(5E)-2-[4,5-Bis(methyl­sulfan­yl)-1,3-dithiol-2-yl­idene]-5-(4-iodo-1,3-dithiol-2-yl­idene)-1,3-dithio­lan-4-one

Ueda, K.; Yoza, K.

doi:10.1107/S1600536809044493

organic compounds

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ISSN: 2056-9890

Volume 65| Part 11| November 2009| Page o2920

https://doi.org/10.1107/S1600536809044493

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(5E)-2-[4,5-Bis(methylsulfanyl)-1,3-dithiol-2-ylidene]-5-(4-iodo-1,3-dithiol-2-ylidene)-1,3-dithiolan-4-one

Kazumasa Ueda ^a ^* and Kenji Yoza ^b

^aDivision of Applied Science and Fundamental Engineering, Faculty of Engineering, Shizuoka University, Johoku 3-5-1, Hamamatsu, Shizuoka, 432-8561, Japan, and ^bBruker AXS Co Ltd, Moriya-cho 3-9, Kanagawa-ku, Kanagawa, Kanagawa 221-0022, Japan
^*Correspondence e-mail: tkueda@ipc.shizuoka.ac.jp

(Received 19 October 2009; accepted 26 October 2009; online 31 October 2009)

The molecular framework of the title compound, C₁₁H₇IOS₈, is almost planar [maximum deviation = 0.040 (4) Å], except for the two methylsulfanyl groups, which are twisted relative to the molecular skeleton, making C—S—C—C torsion angles of 144.1 (8) and −141.3 (8)°. In the crystal, molecules are stacked alternately in opposite orientations, forming a one-dimensional column parallel to [110]. The primary interactions between molecules comprising the columns are of the S⋯S type [3.554 (1) Å]. Interactions between columns are of the S⋯S type [3.411 (1) along b and 3.444 (1) Å along c], as well as S⋯I contacts [3.435 (2) Å].

Related literature

For background to 2,5-di(1,3-dithiole-2-ylidene)-1,3-dithiolan-4-one derivatives, see: Iwamatsu et al. (1999 ); Matsumoto et al. (2002 , 2003 ); Hiraoka et al. (2007 ); Ueda & Yoza (2009 ). For the synthesis, see: Ueda & Yoza (2009). For background to intermolecular S⋯I contacts, see: Blake et al. (1997 , 1998 , 1999 ); Bricklebank et al. (2000 ); Ouvrard et al. (2003 ). For van der Waals radii, see: Bondi (1964 ).

Experimental

Crystal data

C₁₁H₇IOS₈
M_r = 538.55
Triclinic, $[P \overline 1]$
a = 8.309 (3) Å
b = 8.344 (3) Å
c = 14.618 (7) Å
α = 90.851 (6)°
β = 105.132 (6)°
γ = 118.510 (4)°
V = 848.0 (6) Å³
Z = 2
Mo Kα radiation
μ = 2.87 mm⁻¹
T = 93 K
0.04 × 0.04 × 0.04 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.894, T_max = 0.894
9773 measured reflections
3820 independent reflections
3065 reflections with I > 2σ(I)
R_int = 0.050

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.161
S = 1.07
3820 reflections
190 parameters
H-atom parameters constrained
Δρ_max = 2.34 e Å⁻³
Δρ_min = −1.13 e Å⁻³

Data collection: APEX2 (Bruker, 2006 ); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008 ); software used to prepare material for publication: XCIF (Bruker, 2001 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536809044493/tk2559sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536809044493/tk2559Isup2.hkl

checkCIF report

Comment top

2,5-Di(1,3-dithiol-2-ylidene)-1,3-dithiolan-4-one derivatives are used for the preparation of charge transfer salts with magnetic metal anions (Iwamatsu et al., 1999; Matsumoto et al., 2002a, b, 2003; Hiraoka et al., 2007). In CT salts these molecules can form unique crystal structures containing channels in addition to the usual stacked layer structures. The control of donor molecule interactions by means of chemical modification of the 2,5-di(1,3-dithiol-2-ylidene)-1,3-dithiolan-4-one skeleton may increase the dimensionality of aggregation in the solid-state. In this context, we have previously synthesized a molecule substituted with two iodide atoms, namely 2-[4,5-bis(methylsulfanyl)-1,3-dithiol-2-ylidene]-5-(4,5-diiodo-1,3-dithiol- 2-ylidene)-1,3-dithiolan-4-one, and observed fairly close I···O interactions in the crystal (Ueda & Yoza, 2009). As a continuation of these studies, herein, we present the crystal structure of a molecule substituted with one iodide atom, (I).

