supplementary materials


zl2517 scheme

Acta Cryst. (2012). E68, m1559-m1560    [ doi:10.1107/S1600536812048039 ]

Hexacarbonyl-2[kappa]3C,3[kappa]3C-di-[mu]3-sulfido-tetrakis(tetrahydrofuran-1[kappa]O)calciumdiiron(II)(Fe-Fe)

M. A. Ogienko, D. Y. Naumov and S. N. Konchenko

Abstract top

Reaction between [Fe2([mu]-S2)(CO)6] and [Ca(thf)4(dpp-BIAN)] [dpp-BIAN = 1,2-bis-(2,6-diisopropylphenylimino)acenaphthene and thf = tetrahydrofuran] proceeds as a redox process via a two-electron reduction of [Fe2([mu]-S2)(CO)6] and a two-electron oxidation of (dpp-BIAN)2-, resulting in the formation of the title heterometallic trinuclear cluster, [CaFe2([mu]3-S)2(C4H8O)4(CO)6], and neutral dpp-BIAN. In the cluster, the CaII atom is connected to two S atoms of an Fe2S2 core [Ca-S = 2.7463 (8) and 2.7523 (8) Å]. No Fe-Ca bonds are formed [Fe...Ca = 3.6708 (6) and 3.5802 (6) Å]. There are five close C-H...O-C contacts in the crystal structure.

Comment top

FeS-clusters are part of the active sites of several enzymes such as hydrogenases. The development of model compounds for these kinds of compounds has attracted the attention of chemists for several decades (Gloaguen & Rauchfuss, 2009). In this context we aimed to study the chemical reduction of [Fe2(CO)6(µ-S2)] with a calcium complex containing the redox active ligand 1,2-bis-(2,6-diisopropylphenylimino)acenaphthene (dpp-BIAN) as the reducing agent. Reduction of [Fe2(CO)6(µ-S2)] with [Ca(thf)4(dpp-BIAN)] resulted in the formation of trinuclear calcium iron cluster of the composition [Fe2(CO)63-S)2Ca(thf)4] and neutral dpp-BIAN. Formally the process may be considered as a 2-electron reduction of [Fe2(CO)6(µ-S2)] by (dpp-BIAN)2- located in the coordination sphere of Ca2+. After 2-electron oxidation (dpp-BIAN)2- becomes neutral dpp-BIAN and is readily substituted by O-donor THF molecules due to the extremely high oxophilicity of Ca2+.

The two-electron reduction of [Fe2(CO)6(µ-S2)] by [Ca(thf)4(dpp-BIAN)] led to the formation of the heterometallic trinuclear cluster [Fe2(CO)63-S)2Ca(thf)4]. In the molecule of the cluster the Ca atom is connected to two S atoms of the Fe2S2 core (d(Ca1–S2) = 2.7463 (8) Å; d(Ca1–S1) = 2.7523 (8) Å). In the case observed here, no Fe–Ca bonds are formed (d(Fe2–Ca1) = 3.6708 (6) Å; d(Fe1–Ca1) = 3.5802 (6) Å). All atoms lie in general positions.

The C–O ligands are surrounded by H-atoms from neighboring THF-ligands. There are five close C–H···O–C contacts with O···H distances from 2.571 Å to 2.672 Å (Table 2).

The S–S distances and the S–Fe–Fe–S torsion angle in the Fe2S2 core depend on the atomic radius and the nature of the heterometal. In case of [Fe2(CO)6(µ-S2)] itself with no heterometal attached the S–S distances average 2.021 (2) Å, the S–Fe–Fe–S torsion angle is 66.89 (2) ° (Eremenko et al., 1994). In the case of [Fe2(CO)63-S)2Pt(PPh3)2] d(S–S) is 2.86 (4) Å, the S–Fe–Fe–S torsion angle is 97 (2) ° (Pasynskii et al., 1993). For [Fe2(CO)63-S)2Sn(µ-Nt-Bu)2SiMe2] d(S–S) equals 3.048 (3) Å, the torsion angle is 102.50 (3) ° (Veith et al., 2005), and in [Fe2S2(CO)6Ca(thf)4] described here d(S–S) = 3.129 (3) Å, and the S1–Fe1–Fe2–S2 torsion angle is 107.78 (2) °. The large variability, especially of the S–Fe–Fe–S torsion angle, indicates a pronounced geometric flexibility of the [Fe2(CO)6(µ-S2)] core.

