Octa­carbon­yl(5-meth­oxy-2,3-dihydro-1H-benzimidazol-2-yl)di-μ3-sulfido-diiron(I)iron(II)(2 Fe—Fe)

Zhang, T.; Wang, M.; Li, P.; Sun, L.

doi:10.1107/S160053680706415X

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 1| January 2008| Page m217

https://doi.org/10.1107/S160053680706415X

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Octacarbonyl(5-methoxy-2,3-dihydro-1H-benzimidazol-2-yl)di-μ₃-sulfido-diiron(I)iron(II)(2 Fe—Fe)

Tingting Zhang,^a Mei Wang,^a ^* Ping Li ^a and Licheng Sun ^a ^*

^aState Key Laboratory of Fine Chemicals, DUT-KTH Joint Education and Research Centre on Molecular Devices, Dalian University of Technology, 158 Zhongshan Rd, Dalian 116012, People's Republic of China
^*Correspondence e-mail: symbueno@dlut.edu.cn, lichengs@kth.se

(Received 9 November 2007; accepted 28 November 2007; online 18 December 2007)

The title compound, [Fe₃(C₈H₈N₂O)S₂(CO)₈], was prepared by the direct reaction of Fe₃(CO)₁₂ and 5-methoxy-1H-benzoimidazole-2-thiol in tetrahydrofuran. Desulfurization took place readily to form a sulfide carbonyl cluster. The molecule contains a triangle consisting of three Fe atoms capped by two S atoms above and below. There are two Fe—Fe bonds [2.6322 (5) and 2.5582 (5) Å] in the triangle; the length of the third edge [3.3987 (5) Å] is too long to represent an Fe—Fe bond.

Related literature

For related literature, see: Adams & Wang (1985 ); Adams & Yang (1983 ); Bard et al. (1985 ); Benoit et al. (1982 ); Weininger & Stermitz (1984 ).

Experimental

Crystal data

[Fe₃(C₈H₈N₂O)S₂(CO)₈]
M_r = 603.91
Triclinic, $[P \overline 1]$
a = 9.0068 (4) Å
b = 11.4504 (5) Å
c = 12.5976 (6) Å
α = 112.332 (3)°
β = 108.728 (3)°
γ = 96.229 (3)°
V = 1098.0 (1) Å³
Z = 2
Mo Kα radiation
μ = 2.20 mm⁻¹
T = 273 (2) K
0.25 × 0.20 × 0.10 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1997 ) T_min = 0.610, T_max = 0.810
8226 measured reflections
4253 independent reflections
3584 reflections with I > 2σ(I)
R_int = 0.019

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.070
S = 1.05
4253 reflections
289 parameters
H-atom parameters constrained
Δρ_max = 0.28 e Å⁻³
Δρ_min = −0.30 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Fe2—S2	2.2505 (7)
Fe2—S1	2.2621 (7)
Fe2—Fe3	2.5582 (5)
Fe2—Fe1	2.6322 (5)
Fe1—C9	1.914 (2)
Fe1—S1	2.2294 (6)
Fe1—S2	2.2337 (7)
Fe3—S1	2.2415 (6)
Fe3—S2	2.2455 (6)

C9—Fe1—Fe2	138.68 (7)
C6—Fe3—Fe2	145.32 (10)
Fe1—S2—Fe3	98.71 (2)
Fe1—S2—Fe2	71.89 (2)
Fe3—S2—Fe2	69.362 (19)
Fe1—S1—Fe3	98.96 (2)
Fe1—S1—Fe2	71.75 (2)
Fe3—S1—Fe2	69.23 (2)

Data collection: APEX2 (Bruker, 2001 ); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S160053680706415X/hy2102sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680706415X/hy2102Isup2.hkl

checkCIF report

Comment top

The chemistry of sulfide carbonyl clusters is well developed not only on account of their fascinating structural chemistry, but also because of their ability to act as electron reservoirs and potential in catalysis (Adams & Wang, 1985; Adams & Yang, 1983). Here we report the crystal structure of the title compound.