The molecular framework of (I), Fig. 1, except for two methylsulfanyl groups, is almost planar. The displacements of atoms S6, S9, and I1 relative to the plane of the skeleton are 0.106 (4), 0.236 (5) and 0.013 (4) Å, respectively. The torsion angles of the two methylsulfanyl groups are 144.1 (8)° for C10—S6—C8—C9 and -141.3 (8)° for C11—S9—C9—C8.

In the crystal structure, the molecules are stacked alternately in opposite orientations, forming a one-dimensional column parallel to the [110] direction (Fig. 2). The weak interactions between stacked molecules is accomplished through S···S contacts [S4···S6ⁱ = 3.554 (1) Å; symmetry code (i): 2-x, 2-y, 2-z] which are shorter than the sum of van der Waals radii of two S atoms, i.e. 3.60 Å (Bondi, 1964). It is noted that although the stacked molecules are separated by interplanar distances as short as 3.54 Å, they have fairly poor overlap. Some effective side-by-side contacts are observed between molecules of adjacent columns. These interactions are accomplished through S···S contacts [S2···S5ⁱⁱ = 3.411 (1) Å; symmetry code (ii): x, 1 + y, z] along the b axis. Stability along the c axis are afforded by additional S···S contacts [S9···S9ⁱⁱⁱ = 3.444 (1) Å; symmetry code (iii): 2 - x, 2 - y, 1 - z] as well as S···I contacts [S6···I1^iv = 3.435 (2) Å; symmetry code (iv): x, 1 + y, -1 + z]. This latter distance is shorter than the sum of corresponding van der Waals radii for S and I, i.e. 3.78 Å (Bondi, 1964). Such S···I interactions have been observed previously (Blake et al., 1997, 1998, 1999; Bricklebank et al., 2000). The intermolecular angles, 162.8 (2)° for S6···I1^iv—C1^iv and 105.8 (4)° for C10—S6···I1^iv, are close to the ideal geometry (180° for C—I···S and 109.5° for C—S···I) which have been proposed for these types of associations (Ouvrard et al., 2003).

Related literature top

For background to 2,5-di(1,3-dithiole-2-ylidene)-1,3-dithiolan-4-one derivatives, see: Iwamatsu et al. (1999); Matsumoto et al. (2002, 2003); Hiraoka et al. (2007); Ueda & Yoza (2009). For the synthesis, see: Ueda & Yoza (2009). For background to intermolecular S···I contacts, see: Blake et al. (1997, 1998, 1999); Bricklebank et al. (2000); Ouvrard et al. (2003). For van der Waals radii, see: Bondi (1964).

Experimental top

Compound (I) was synthesized by a modification of the method used for the preparation of 2-[4,5-bis(methylsulfanyl)-1,3-dithiol-2-ylidene]-5-(4,5-diiodo-1,3-dithiol- 2-ylidene)-1,3-dithiolan-4-one (Ueda & Yoza, 2009). Bis(tetramethylammonium)bis[2-[4,5-bis(methylsulfanyl)-1,3-dithiol-2- ylidene]-1,3-dithiole-4,5-bis(thiolato)]zinc (402.4 mg, 0.4322 mmol) was reacted with 4-iodo-2-methylsulfanyl-1,3-dithiole-2-ylium tetrafluoroborate (457.5 mg, 1.2639 mmol) in THF-DMF (5:1 = v/v) at room temperature under nitrogen. Stirring was carried out for 12 h. After separation of the reaction mixture by column chromatography on silica gel (eluent CS₂) followed by recrystallization from CS₂/hexane, (5E)-2-[4,5-bis(methylsulfanyl)-1,3-dithiole-2-ylidene]-5-(4-iodo- 1,3-dithiole-2-ylidene)-1,3-dithiolan-4-thione (II) was obtained as dark-green needles in 74% yield.