Related literature top

For the synthesis and structure of [Fe2(CO)6(µ-S2)], see: Hieber & Beck (1958); Seyferth et al. (1982), and of [Ca(thf)4(dpp-BIAN)], see: Fedushkin et al. (2003). For the synthesis and structures of related heterometallic clusters with an Fe2S2 core, see: Konchenko et al. (2010); Cowie et al. (1989); Veith et al. (2005); Eremenko et al. (1994); Pasynskii et al. (1993). For FeS-clusters as model compounds for active sites of hydrogenases, see: Gloaguen & Rauchfuss (2009).

Experimental top

All manipulations were carried out under strictly anaerobic and anhydrous conditions. For the synthesis an ampoule possessing two sections (1 and 2) orientated at right angles to each other was used. In an argon glove box [Fe2(CO)6(µ-S)2] (100 mg, 0.29 mmol), [Ca(thf)4(dpp-BIAN)] (241 mg, 0.29 mmol) and a Teflon-coated magnetic stirring bar were placed into section 1. The ampoule was connected to a vacuum condensation line and THF (30 ml) was condensed into the same section cooled by liquid nitrogen. Then, the ampoule was flame sealed and placed on a magnetic stirrer. The reaction mixture was allowed to warm up to room temperature at permanent stirring, which was subsequently continued for 24 h. A black microcrystalline precipitate of crude [Fe2(CO)63-S)2Ca(thf)4] was separated by decantation of the solution to section 2 and washed out by THF in the following manner: the ampoule was mounted so that the section 2 was oriented vertically, section 1 containing the black precipitate was located on top horizontally, a recirculation of THF (evaporation into section 2, condensation into section 1 and flowing down to section 2) was achieved by means of a temperature difference between the sections: 1 - 288 K, 2 - 298 K. In a period of a few days this led to enlargement of the crystallites of [Fe2(CO)63-S)2Ca(thf)4] and complete removal of dpp-BIAN the solid. After that all volatiles were removed from the section 1 by cooling of section 2 with liquid nitrogen. Section 1 with black crystalline [Fe2(CO)63-S)2Ca(thf)4] (yield 60%) was flame sealed and opened in a glovebox. The compound is extremely air sensitive, so satisfactory analytical data were not obtained. Uniformity of the sample was proved by IR spectroscopy which exhibits the expected characteristic pattern in the CO region (cm-1): 2083 m, 2042 s, 2024 s, 2006 s, 1976 s, 1943 s, 1904 s (in mineral oil). Single crystals suitable for X-ray analysis were found in the black crystalline mass. Selection of the crystal for X-ray analysis was performed under a microscope in a glovebox. The crystal was taken up in a drop of mineral oil and was immediately mounted on the diffractometer.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); 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: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of [Fe2(CO)63-S)2Ca(thf)4]. Displacement ellipsoids are plotted at the 50% probability level.
