Acta Cryst. (2007). E63, m2422 [ doi:10.1107/S1600536807039323 ]
The crystal structure of the title compound, [VO(C5H7O2)2(C5H5N)], has been reported previously [Meicheng, Lifeng & Youqi (1984). Kexue Tongbao, 29, 759-764], with an R value of 0.13. The current redetermination shows a significant improvement in the precision of the geometric parameters. The V atom binds five O atoms and one N atom from the pyridine ligand in a distorted octahedral configuration; the acetylacetonate anions act as bidentate ligands. A crystallographic twofold axis passes through the V, vanadyl O, and pyridine N and para-C atoms.
The title compound was synthesized by refluxing VO(acac)2 (1.00 g, 3.68 mmol) dissolved pyridine (15 ml) for 2 h. After cooling to room temperature, 80 ml of diethyl ether was added. Light green single crystals of the compound were obtained by slow evaporation of the solution at room temperature over several days in a dessecator. Yield (crystals): 0.13 g (10.15%).
All H atoms on were refined using a riding model, with C—H = 0.93 Å and Uiso(H) = 1.2Ueq(C) for the methine C atoms and C—H = 0.96 Å and Uiso = 1.5Ueq(C) for the methyl C atoms.
Data collection: APEX2, COSMO and BIS (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 2007); software used to prepare material for publication: SHELXL97.
![[Figure 1]](./lh2476fig1thm.gif)
| Fig. 1. The molecular structure with 30% probability ellipsoids. [Symmetry code: (i) 1 − x, y, 1.5 − z.] |
![[Figure 2]](./lh2476fig2thm.gif)
| Fig. 2. Part of the crytal structure viewed perpendicular to the bc plane. The phenyl groups are represented as solid grey lines. Hydrogen atoms omitted for sake of clarity. |
| [V(C5H7O2)2O(C5H5N)] | F000 = 716 |
| Mr = 344.25 | Dx = 1.344 Mg m−3 |
| Monoclinic, C2/c | Mo Kα radiation λ = 0.71073 Å |
| Hall symbol: -C 2yc | Cell parameters from 2628 reflections |
| a = 7.9121 (3) Å | θ = 2.9–24.1º |
| b = 15.5258 (7) Å | µ = 0.60 mm−1 |
| c = 14.2523 (6) Å | T = 296 (2) K |
| β = 103.621 (3)º | Trapezoid, blue–green |
| V = 1701.54 (12) Å3 | 0.35 × 0.35 × 0.25 mm |
| Z = 4 |
| Bruker APEX II area-detector diffractometer | 1837 reflections with I > 2σ(I) |
| Monochromator: graphite | Rint = 0.032 |
| T = 296(2) K | θmax = 30.4º |
| φ and ω scans | θmin = 2.9º |
| Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −11→11 |
| Tmin = 0.903, Tmax = 1 | k = −22→20 |
| 11650 measured reflections | l = −20→20 |
| 2595 independent reflections |
| Refinement on F2 | Secondary atom site location: difference Fourier map |
| Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
| R[F2 > 2σ(F2)] = 0.039 | H-atom parameters constrained |
| wR(F2) = 0.116 | w = 1/[σ2(Fo2) + (0.0608P)2 + 0.0762P] where P = (Fo2 + 2Fc2)/3 |
| S = 1.05 | (Δ/σ)max = 0.001 |
| 2595 reflections | Δρmax = 0.23 e Å−3 |
| 104 parameters | Δρmin = −0.31 e Å−3 |
| Primary atom site location: structure-invariant direct methods | Extinction correction: none |
| [V(C5H7O2)2O(C5H5N)] | V = 1701.54 (12) Å3 |
| Mr = 344.25 | Z = 4 |
| Monoclinic, C2/c | Mo Kα |
| a = 7.9121 (3) Å | µ = 0.60 mm−1 |
| b = 15.5258 (7) Å | T = 296 (2) K |
| c = 14.2523 (6) Å | 0.35 × 0.35 × 0.25 mm |
| β = 103.621 (3)º |
| Bruker APEX II area-detector diffractometer | 2595 independent reflections |
| Absorption correction: multi-scan (SADABS; Bruker, 2006) | 1837 reflections with I > 2σ(I) |
| Tmin = 0.903, Tmax = 1 | Rint = 0.032 |
| 11650 measured reflections |
| R[F2 > 2σ(F2)] = 0.039 | 104 parameters |
