­ammonium) tetrakis­[chloro(μ3-sulfido)copper(I)]­tungstate(VI): a second polymorph

Hossaini Sadr, M.; Seyed Ahmadian, S.M.; Brooks, N.R.; Clegg, W.

doi:10.1107/S1600536804030582

metal-organic compounds

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Volume 60| Part 12| December 2004| Pages m1952-m1954

https://doi.org/10.1107/S1600536804030582

Bis(tetra-n-butylammonium) tetrakis[chloro(μ₃-sulfido)copper(I)]tungstate(VI): a second polymorph

Moayad Hossaini Sadr,^a Seyed Masoud Seyed Ahmadian,^a Neil R. Brooks ^b and William Clegg ^b ^*

^aDepartment of Chemistry, Faculty of Science, Azarbaijan University of Tarbiat Moallem, Tabriz, Iran, and ^bSchool of Natural Sciences (Chemistry), University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, England
^*Correspondence e-mail: w.clegg@ncl.ac.uk

(Received 22 November 2004; accepted 23 November 2004; online 27 November 2004)

The title compound, (C₁₆H₃₆N)₂[WS₄(CuCl)₄], has been obtained in a second polymorphic form. The anion, in which four of the six S⋯S edges of the central WS₄ tetrahedron are bridged by CuCl neutral molecular units to give a planar pentanuclear WCu₄ framework, is disordered on a crystallographic fourfold rotation axis, requiring equal occupancy of two sets of four positions for the S atoms. Copper has distorted trigonal planar coordination, involving two μ₃-S atoms and a terminal Cl atom. The two independent cations lie on positions of symmetry $[\overline 4]$ .

Comment

We recently reported the structure of a second tetragonal polymorph of (NⁿBu₄)₂[MoS₄(CuCl)₄] in space group P4/n (Brooks et al., 2004 ); the first polymorph, in space group I $[\overline 4]$ , had very similar cell parameters (Sécheresse et al., 1991 ). The title tungsten analogue, (I), was also prepared as a precursor for the synthesis of complexes with the WS₄Cu₄ core and a range of terminal ligands (Hossaini Sadr et al., 2004 ) and it is found to be isostructural with the second polymorph of the molybdenum complex. There are no significant differences between the two structures, and a full discussion was given in the previous report.

Sécheresse et al. (1991) reported that the compound was isostructural with the molybdenum analogue in its body-centred tetragonal form, though only the cell parameters and space group are given and the Cambridge Structural Database entry (refcode SORLIU; Version 5.25; Allen, 2002 ) contains no atomic coordinates or other information indicating that the crystal structure has been fully determined. Two other salts of the same anion have been reported: in the tetraphenylphosphonium salt (Clegg et al., 1987 ), the anion forms dimers through pairs of chloro bridges between Cu atoms, and in the tetra-n-propylammonium salt (Sécheresse et al., 1991), further bridges are formed, linking the anions into a polymeric chain. A combination of terminal and bridging halogen atoms has been found in some other [MS₄(CuX)_n]²⁻ complexes (Nicholson et al., 1983 ), and the interplay is clearly subtle.

Figure 1
The structure of the anion, with atom labels for the asymmetric unit and 50% probability displacement ellipsoids. Only one component of the disorder is shown for the S atoms.

Figure 2
The anion with both disorder components, viewed along the crystallographic fourfold rotation axis. The second disorder component is shown with dashed ellipsoids and bonds; four of the W—S bonds are obscured by the four that are visible.

Experimental

A mixture of (NH₄)₂[WS₄] (0.35 g, 1.0 mmol), solid (NBu₄)Br (0.65 g, 2.0 mmol) and CuCl (0.40 g, 4.0 mmol) in dry acetone (120 ml) was stirred vigorously in air at ambient temperature for 14 h. The resulting solution was filtered and the filtrate was concentrated to about 20 ml. The product was precipitated from the solution by addition of diethyl ether (4 × 25 ml) and removal of the supernatant solution each time. The orange–red precipitate was washed with diethyl ether (3 × 20 ml) and dried in vacuo. A saturated acetone solution of the complex was rendered slightly turbid by addition of n-pentane and air-stable orange crystals suitable for X-ray diffraction were collected after 48 h. The crystals were washed with diethyl ether several times. IR (KBr, cm⁻¹): (W—S) 441 (s).