[Figure 2] Fig. 2. Packing of the structure viewed along a axis. H atoms are omitted for clarity.
Hexacarbonyl-2κ3C,3κ3C-di-µ3-sulfido- tetrakis(tetrahydrofuran-1κO)calciumdiiron(II)(FeFe) top
Crystal data top
[CaFe2S2(C4H8O)4(CO)6]F(000) = 1392
Mr = 672.38Dx = 1.535 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 7648 reflections
a = 10.9189 (4) Åθ = 2.5–26.2°
b = 12.4167 (5) ŵ = 1.37 mm1
c = 21.4545 (9) ÅT = 150 K
V = 2908.7 (2) Å3Prism, black
Z = 40.25 × 0.11 × 0.08 mm
Data collection top
Bruker–Nonius X8 APEX CCD area-detector
diffractometer
5951 independent reflections
Radiation source: fine-focus sealed tube5319 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.033
Detector resolution: 25 pixels mm-1θmax = 26.4°, θmin = 1.9°
φ scansh = 1311
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
k = 1315
Tmin = 0.726, Tmax = 0.899l = 2626
21313 measured reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.057 w = 1/[σ2(Fo2) + (0.029P)2]
where P = (Fo2 + 2Fc2)/3
S = 1.01(Δ/σ)max = 0.002
5951 reflectionsΔρmax = 0.36 e Å3
334 parametersΔρmin = 0.32 e Å3
0 restraintsAbsolute structure: Flack (1983), 2601 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.006 (11)
Crystal data top
[CaFe2S2(C4H8O)4(CO)6]V = 2908.7 (2) Å3
Mr = 672.38Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 10.9189 (4) ŵ = 1.37 mm1
b = 12.4167 (5) ÅT = 150 K
c = 21.4545 (9) Å0.25 × 0.11 × 0.08 mm
Data collection top
Bruker–Nonius X8 APEX CCD area-detector
diffractometer
5951 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2004)
5319 reflections with I > 2σ(I)
Tmin = 0.726, Tmax = 0.899Rint = 0.033
21313 measured reflectionsθmax = 26.4°
Refinement top
R[F2 > 2σ(F2)] = 0.027H-atom parameters constrained
wR(F2) = 0.057Δρmax = 0.36 e Å3
S = 1.01Δρmin = 0.32 e Å3
5951 reflectionsAbsolute structure: Flack (1983), 2601 Friedel pairs
334 parametersFlack parameter: 0.006 (11)
0 restraints
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
xyzUiso*/Ueq
Fe10.79820 (3)0.40586 (3)0.674330 (16)0.02253 (8)
Fe20.82499 (3)0.59531 (3)0.635135 (17)0.02489 (9)
Ca10.51290 (4)0.49436 (4)0.60998 (2)0.01931 (10)
S10.67335 (5)0.54573 (5)0.70434 (3)0.02536 (14)
S20.75029 (6)0.45765 (5)0.57341 (3)0.02487 (14)
O11.02452 (18)0.32234 (16)0.61922 (10)0.0441 (5)
O20.88333 (18)0.40811 (19)0.80361 (9)0.0479 (5)
O30.64995 (17)0.21109 (14)0.69010 (9)0.0348 (5)
O41.04619 (17)0.58348 (18)0.55847 (9)0.0467 (5)
O50.9470 (2)0.68878 (18)0.74443 (11)0.0561 (6)
O60.71495 (19)0.78658 (16)0.57777 (10)0.0459 (5)
