
Acta Cryst. (2010). E66, m299-m300 [ doi:10.1107/S1600536810005489 ]
2O,O')molybdenum(III)In the title compound, [Mo(C5HF6O2)3], the unit cell is built up by three independent MoIII atoms located on two different threefold axes. The three independent molecules are roughly identical and each MoIII atom is surrounded by three chelating hexafluoroacetonate ligands in a three-bladed propeller-like arrangement, as observed in related compounds with acetylacetonate-type ligands. The structure of the title compound is very similar to the trigonal form of the CrIII analogue. However, the latter crystallizes in a higher-symmetry space group, P
c1. Both crystals are twinned by merohedry with the same twin law (![]()
0/010/00
) in reciprocal space, but the symmetry of the Laue group in which it operates is different,
to
m for the title complex, and
m to 6/mmm for the CrIII complex.
The compound was prepared by refluxing Mo(CO)6 in toluene in the presence of 3 equivalents of 1,1,1,5,5,5-hexafluoropentan-2,4-dione and a few drops of diglyme which is known to facilitate CO replacement reactions for the carbonyl molybdenum precursor. Single crystals of the product grew directly from the solution after cooling, concentration, filtration at room temperature, and further cooling to -20°C.
The crystal is twinned by merohedry with the -1 -1 0 0 1 0 0 0 -1 twin law in the reciprocal space. A scale factor for the major twin domain is 0.8076 (9).
The three H atoms attached to the central C atoms were fixed geometrically and treated as riding with C—H = 0.95 Å with Uiso(H) = 1.2Ueq(C).
Data collection: CrysAlis CCD (Oxford Diffraction, 2008); cell refinement: CrysAlis RED (Oxford Diffraction, 2008); data reduction: CrysAlis RED (Oxford Diffraction, 2008); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
| [Mo(C5HF6O2)3] | Dx = 2.099 Mg m−3 |
| Mr = 717.11 | Mo Kα radiation, λ = 0.71073 Å |
| Trigonal, P3 | Cell parameters from 8040 reflections |
| a = 18.4876 (10) Å | θ = 2.8–32.1° |
| c = 11.5021 (7) Å | µ = 0.76 mm−1 |
| V = 3404.6 (3) Å3 | T = 180 K |
| Z = 6 | Prism, dark green |
| F(000) = 2070 | 0.39 × 0.11 × 0.05 mm |
| Oxford Diffraction XCALIBUR diffractometer | 4635 independent reflections |
| Radiation source: fine-focus sealed tube | 2801 reflections with I > 2σ(I) |
| graphite | Rint = 0.063 |
| Detector resolution: 8.2632 pixels mm-1 | θmax = 26.4°, θmin = 2.8° |
| ω and φ scans | h = −23→23 |
| Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | k = −23→23 |
| Tmin = 0.731, Tmax = 1.000 | l = −14→14 |
| 26629 measured reflections |
| 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)] = 0.030 | Hydrogen site location: inferred from neighbouring sites |
| wR(F2) = 0.068 | H-atom parameters constrained |
