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Acta Crystallogr Sect E Struct Rep Online. 2010 March 1; 66(Pt 3): m299–m300.
Published online 2010 February 13. doi:  10.1107/S1600536810005489
PMCID: PMC2983654

Tris(1,1,1,5,5,5-hexa­fluoro-2,4-pentane­dionato-κ2 O,O′)molybdenum(III)

Abstract

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 An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi1.jpg c1. Both crystals are twinned by merohedry with the same twin law (An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi2.jpg An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi2.jpg0/010/00An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi2.jpg) in reciprocal space, but the symmetry of the Laue group in which it operates is different, An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi1.jpg to An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi1.jpg m for the title complex, and An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi1.jpg m to 6/mmm for the CrIII complex.

Related literature

For related Cr(hfac)3 structures (hfac is 1,1,1,5,5,5-hexa­fluoro­acetonate), see: Harada & Girolami (2007 [triangle]); Jessop et al. (2002 [triangle]). For a related Mo(acac)3 complex (acac is acetyl­acetonate), see: Raston & White (1979 [triangle]). For the synthetic procedure, see: Larsen & Sukup (1980 [triangle]).

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Object name is e-66-0m299-scheme1.jpg

Experimental

Crystal data

  • [Mo(C5HF6O2)3]
  • M r = 717.11
  • Trigonal, An external file that holds a picture, illustration, etc.
Object name is e-66-0m299-efi8.jpg
  • a = 18.4876 (10) Å
  • c = 11.5021 (7) Å
  • V = 3404.6 (3) Å3
  • Z = 6
  • Mo Kα radiation
  • μ = 0.76 mm−1
  • T = 180 K
  • 0.39 × 0.11 × 0.05 mm

Data collection

  • Oxford Diffraction XCALIBUR diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008 [triangle]) T min = 0.731, T max = 1.000
  • 26629 measured reflections
  • 4635 independent reflections
  • 2801 reflections with I > 2σ(I)
  • R int = 0.063

Refinement

  • R[F 2 > 2σ(F 2)] = 0.030
  • wR(F 2) = 0.068
  • S = 0.97
  • 4635 reflections
  • 362 parameters
  • H-atom parameters constrained
  • Δρmax = 0.78 e Å−3
  • Δρmin = −0.44 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2008 [triangle]); cell refinement: CrysAlis RED (Oxford Diffraction, 2008 [triangle]); data reduction: CrysAlis RED; program(s) used to solve structure: SIR97 (Altomare et al., 1999 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 [triangle]), ORTEP-3 for Windows (Farrugia, 1997 [triangle]) and PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Comparison of some geometric parameters (Å, °) within the chelating acetonate units of related compounds

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810005489/gk2257sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810005489/gk2257Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge financial support from the CNRS and from the ANR (contract No. NT05–2_42140).

supplementary crystallographic information

Comment

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).

Experimental

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.

Refinement

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).

Figures

Fig. 1.
View of the three symmetry-independent molecules of (I) with atom labeling scheme. Dispalcement ellipsoids are shown at the 30% probability level. H atoms are represented as small spheres of arbitrary radii. (a) Molecule 1 [symmetry codes: (i) -y + 2, ...
Fig. 2.
Molecular fitting of the three independent molecules: (a) molecular fitting of molecules 1 and 2; (b) molecular fitting of molecules 1 and 3; (c) molecular fitting of molecules 2 and 3.

Crystal data

[Mo(C5HF6O2)3]Dx = 2.099 Mg m3
Mr = 717.11Mo Kα radiation, λ = 0.71073 Å
Trigonal, P3Cell parameters from 8040 reflections
a = 18.4876 (10) Åθ = 2.8–32.1°
c = 11.5021 (7) ŵ = 0.76 mm1
V = 3404.6 (3) Å3T = 180 K
Z = 6Prism, dark green
F(000) = 20700.39 × 0.11 × 0.05 mm

Data collection

Oxford Diffraction XCALIBUR diffractometer4635 independent reflections
Radiation source: fine-focus sealed tube2801 reflections with I > 2σ(I)
graphiteRint = 0.063
Detector resolution: 8.2632 pixels mm-1θmax = 26.4°, θmin = 2.8°
ω and [var phi] scansh = −23→23
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008)k = −23→23
Tmin = 0.731, Tmax = 1.000l = −14→14
26629 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.030Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.068H-atom parameters constrained
S = 0.97w = 1/[σ2(Fo2) + (0.0279P)2] where P = (Fo2 + 2Fc2)/3
4635 reflections(Δ/σ)max = 0.001
362 parametersΔρmax = 0.78 e Å3
0 restraintsΔρmin = −0.44 e Å3

Special details

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.

