metal-organic compounds
trans-Tetrakis(4-methylpyridine-κN)dioxidorhenium(V) hexafluoridophosphate
aResearch Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-34 Ookayama, Meguro-ku, Tokyo 152-8550, Japan
*Correspondence e-mail: yikeda@nr.titech.ac.jp
The title compound, [ReO2(C6H7N)4]PF6, contains octahedral [ReO2(4-Mepy)4]+ cations (4-Mepy is 4-methylpyridine) and PF6− anions. Both the cation and the anion reside on special positions, the Re atom on a crystallographic center of inversion and the P atom on a C2 axis parallel to the b axis. The ReV atom in the cation exhibits an octahedral coordination geometry with two O atoms in the apical positions and four N atoms of the 4-Mepy ligands in the equatorial plane. The Re=O and Re—N bond lengths fall in the typical ranges of trans-dioxidorhenium(V) complexes.
Related literature
For rhenium(V) complexes as radiopharmaceuticals, see: Dilworth & Parrott (1998); Volkert & Hoffman (1999). trans-Dioxidorhenium(V) ReO2+ complexes exhibit interesting properties as redox- and photo-active catalysts, see: Grey et al. (2004); Pipes & Meyer (1985); Thorp et al. (1989). For the synthesis of the title compound, see: Brewer & Gray (1989). For the crystal structures of trans-dioxidorhenium(V) complexes, see: Bélanger & Beauchamp (1996); Canlier et al. (2010); Gancheff et al. (2006); Kochel (2006); Kremer et al. (1996); Machura et al. (2008); Luck & O'Neill (2001); Reddy et al. (1999); Siczek et al. (2009).
Experimental
Crystal data
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Refinement
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Data collection: PROCESS-AUTO (Rigaku, 2006); cell PROCESS-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (CrystalMaker, 2007); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2006).
Supporting information
10.1107/S160053681002458X/zq2045sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S160053681002458X/zq2045Isup2.hkl
The title complex was synthesized according to the literature method by Brewer & Gray (Brewer & Gray, 1989). [ReO2(PPh3)2]I was reacted with 4-Mepy in methanol and the resulting [ReO2(4-Mepy)4]I was reacted with NH4PF6 in methanol.
All H atoms were positionated geometrically, with C—H = 0.95 and 0.98 Å for aromatic and methyl H atoms, respectively, and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).
Data collection: PROCESS-AUTO (Rigaku, 2006); cell
PROCESS-AUTO (Rigaku, 2006); data reduction: CrystalStructure (Rigaku/MSC, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (CrystalMaker, 2007); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2006).[ReO2(C6H7N)4]PF6 | F(000) = 1440.00 |
Mr = 735.68 | Dx = 1.796 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71075 Å |
Hall symbol: -C 2yc | Cell parameters from 13289 reflections |
a = 10.4914 (4) Å | θ = 3.1–27.4° |