The central Fe₃S₂ unit in the title compound is in accord with that for the well known complex [Fe₃(µ₃-S)₂(CO)₉] (Bard et al., 1985). The molecule contains a triangle of Fe atoms capped by two S atoms above and below. There exist two Fe—Fe bonds in the molecule, that is, Fe1—Fe2 [2.6322 (5) Å] and Fe2—Fe3 [2.5582 (5) Å] bonds, while the distance between Fe1 and Fe3 [3.3987 (5) Å] is too long to form a Fe—Fe bond. The Fe1—C9 bond length [1.914 (2) Å] is similar to that for another carbene–iron complex (Benoit et al., 1982). The distances of two C9—N bonds [1.348 (3) and 1.355 (3) Å] are significantly shorter than that of the C—N single bond (1.47 Å) (Weininger & Stermitz, 1984) and longer than that of the C—N double bond (1.30 Å) (Weininger & Stermitz, 1984). The sum of the angles around the C9 atom is 359.6°, suggesting an sp²-hybridized C atom.

Related literature top

For related literature, see: Adams & Wang (1985); Adams & Yang (1983); Bard et al. (1985); Benoit et al. (1982); Weininger & Stermitz (1984).

Experimental top

Fe₃(CO)₁₂ (0.50 g, 1 mmol) was added to a solution of 5-methoxy-1H-benzoimidazole-2-thiol (0.54 g, 3 mmol) in THF (20 ml). After the solution was refluxed for 20 min, the solvent was removed under reduced pressure and the residue was chromatographed on a silica gel column with CH₂Cl₂/hexane (2:1 v/v) as the eluent to give the title compound as a brown solid (yield 60%, 0.36 g). Single crystals of the title compound were obtained by slow evaporation of the CH₂Cl₂ solution at room temperature.

Structure description top

For related literature, see: Adams & Wang (1985); Adams & Yang (1983); Bard et al. (1985); Benoit et al. (1982); Weininger & Stermitz (1984).

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures top

Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level.

Octacarbonyl(5-methoxy-2,3-dihydro-1H-benzimidazol-2-yl)di-µ₃– sulfido-diiron(I)iron(II)(2 Fe—Fe) top

Crystal data top

[Fe₃(C₈H₈N₂O)S₂(CO)₈]	Z = 2
M_r = 603.91	F(000) = 600
Triclinic, P1	D_x = 1.827 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 9.0068 (4) Å	Cell parameters from 3399 reflections
b = 11.4504 (5) Å	θ = 3.6–29.3°
c = 12.5976 (6) Å	µ = 2.20 mm⁻¹
α = 112.332 (3)°	T = 273 K
β = 108.728 (3)°	Block, brown
γ = 96.229 (3)°	0.25 × 0.20 × 0.10 mm
V = 1098.0 (1) Å³

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4253 independent reflections
Radiation source: fine-focus sealed tube	3584 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.019
φ and ω scans	θ_max = 26.0°, θ_min = 3.6°
Absorption correction: multi-scan (SADABS; Bruker, 1997)	h = −11→10
T_min = 0.610, T_max = 0.810	k = −14→13
8226 measured reflections	l = −15→15

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.028	w = 1/[σ²(F_o²) + (0.0345P)² + 0.1529P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.070	(Δ/σ)_max = 0.001
S = 1.05	Δρ_max = 0.28 e Å⁻³
4253 reflections	Δρ_min = −0.30 e Å⁻³
289 parameters

Crystal data top

[Fe₃(C₈H₈N₂O)S₂(CO)₈]	γ = 96.229 (3)°
M_r = 603.91	V = 1098.0 (1) Å³
Triclinic, P1	Z = 2
a = 9.0068 (4) Å	Mo Kα radiation
b = 11.4504 (5) Å	µ = 2.20 mm⁻¹
c = 12.5976 (6) Å	T = 273 K
α = 112.332 (3)°	0.25 × 0.20 × 0.10 mm
β = 108.728 (3)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4253 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1997)	3584 reflections with I > 2σ(I)
T_min = 0.610, T_max = 0.810	R_int = 0.019
8226 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	0 restraints
wR(F²) = 0.070	H-atom parameters constrained
S = 1.05	Δρ_max = 0.28 e Å⁻³
4253 reflections	Δρ_min = −0.30 e Å⁻³
289 parameters