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

xyzUiso*/Ueq
Mo11.00001.00000.22101 (5)0.02614 (14)
O110.92251 (14)1.02746 (14)0.12480 (19)0.0300 (6)
O120.89820 (15)0.92784 (14)0.3234 (2)0.0328 (6)
C110.8485 (2)1.0084 (2)0.1500 (3)0.0292 (9)
C120.8278 (2)0.9228 (2)0.3202 (3)0.0334 (9)
C130.8008 (2)0.9608 (2)0.2420 (3)0.0346 (10)
H130.74660.95370.25210.042*
C1110.8113 (3)1.0438 (3)0.0641 (4)0.0412 (10)
C1210.7685 (3)0.8663 (3)0.4136 (3)0.0429 (11)
F110.84649 (19)1.12517 (17)0.0790 (2)0.0781 (9)
F120.82575 (17)1.03301 (18)−0.0431 (2)0.0653 (8)
F130.73139 (16)1.01295 (19)0.0767 (2)0.0829 (10)
F140.74487 (16)0.78765 (16)0.3919 (2)0.0704 (8)
F150.70096 (14)0.87247 (17)0.4230 (2)0.0698 (9)
F160.80526 (14)0.88434 (15)0.51746 (18)0.0532 (7)
Mo20.33330.66671.02042 (5)0.03124 (15)
O210.39312 (16)0.77397 (15)0.92317 (19)0.0357 (6)
O220.28812 (16)0.72680 (17)1.1206 (2)0.0370 (6)
C210.3944 (2)0.8419 (2)0.9427 (3)0.0351 (10)
C220.3029 (2)0.8010 (3)1.1092 (3)0.0332 (10)
C230.3536 (3)0.8590 (2)1.0281 (3)0.0373 (10)
H230.36060.91351.03160.045*
C2110.4503 (4)0.9104 (3)0.8578 (4)0.0564 (12)
C2210.2561 (3)0.8234 (3)1.1961 (4)0.0548 (13)
F210.5295 (2)0.93326 (19)0.8780 (3)0.0991 (11)
F220.4346 (2)0.88536 (15)0.7498 (2)0.0870 (10)
F230.4454 (2)0.97810 (17)0.8698 (2)0.0875 (10)
F240.1770 (2)0.7858 (2)1.1699 (3)0.1105 (13)
F250.26262 (18)0.80214 (18)1.3017 (2)0.0743 (9)
F260.2806 (2)0.9036 (2)1.1958 (3)0.1124 (13)
Mo30.33330.66670.54730 (5)0.03462 (16)
O310.39271 (18)0.77270 (15)0.4469 (2)0.0403 (6)
O320.44118 (15)0.71545 (18)0.64445 (19)0.0377 (6)
C310.4665 (3)0.8327 (3)0.4578 (3)0.0385 (10)
C320.5086 (2)0.7827 (3)0.6246 (3)0.0367 (10)
C330.5252 (2)0.8409 (2)0.5390 (3)0.0377 (10)
H330.57930.88880.53560.045*
C3110.4891 (4)0.8998 (3)0.3686 (4)0.0582 (14)
C3210.5779 (3)0.7956 (4)0.7077 (4)0.0577 (13)
F310.4518 (2)0.94281 (18)0.3915 (3)0.0957 (11)
F320.56998 (19)0.95469 (18)0.3661 (2)0.0947 (11)
F330.46553 (18)0.86962 (17)0.2642 (2)0.0817 (10)
F340.6111 (2)0.7510 (3)0.6743 (3)0.1150 (13)
F350.55263 (14)0.7768 (2)0.8139 (2)0.0820 (9)
F360.64080 (17)0.8732 (2)0.7069 (3)0.0984 (12)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Mo10.02183 (17)0.02183 (17)0.0348 (3)0.01092 (9)0.0000.000
O110.0287 (15)0.0307 (15)0.0327 (15)0.0163 (13)0.0021 (12)0.0054 (11)
O120.0271 (15)0.0280 (15)0.0375 (16)0.0094 (12)−0.0027 (12)0.0045 (11)
C110.030 (2)0.031 (2)0.029 (2)0.017 (2)−0.0049 (19)−0.0059 (18)