b = 19.5359 (8) Å | µ = 4.60 mm−1 |
c = 14.0923 (5) Å | T = 173 K |
β = 109.5810 (11)° | Block, orange |
V = 2721.31 (18) Å3 | 0.26 × 0.13 × 0.12 mm |
Z = 4 |
Rigaku R-AXIS RAPID diffractometer | 3113 independent reflections |
Radiation source: fine-focus sealed tube | 2556 reflections with F2 > 2σ(F2) |
Graphite monochromator | Rint = 0.021 |
Detector resolution: 10.00 pixels mm-1 | θmax = 27.4° |
ω scans | h = −12→13 |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | k = −25→25 |
Tmin = 0.354, Tmax = 0.576 | l = −18→18 |
12743 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.022 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.044 | H-atom parameters constrained |
S = 1.16 | w = 1/[σ2(Fo2) + (0.0157P)2 + 6.0203P] where P = (Fo2 + 2Fc2)/3 |
3113 reflections | (Δ/σ)max < 0.001 |
175 parameters | Δρmax = 0.46 e Å−3 |
0 restraints | Δρmin = −0.39 e Å−3 |
Primary atom site location: structure-invariant direct methods |
[ReO2(C6H7N)4]PF6 | V = 2721.31 (18) Å3 |
Mr = 735.68 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 10.4914 (4) Å | µ = 4.60 mm−1 |
b = 19.5359 (8) Å | T = 173 K |
c = 14.0923 (5) Å | 0.26 × 0.13 × 0.12 mm |
β = 109.5810 (11)° |
Rigaku R-AXIS RAPID diffractometer | 3113 independent reflections |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | 2556 reflections with F2 > 2σ(F2) |
Tmin = 0.354, Tmax = 0.576 | Rint = 0.021 |
12743 measured reflections |
R[F2 > 2σ(F2)] = 0.022 | 0 restraints |
wR(F2) = 0.044 | H-atom parameters constrained |
S = 1.16 | Δρmax = 0.46 e Å−3 |
3113 reflections | Δρmin = −0.39 e Å−3 |
175 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Re1 | 0.7500 | 0.2500 | 0.5000 | 0.02256 (4) | |
P1 | 0.5000 | 0.04791 (6) | 0.7500 | 0.0334 (2) | |
F1 | 0.5776 (2) | 0.10485 (15) | 0.8276 (2) | 0.0838 (8) | |
F2 | 0.6185 (2) | 0.04807 (14) | 0.70289 (19) | 0.0670 (6) | |
F3 | 0.4238 (3) | −0.00954 (16) | 0.6730 (2) | 0.0962 (10) | |
O1 | 0.90491 (19) | 0.29340 (10) | 0.52054 (14) | 0.0268 (4) | |
N1 | 0.7527 (2) | 0.27819 (12) | 0.64789 (17) | 0.0257 (4) | |
N2 | 0.8575 (2) | 0.15747 (12) | 0.55935 (16) | 0.0249 (4) | |
C1 | 0.6844 (3) | 0.24197 (16) | 0.6970 (2) | 0.0311 (6) | |
C2 | 0.6861 (3) | 0.25974 (15) | 0.7926 (2) | 0.0331 (6) | |
C3 | 0.7583 (3) | 0.31654 (15) | 0.8417 (2) | 0.0311 (6) | |
C4 | 0.8272 (3) | 0.35354 (15) | 0.7905 (2) | 0.0319 (6) | |
C5 | 0.8225 (2) | 0.33362 (15) | 0.6953 (2) | 0.0294 (5) | |
C6 | 0.7652 (3) | 0.33635 (18) | 0.9466 (2) | 0.0440 (8) | |
C7 | 0.9942 (3) | 0.15588 (16) | 0.5950 (2) | 0.0331 (6) | |
C8 | 1.0667 (3) | 0.09651 (17) | 0.6268 (2) | 0.0372 (6) | |
C9 | 1.0011 (3) | 0.03451 (16) | 0.6232 (2) | 0.0323 (6) | |
C10 | 0.8602 (3) | 0.03686 (16) | 0.5894 (2) | 0.0365 (6) | |
C11 | 0.7926 (3) | 0.09779 (15) | 0.5586 (2) | 0.0313 (6) | |
C12 | 1.0782 (3) | −0.03129 (17) | 0.6533 (2) | 0.0418 (7) | |