Crystal data

(C₁₆H₃₆N)₂[WCu₄Cl₄S₄]
M_r = 1192.97
Tetragonal, P4/n
a = 13.3652 (5) Å
c = 13.668 (2) Å
V = 2441.5 (4) Å³
Z = 2
D_x = 1.623 Mg m⁻³
Mo Kα radiation
Cell parameters from 54 reflections
θ = 2.5–25.0°
μ = 4.47 mm⁻¹
T = 150 (2) K
Plate, purple
0.44 × 0.38 × 0.10 mm

Data collection

Nonius KappaCCD diffractometer
φ and ω scans
Absorption correction: multi-scan (SADABS; Sheldrick, 1997 ) T_min = 0.147, T_max = 0.637
42475 measured reflections
2804 independent reflections
2441 reflections with I > 2σ(I)
R_int = 0.047
θ_max = 27.5°
h = −17 → 17
k = −17 → 17
l = −17 → 17

Refinement

Refinement on F²
R[F² > 2σ(F²)] = 0.022
wR(F²) = 0.056
S = 1.11
2804 reflections
119 parameters
H-atom parameters constrained
w = 1/[σ²(F_o²) + (0.0199P)² + 2.9221P] where P = (F_o² + 2F_c²)/3
(Δ/σ)_max = 0.001
Δρ_max = 1.33 e Å⁻³
Δρ_min = −0.59 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

W—S	2.2435 (13)
W—S′	2.2555 (13)
Cu—Cl	2.1586 (7)
Cu—S	2.2302 (13)
Cu—Sⁱ	2.2296 (14)
Cu—S′	2.2882 (13)
Cu—S′ⁱ	2.2961 (13)

S—W—Sⁱⁱ	109.61 (8)
S—W—S′ⁱⁱⁱ	108.63 (5)
S—W—S′ⁱ	108.86 (5)
S′—W—S′ⁱⁱ	112.23 (7)
Cl—Cu—S	124.08 (4)
Cl—Cu—Sⁱ	124.19 (4)
Cl—Cu—S′	127.81 (4)
Cl—Cu—S′ⁱ	128.00 (4)
Sⁱ—Cu—S′	107.96 (5)
S—Cu—S′ⁱ	107.89 (5)
W—S—Cu	72.34 (4)
W—S—Cuⁱⁱⁱ	72.35 (4)
Cu—S—Cuⁱⁱⁱ	113.64 (6)
W—S′—Cu	71.05 (4)
W—S′—Cuⁱⁱⁱ	70.91 (4)
Cu—S′—Cuⁱⁱⁱ	109.02 (6)

N1—C1—C2—C3	−174.12 (19)
C1—C2—C3—C4	−172.5 (2)
N2—C5—C6—C7	−173.2 (2)
C5—C6—C7—C8	74.5 (3)
Symmetry codes: (i) $[{\script{1\over 2}}-y,x,z]$ ; (ii) $[{\script{1\over 2}}-x,{\script{1\over 2}}-y,z]$ ; (iii) $[y,{\script{1\over 2}}-x,z]$ .

The space group P4/n was determined unambiguously from the systematic absences and confirmed by successful refinement; there is pseudo-body-centring, reflections with h + k + l = 2n + 1 having an average intensity approximately half that for reflections with h + k + l = 2n. Atom W lies on a crystallographic fourfold rotation axis (4 or C₄), while the two N atoms lie at improper fourfold rotation sites ( $[\overline 4]$ or S₄); thus, the asymmetric unit of the structure consists of one-quarter of the anion and two separate quarters of cations. The coordinates of the isostructural molybdenum complex were taken as starting parameters for refinement. As in the previous structure, the S atoms are disordered equally over two independent sets of equivalent positions, generating eight positions around the central W atom; each anion contains two S atoms from one set (S) and two from the other (S′). H atoms were placed geometrically (C—H = 0.98–0.99 Å) and refined with a riding model; U_iso(H) values were constrained to be 1.2 (1.5 for methyl groups) times U_eq of the carrier atom. The final difference map contains one peak greater than 1 e Å⁻³, which lies 0.88 Å from the W atom.