O110.35797 (14)0.48969 (14)0.68605 (8)0.0259 (4)
O210.44972 (16)0.30895 (12)0.59998 (8)0.0287 (4)
O310.43354 (16)0.49442 (14)0.50679 (8)0.0284 (4)
O410.44134 (17)0.67554 (12)0.60327 (8)0.0278 (4)
C10.9361 (3)0.3532 (2)0.64150 (13)0.0301 (6)
C20.8518 (2)0.4082 (2)0.75288 (12)0.0302 (6)
C30.7062 (2)0.2881 (2)0.68292 (11)0.0254 (5)
C40.9604 (2)0.5880 (2)0.58892 (13)0.0325 (6)
C50.8992 (3)0.6536 (2)0.70162 (15)0.0353 (7)
C60.7565 (2)0.7112 (2)0.60022 (13)0.0317 (6)
C120.3812 (3)0.4509 (2)0.74846 (13)0.0350 (7)
H12A0.41710.50840.77470.042*
H12B0.43780.38870.74780.042*
C130.2579 (3)0.4183 (3)0.77249 (15)0.0525 (9)
H13A0.25470.42210.81860.063*
H13B0.23650.34440.75900.063*
C140.1737 (3)0.5006 (3)0.74314 (15)0.0529 (9)
H14A0.08930.47240.73940.063*
H14B0.17220.56810.76770.063*
C150.2301 (2)0.5187 (2)0.67990 (14)0.0345 (6)
H15A0.18950.47310.64820.041*
H15B0.22180.59510.66730.041*
C220.3577 (3)0.2470 (2)0.63353 (15)0.0365 (7)
H22A0.28000.28780.63670.044*
H22B0.38650.22930.67610.044*
C230.3400 (3)0.1453 (2)0.59526 (15)0.0431 (8)
H23A0.31380.08420.62180.052*
H23B0.27900.15630.56170.052*
C240.4666 (3)0.1266 (2)0.56874 (14)0.0385 (7)
H24A0.46350.08110.53090.046*
H24B0.52140.09260.59980.046*
C250.5076 (3)0.2404 (2)0.55347 (13)0.0347 (7)
H25A0.59790.24630.55590.042*
H25B0.48110.26090.51100.042*
C320.3135 (2)0.4568 (2)0.48866 (12)0.0314 (6)
H32A0.25480.51750.48690.038*
H32B0.28280.40270.51870.038*
C330.3296 (3)0.4070 (3)0.42478 (13)0.0442 (7)
H33A0.32640.32750.42720.053*
H33B0.26510.43230.39580.053*
C340.4545 (4)0.4447 (4)0.40367 (16)0.0787 (14)
H34A0.50970.38220.39780.094*
H34B0.44780.48370.36360.094*
C350.5017 (3)0.5140 (3)0.45056 (13)0.0566 (10)
H35A0.49280.59020.43770.068*
H35B0.58980.49910.45750.068*
C420.3891 (3)0.7332 (2)0.55093 (13)0.0458 (9)
H42A0.32440.68960.53070.055*
H42B0.45300.75000.51970.055*
C430.3355 (3)0.8361 (2)0.57789 (14)0.0410 (7)
H43A0.33710.89540.54710.049*
H43B0.25040.82500.59240.049*
C440.4212 (3)0.8579 (2)0.63176 (13)0.0336 (6)
H44A0.38180.90410.66360.040*
H44B0.49770.89270.61740.040*
C450.4458 (3)0.7462 (2)0.65700 (12)0.0323 (7)
H45A0.52720.74300.67720.039*
H45B0.38260.72560.68790.039*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Fe10.02134 (17)0.02364 (17)0.02262 (17)0.00130 (15)0.00090 (15)0.00073 (16)
Fe20.02297 (18)0.02352 (18)0.02818 (19)0.00199 (15)0.00003 (16)0.00004 (16)
Ca10.0206 (2)0.0174 (2)0.0200 (2)0.00045 (19)0.0008 (2)0.0010 (2)
S10.0212 (3)0.0320 (3)0.0229 (3)0.0001 (3)0.0003 (3)0.0069 (3)
S20.0221 (3)0.0320 (3)0.0205 (3)0.0010 (3)0.0008 (3)0.0038 (3)
O10.0291 (11)0.0478 (12)0.0555 (14)0.0062 (9)0.0066 (10)0.0083 (11)
O20.0443 (12)0.0709 (14)0.0286 (11)0.0113 (11)0.0107 (9)0.0019 (11)