H1 | 0.6337 | 0.2031 | 0.6650 | 0.037* | |
H2 | 0.6373 | 0.2328 | 0.8249 | 0.040* | |
H4 | 0.8780 | 0.3928 | 0.8209 | 0.038* | |
H5 | 0.8704 | 0.3600 | 0.6617 | 0.035* | |
H6A | 0.7107 | 0.3044 | 0.9706 | 0.053* | |
H6B | 0.7299 | 0.3829 | 0.9458 | 0.053* | |
H6C | 0.8594 | 0.3347 | 0.9916 | 0.053* | |
H7 | 1.0423 | 0.1975 | 0.5982 | 0.040* | |
H8 | 1.1628 | 0.0981 | 0.6514 | 0.045* | |
H10 | 0.8102 | −0.0040 | 0.5876 | 0.044* | |
H11 | 0.6965 | 0.0977 | 0.5360 | 0.038* | |
H12A | 1.0144 | −0.0693 | 0.6453 | 0.050* | |
H12B | 1.1370 | −0.0284 | 0.7238 | 0.050* | |
H12C | 1.1334 | −0.0391 | 0.6103 | 0.050* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Re1 | 0.01850 (7) | 0.02494 (7) | 0.02294 (7) | −0.00157 (8) | 0.00521 (5) | 0.00297 (7) |
P1 | 0.0302 (5) | 0.0239 (5) | 0.0474 (6) | 0.0000 | 0.0145 (4) | 0.0000 |
F1 | 0.0809 (19) | 0.0820 (19) | 0.0810 (18) | −0.0331 (15) | 0.0174 (14) | −0.0387 (15) |
F2 | 0.0484 (13) | 0.0881 (18) | 0.0769 (15) | −0.0047 (12) | 0.0375 (12) | 0.0053 (14) |
F3 | 0.095 (2) | 0.084 (2) | 0.127 (2) | −0.0475 (17) | 0.0597 (19) | −0.0657 (18) |
O1 | 0.0204 (9) | 0.0301 (10) | 0.0288 (9) | −0.0027 (7) | 0.0066 (7) | 0.0020 (8) |
N1 | 0.0213 (11) | 0.0257 (10) | 0.0284 (11) | 0.0004 (9) | 0.0062 (9) | 0.0022 (9) |
N2 | 0.0233 (11) | 0.0277 (11) | 0.0229 (10) | −0.0007 (9) | 0.0065 (8) | 0.0027 (8) |
C1 | 0.0310 (13) | 0.0327 (16) | 0.0304 (13) | −0.0047 (12) | 0.0110 (10) | 0.0022 (12) |
C2 | 0.0357 (15) | 0.0348 (18) | 0.0317 (13) | 0.0025 (12) | 0.0150 (11) | 0.0065 (12) |
C3 | 0.0330 (15) | 0.0319 (15) | 0.0272 (13) | 0.0116 (12) | 0.0084 (11) | 0.0046 (11) |
C4 | 0.0310 (15) | 0.0281 (14) | 0.0333 (14) | 0.0021 (12) | 0.0062 (11) | −0.0013 (11) |
C5 | 0.0275 (14) | 0.0303 (14) | 0.0295 (13) | −0.0015 (11) | 0.0084 (11) | 0.0029 (11) |
C6 | 0.063 (2) | 0.0379 (17) | 0.0343 (16) | 0.0082 (16) | 0.0204 (15) | 0.0007 (13) |
C7 | 0.0248 (14) | 0.0338 (15) | 0.0378 (15) | −0.0013 (12) | 0.0066 (11) | 0.0063 (12) |
C8 | 0.0242 (14) | 0.0424 (17) | 0.0413 (16) | 0.0057 (13) | 0.0062 (12) | 0.0076 (13) |
C9 | 0.0362 (16) | 0.0335 (15) | 0.0267 (13) | 0.0085 (12) | 0.0099 (11) | 0.0030 (11) |
C10 | 0.0362 (16) | 0.0288 (15) | 0.0425 (16) | −0.0022 (13) | 0.0106 (13) | 0.0028 (12) |
C11 | 0.0250 (14) | 0.0326 (15) | 0.0344 (15) | −0.0008 (12) | 0.0073 (11) | 0.0039 (12) |
C12 | 0.0445 (19) | 0.0348 (17) | 0.0448 (18) | 0.0137 (14) | 0.0135 (14) | 0.0044 (14) |
Re1—O1 | 1.7688 (19) | C4—C5 | 1.382 (4) |
Re1—O1i | 1.7688 (19) | C7—C8 | 1.377 (4) |
Re1—N1 | 2.147 (2) | C8—C9 | 1.386 (4) |
Re1—N1i | 2.147 (2) | C9—C10 | 1.394 (4) |
Re1—N2 | 2.146 (2) | C9—C12 | 1.502 (4) |
Re1—N2i | 2.146 (2) | C10—C11 | 1.379 (4) |
P1—F1 | 1.581 (2) | C1—H1 | 0.950 |
P1—F1ii | 1.581 (2) | C2—H2 | 0.950 |
P1—F2 | 1.593 (2) | C4—H4 | 0.950 |
P1—F2ii | 1.593 (2) | C5—H5 | 0.950 |