| S = 0.97 | w = 1/[σ2(Fo2) + (0.0279P)2] where P = (Fo2 + 2Fc2)/3 |
| 4635 reflections | (Δ/σ)max = 0.001 |
| 362 parameters | Δρmax = 0.78 e Å−3 |
| 0 restraints | Δρmin = −0.44 e Å−3 |
| [Mo(C5HF6O2)3] | Z = 6 |
| Mr = 717.11 | Mo Kα radiation |
| Trigonal, P3 | µ = 0.76 mm−1 |
| a = 18.4876 (10) Å | T = 180 K |
| c = 11.5021 (7) Å | 0.39 × 0.11 × 0.05 mm |
| V = 3404.6 (3) Å3 |
| Oxford Diffraction XCALIBUR diffractometer | 4635 independent reflections |
| Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008) | 2801 reflections with I > 2σ(I) |
| Tmin = 0.731, Tmax = 1.000 | Rint = 0.063 |
| 26629 measured reflections | θmax = 26.4° |
| R[F2 > 2σ(F2)] = 0.030 | H-atom parameters constrained |
| wR(F2) = 0.068 | Δρmax = 0.78 e Å−3 |
| S = 0.97 | Δρmin = −0.44 e Å−3 |
| 4635 reflections | Absolute structure: ? |
| 362 parameters | Flack parameter: ? |
| 0 restraints | Rogers parameter: ? |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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. |
| x | y | z | Uiso*/Ueq | ||
| Mo1 | 1.0000 | 1.0000 | 0.22101 (5) | 0.02614 (14) | |
| O11 | 0.92251 (14) | 1.02746 (14) | 0.12480 (19) | 0.0300 (6) | |
| O12 | 0.89820 (15) | 0.92784 (14) | 0.3234 (2) | 0.0328 (6) | |
| C11 | 0.8485 (2) | 1.0084 (2) | 0.1500 (3) | 0.0292 (9) | |
| C12 | 0.8278 (2) | 0.9228 (2) | 0.3202 (3) | 0.0334 (9) | |
| C13 | 0.8008 (2) | 0.9608 (2) | 0.2420 (3) | 0.0346 (10) | |
| H13 | 0.7466 | 0.9537 | 0.2521 | 0.042* | |
| C111 | 0.8113 (3) | 1.0438 (3) | 0.0641 (4) | 0.0412 (10) | |
| C121 | 0.7685 (3) | 0.8663 (3) | 0.4136 (3) | 0.0429 (11) | |
| F11 | 0.84649 (19) | 1.12517 (17) | 0.0790 (2) | 0.0781 (9) | |
| F12 | 0.82575 (17) | 1.03301 (18) | −0.0431 (2) | 0.0653 (8) | |
| F13 | 0.73139 (16) | 1.01295 (19) | 0.0767 (2) | 0.0829 (10) | |
| F14 | 0.74487 (16) | 0.78765 (16) | 0.3919 (2) | 0.0704 (8) | |
| F15 | 0.70096 (14) | 0.87247 (17) | 0.4230 (2) | 0.0698 (9) | |
| F16 | 0.80526 (14) | 0.88434 (15) | 0.51746 (18) | 0.0532 (7) | |
| Mo2 | 0.3333 | 0.6667 | 1.02042 (5) | 0.03124 (15) | |
| O21 | 0.39312 (16) | 0.77397 (15) | 0.92317 (19) | 0.0357 (6) | |
| O22 | 0.28812 (16) | 0.72680 (17) | 1.1206 (2) | 0.0370 (6) | |
| C21 | 0.3944 (2) | 0.8419 (2) | 0.9427 (3) | 0.0351 (10) | |
| C22 | 0.3029 (2) | 0.8010 (3) | 1.1092 (3) | 0.0332 (10) | |
| C23 | 0.3536 (3) | 0.8590 (2) | 1.0281 (3) | 0.0373 (10) | |
| H23 | 0.3606 | 0.9135 | 1.0316 | 0.045* | |
| C211 | 0.4503 (4) | 0.9104 (3) | 0.8578 (4) | 0.0564 (12) | |
| C221 | 0.2561 (3) | 0.8234 (3) | 1.1961 (4) | 0.0548 (13) | |
| F21 | 0.5295 (2) | 0.93326 (19) | 0.8780 (3) | 0.0991 (11) | |
| F22 | 0.4346 (2) | 0.88536 (15) | 0.7498 (2) | 0.0870 (10) | |
| F23 | 0.4454 (2) | 0.97810 (17) | 0.8698 (2) | 0.0875 (10) | |
| F24 | 0.1770 (2) | 0.7858 (2) | 1.1699 (3) | 0.1105 (13) | |