Data collection: COLLECT (Nonius, 1998 ); cell refinement: EvalCCD (Duisenberg et al., 2003 ); data reduction: EvalCCD; program(s) used to solve structure: SHELXTL (Sheldrick, 2001 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.<

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536804030582/lh6324sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536804030582/lh6324Isup2.hkl

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: EVALCCD (Duisenberg et al., 2003); data reduction: EVALCCD; program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Bis(tetra-n-butylammonium) tetrakis[chloro(µ₃-sulfido)copper(I)]tungstate(VI) top

Crystal data top

(C₁₆H₃₆N)₂[WCu₄Cl₄S₄]	D_x = 1.623 Mg m⁻³
M_r = 1192.97	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P4/n	Cell parameters from 54 reflections
a = 13.3652 (5) Å	θ = 2.5–25.0°
c = 13.668 (2) Å	µ = 4.47 mm⁻¹
V = 2441.5 (4) Å³	T = 150 K
Z = 2	Plate, purple
F(000) = 1200	0.44 × 0.38 × 0.10 mm

Data collection top

Nonius KappaCCD diffractometer	2804 independent reflections
Radiation source: sealed tube	2441 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.047
φ and ω scans	θ_max = 27.5°, θ_min = 4.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1997)	h = −17→17
T_min = 0.147, T_max = 0.637	k = −17→17
42475 measured reflections	l = −17→17

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)] = 0.022	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.056	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0199P)² + 2.9221P] where P = (F_o² + 2F_c²)/3
2804 reflections	(Δ/σ)_max = 0.001
119 parameters	Δρ_max = 1.33 e Å⁻³
0 restraints	Δρ_min = −0.59 e Å⁻³

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
W	0.2500	0.2500	0.267886 (14)	0.02507 (7)
Cu	0.06514 (2)	0.31948 (3)	0.26253 (2)	0.03166 (9)
Cl	−0.08556 (5)	0.37638 (6)	0.25110 (4)	0.03595 (15)
S	0.19336 (9)	0.37493 (11)	0.17328 (11)	0.0348 (3)	0.50
S'	0.19179 (9)	0.37743 (10)	0.35989 (10)	0.0308 (3)	0.50
N1	0.7500	0.2500	0.0000	0.0245 (8)
C1	0.83182 (18)	0.28797 (18)	−0.06785 (18)	0.0269 (5)
H1A	0.8486	0.2336	−0.1142	0.032*
H1B	0.8039	0.3439	−0.1067	0.032*
C2	0.92826 (19)	0.32369 (19)	−0.02113 (19)	0.0305 (5)
H2A	0.9629	0.2670	0.0108	0.037*
H2B	0.9136	0.3749	0.0292	0.037*
C3	0.9947 (2)	0.3684 (2)	−0.1013 (2)	0.0414 (7)
H3A	1.0002	0.3198	−0.1558	0.050*
H3B	0.9625	0.4296	−0.1271	0.050*
C4	1.0987 (2)	0.3942 (3)	−0.0655 (3)	0.0564 (9)
H4A	1.0939	0.4415	−0.0109	0.085*
H4B	1.1370	0.4248	−0.1189	0.085*
H4C	1.1327	0.3332	−0.0436	0.085*
N2	0.7500	0.2500	0.5000	0.0260 (8)
C5	0.82832 (19)	0.29542 (19)	0.56795 (18)	0.0290 (5)
H5A	0.7941	0.3420	0.6132	0.035*
H5B	0.8575	0.2410	0.6079	0.035*
C6	0.9133 (2)	0.3515 (2)	0.5185 (2)	0.0410 (7)
H6A	0.8868	0.4120	0.4858	0.049*
H6B	0.9444	0.3083	0.4681	0.049*
C7	0.9923 (2)	0.3818 (2)	0.5947 (2)	0.0440 (7)
H7A	1.0361	0.4338	0.5659	0.053*
H7B	0.9579	0.4119	0.6517	0.053*
C8	1.0565 (2)	0.2961 (3)	0.6297 (3)	0.0515 (8)
H8A	1.0142	0.2456	0.6612	0.077*
H8B	1.1058	0.3210	0.6769	0.077*
H8C	1.0912	0.2660	0.5738	0.077*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
W	0.02701 (8)	0.02701 (8)	0.02119 (11)	0.000	0.000	0.000
Cu	0.02669 (16)	0.03787 (18)	0.03043 (19)	0.00129 (12)	−0.00094 (12)	0.00159 (13)
Cl	0.0223 (3)	0.0601 (4)	0.0255 (3)	0.0057 (3)	−0.0008 (2)	0.0018 (3)
S	0.0265 (6)	0.0466 (8)	0.0312 (7)	−0.0018 (6)	−0.0029 (5)	0.0142 (6)
S'	0.0300 (6)	0.0342 (7)	0.0282 (7)	−0.0015 (5)	0.0020 (5)	−0.0081 (5)
N1	0.0257 (12)	0.0257 (12)	0.022 (2)	0.000	0.000	0.000
C1	0.0313 (13)	0.0255 (12)	0.0237 (12)	0.0002 (10)	0.0058 (10)	0.0007 (9)
C2	0.0307 (13)	0.0293 (13)	0.0315 (13)	−0.0016 (10)	0.0059 (11)	−0.0007 (10)
C3	0.0411 (16)	0.0377 (15)	0.0455 (17)	−0.0035 (12)	0.0152 (13)	0.0033 (13)
C4	0.0389 (17)	0.0444 (18)	0.086 (3)	−0.0099 (14)	0.0175 (17)	0.0001 (17)
N2	0.0264 (12)	0.0264 (12)	0.025 (2)	0.000	0.000	0.000
C5	0.0323 (13)	0.0295 (13)	0.0253 (12)	−0.0034 (10)	−0.0044 (10)	−0.0005 (10)
C6	0.0394 (16)	0.0470 (17)	0.0365 (15)	−0.0120 (13)	−0.0088 (12)	0.0086 (13)
C7	0.0456 (17)	0.0401 (16)	0.0462 (18)	−0.0150 (13)	−0.0113 (14)	0.0040 (13)
C8	0.0447 (17)	0.060 (2)	0.050 (2)	−0.0091 (15)	−0.0096 (14)	0.0067 (16)