When compound (II) (151.6 mg, 0.2733 mmol) was reacted with mercury(II) acetate (191.6 mg, 0.6012 mmol) in THF-AcOH (50:1 = v/v), compound (I) was obtained as dark-red platelets in 58% yield by recrystallization from CS₂/hexane.

Structure description top

For background to 2,5-di(1,3-dithiole-2-ylidene)-1,3-dithiolan-4-one derivatives, see: Iwamatsu et al. (1999); Matsumoto et al. (2002, 2003); Hiraoka et al. (2007); Ueda & Yoza (2009). For the synthesis, see: Ueda & Yoza (2009). For background to intermolecular S···I contacts, see: Blake et al. (1997, 1998, 1999); Bricklebank et al. (2000); Ouvrard et al. (2003). For van der Waals radii, see: Bondi (1964).

Computing details top

Data collection: APEX2 (Bruker, 2006); cell refinement: APEX2 (Bruker, 2006); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: XCIF (Bruker, 2001).

Figures top

	Fig. 1. The molecular structure of (I) showing atom labeling and 50% probability of displacement ellipsoids for non H-atoms.
	Fig. 2. Projection of the crystal packing in (I) along the [110] direction. The S···S (gray), and S···I (blue) contacts are shown with dashed lines. H atoms are omitted for clarity.
	Fig. 3. Projection of the crystal packing in (I) along the longer molecular axis. The S···S contacts are shown with gray dashed lines. H atoms are omitted for clarity.

(5E)-2-[4,5-Bis(methylsulfanyl)-1,3-dithiol-2-ylidene]-5-(4-iodo-1,3- dithiol-2-ylidene)-1,3-dithiolan-4-one top

Crystal data top

C₁₁H₇IOS₈	Z = 2
M_r = 538.55	F(000) = 524
Triclinic, P1	D_x = 2.109 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.309 (3) Å	Cell parameters from 2153 reflections
b = 8.344 (3) Å	θ = 2.8–25.3°
c = 14.618 (7) Å	µ = 2.87 mm⁻¹
α = 90.851 (6)°	T = 93 K
β = 105.132 (6)°	Block, dark-red
γ = 118.510 (4)°	0.04 × 0.04 × 0.04 mm
V = 848.0 (6) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	3820 independent reflections
Radiation source: Bruker TXS fine-focus rotating anode	3065 reflections with I > 2σ(I)
Bruker Helios multilayer confocal mirror monochromator	R_int = 0.050
Detector resolution: 8.333 pixels mm^-1	θ_max = 27.5°, θ_min = 1.5°
φ and ω scans	h = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −10→10
T_min = 0.894, T_max = 0.894	l = −18→18
9773 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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.161	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0842P)² + 3.4063P] where P = (F_o² + 2F_c²)/3
3820 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 2.34 e Å⁻³
0 restraints	Δρ_min = −1.13 e Å⁻³

Crystal data top

C₁₁H₇IOS₈	γ = 118.510 (4)°
M_r = 538.55	V = 848.0 (6) Å³
Triclinic, P1	Z = 2
a = 8.309 (3) Å	Mo Kα radiation
b = 8.344 (3) Å	µ = 2.87 mm⁻¹
c = 14.618 (7) Å	T = 93 K
α = 90.851 (6)°	0.04 × 0.04 × 0.04 mm
β = 105.132 (6)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3820 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3065 reflections with I > 2σ(I)
T_min = 0.894, T_max = 0.894	R_int = 0.050
9773 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.161	H-atom parameters constrained
S = 1.07	Δρ_max = 2.34 e Å⁻³
3820 reflections	Δρ_min = −1.13 e Å⁻³
190 parameters