| F25 | 0.26262 (18) | 0.80214 (18) | 1.3017 (2) | 0.0743 (9) | |
| F26 | 0.2806 (2) | 0.9036 (2) | 1.1958 (3) | 0.1124 (13) | |
| Mo3 | 0.3333 | 0.6667 | 0.54730 (5) | 0.03462 (16) | |
| O31 | 0.39271 (18) | 0.77270 (15) | 0.4469 (2) | 0.0403 (6) | |
| O32 | 0.44118 (15) | 0.71545 (18) | 0.64445 (19) | 0.0377 (6) | |
| C31 | 0.4665 (3) | 0.8327 (3) | 0.4578 (3) | 0.0385 (10) | |
| C32 | 0.5086 (2) | 0.7827 (3) | 0.6246 (3) | 0.0367 (10) | |
| C33 | 0.5252 (2) | 0.8409 (2) | 0.5390 (3) | 0.0377 (10) | |
| H33 | 0.5793 | 0.8888 | 0.5356 | 0.045* | |
| C311 | 0.4891 (4) | 0.8998 (3) | 0.3686 (4) | 0.0582 (14) | |
| C321 | 0.5779 (3) | 0.7956 (4) | 0.7077 (4) | 0.0577 (13) | |
| F31 | 0.4518 (2) | 0.94281 (18) | 0.3915 (3) | 0.0957 (11) | |
| F32 | 0.56998 (19) | 0.95469 (18) | 0.3661 (2) | 0.0947 (11) | |
| F33 | 0.46553 (18) | 0.86962 (17) | 0.2642 (2) | 0.0817 (10) | |
| F34 | 0.6111 (2) | 0.7510 (3) | 0.6743 (3) | 0.1150 (13) | |
| F35 | 0.55263 (14) | 0.7768 (2) | 0.8139 (2) | 0.0820 (9) | |
| F36 | 0.64080 (17) | 0.8732 (2) | 0.7069 (3) | 0.0984 (12) |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Mo1 | 0.02183 (17) | 0.02183 (17) | 0.0348 (3) | 0.01092 (9) | 0.000 | 0.000 |
| O11 | 0.0287 (15) | 0.0307 (15) | 0.0327 (15) | 0.0163 (13) | 0.0021 (12) | 0.0054 (11) |
| O12 | 0.0271 (15) | 0.0280 (15) | 0.0375 (16) | 0.0094 (12) | −0.0027 (12) | 0.0045 (11) |
| C11 | 0.030 (2) | 0.031 (2) | 0.029 (2) | 0.017 (2) | −0.0049 (19) | −0.0059 (18) |
| C12 | 0.028 (2) | 0.030 (2) | 0.032 (2) | 0.007 (2) | −0.0054 (17) | −0.0056 (19) |
| C13 | 0.028 (2) | 0.046 (3) | 0.030 (2) | 0.019 (2) | −0.0003 (19) | −0.001 (2) |
| C111 | 0.041 (3) | 0.055 (3) | 0.038 (3) | 0.031 (3) | 0.006 (2) | 0.007 (2) |
| C121 | 0.035 (3) | 0.051 (3) | 0.032 (3) | 0.013 (2) | −0.001 (2) | 0.005 (2) |
| F11 | 0.112 (3) | 0.058 (2) | 0.089 (2) | 0.061 (2) | −0.0238 (18) | −0.0026 (16) |
| F12 | 0.095 (2) | 0.102 (2) | 0.0347 (15) | 0.0761 (19) | −0.0062 (14) | 0.0026 (14) |
| F13 | 0.0444 (17) | 0.129 (3) | 0.089 (2) | 0.0540 (18) | 0.0083 (15) | 0.0499 (19) |
| F14 | 0.072 (2) | 0.0407 (17) | 0.0615 (18) | 0.0002 (15) | 0.0110 (14) | 0.0096 (14) |
| F15 | 0.0354 (14) | 0.116 (3) | 0.0551 (16) | 0.0353 (15) | 0.0171 (12) | 0.0278 (15) |
| F16 | 0.0472 (14) | 0.0699 (18) | 0.0291 (13) | 0.0192 (14) | −0.0013 (11) | 0.0068 (12) |
| Mo2 | 0.0247 (2) | 0.0247 (2) | 0.0442 (4) | 0.01237 (10) | 0.000 | 0.000 |
| O21 | 0.0316 (16) | 0.0292 (15) | 0.0412 (16) | 0.0112 (13) | 0.0095 (14) | 0.0001 (11) |
| O22 | 0.0373 (17) | 0.0328 (17) | 0.0435 (16) | 0.0195 (14) | 0.0119 (14) | 0.0073 (14) |
| C21 | 0.041 (3) | 0.028 (2) | 0.029 (2) | 0.011 (2) | 0.0001 (19) | −0.0001 (19) |
| C22 | 0.039 (2) | 0.040 (3) | 0.030 (2) | 0.027 (2) | −0.0014 (19) | 0.000 (2) |