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

	x	y	z	U_iso*/U_eq
Fe2	0.76196 (4)	0.76148 (3)	0.59336 (3)	0.03973 (10)
Fe1	0.94423 (4)	1.00067 (3)	0.75013 (3)	0.03945 (10)
Fe3	0.54802 (4)	0.85600 (3)	0.66569 (3)	0.03970 (10)
S2	0.70315 (7)	0.94813 (6)	0.59519 (5)	0.03972 (14)
S1	0.79595 (7)	0.87177 (6)	0.79494 (5)	0.04141 (14)
N1	0.9696 (2)	1.2115 (2)	0.98758 (18)	0.0454 (5)
H1A	1.0240	1.1784	1.0333	0.055*
N2	0.8456 (2)	1.24400 (19)	0.83051 (17)	0.0439 (5)
H2A	0.8050	1.2356	0.7554	0.053*
C9	0.9253 (3)	1.1612 (2)	0.8629 (2)	0.0406 (5)
O8	0.2735 (2)	0.7602 (2)	0.4266 (2)	0.0715 (6)
O2	1.1025 (3)	1.1243 (2)	0.6350 (2)	0.0833 (7)
C15	0.8368 (3)	1.3437 (2)	0.9318 (2)	0.0413 (5)
C2	1.0438 (3)	1.0765 (3)	0.6799 (2)	0.0530 (6)
O1	1.2491 (3)	0.9921 (2)	0.9194 (2)	0.0819 (7)
C8	0.3784 (3)	0.7992 (2)	0.5209 (3)	0.0475 (6)
C1	1.1322 (3)	0.9977 (3)	0.8553 (2)	0.0524 (6)
C10	0.9171 (3)	1.3231 (2)	1.0340 (2)	0.0443 (5)
O5	0.5879 (3)	0.6474 (2)	0.3226 (2)	0.0884 (7)
C5	0.6572 (3)	0.6905 (3)	0.4274 (3)	0.0555 (6)
C4	0.7104 (3)	0.6124 (3)	0.6041 (3)	0.0607 (7)
O9	0.7147 (3)	1.63452 (19)	1.08295 (19)	0.0690 (5)
C14	0.7649 (3)	1.4461 (2)	0.9402 (2)	0.0479 (6)
H14A	0.7104	1.4583	0.8703	0.057*
O4	0.6759 (3)	0.5192 (2)	0.6127 (3)	0.0997 (9)
C13	0.7787 (3)	1.5292 (2)	1.0582 (2)	0.0514 (6)
O3	1.0797 (3)	0.7445 (3)	0.5882 (3)	0.1048 (9)
C3	0.9606 (4)	0.7601 (3)	0.5954 (3)	0.0638 (7)
C12	0.8608 (4)	1.5093 (3)	1.1619 (3)	0.0606 (7)
H12A	0.8691	1.5673	1.2402	0.073*
O7	0.3939 (3)	0.6703 (3)	0.7320 (3)	0.1099 (10)
O6	0.4779 (4)	1.0948 (3)	0.8090 (3)	0.1222 (11)
C16	0.6157 (4)	1.6512 (3)	0.9793 (3)	0.0694 (8)
H16A	0.5782	1.7280	1.0085	0.104*
H16B	0.5240	1.5760	0.9268	0.104*
H16C	0.6778	1.6608	0.9324	0.104*
C11	0.9296 (4)	1.4067 (3)	1.1513 (2)	0.0596 (7)
H11A	0.9830	1.3937	1.2208	0.072*
C6	0.5036 (4)	1.0008 (3)	0.7545 (3)	0.0670 (8)
C7	0.4532 (3)	0.7432 (3)	0.7076 (3)	0.0630 (8)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Fe2	0.03531 (18)	0.03891 (18)	0.0433 (2)	0.00916 (14)	0.01431 (15)	0.01758 (15)
Fe1	0.03450 (18)	0.04229 (19)	0.03923 (19)	0.00558 (14)	0.01320 (14)	0.01792 (15)
Fe3	0.03299 (17)	0.0493 (2)	0.04277 (19)	0.01194 (14)	0.01478 (15)	0.02601 (16)