P1—F3 | 1.579 (3) | C6—H6A | 0.980 |
P1—F3ii | 1.579 (3) | C6—H6B | 0.980 |
N1—C1 | 1.351 (4) | C6—H6C | 0.980 |
N1—C5 | 1.352 (3) | C7—H7 | 0.950 |
N2—C7 | 1.352 (3) | C8—H8 | 0.950 |
N2—C11 | 1.348 (3) | C10—H10 | 0.950 |
C1—C2 | 1.386 (4) | C11—H11 | 0.950 |
C2—C3 | 1.390 (3) | C12—H12A | 0.980 |
C3—C4 | 1.384 (4) | C12—H12B | 0.980 |
C3—C6 | 1.506 (4) | C12—H12C | 0.980 |
O1—Re1—O1i | 180.00 (12) | C2—C3—C6 | 122.2 (3) |
O1—Re1—N1 | 90.33 (9) | C4—C3—C6 | 121.1 (2) |
O1—Re1—N1i | 89.67 (9) | C3—C4—C5 | 120.3 (2) |
O1—Re1—N2 | 90.35 (8) | N1—C5—C4 | 122.9 (2) |
O1—Re1—N2i | 89.65 (8) | N2—C7—C8 | 122.8 (2) |
O1i—Re1—N1 | 89.67 (9) | C7—C8—C9 | 120.7 (2) |
O1i—Re1—N1i | 90.33 (9) | C8—C9—C10 | 116.2 (2) |
O1i—Re1—N2 | 89.65 (8) | C8—C9—C12 | 121.6 (2) |
O1i—Re1—N2i | 90.35 (8) | C10—C9—C12 | 122.2 (2) |
N1—Re1—N1i | 180.00 (12) | C9—C10—C11 | 120.7 (2) |
N1—Re1—N2 | 90.20 (8) | N2—C11—C10 | 122.6 (2) |
N1—Re1—N2i | 89.80 (8) | N1—C1—H1 | 119.0 |
N1i—Re1—N2 | 89.80 (8) | C2—C1—H1 | 119.0 |
N1i—Re1—N2i | 90.20 (8) | C1—C2—H2 | 119.6 |
N2—Re1—N2i | 180.00 (12) | C3—C2—H2 | 119.6 |
F1—P1—F1ii | 90.54 (15) | C3—C4—H4 | 119.9 |
F1—P1—F2 | 89.65 (15) | C5—C4—H4 | 119.9 |
F1—P1—F2ii | 90.19 (15) | N1—C5—H5 | 118.6 |
F1—P1—F3 | 179.37 (16) | C4—C5—H5 | 118.6 |
F1—P1—F3ii | 90.02 (14) | C3—C6—H6A | 109.5 |
F1ii—P1—F2 | 90.19 (15) | C3—C6—H6B | 109.5 |
F1ii—P1—F2ii | 89.65 (15) | C3—C6—H6C | 109.5 |
F1ii—P1—F3 | 90.02 (14) | H6A—C6—H6B | 109.5 |
FPii—P1—F3ii | 179.37 (14) | H6A—C6—H6C | 109.5 |
F2—P1—F2ii | 179.78 (16) | H6B—C6—H6C | 109.5 |
F2—P1—F3 | 90.06 (16) | N2—C7—H7 | 118.6 |
F2—P1—F3ii | 90.10 (16) | C8—C7—H7 | 118.6 |
F2ii—P1—F3 | 90.10 (16) | C7—C8—H8 | 119.6 |
F2ii—P1—F3ii | 90.06 (16) | C9—C8—H8 | 119.6 |
F3—P1—F3ii | 89.41 (16) | C9—C10—H10 | 119.6 |
Re1—N1—C1 | 121.74 (18) | C11—C10—H10 | 119.6 |
Re1—N1—C5 | 120.9 (2) | N2—C11—H11 | 118.7 |
C1—N1—C5 | 117.3 (2) | C10—C11—H11 | 118.7 |
Re1—N2—C7 | 121.15 (19) | C9—C12—H12A | 109.5 |
Re1—N2—C11 | 121.84 (18) | C9—C12—H12B | 109.5 |
C7—N2—C11 | 116.9 (2) | C9—C12—H12C | 109.5 |
N1—C1—C2 | 122.1 (2) | H12A—C12—H12B | 109.5 |
C1—C2—C3 | 120.8 (3) | H12A—C12—H12C | 109.5 |
C2—C3—C4 | 116.7 (2) | H12B—C12—H12C | 109.5 |
Symmetry codes: (i) −x+3/2, −y+1/2, −z+1; (ii) −x+1, y, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [ReO2(C6H7N)4]PF6 |
Mr | 735.68 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 173 |
a, b, c (Å) | 10.4914 (4), 19.5359 (8), 14.0923 (5) |
β (°) | 109.5810 (11) |
V (Å3) | 2721.31 (18) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 4.60 |
Crystal size (mm) | 0.26 × 0.13 × 0.12 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID diffractometer |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.354, 0.576 |
No. of measured, independent and observed [F2 > 2σ(F2)] reflections | 12743, 3113, 2556 |