| C23 | 0.053 (3) | 0.032 (2) | 0.033 (2) | 0.026 (2) | 0.003 (2) | −0.002 (2) |
| C211 | 0.068 (4) | 0.038 (3) | 0.044 (3) | 0.013 (3) | 0.020 (3) | 0.010 (2) |
| C221 | 0.068 (4) | 0.066 (3) | 0.051 (3) | 0.048 (3) | 0.011 (3) | 0.007 (3) |
| F21 | 0.066 (2) | 0.067 (2) | 0.120 (3) | −0.0003 (18) | 0.031 (2) | 0.0258 (19) |
| F22 | 0.141 (3) | 0.0547 (16) | 0.0318 (15) | 0.024 (2) | 0.0277 (18) | 0.0060 (12) |
| F23 | 0.152 (3) | 0.0401 (17) | 0.0640 (19) | 0.0431 (19) | 0.0365 (18) | 0.0197 (14) |
| F24 | 0.074 (2) | 0.199 (4) | 0.098 (2) | 0.098 (3) | 0.006 (2) | −0.024 (2) |
| F25 | 0.113 (2) | 0.113 (2) | 0.0348 (16) | 0.086 (2) | 0.0201 (15) | 0.0130 (15) |
| F26 | 0.203 (4) | 0.091 (2) | 0.095 (2) | 0.112 (3) | 0.065 (2) | 0.0199 (19) |
| Mo3 | 0.0314 (2) | 0.0314 (2) | 0.0411 (4) | 0.01569 (11) | 0.000 | 0.000 |
| O31 | 0.0419 (18) | 0.0353 (15) | 0.0406 (16) | 0.0170 (16) | −0.0086 (15) | 0.0052 (12) |
| O32 | 0.0329 (15) | 0.0398 (17) | 0.0394 (16) | 0.0175 (15) | 0.0020 (12) | 0.0113 (14) |
| C31 | 0.050 (3) | 0.035 (3) | 0.031 (3) | 0.021 (2) | −0.001 (2) | 0.001 (2) |
| C32 | 0.030 (2) | 0.049 (3) | 0.032 (2) | 0.020 (2) | 0.0040 (19) | 0.007 (2) |
| C33 | 0.032 (2) | 0.042 (3) | 0.031 (2) | 0.012 (2) | 0.0044 (19) | 0.005 (2) |
| C311 | 0.071 (4) | 0.040 (3) | 0.045 (3) | 0.014 (3) | −0.012 (3) | 0.007 (3) |
| C321 | 0.037 (3) | 0.082 (4) | 0.048 (3) | 0.026 (3) | −0.001 (2) | 0.016 (3) |
| F31 | 0.148 (3) | 0.067 (2) | 0.096 (2) | 0.072 (2) | −0.003 (2) | 0.0206 (17) |
| F32 | 0.079 (2) | 0.068 (2) | 0.087 (2) | 0.0004 (19) | −0.0146 (18) | 0.0430 (17) |
| F33 | 0.114 (3) | 0.0654 (19) | 0.0379 (16) | 0.0244 (18) | −0.0140 (16) | 0.0115 (14) |
| F34 | 0.097 (3) | 0.183 (4) | 0.117 (3) | 0.108 (3) | −0.030 (2) | −0.012 (3) |
| F35 | 0.0481 (15) | 0.124 (3) | 0.0445 (16) | 0.0212 (19) | −0.0042 (12) | 0.0350 (19) |
| F36 | 0.0482 (18) | 0.103 (3) | 0.083 (2) | −0.0081 (19) | −0.0228 (16) | 0.0361 (19) |
| Mo1—O12 | 2.049 (2) | C23—H23 | 0.9500 |
| Mo1—O11 | 2.064 (2) | C211—F23 | 1.306 (5) |
| O11—C11 | 1.265 (4) | C211—F22 | 1.306 (5) |
| O12—C12 | 1.259 (4) | C211—F21 | 1.325 (6) |
| C11—C13 | 1.377 (5) | C221—F25 | 1.300 (5) |
| C11—C111 | 1.524 (5) | C221—F24 | 1.303 (5) |
| C12—C13 | 1.378 (5) | C221—F26 | 1.314 (5) |
| C12—C121 | 1.517 (5) | Mo3—O31 | 2.057 (2) |
| C13—H13 | 0.9500 | Mo3—O32 | 2.059 (2) |
| C111—F12 | 1.297 (4) | O31—C31 | 1.262 (4) |
| C111—F13 | 1.299 (4) | O32—C32 | 1.265 (4) |
| C111—F11 | 1.318 (5) | C31—C33 | 1.382 (5) |
| C121—F15 | 1.314 (4) | C31—C311 | 1.499 (6) |
| C121—F14 | 1.316 (5) | C32—C33 | 1.375 (5) |
| C121—F16 | 1.332 (4) | C32—C321 | 1.518 (5) |
| Mo2—O22 | 2.048 (2) | C33—H33 | 0.9500 |
| Mo2—O21 | 2.053 (2) | C311—F33 | 1.303 (5) |
| O21—C21 | 1.265 (4) | C311—F31 | 1.314 (6) |