S2	0.0417 (3)	0.0408 (3)	0.0379 (3)	0.0078 (2)	0.0127 (2)	0.0218 (2)
S1	0.0376 (3)	0.0511 (3)	0.0393 (3)	0.0103 (2)	0.0115 (2)	0.0271 (3)
N1	0.0463 (11)	0.0522 (12)	0.0390 (11)	0.0147 (9)	0.0118 (9)	0.0249 (9)
N2	0.0498 (12)	0.0459 (11)	0.0312 (10)	0.0135 (9)	0.0098 (9)	0.0171 (9)
C9	0.0366 (12)	0.0446 (13)	0.0386 (12)	0.0043 (10)	0.0107 (10)	0.0213 (10)
O8	0.0584 (12)	0.0816 (14)	0.0628 (13)	0.0070 (10)	−0.0016 (11)	0.0442 (11)
O2	0.0897 (16)	0.0868 (16)	0.0683 (14)	−0.0140 (12)	0.0409 (13)	0.0309 (12)
C15	0.0377 (12)	0.0419 (12)	0.0349 (12)	0.0033 (10)	0.0092 (10)	0.0135 (10)
C2	0.0492 (15)	0.0533 (15)	0.0424 (14)	−0.0003 (12)	0.0158 (12)	0.0124 (12)
O1	0.0495 (12)	0.1139 (19)	0.0762 (15)	0.0262 (12)	0.0098 (11)	0.0468 (14)
C8	0.0446 (14)	0.0504 (14)	0.0560 (16)	0.0122 (11)	0.0184 (13)	0.0333 (13)
C1	0.0425 (15)	0.0593 (16)	0.0506 (15)	0.0078 (12)	0.0174 (13)	0.0217 (13)
C10	0.0428 (13)	0.0506 (14)	0.0372 (12)	0.0095 (11)	0.0126 (10)	0.0203 (11)
O5	0.0985 (18)	0.0868 (16)	0.0450 (13)	0.0029 (13)	0.0138 (12)	0.0118 (11)
C5	0.0543 (16)	0.0519 (15)	0.0525 (17)	0.0100 (12)	0.0205 (14)	0.0167 (13)
C4	0.0521 (16)	0.0481 (15)	0.0701 (19)	0.0088 (12)	0.0095 (14)	0.0274 (14)
O9	0.0762 (14)	0.0546 (11)	0.0598 (12)	0.0263 (10)	0.0217 (11)	0.0107 (9)
C14	0.0471 (14)	0.0452 (13)	0.0421 (13)	0.0096 (11)	0.0092 (11)	0.0176 (11)
O4	0.0993 (18)	0.0560 (14)	0.126 (2)	0.0023 (13)	0.0133 (16)	0.0536 (14)
C13	0.0447 (14)	0.0470 (14)	0.0486 (15)	0.0058 (11)	0.0152 (12)	0.0115 (11)
O3	0.0574 (14)	0.115 (2)	0.134 (2)	0.0314 (14)	0.0518 (15)	0.0326 (18)
C3	0.0474 (16)	0.0646 (18)	0.074 (2)	0.0155 (13)	0.0261 (15)	0.0226 (15)
C12	0.0632 (18)	0.0668 (18)	0.0396 (14)	0.0169 (14)	0.0187 (13)	0.0125 (13)
O7	0.0737 (15)	0.156 (3)	0.152 (3)	0.0164 (16)	0.0421 (17)	0.125 (2)
O6	0.127 (2)	0.0838 (19)	0.156 (3)	0.0416 (17)	0.096 (2)	0.0157 (18)
C16	0.0660 (19)	0.0555 (17)	0.076 (2)	0.0228 (14)	0.0210 (17)	0.0227 (15)
C11	0.0653 (18)	0.0754 (19)	0.0356 (13)	0.0216 (15)	0.0157 (13)	0.0245 (13)
C6	0.0574 (17)	0.070 (2)	0.075 (2)	0.0180 (15)	0.0374 (16)	0.0234 (16)
C7	0.0397 (14)	0.095 (2)	0.0701 (19)	0.0154 (14)	0.0162 (13)	0.0568 (18)