Geometric parameters (Å, º) top

W—Cu	2.6404 (3)	C2—H2A	0.990
W—Cuⁱ	2.6404 (3)	C2—H2B	0.990
W—Cuⁱⁱ	2.6404 (3)	C2—C3	1.532 (4)
W—Cuⁱⁱⁱ	2.6404 (3)	C3—H3A	0.990
W—S	2.2435 (13)	C3—H3B	0.990
W—Sⁱ	2.2435 (13)	C3—C4	1.514 (4)
W—Sⁱⁱⁱ	2.2435 (13)	C4—H4A	0.980
W—Sⁱⁱ	2.2435 (13)	C4—H4B	0.980
W—S'	2.2555 (13)	C4—H4C	0.980
W—S'ⁱⁱ	2.2555 (13)	N2—C5	1.525 (2)
W—S'ⁱ	2.2555 (13)	N2—C5^iv	1.525 (2)
W—S'ⁱⁱⁱ	2.2555 (13)	N2—C5^vii	1.525 (2)
Cu—Cl	2.1586 (7)	N2—C5^viii	1.525 (2)
Cu—S	2.2302 (13)	C5—H5A	0.990
Cu—Sⁱ	2.2296 (14)	C5—H5B	0.990
Cu—S'	2.2882 (13)	C5—C6	1.519 (4)
Cu—S'ⁱ	2.2961 (13)	C6—H6A	0.990
S—Cuⁱⁱ	2.2296 (14)	C6—H6B	0.990
S'—Cuⁱⁱ	2.2962 (13)	C6—C7	1.537 (4)
N1—C1	1.521 (2)	C7—H7A	0.990
N1—C1^iv	1.521 (2)	C7—H7B	0.990
N1—C1^v	1.521 (2)	C7—C8	1.510 (4)
N1—C1^vi	1.521 (2)	C8—H8A	0.980
C1—H1A	0.990	C8—H8B	0.980
C1—H1B	0.990	C8—H8C	0.980
C1—C2	1.516 (4)