O30.0381 (11)0.0308 (10)0.0355 (11)0.0085 (9)0.0007 (9)0.0050 (9)
O40.0287 (11)0.0664 (15)0.0450 (13)0.0017 (10)0.0092 (10)0.0121 (11)
O50.0552 (15)0.0513 (14)0.0618 (15)0.0080 (12)0.0199 (13)0.0194 (12)
O60.0474 (13)0.0367 (12)0.0536 (13)0.0089 (10)0.0131 (11)0.0177 (11)
O110.0215 (9)0.0311 (9)0.0251 (9)0.0010 (7)0.0008 (7)0.0064 (8)
O210.0337 (10)0.0173 (8)0.0351 (11)0.0034 (8)0.0009 (8)0.0027 (8)
O310.0287 (9)0.0347 (9)0.0216 (9)0.0068 (8)0.0037 (7)0.0046 (8)
O410.0457 (11)0.0165 (8)0.0211 (9)0.0027 (8)0.0039 (8)0.0005 (7)
C10.0288 (15)0.0287 (14)0.0327 (15)0.0034 (11)0.0052 (13)0.0009 (12)
C20.0258 (14)0.0332 (14)0.0317 (15)0.0054 (12)0.0007 (11)0.0002 (13)
C30.0259 (13)0.0301 (14)0.0201 (13)0.0042 (11)0.0003 (11)0.0015 (11)
C40.0297 (15)0.0330 (15)0.0348 (16)0.0065 (13)0.0056 (13)0.0094 (13)
C50.0298 (15)0.0282 (14)0.0481 (18)0.0011 (12)0.0051 (14)0.0031 (14)
C60.0301 (14)0.0309 (15)0.0343 (16)0.0048 (12)0.0097 (13)0.0020 (13)
C120.0436 (17)0.0327 (15)0.0286 (15)0.0051 (13)0.0018 (12)0.0076 (12)
C130.070 (2)0.0479 (19)0.0393 (18)0.0196 (18)0.0223 (17)0.0036 (15)
C140.0278 (16)0.074 (2)0.057 (2)0.0113 (17)0.0132 (15)0.0199 (18)
C150.0214 (14)0.0376 (16)0.0444 (16)0.0007 (11)0.0016 (12)0.0003 (14)
C220.0353 (16)0.0262 (14)0.0481 (18)0.0054 (11)0.0045 (14)0.0005 (14)
C230.0445 (18)0.0223 (14)0.062 (2)0.0072 (13)0.0101 (16)0.0049 (14)
C240.0493 (19)0.0211 (14)0.0452 (18)0.0025 (12)0.0067 (15)0.0104 (12)
C250.0444 (18)0.0262 (14)0.0336 (16)0.0033 (12)0.0011 (14)0.0063 (12)
C320.0251 (13)0.0353 (14)0.0337 (14)0.0005 (12)0.0032 (12)0.0006 (12)
C330.0467 (18)0.0561 (19)0.0298 (15)0.0167 (17)0.0119 (14)0.0038 (15)
C340.083 (3)0.117 (3)0.037 (2)0.055 (3)0.0211 (19)0.026 (2)
C350.0482 (19)0.093 (3)0.0284 (16)0.0292 (19)0.0058 (14)0.0035 (17)
C420.085 (3)0.0277 (16)0.0253 (16)0.0141 (15)0.0124 (16)0.0010 (12)
C430.056 (2)0.0279 (15)0.0388 (17)0.0138 (14)0.0080 (15)0.0006 (13)
C440.0411 (16)0.0207 (13)0.0388 (16)0.0087 (11)0.0040 (14)0.0054 (12)
C450.0480 (18)0.0257 (14)0.0232 (15)0.0006 (12)0.0011 (12)0.0066 (11)
Geometric parameters (Å, º) top
Fe1—C31.784 (3)C14—C151.507 (4)
Fe1—C21.784 (3)C14—H14A0.9900
Fe1—C11.786 (3)C14—H14B0.9900
Fe1—Fe22.5152 (5)C15—H15A0.9900
Fe1—S12.2999 (7)C15—H15B0.9900
Fe1—S22.3185 (7)C22—C231.519 (4)
Fe2—S12.3077 (7)C22—H22A0.9900
Fe2—S22.3110 (7)C22—H22B0.9900
Ca1—S12.7523 (8)C23—C241.513 (4)
Ca1—S22.7463 (8)C23—H23A0.9900
Ca1—Fe13.5802 (6)C23—H23B0.9900
Ca1—Fe23.6708 (6)C24—C251.517 (4)
Fe2—C41.783 (3)C24—H24A0.9900
Fe2—C61.787 (3)C24—H24B0.9900
Fe2—C51.793 (3)C25—H25A0.9900
Ca1—O112.3513 (17)C25—H25B0.9900
Ca1—O312.3773 (17)C32—C331.514 (4)
Ca1—O412.3858 (16)C32—H32A0.9900
Ca1—O212.4128 (16)C32—H32B0.9900
O1—C11.144 (3)C33—C341.511 (4)
O2—C21.142 (3)C33—H33A0.9900