Rint | 0.021 |
(sin θ/λ)max (Å−1) | 0.648 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.022, 0.044, 1.16 |
No. of reflections | 3113 |
No. of parameters | 175 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.46, −0.39 |
Computer programs: PROCESS-AUTO (Rigaku, 2006), CrystalStructure (Rigaku/MSC, 2006), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), CrystalMaker (CrystalMaker, 2007).
Re1—O1 | 1.7688 (19) | Re1—N2 | 2.146 (2) |
Re1—N1 | 2.147 (2) | ||
O1—Re1—O1i | 180.00 (12) | O1—Re1—N2 | 90.35 (8) |
O1—Re1—N1 | 90.33 (9) | N1—Re1—N2 | 90.20 (8) |
Symmetry code: (i) −x+3/2, −y+1/2, −z+1. |
Acknowledgements
This work was supported by the Japan Society for Promotion of Science (JSPS).
References
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Rhenium(V) complexes as radiopharmaceuticals for therapy and diagnosis continue to attract attention, because rhenium isotopes have suitable radionuclear properties for the applications, i.e., 186Re: Emax = 1.1 MeV for β-emission and Emax = 0.137 MeV for γ-emission with t1/2 = 90.6 h, 188Re: Emax = 2.1 MeV for β-emission and Emax = 0.155 MeV for γ-emission with t1/2 = 17 h (Dilworth & Parrott, 1998; Volkert & Hoffman, 1999). On the other hand, trans-dioxorhenium(V) ReO2+ complexes have been known to exhibit interesting properties as redox- and photo-active catalysts (Grey et al., 2004; Pipes & Meyer, 1985; Thorp et al.,1989). To our knowledge, the title compound of formula [ReO2(4-Mepy)4]+.PF6- (4-Mepy = 4-methylpyridine) (I) was already synthesized by Brewer & Gray (Brewer & Gray, 1989), but a crystallographic characterization has not been yet reported. In this article, we report the X-ray crystal structure of the title compound.
Complex I crystallized in the centrosymmetric space group C2/c. The crystal structure is constructed by the packing of [ReO2(4-Mepy)4]+ cations and octahedral PF6- anions as shown Figs. 1 and 2. The Re atom is located on a crystallographic center of inversion and the P atom lies on a C2 axis parallel to the b axis. The ReV atom in the cation exhibits an octahedral coordination geometry with two O atoms in the apical positions and four N atoms of the 4-Mepy ligands in the equatorial plane. The Re═O and Re—N bond lengths fall in the typical ranges of trans-dioxorhenium(V) complexes. No classical hydrogen bonds are observed in the crystal structure. The N1—Re1—N2 bond angle and all N—Re1═O angles are almost 90 °. The bond lengths of Re1—O1N, Re1—N1, and Re1—N2 are 1.769 (2), 2.147 (2) and 2.146 (2) Å, respectively. These values are similar to those found for other trans-dioxorhenium(V) complexes (Bélanger & Beauchamp, 1996; Canlier et al., 2010; Gancheff et al., 2006; Kochel, 2006; Kremer et al., 1996; Machura et al., 2008; Luck & O'Neill, 2001; Reddy et al., 1999; Siczek et al., 2009).