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
C1	0.7414 (11)	0.3494 (11)	1.2804 (5)	0.0208 (15)
C2	0.7832 (11)	0.2717 (10)	1.2163 (5)	0.0200 (15)
H2A	0.7957	0.1652	1.2252	0.024*
C3	0.7600 (10)	0.5445 (10)	1.1458 (5)	0.0171 (14)
C4	0.7523 (10)	0.6656 (10)	1.0854 (5)	0.0147 (14)
C5	0.7096 (11)	0.8045 (10)	1.1130 (5)	0.0176 (15)
C6	0.7518 (10)	0.8433 (10)	0.9411 (5)	0.0188 (15)
C7	0.7691 (10)	0.9104 (10)	0.8586 (5)	0.0168 (14)
C8	0.7811 (11)	1.1023 (10)	0.7195 (5)	0.0195 (15)
C9	0.8259 (11)	0.9774 (10)	0.6922 (6)	0.0227 (16)
C10	0.5811 (14)	1.2907 (13)	0.6735 (8)	0.040 (2)
H10A	0.5663	1.3860	0.6401	0.060*
H10B	0.6051	1.3221	0.7424	0.060*
H10C	0.4633	1.1708	0.6481	0.060*
C11	0.7773 (12)	0.7290 (12)	0.5471 (7)	0.0317 (19)
H11A	0.8072	0.7093	0.4888	0.048*
H11B	0.6381	0.6763	0.5324	0.048*
H11C	0.8218	0.6686	0.5964	0.048*
I1	0.72165 (7)	0.26967 (7)	1.41327 (4)	0.02158 (17)
O1	0.6819 (8)	0.8263 (7)	1.1898 (4)	0.0248 (12)
S2	0.6928 (3)	0.9427 (3)	1.02369 (13)	0.0204 (4)
S3	0.7856 (3)	0.6574 (3)	0.97138 (13)	0.0192 (4)
S4	0.7150 (3)	0.5414 (2)	1.25643 (13)	0.0180 (4)
S5	0.8134 (3)	0.3773 (3)	1.11542 (14)	0.0223 (4)
S6	0.7799 (3)	1.2779 (3)	0.65508 (14)	0.0222 (4)
S7	0.8283 (3)	0.8205 (3)	0.77148 (14)	0.0215 (4)
S8	0.7337 (3)	1.0982 (3)	0.83040 (14)	0.0212 (4)
S9	0.8974 (4)	0.9749 (3)	0.59090 (16)	0.0318 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.018 (4)	0.025 (4)	0.019 (4)	0.011 (3)	0.004 (3)	0.005 (3)
C2	0.029 (4)	0.017 (4)	0.018 (4)	0.015 (3)	0.008 (3)	0.006 (3)
C3	0.014 (3)	0.015 (3)	0.021 (4)	0.005 (3)	0.006 (3)	0.001 (3)
C4	0.018 (3)	0.014 (3)	0.016 (3)	0.010 (3)	0.006 (3)	0.004 (3)
C5	0.021 (4)	0.021 (4)	0.014 (3)	0.011 (3)	0.007 (3)	0.004 (3)
C6	0.019 (4)	0.020 (4)	0.018 (4)	0.010 (3)	0.006 (3)	0.003 (3)
C7	0.017 (3)	0.017 (4)	0.014 (3)	0.007 (3)	0.005 (3)	0.002 (3)
C8	0.022 (4)	0.021 (4)	0.014 (4)	0.008 (3)	0.010 (3)	0.005 (3)
C9	0.024 (4)	0.016 (4)	0.027 (4)	0.005 (3)	0.014 (3)	0.007 (3)
C10	0.045 (6)	0.035 (5)	0.062 (7)	0.028 (5)	0.032 (5)	0.027 (5)
C11	0.030 (4)	0.026 (4)	0.038 (5)	0.010 (4)	0.016 (4)	0.002 (4)
I1	0.0234 (3)	0.0216 (3)	0.0216 (3)	0.0115 (2)	0.0088 (2)	0.00788 (19)
O1	0.034 (3)	0.022 (3)	0.026 (3)	0.017 (3)	0.014 (3)	0.010 (2)
S2	0.0297 (10)	0.0244 (10)	0.0164 (9)	0.0194 (8)	0.0092 (8)	0.0063 (7)
S3	0.0267 (10)	0.0213 (9)	0.0160 (9)	0.0154 (8)	0.0094 (8)	0.0053 (7)
S4	0.0220 (9)	0.0180 (9)	0.0191 (9)	0.0113 (7)	0.0111 (7)	0.0063 (7)
S5	0.0311 (10)	0.0206 (9)	0.0213 (10)	0.0160 (8)	0.0110 (8)	0.0041 (7)
S6	0.0270 (10)	0.0246 (10)	0.0191 (9)	0.0134 (8)	0.0119 (8)	0.0101 (7)
S7	0.0282 (10)	0.0221 (9)	0.0194 (9)	0.0145 (8)	0.0113 (8)	0.0048 (7)
S8	0.0267 (10)	0.0261 (10)	0.0185 (9)	0.0169 (8)	0.0109 (8)	0.0084 (7)
S9	0.0504 (13)	0.0232 (10)	0.0270 (11)	0.0150 (10)	0.0265 (10)	0.0058 (8)