| O22—C22 | 1.265 (4) | C311—F32 | 1.323 (5) |
| C21—C23 | 1.368 (5) | C321—F35 | 1.292 (5) |
| C21—C211 | 1.522 (5) | C321—F34 | 1.308 (6) |
| C22—C23 | 1.375 (5) | C321—F36 | 1.320 (6) |
| C22—C221 | 1.510 (6) | ||
| O12i—Mo1—O12 | 90.24 (9) | C21—C23—H23 | 118.4 |
| O12—Mo1—O11i | 88.97 (9) | C22—C23—H23 | 118.4 |
| O12i—Mo1—O11 | 176.92 (10) | F23—C211—F22 | 109.3 (4) |
| O12—Mo1—O11 | 86.78 (9) | F23—C211—F21 | 105.7 (4) |
| O11i—Mo1—O11 | 93.96 (9) | F22—C211—F21 | 107.1 (4) |
| C11—O11—Mo1 | 126.6 (2) | F23—C211—C21 | 112.7 (4) |
| C12—O12—Mo1 | 127.6 (2) | F22—C211—C21 | 112.2 (4) |
| O11—C11—C13 | 127.7 (3) | F21—C211—C21 | 109.6 (4) |
| O11—C11—C111 | 112.9 (3) | F25—C221—F24 | 107.7 (4) |
| C13—C11—C111 | 119.4 (3) | F25—C221—F26 | 108.2 (4) |
| O12—C12—C13 | 127.4 (3) | F24—C221—F26 | 105.2 (4) |
| O12—C12—C121 | 113.2 (3) | F25—C221—C22 | 112.5 (4) |
| C13—C12—C121 | 119.5 (4) | F24—C221—C22 | 110.2 (4) |
| C11—C13—C12 | 123.2 (4) | F26—C221—C22 | 112.7 (4) |
| C11—C13—H13 | 118.4 | O31iii—Mo3—O31 | 91.55 (10) |
| C12—C13—H13 | 118.4 | O31—Mo3—O32iii | 88.04 (10) |
| F12—C111—F13 | 108.3 (4) | O31iii—Mo3—O32 | 178.54 (11) |
| F12—C111—F11 | 106.1 (4) | O31—Mo3—O32 | 87.06 (10) |
| F13—C111—F11 | 106.9 (4) | O32—Mo3—O32ii | 93.33 (9) |
| F12—C111—C11 | 112.2 (3) | C31—O31—Mo3 | 127.5 (2) |
| F13—C111—C11 | 113.3 (3) | C32—O32—Mo3 | 126.5 (2) |
| F11—C111—C11 | 109.6 (3) | O31—C31—C33 | 127.4 (4) |
| F15—C121—F14 | 107.9 (4) | O31—C31—C311 | 113.0 (4) |
| F15—C121—F16 | 107.0 (3) | C33—C31—C311 | 119.6 (4) |
| F14—C121—F16 | 107.0 (3) | O32—C32—C33 | 128.5 (4) |
| F15—C121—C12 | 112.9 (3) | O32—C32—C321 | 112.3 (4) |
| F14—C121—C12 | 110.7 (4) | C33—C32—C321 | 119.2 (4) |
| F16—C121—C12 | 111.1 (3) | C32—C33—C31 | 122.9 (4) |
| O22—Mo2—O22ii | 91.41 (10) | C32—C33—H33 | 118.6 |
| O22—Mo2—O21iii | 88.26 (10) | C31—C33—H33 | 118.6 |
| O22—Mo2—O21 | 87.18 (10) | F33—C311—F31 | 106.3 (4) |
| O21iii—Mo2—O21 | 93.14 (9) | F33—C311—F32 | 108.5 (4) |
| O22—Mo2—O21ii | 178.54 (10) | F31—C311—F32 | 105.9 (4) |
| C21—O21—Mo2 | 126.6 (2) | F33—C311—C31 | 112.4 (4) |
| C22—O22—Mo2 | 127.2 (2) | F31—C311—C31 | 110.4 (4) |
| O21—C21—C23 | 128.2 (4) | F32—C311—C31 | 112.9 (4) |
| O21—C21—C211 | 112.3 (4) | F35—C321—F34 | 109.1 (5) |
| C23—C21—C211 | 119.5 (4) | F35—C321—F36 | 107.6 (4) |
| O22—C22—C23 | 127.6 (4) | F34—C321—F36 | 104.3 (4) |
| O22—C22—C221 | 112.7 (4) | F35—C321—C32 | 113.0 (4) |
| C23—C22—C221 | 119.7 (4) | F34—C321—C32 | 110.0 (4) |
| C21—C23—C22 | 123.1 (4) | F36—C321—C32 | 112.5 (4) |
| Symmetry codes: (i) −y+2, x−y+1, z; (ii) −x+y, −x+1, z; (iii) −y+1, x−y+1, z. |
| Complex | M—O (mean value) | M—O—M (mean value) | O···O |
| [Mo(hfacac)3]a | 2.053 (4) | 87.01 (9) | 2.829 (4) |