C120.028 (2)0.030 (2)0.032 (2)0.007 (2)−0.0054 (17)−0.0056 (19)
C130.028 (2)0.046 (3)0.030 (2)0.019 (2)−0.0003 (19)−0.001 (2)
C1110.041 (3)0.055 (3)0.038 (3)0.031 (3)0.006 (2)0.007 (2)
C1210.035 (3)0.051 (3)0.032 (3)0.013 (2)−0.001 (2)0.005 (2)
F110.112 (3)0.058 (2)0.089 (2)0.061 (2)−0.0238 (18)−0.0026 (16)
F120.095 (2)0.102 (2)0.0347 (15)0.0761 (19)−0.0062 (14)0.0026 (14)
F130.0444 (17)0.129 (3)0.089 (2)0.0540 (18)0.0083 (15)0.0499 (19)
F140.072 (2)0.0407 (17)0.0615 (18)0.0002 (15)0.0110 (14)0.0096 (14)
F150.0354 (14)0.116 (3)0.0551 (16)0.0353 (15)0.0171 (12)0.0278 (15)
F160.0472 (14)0.0699 (18)0.0291 (13)0.0192 (14)−0.0013 (11)0.0068 (12)
Mo20.0247 (2)0.0247 (2)0.0442 (4)0.01237 (10)0.0000.000
O210.0316 (16)0.0292 (15)0.0412 (16)0.0112 (13)0.0095 (14)0.0001 (11)
O220.0373 (17)0.0328 (17)0.0435 (16)0.0195 (14)0.0119 (14)0.0073 (14)
C210.041 (3)0.028 (2)0.029 (2)0.011 (2)0.0001 (19)−0.0001 (19)
C220.039 (2)0.040 (3)0.030 (2)0.027 (2)−0.0014 (19)0.000 (2)
C230.053 (3)0.032 (2)0.033 (2)0.026 (2)0.003 (2)−0.002 (2)
C2110.068 (4)0.038 (3)0.044 (3)0.013 (3)0.020 (3)0.010 (2)
C2210.068 (4)0.066 (3)0.051 (3)0.048 (3)0.011 (3)0.007 (3)
F210.066 (2)0.067 (2)0.120 (3)−0.0003 (18)0.031 (2)0.0258 (19)
F220.141 (3)0.0547 (16)0.0318 (15)0.024 (2)0.0277 (18)0.0060 (12)
F230.152 (3)0.0401 (17)0.0640 (19)0.0431 (19)0.0365 (18)0.0197 (14)
F240.074 (2)0.199 (4)0.098 (2)0.098 (3)0.006 (2)−0.024 (2)
F250.113 (2)0.113 (2)0.0348 (16)0.086 (2)0.0201 (15)0.0130 (15)
F260.203 (4)0.091 (2)0.095 (2)0.112 (3)0.065 (2)0.0199 (19)
Mo30.0314 (2)0.0314 (2)0.0411 (4)0.01569 (11)0.0000.000
O310.0419 (18)0.0353 (15)0.0406 (16)0.0170 (16)−0.0086 (15)0.0052 (12)
O320.0329 (15)0.0398 (17)0.0394 (16)0.0175 (15)0.0020 (12)0.0113 (14)
C310.050 (3)0.035 (3)0.031 (3)0.021 (2)−0.001 (2)0.001 (2)
C320.030 (2)0.049 (3)0.032 (2)0.020 (2)0.0040 (19)0.007 (2)
C330.032 (2)0.042 (3)0.031 (2)0.012 (2)0.0044 (19)0.005 (2)
C3110.071 (4)0.040 (3)0.045 (3)0.014 (3)−0.012 (3)0.007 (3)
C3210.037 (3)0.082 (4)0.048 (3)0.026 (3)−0.001 (2)0.016 (3)
F310.148 (3)0.067 (2)0.096 (2)0.072 (2)−0.003 (2)0.0206 (17)
F320.079 (2)0.068 (2)0.087 (2)0.0004 (19)−0.0146 (18)0.0430 (17)
F330.114 (3)0.0654 (19)0.0379 (16)0.0244 (18)−0.0140 (16)0.0115 (14)
F340.097 (3)0.183 (4)0.117 (3)0.108 (3)−0.030 (2)−0.012 (3)
F350.0481 (15)0.124 (3)0.0445 (16)0.0212 (19)−0.0042 (12)0.0350 (19)
F360.0482 (18)0.103 (3)0.083 (2)−0.0081 (19)−0.0228 (16)0.0361 (19)