Geometric parameters (Å, º) top

C1—C2	1.337 (11)	C7—S7	1.755 (7)
C1—S4	1.746 (8)	C7—S8	1.762 (8)
C1—I1	2.083 (8)	C8—C9	1.349 (11)
C2—S5	1.741 (8)	C8—S6	1.755 (8)
C2—H2A	0.9500	C8—S8	1.763 (7)
C3—C4	1.365 (10)	C9—S9	1.736 (8)
C3—S5	1.737 (7)	C9—S7	1.765 (8)
C3—S4	1.751 (8)	C10—S6	1.792 (9)
C4—C5	1.444 (10)	C10—H10A	0.9800
C4—S3	1.764 (7)	C10—H10B	0.9800
C5—O1	1.230 (9)	C10—H10C	0.9800
C5—S2	1.777 (8)	C11—S9	1.813 (9)
C6—C7	1.350 (10)	C11—H11A	0.9800
C6—S2	1.747 (8)	C11—H11B	0.9800
C6—S3	1.747 (8)	C11—H11C	0.9800

C2—C1—S4	118.7 (6)	C8—C9—S9	124.2 (6)
C2—C1—I1	124.9 (6)	C8—C9—S7	116.2 (6)
S4—C1—I1	116.2 (4)	S9—C9—S7	119.4 (5)
C1—C2—S5	116.1 (6)	S6—C10—H10A	109.5
C1—C2—H2A	122.0	S6—C10—H10B	109.5
S5—C2—H2A	122.0	H10A—C10—H10B	109.5
C4—C3—S5	121.0 (6)	S6—C10—H10C	109.5
C4—C3—S4	124.0 (6)	H10A—C10—H10C	109.5
S5—C3—S4	115.1 (4)	H10B—C10—H10C	109.5
C3—C4—C5	119.7 (7)	S9—C11—H11A	109.5
C3—C4—S3	122.9 (6)	S9—C11—H11B	109.5
C5—C4—S3	117.3 (5)	H11A—C11—H11B	109.5
O1—C5—C4	124.7 (7)	S9—C11—H11C	109.5
O1—C5—S2	121.3 (6)	H11A—C11—H11C	109.5
C4—C5—S2	113.9 (5)	H11B—C11—H11C	109.5
C7—C6—S2	120.1 (6)	C6—S2—C5	96.5 (4)
C7—C6—S3	123.1 (6)	C6—S3—C4	95.3 (3)
S2—C6—S3	116.8 (4)	C1—S4—C3	94.2 (4)
C6—C7—S7	123.5 (6)	C3—S5—C2	95.8 (4)
C6—C7—S8	121.9 (6)	C8—S6—C10	102.2 (4)
S7—C7—S8	114.6 (4)	C7—S7—C9	96.0 (4)
C9—C8—S6	124.3 (6)	C7—S8—C8	95.1 (4)
C9—C8—S8	118.1 (6)	C9—S9—C11	101.7 (4)
S6—C8—S8	117.4 (4)