| [Mo(acac)3]b | 2.072 (3) | 87.4 (1) | 2.866 (3) |
| [Cr(hfacac)3]c | 1.957 (1) | 90.63 (5) | 2.782 (2) |
| [Cr(hfacac)3]d | 1.949 (5) | 90.8 (2) | 2.776 (7) |
| Notes: (a) This work; (b) Raston & White (1979); (c) Jessop et al. (2002); (d) Harada & Girolami (2007). acac is acetylacetonate and hfacac is 1,1,1,5,5,5-hexafluoroacetylacetonate. |
The authors acknowledge financial support from the CNRS and from the ANR (contract No. NT05–2_42140).
Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115–119.
Burnett, M. N. & Johnson, C. K. (1996). ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA.
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.
Harada, Y. & Girolami, G. S. (2007). Polyhedron, 26, 1758–1762.
Jessop, P. G., Olmstead, M. M., Ablan, C. D., Grabenauer, M., Sheppard, D., Eckert, C. A. & Liotta, C. L. (2002). Inorg. Chem. 41, 3463–3468.
Larsen, E. M. & Sukup, J. L. (1980). Synth. React. Inorg. Met. Org. Chem. 10, 601–606.
Oxford Diffraction (2008). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd., Abingdon, England.
Raston, C. L. & White, A. H. (1979). Aust. J. Chem. 32, 507–512.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.
Spek, A. L. (2009). Acta Cryst. D65, 148–155.
The title compound was of interest in our laboratory for potential application as reversible trapping agent of polymeric radical chains in controlled radical polymerization processes.
The stucture of the title compound, (I), is built up from three independent molybdenum centers located on two different three fold axes. As usually observed in such complexes (Raston & White, 1979; Jessop et al., 2002; Harada & Girolami, 2007) each molybdenum is surrounded by three chelating hexafluoroacetylacetonate ligands in a three-bladed propellor-like arrangement (Fig.1). The three molecules are roughly identical as can be seen from the molecular fitting views (Fig. 2) realized using PLATON (Spek, 2009) , they only differ by slight change in orientation. The metal-O bonds and O—M—O bond angles within the chelating β-diketonate framework compare with related complexes (Table 1), the observed difference in M—O bond length being related to the diffrence in the covalent radii between Cr (1.39 (5) Å) and Mo (1.54 Å).
This compound appears to be isostructural with the related chromium complex (Harada & Girolami, 2007) although the space groups are different, P -3 for the title complex whereas it is reported as P -3c1 for the chromium complex. Both crystals are twinned by merohedry by the same twin law but the symmetry of the Laue group in which it operates is different: -3 to -3 m for the title complex whereas it is -3 m to 6/mmm for the Cr complex. The refinement of the title complex is much better than the one reported for the Cr complex (Harada & Girolami, 2007).