Geometric parameters (Å, º) top

Fe2—C3	1.783 (3)	O8—C8	1.135 (3)
Fe2—C4	1.787 (3)	O2—C2	1.125 (3)
Fe2—C5	1.788 (3)	C15—C10	1.380 (3)
Fe2—S2	2.2505 (7)	C15—C14	1.386 (3)
Fe2—S1	2.2621 (7)	O1—C1	1.128 (3)
Fe2—Fe3	2.5582 (5)	C10—C11	1.381 (4)
Fe2—Fe1	2.6322 (5)	O5—C5	1.134 (3)
Fe1—C1	1.797 (3)	C4—O4	1.133 (3)
Fe1—C2	1.807 (3)	O9—C13	1.366 (3)
Fe1—C9	1.914 (2)	O9—C16	1.420 (3)
Fe1—S1	2.2294 (6)	C14—C13	1.383 (4)
Fe1—S2	2.2337 (7)	C14—H14A	0.9300
Fe3—C8	1.783 (3)	C13—C12	1.395 (4)
Fe3—C6	1.784 (3)	O3—C3	1.133 (3)
Fe3—C7	1.801 (3)	C12—C11	1.369 (4)
Fe3—S1	2.2415 (6)	C12—H12A	0.9300
Fe3—S2	2.2455 (6)	O7—C7	1.132 (3)
N1—C9	1.348 (3)	O6—C6	1.130 (4)
N1—C10	1.392 (3)	C16—H16A	0.9600
N1—H1A	0.8600	C16—H16B	0.9600
N2—C9	1.355 (3)	C16—H16C	0.9600
N2—C15	1.384 (3)	C11—H11A	0.9300
N2—H2A	0.8600

C3—Fe2—C4	99.51 (14)	S2—Fe3—Fe2	55.410 (18)
C3—Fe2—C5	96.64 (14)	Fe1—S2—Fe3	98.71 (2)
C4—Fe2—C5	94.66 (13)	Fe1—S2—Fe2	71.89 (2)
C3—Fe2—S2	110.82 (10)	Fe3—S2—Fe2	69.362 (19)
C4—Fe2—S2	149.33 (10)	Fe1—S1—Fe3	98.96 (2)
C5—Fe2—S2	86.53 (9)	Fe1—S1—Fe2	71.75 (2)
C3—Fe2—S1	105.97 (10)	Fe3—S1—Fe2	69.23 (2)
C4—Fe2—S1	88.38 (10)	C9—N1—C10	112.33 (19)
C5—Fe2—S1	156.38 (9)	C9—N1—H1A	123.8
S2—Fe2—S1	79.21 (2)	C10—N1—H1A	123.8
C3—Fe2—Fe3	156.00 (10)	C9—N2—C15	112.47 (19)
C4—Fe2—Fe3	94.73 (10)	C9—N2—H2A	123.8
C5—Fe2—Fe3	101.37 (9)	C15—N2—H2A	123.8
S2—Fe2—Fe3	55.228 (18)	N1—C9—N2	103.9 (2)
S1—Fe2—Fe3	55.008 (18)	N1—C9—Fe1	129.74 (17)
C3—Fe2—Fe1	74.51 (10)	N2—C9—Fe1	126.01 (17)
C4—Fe2—Fe1	135.67 (10)	C10—C15—N2	105.7 (2)
C5—Fe2—Fe1	129.47 (9)	C10—C15—C14	122.9 (2)
S2—Fe2—Fe1	53.760 (18)	N2—C15—C14	131.4 (2)
S1—Fe2—Fe1	53.551 (18)	O2—C2—Fe1	178.4 (3)
Fe3—Fe2—Fe1	81.794 (15)	O8—C8—Fe3	177.5 (3)
C1—Fe1—C2	93.34 (12)	O1—C1—Fe1	178.0 (3)
C1—Fe1—C9	96.89 (11)	C15—C10—C11	120.2 (2)
C2—Fe1—C9	94.73 (11)	C15—C10—N1	105.6 (2)
C1—Fe1—S1	92.65 (8)	C11—C10—N1	134.2 (2)
C2—Fe1—S1	167.53 (8)	O5—C5—Fe2	178.2 (3)
C9—Fe1—S1	95.40 (7)	O4—C4—Fe2	178.4 (3)
C1—Fe1—S2	165.00 (9)	C13—O9—C16	117.3 (2)
C2—Fe1—S2	91.31 (8)	C13—C14—C15	116.2 (2)
C9—Fe1—S2	96.92 (7)	C13—C14—H14A	121.9
S1—Fe1—S2	80.26 (2)	C15—C14—H14A	121.9
C1—Fe1—Fe2	110.82 (9)	O9—C13—C14	123.8 (2)
C2—Fe1—Fe2	112.86 (8)	O9—C13—C12	115.1 (2)
C9—Fe1—Fe2	138.68 (7)	C14—C13—C12	121.1 (2)
S1—Fe1—Fe2	54.701 (19)	O3—C3—Fe2	172.2 (3)
S2—Fe1—Fe2	54.352 (18)	C11—C12—C13	121.7 (2)
C8—Fe3—C6	99.45 (14)	C11—C12—H12A	119.1
C8—Fe3—C7	91.77 (12)	C13—C12—H12A	119.1
C6—Fe3—C7	99.30 (15)	O9—C16—H16A	109.5
C8—Fe3—S1	156.98 (9)	O9—C16—H16B	109.5
C6—Fe3—S1	102.43 (11)	H16A—C16—H16B	109.5
C7—Fe3—S1	91.72 (9)	O9—C16—H16C	109.5
C8—Fe3—S2	90.45 (8)	H16A—C16—H16C	109.5
C6—Fe3—S2	97.38 (10)	H16B—C16—H16C	109.5
C7—Fe3—S2	162.57 (10)	C12—C11—C10	117.8 (2)
S1—Fe3—S2	79.75 (2)	C12—C11—H11A	121.1
C8—Fe3—Fe2	101.57 (9)	C10—C11—H11A	121.1
C6—Fe3—Fe2	145.32 (10)	O6—C6—Fe3	177.5 (3)
C7—Fe3—Fe2	107.26 (10)	O7—C7—Fe3	178.6 (3)
S1—Fe3—Fe2	55.765 (19)