Experimental details

Crystal data
Chemical formula	C₁₁H₇IOS₈
M_r	538.55
Crystal system, space group	Triclinic, P1
Temperature (K)	93
a, b, c (Å)	8.309 (3), 8.344 (3), 14.618 (7)
α, β, γ (°)	90.851 (6), 105.132 (6), 118.510 (4)
V (Å³)	848.0 (6)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.87
Crystal size (mm)	0.04 × 0.04 × 0.04

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.894, 0.894
No. of measured, independent and observed [I > 2σ(I)] reflections	9773, 3820, 3065
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.161, 1.07
No. of reflections	3820
No. of parameters	190
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.34, −1.13

Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), Mercury (Macrae et al., 2008), XCIF (Bruker, 2001).

Acknowledgements

This work was supported by the Hamashin Regional Development Foundation and the Japan Chemical Innovation Institute.

References

Blake, A. J., Cristiani, F., Devillanova, F. A., Garau, A., Gilby, L. M., Gould, R. O., Isaia, F., Lippolis, V., Parsons, S., Radek, C. & Schröder, M. (1997). J. Chem. Soc. Dalton Trans. pp. 1337–1346. CSD CrossRef Web of Science Google Scholar
Blake, A. J., Devillanova, F. A., Garau, A., Gilby, L. M., Gould, R. O., Isaia, F., Lippolis, V., Parsons, S., Radek, C. & Schröder, M. (1998). J. Chem. Soc. Dalton Trans. pp. 2037–2046. Web of Science CSD CrossRef Google Scholar
Blake, A. J., Devillanova, F. A., Garau, A., Isaia, F., Lippolis, V., Parsons, S. & Schröder, M. (1999). J. Chem. Soc. Dalton Trans. pp. 525–531. Web of Science CSD CrossRef Google Scholar
Bondi, A. (1964). J. Phys. Chem. 68, 441–451. CrossRef CAS Web of Science Google Scholar
Bricklebank, N., Hargreaves, S. & Spey, S. E. (2000). Polyhedron, 19, 1163–1166. Web of Science CSD CrossRef CAS Google Scholar
Bruker (2001). XCIF. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2004). SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Bruker (2006). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Hiraoka, T., Fujiwara, H., Sugimoto, T., Nakazumi, H., Noguchi, S., Kuribayashi, A., Ishida, T., Yokogawa, K., Murata, K., Mori, T., Aruga-Katori, H., Kimura, S. & Hagiwara, M. (2007). J. Mater. Chem. 17, 1664–1673. Web of Science CSD CrossRef CAS Google Scholar
Iwamatsu, M., Kominami, T., Ueda, K., Sugimoto, T., Fujita, H. & Adachi, T. (1999). Chem. Lett. pp. 329–330. Google Scholar
Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466–470. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Matsumoto, T., Kamada, Y., Sugimoto, T., Tada, T., Nakazumi, H., Kawakami, T. & Yamaguchi, K. (2003). Synth. Met. 135–136, 575–576. Web of Science CSD CrossRef CAS Google Scholar
Matsumoto, T., Kominami, T., Ueda, K., Sugimoto, T., Tada, T., Noguchi, S., Yoshino, H., Murata, K., Shiro, M., Negishi, E., Toyota, N., Endo, S. & Takahashi, K. (2002). Inorg. Chem. 41, 4763–4769. Web of Science CSD CrossRef PubMed CAS Google Scholar
Ouvrard, C., Le Questel, J.-Y., Berthelot, M. & Laurence, C. (2003). Acta Cryst. B59, 512–526. Web of Science CrossRef CAS IUCr Journals Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Ueda, K. & Yoza, K. (2009). Acta Cryst. E65, o2716. Web of Science CrossRef IUCr Journals Google Scholar

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