S—W—Sⁱⁱⁱ	109.61 (8)	C2—C3—H3A	109.0
Sⁱ—W—Sⁱⁱ	109.61 (8)	C2—C3—H3B	109.0
S—W—S'ⁱⁱ	108.63 (5)	C2—C3—C4	113.0 (3)
Sⁱⁱⁱ—W—S'ⁱⁱ	108.86 (5)	H3A—C3—H3B	107.8
Sⁱ—W—S'	108.63 (5)	H3A—C3—C4	109.0
Sⁱⁱ—W—S'	108.86 (5)	H3B—C3—C4	109.0
S—W—S'ⁱ	108.86 (5)	C3—C4—H4A	109.5
Sⁱⁱⁱ—W—S'ⁱ	108.63 (5)	C3—C4—H4B	109.5
Sⁱ—W—S'ⁱⁱⁱ	108.86 (5)	C3—C4—H4C	109.5
Sⁱⁱ—W—S'ⁱⁱⁱ	108.63 (5)	H4A—C4—H4B	109.5
S'ⁱⁱ—W—S'ⁱ	112.23 (7)	H4A—C4—H4C	109.5
S'—W—S'ⁱⁱⁱ	112.23 (7)	H4B—C4—H4C	109.5
Cl—Cu—S	124.08 (4)	C5—N2—C5^iv	104.99 (19)
Cl—Cu—Sⁱ	124.19 (4)	C5—N2—C5^vii	111.76 (10)
Cl—Cu—S'	127.81 (4)	C5^iv—N2—C5^vii	111.76 (10)
Cl—Cu—S'ⁱ	128.00 (4)	C5—N2—C5^viii	111.76 (10)
Sⁱ—Cu—S'	107.96 (5)	C5^iv—N2—C5^viii	111.76 (10)
S—Cu—S'ⁱ	107.89 (5)	C5^vii—N2—C5^viii	104.99 (19)
W—S—Cu	72.34 (4)	N2—C5—H5A	108.3
W—S—Cuⁱⁱ	72.35 (4)	N2—C5—H5B	108.3
Cu—S—Cuⁱⁱ	113.64 (6)	N2—C5—C6	116.0 (2)
W—S'—Cu	71.05 (4)	H5A—C5—H5B	107.4
W—S'—Cuⁱⁱ	70.91 (4)	H5A—C5—C6	108.3
Cu—S'—Cuⁱⁱ	109.02 (6)	H5B—C5—C6	108.3
C1^iv—N1—C1^v	111.83 (10)	C5—C6—H6A	109.7
C1^iv—N1—C1^vi	111.83 (10)	C5—C6—H6B	109.7
C1^v—N1—C1^vi	104.86 (19)	C5—C6—C7	110.0 (2)
C1—N1—C1^iv	104.86 (19)	H6A—C6—H6B	108.2
C1—N1—C1^v	111.83 (10)	H6A—C6—C7	109.7
C1—N1—C1^vi	111.83 (10)	H6B—C6—C7	109.7
N1—C1—H1A	108.0	C6—C7—H7A	108.8
N1—C1—H1B	108.0	C6—C7—H7B	108.8
N1—C1—C2	117.36 (19)	C6—C7—C8	113.9 (3)
H1A—C1—H1B	107.2	H7A—C7—H7B	107.7
H1A—C1—C2	108.0	H7A—C7—C8	108.8
H1B—C1—C2	108.0	H7B—C7—C8	108.8
C1—C2—H2A	110.0	C7—C8—H8A	109.5
C1—C2—H2B	110.0	C7—C8—H8B	109.5
C1—C2—C3	108.3 (2)	C7—C8—H8C	109.5
H2A—C2—H2B	108.4	H8A—C8—H8B	109.5
H2A—C2—C3	110.0	H8A—C8—H8C	109.5
H2B—C2—C3	110.0	H8B—C8—H8C	109.5

C1^iv—N1—C1—C2	−175.3 (2)	C5^iv—N2—C5—C6	−176.7 (3)
C1^v—N1—C1—C2	63.3 (3)	C5^vii—N2—C5—C6	62.0 (3)
C1^vi—N1—C1—C2	−54.0 (3)	C5^viii—N2—C5—C6	−55.4 (3)
N1—C1—C2—C3	−174.12 (19)	N2—C5—C6—C7	−173.2 (2)
C1—C2—C3—C4	−172.5 (2)	C5—C6—C7—C8	74.5 (3)

Symmetry codes: (i) −y+1/2, x, z; (ii) y, −x+1/2, z; (iii) −x+1/2, −y+1/2, z; (iv) −x+3/2, −y+1/2, z; (v) −y+1, x−1/2, −z; (vi) y+1/2, −x+1, −z; (vii) y+1/2, −x+1, −z+1; (viii) −y+1, x−1/2, −z+1.

Acknowledgements

We thank the EPSRC (UK) and the Research Office of Azarbaijan University for financial support.

References

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Volume 60| Part 12| December 2004| Pages m1952-m1954

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