O3—C31.147 (3)C33—H33B0.9900
O4—C41.143 (3)C34—C351.421 (4)
O5—C51.143 (3)C34—H34A0.9900
O6—C61.146 (3)C34—H34B0.9900
O11—C121.445 (3)C35—H35A0.9900
O11—C151.448 (3)C35—H35B0.9900
O21—C221.456 (3)C42—C431.519 (4)
O21—C251.456 (3)C42—H42A0.9900
O31—C351.438 (3)C42—H42B0.9900
O31—C321.445 (3)C43—C441.511 (4)
O41—C421.449 (3)C43—H43A0.9900
O41—C451.450 (3)C43—H43B0.9900
C12—C131.498 (4)C44—C451.513 (3)
C12—H12A0.9900C44—H44A0.9900
C12—H12B0.9900C44—H44B0.9900
C13—C141.512 (5)C45—H45A0.9900
C13—H13A0.9900C45—H45B0.9900
C13—H13B0.9900
C3—Fe1—C295.79 (12)O11—C12—H12A110.8
C3—Fe1—C1102.44 (11)C13—C12—H12A110.8
C2—Fe1—C195.85 (12)O11—C12—H12B110.8
C3—Fe1—S1104.86 (8)C13—C12—H12B110.8
C2—Fe1—S185.27 (9)H12A—C12—H12B108.9
C1—Fe1—S1152.42 (9)C12—C13—C14102.7 (2)
C3—Fe1—S2101.35 (8)C12—C13—H13A111.2
C2—Fe1—S2162.08 (9)C14—C13—H13A111.2
C1—Fe1—S285.60 (9)C12—C13—H13B111.2
S1—Fe1—S285.31 (2)C14—C13—H13B111.2
C3—Fe1—Fe2150.09 (8)H13A—C13—H13B109.1
C2—Fe1—Fe2105.19 (9)C15—C14—C13103.2 (2)
C1—Fe1—Fe296.45 (9)C15—C14—H14A111.1
S1—Fe1—Fe257.06 (2)C13—C14—H14A111.1
S2—Fe1—Fe256.95 (2)C15—C14—H14B111.1
C3—Fe1—Ca178.55 (8)C13—C14—H14B111.1
C2—Fe1—Ca1130.14 (9)H14A—C14—H14B109.1
C1—Fe1—Ca1133.92 (9)O11—C15—C14105.9 (2)
S1—Fe1—Ca150.242 (18)O11—C15—H15A110.6
S2—Fe1—Ca150.091 (18)C14—C15—H15A110.6
Fe2—Fe1—Ca171.653 (13)O11—C15—H15B110.6
C4—Fe2—C698.93 (12)C14—C15—H15B110.6
C4—Fe2—C595.07 (13)H15A—C15—H15B108.7
C6—Fe2—C5101.39 (12)O21—C22—C23105.1 (2)
C4—Fe2—S1159.96 (9)O21—C22—H22A110.7
C6—Fe2—S1100.61 (9)C23—C22—H22A110.7
C5—Fe2—S185.40 (10)O21—C22—H22B110.7
C4—Fe2—S286.35 (9)C23—C22—H22B110.7
C6—Fe2—S2101.99 (9)H22A—C22—H22B108.8
C5—Fe2—S2156.06 (9)C24—C23—C22102.4 (2)
S1—Fe2—S285.31 (2)C24—C23—H23A111.3
C4—Fe2—Fe1103.58 (9)C22—C23—H23A111.3
C6—Fe2—Fe1147.66 (9)C24—C23—H23B111.3
C5—Fe2—Fe199.45 (9)C22—C23—H23B111.3
S1—Fe2—Fe156.767 (19)H23A—C23—H23B109.2
S2—Fe2—Fe157.24 (2)C23—C24—C25102.0 (2)
C4—Fe2—Ca1132.13 (9)C23—C24—H24A111.4
C6—Fe2—Ca179.91 (9)C25—C24—H24A111.4
C5—Fe2—Ca1132.39 (10)C23—C24—H24B111.4
S1—Fe2—Ca148.504 (18)C25—C24—H24B111.4
S2—Fe2—Ca148.359 (18)H24A—C24—H24B109.2
Fe1—Fe2—Ca167.779 (13)O21—C25—C24105.6 (2)
O11—Ca1—O31112.59 (6)O21—C25—H25A110.6
O11—Ca1—O4180.18 (6)C24—C25—H25A110.6
O31—Ca1—O4179.87 (6)O21—C25—H25B110.6
O11—Ca1—O2180.36 (6)C24—C25—H25B110.6
O31—Ca1—O2179.24 (6)H25A—C25—H25B108.8
O41—Ca1—O21143.19 (6)O31—C32—C33105.7 (2)
O11—Ca1—S2150.84 (5)O31—C32—H32A110.6
O31—Ca1—S294.48 (5)C33—C32—H32A110.6
O41—Ca1—S2116.64 (5)O31—C32—H32B110.6
O21—Ca1—S294.94 (5)C33—C32—H32B110.6
O11—Ca1—S187.31 (5)H32A—C32—H32B108.7
O31—Ca1—S1156.48 (5)C34—C33—C32104.5 (2)
O41—Ca1—S191.96 (5)C34—C33—H33A110.9
O21—Ca1—S1117.94 (5)C32—C33—H33A110.9
S2—Ca1—S169.38 (2)C34—C33—H33B110.9