Experimental details

Crystal data
Chemical formula	[Fe₃(C₈H₈N₂O)S₂(CO)₈]
M_r	603.91
Crystal system, space group	Triclinic, P1
Temperature (K)	273
a, b, c (Å)	9.0068 (4), 11.4504 (5), 12.5976 (6)
α, β, γ (°)	112.332 (3), 108.728 (3), 96.229 (3)
V (Å³)	1098.0 (1)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.20
Crystal size (mm)	0.25 × 0.20 × 0.10

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 1997)
T_min, T_max	0.610, 0.810
No. of measured, independent and observed [I > 2σ(I)] reflections	8226, 4253, 3584
R_int	0.019
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.070, 1.05
No. of reflections	4253
No. of parameters	289
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.28, −0.30

Computer programs: SMART (Bruker, 1997), SAINT-Plus (Bruker, 2001), SAINT-Plus, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 1997), SHELXTL.

Selected geometric parameters (Å, º) top

Fe2—S2	2.2505 (7)	Fe1—S1	2.2294 (6)
Fe2—S1	2.2621 (7)	Fe1—S2	2.2337 (7)
Fe2—Fe3	2.5582 (5)	Fe3—S1	2.2415 (6)
Fe2—Fe1	2.6322 (5)	Fe3—S2	2.2455 (6)
Fe1—C9	1.914 (2)

C9—Fe1—Fe2	138.68 (7)	Fe3—S2—Fe2	69.362 (19)
C6—Fe3—Fe2	145.32 (10)	Fe1—S1—Fe3	98.96 (2)
Fe1—S2—Fe3	98.71 (2)	Fe1—S1—Fe2	71.75 (2)
Fe1—S2—Fe2	71.89 (2)	Fe3—S1—Fe2	69.23 (2)

Acknowledgements

We are grateful to the Chinese National Natural Science Foundation (grant Nos. 20471013 and 20633020), the Swedish Energy Agency, the Swedish Research Council and the K & A Wallenberg Foundation for financial support of this work.

References

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