Geometric parameters (Å, °)

Mo1—O122.049 (2)C23—H230.9500
Mo1—O112.064 (2)C211—F231.306 (5)
O11—C111.265 (4)C211—F221.306 (5)
O12—C121.259 (4)C211—F211.325 (6)
C11—C131.377 (5)C221—F251.300 (5)
C11—C1111.524 (5)C221—F241.303 (5)
C12—C131.378 (5)C221—F261.314 (5)
C12—C1211.517 (5)Mo3—O312.057 (2)
C13—H130.9500Mo3—O322.059 (2)
C111—F121.297 (4)O31—C311.262 (4)
C111—F131.299 (4)O32—C321.265 (4)
C111—F111.318 (5)C31—C331.382 (5)
C121—F151.314 (4)C31—C3111.499 (6)
C121—F141.316 (5)C32—C331.375 (5)
C121—F161.332 (4)C32—C3211.518 (5)
Mo2—O222.048 (2)C33—H330.9500
Mo2—O212.053 (2)C311—F331.303 (5)
O21—C211.265 (4)C311—F311.314 (6)
O22—C221.265 (4)C311—F321.323 (5)
C21—C231.368 (5)C321—F351.292 (5)
C21—C2111.522 (5)C321—F341.308 (6)
C22—C231.375 (5)C321—F361.320 (6)
C22—C2211.510 (6)
O12i—Mo1—O1290.24 (9)C21—C23—H23118.4
O12—Mo1—O11i88.97 (9)C22—C23—H23118.4
O12i—Mo1—O11176.92 (10)F23—C211—F22109.3 (4)
O12—Mo1—O1186.78 (9)F23—C211—F21105.7 (4)
O11i—Mo1—O1193.96 (9)F22—C211—F21107.1 (4)
C11—O11—Mo1126.6 (2)F23—C211—C21112.7 (4)
C12—O12—Mo1127.6 (2)F22—C211—C21112.2 (4)
O11—C11—C13127.7 (3)F21—C211—C21109.6 (4)
O11—C11—C111112.9 (3)F25—C221—F24107.7 (4)
C13—C11—C111119.4 (3)F25—C221—F26108.2 (4)
O12—C12—C13127.4 (3)F24—C221—F26105.2 (4)
O12—C12—C121113.2 (3)F25—C221—C22112.5 (4)
C13—C12—C121119.5 (4)F24—C221—C22110.2 (4)
C11—C13—C12123.2 (4)F26—C221—C22112.7 (4)
C11—C13—H13118.4O31iii—Mo3—O3191.55 (10)
C12—C13—H13118.4O31—Mo3—O32iii88.04 (10)
F12—C111—F13108.3 (4)O31iii—Mo3—O32178.54 (11)
F12—C111—F11106.1 (4)O31—Mo3—O3287.06 (10)
F13—C111—F11106.9 (4)O32—Mo3—O32ii93.33 (9)
F12—C111—C11112.2 (3)C31—O31—Mo3127.5 (2)
F13—C111—C11113.3 (3)C32—O32—Mo3126.5 (2)
F11—C111—C11109.6 (3)O31—C31—C33127.4 (4)
F15—C121—F14107.9 (4)O31—C31—C311113.0 (4)
F15—C121—F16107.0 (3)C33—C31—C311119.6 (4)
F14—C121—F16107.0 (3)O32—C32—C33128.5 (4)
F15—C121—C12112.9 (3)O32—C32—C321112.3 (4)
F14—C121—C12110.7 (4)C33—C32—C321119.2 (4)
F16—C121—C12111.1 (3)C32—C33—C31122.9 (4)
O22—Mo2—O22ii91.41 (10)C32—C33—H33118.6
O22—Mo2—O21iii88.26 (10)C31—C33—H33118.6
O22—Mo2—O2187.18 (10)F33—C311—F31106.3 (4)
O21iii—Mo2—O2193.14 (9)F33—C311—F32108.5 (4)
O22—Mo2—O21ii178.54 (10)F31—C311—F32105.9 (4)
C21—O21—Mo2126.6 (2)F33—C311—C31112.4 (4)
C22—O22—Mo2127.2 (2)F31—C311—C31110.4 (4)
O21—C21—C23128.2 (4)F32—C311—C31112.9 (4)
O21—C21—C211112.3 (4)F35—C321—F34109.1 (5)
C23—C21—C211119.5 (4)F35—C321—F36107.6 (4)
O22—C22—C23127.6 (4)F34—C321—F36104.3 (4)
O22—C22—C221112.7 (4)F35—C321—C32113.0 (4)
C23—C22—C221119.7 (4)F34—C321—C32110.0 (4)
C21—C23—C22123.1 (4)F36—C321—C32112.5 (4)

Symmetry codes: (i) −y+2, xy+1, z; (ii) −x+y, −x+1, z; (iii) −y+1, xy+1, z.

Table 1 Comparison of some geometric parameters (Å, °) within the chelating acetonate units of related compounds

ComplexM—O (mean value)M—O—M (mean value)O···O
[Mo(hfacac)3]a2.053 (4)87.01 (9)2.829 (4)
[Mo(acac)3]b2.072 (3)87.4 (1)2.866 (3)
[Cr(hfacac)3]c1.957 (1)90.63 (5)2.782 (2)
[Cr(hfacac)3]d1.949 (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.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: GK2257).

References

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