O11—Ca1—Fe1110.53 (4)C32—C33—H33B110.9
O31—Ca1—Fe1132.56 (5)H33A—C33—H33B108.9
O41—Ca1—Fe1126.70 (5)C35—C34—C33107.6 (3)
O21—Ca1—Fe189.44 (4)C35—C34—H34A110.2
S2—Ca1—Fe140.358 (15)C33—C34—H34A110.2
S1—Ca1—Fe139.970 (15)C35—C34—H34B110.2
O11—Ca1—Fe2125.05 (5)C33—C34—H34B110.2
O31—Ca1—Fe2118.37 (4)H34A—C34—H34B108.5
O41—Ca1—Fe289.48 (5)C34—C35—O31107.7 (3)
O21—Ca1—Fe2127.18 (4)C34—C35—H35A110.2
S2—Ca1—Fe238.966 (16)O31—C35—H35A110.2
S1—Ca1—Fe238.903 (15)C34—C35—H35B110.2
Fe1—Ca1—Fe240.568 (10)O31—C35—H35B110.2
Fe1—S1—Fe266.17 (2)H35A—C35—H35B108.5
Fe1—S1—Ca189.79 (2)O41—C42—C43105.8 (2)
Fe2—S1—Ca192.59 (2)O41—C42—H42A110.6
Fe2—S2—Fe165.82 (2)C43—C42—H42A110.6
Fe2—S2—Ca192.67 (2)O41—C42—H42B110.6
Fe1—S2—Ca189.55 (2)C43—C42—H42B110.6
C12—O11—C15109.66 (19)H42A—C42—H42B108.7
C12—O11—Ca1121.67 (15)C44—C43—C42101.7 (2)
C15—O11—Ca1128.63 (16)C44—C43—H43A111.4
C22—O21—C25109.24 (18)C42—C43—H43A111.4
C22—O21—Ca1131.11 (15)C44—C43—H43B111.4
C25—O21—Ca1119.65 (15)C42—C43—H43B111.4
C35—O31—C32107.36 (19)H43A—C43—H43B109.3
C35—O31—Ca1126.33 (16)C43—C44—C45102.7 (2)
C32—O31—Ca1125.54 (14)C43—C44—H44A111.2
C42—O41—C45109.29 (18)C45—C44—H44A111.2
C42—O41—Ca1129.91 (15)C43—C44—H44B111.2
C45—O41—Ca1120.79 (14)C45—C44—H44B111.2
O1—C1—Fe1177.8 (3)H44A—C44—H44B109.1
O2—C2—Fe1178.1 (2)O41—C45—C44105.3 (2)
O3—C3—Fe1177.5 (2)O41—C45—H45A110.7
O4—C4—Fe2178.9 (2)C44—C45—H45A110.7
O5—C5—Fe2178.7 (3)O41—C45—H45B110.7
O6—C6—Fe2178.5 (2)C44—C45—H45B110.7
O11—C12—C13104.6 (2)H45A—C45—H45B108.8
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C34—H34A···O1i0.992.573.437 (5)146
C34—H34B···O2ii0.992.623.329 (4)129
C42—H42A···O6iii0.992.633.362 (4)131
C45—H45B···O3iv0.992.653.470 (3)141
C15—H15A···O1v0.992.673.561 (3)150
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+3/2, y+1, z1/2; (iii) x1/2, y+3/2, z+1; (iv) x+1, y+1/2, z+3/2; (v) x1, y, z.
Selected bond lengths (Å) top
Fe1—Fe22.5152 (5)Ca1—S12.7523 (8)
Fe1—S12.2999 (7)Ca1—S22.7463 (8)
Fe1—S22.3185 (7)Ca1—Fe13.5802 (6)
Fe2—S12.3077 (7)Ca1—Fe23.6708 (6)
Fe2—S22.3110 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C34—H34A···O1i0.992.573.437 (5)146.2
C34—H34B···O2ii0.992.623.329 (4)128.8
C42—H42A···O6iii0.992.633.362 (4)130.6
C45—H45B···O3iv0.992.653.470 (3)140.7
C15—H15A···O1v0.992.673.561 (3)149.6
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+3/2, y+1, z1/2; (iii) x1/2, y+3/2, z+1; (iv) x+1, y+1/2, z+3/2; (v) x1, y, z.
Acknowledgements top

The authors are grateful to the Russian Foundation for Basic Research (grant Nos. 10-03-00385, 12-03-31759 and 12- 03-31530) and the Federal target program Kadry (contract No. 8631) for financial support.

references
References top

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