| wR(F2) = 0.116 | H-atom parameters constrained |
| S = 1.05 | Δρmax = 0.23 e Å−3 |
| 2595 reflections | Δρmin = −0.31 e Å−3 |
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 > 2sigma(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 | ||
| C1 | 0.8337 (2) | 0.61290 (12) | 0.88998 (13) | 0.0543 (4) | |
| C2 | 0.7518 (2) | 0.62217 (15) | 0.96641 (14) | 0.0663 (5) | |
| H2 | 0.8226 | 0.6322 | 1.0275 | 0.08* | |
| C3 | 0.5742 (2) | 0.61768 (12) | 0.95867 (12) | 0.0525 (4) | |
| C4 | 1.0287 (2) | 0.61760 (18) | 0.91047 (17) | 0.0838 (7) | |
| H4A | 1.0753 | 0.5607 | 0.9086 | 0.126* | |
| H4B | 1.0731 | 0.6421 | 0.9733 | 0.126* | |
| H4C | 1.0623 | 0.6529 | 0.8627 | 0.126* | |
| C5 | 0.5044 (3) | 0.62994 (17) | 1.04695 (13) | 0.0761 (6) | |
| H5A | 0.4164 | 0.6738 | 1.0348 | 0.114* | |
| H5B | 0.5972 | 0.647 | 1.1001 | 0.114* | |
| H5C | 0.4551 | 0.5768 | 1.0624 | 0.114* | |
| C6 | 0.6215 (2) | 0.78243 (13) | 0.71999 (13) | 0.0592 (5) | |
| H6 | 0.707 | 0.7525 | 0.6985 | 0.071* | |
| C7 | 0.6260 (3) | 0.87100 (15) | 0.71941 (14) | 0.0755 (6) | |
| H7 | 0.7133 | 0.9 | 0.6985 | 0.091* | |
| C8 | 0.5 | 0.91579 (19) | 0.75 | 0.0835 (10) | |
| H8 | 0.5 | 0.9757 | 0.75 | 0.1* | |
| N1 | 0.5 | 0.73721 (13) | 0.75 | 0.0495 (4) | |
| O1 | 0.5 | 0.47833 (11) | 0.75 | 0.0607 (4) | |
| O2 | 0.46038 (14) | 0.60333 (8) | 0.88081 (8) | 0.0530 (3) | |
| O3 | 0.75487 (14) | 0.59983 (9) | 0.80249 (9) | 0.0544 (3) | |
| V1 | 0.5 | 0.58123 (3) | 0.75 | 0.04534 (15) |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| C1 | 0.0421 (8) | 0.0563 (10) | 0.0592 (11) | 0.0013 (7) | 0.0014 (7) | −0.0033 (8) |
| C2 | 0.0509 (10) | 0.0910 (15) | 0.0500 (10) | −0.0003 (10) | −0.0018 (8) | −0.0085 (10) |
| C3 | 0.0576 (9) | 0.0538 (10) | 0.0444 (9) | 0.0013 (8) | 0.0087 (7) | 0.0035 (7) |
| C4 | 0.0411 (9) | 0.115 (2) | 0.0879 (16) | 0.0009 (11) | 0.0001 (9) | −0.0218 (14) |
| C5 | 0.0798 (14) | 0.1023 (18) | 0.0470 (10) | −0.0041 (13) | 0.0163 (9) | −0.0046 (10) |
| C6 | 0.0488 (9) | 0.0674 (12) | 0.0609 (11) | −0.0088 (8) | 0.0119 (8) | 0.0019 (9) |
| C7 | 0.0876 (15) | 0.0694 (15) | 0.0654 (13) | −0.0281 (12) | 0.0101 (10) | 0.0034 (10) |
| C8 | 0.126 (3) | 0.0495 (17) | 0.0649 (19) | 0 | 0.0016 (19) | 0 |
| N1 | 0.0413 (9) | 0.0547 (12) | 0.0520 (11) | 0 | 0.0101 (8) | 0 |
| O1 | 0.0631 (10) | 0.0560 (11) | 0.0623 (11) | 0 | 0.0133 (8) | 0 |
| O2 | 0.0448 (6) | 0.0710 (8) | 0.0430 (6) | −0.0021 (5) | 0.0095 (5) | 0.0021 (5) |
| O3 | 0.0360 (6) | 0.0735 (8) | 0.0519 (7) | 0.0035 (5) | 0.0069 (5) | −0.0015 (5) |
| V1 | 0.0375 (2) | 0.0560 (3) | 0.0412 (2) | 0 | 0.00648 (15) | 0 |
| C1—O3 | 1.272 (2) | C6—C7 | 1.376 (3) |
| C1—C2 | 1.400 (2) | C6—H6 | 0.93 |
| C1—C4 | 1.503 (2) | C7—C8 | 1.368 (3) |
| C2—C3 | 1.386 (2) | C7—H7 | 0.93 |
| C2—H2 | 0.93 | C8—C7i | 1.368 (3) |
| C3—O2 | 1.273 (2) | C8—H8 | 0.93 |
| C3—C5 | 1.500 (2) | N1—C6i | 1.339 (2) |
| C4—H4A | 0.96 | N1—V1 | 2.422 (2) |
| C4—H4B | 0.96 | O1—V1 | 1.5976 (18) |
| C4—H4C | 0.96 | O2—V1 | 1.9918 (11) |
| C5—H5A | 0.96 | O3—V1 | 1.9997 (11) |
| C5—H5B | 0.96 | V1—O2i | 1.9918 (11) |
| C5—H5C | 0.96 | V1—O3i | 1.9997 (11) |
| C6—N1 | 1.339 (2) | ||
| O3—C1—C2 | 124.71 (15) | C8—C7—H7 | 120.5 |
| O3—C1—C4 | 116.22 (16) | C6—C7—H7 | 120.5 |
| C2—C1—C4 | 119.06 (17) | C7i—C8—C7 | 118.9 (3) |
| C3—C2—C1 | 125.41 (17) | C7i—C8—H8 | 120.6 |
| C3—C2—H2 | 117.3 | C7—C8—H8 | 120.6 |
| C1—C2—H2 | 117.3 | C6—N1—C6i | 116.8 (2) |
| O2—C3—C2 | 125.04 (16) | C6—N1—V1 | 121.61 (11) |
| O2—C3—C5 | 115.39 (15) | C6i—N1—V1 | 121.61 (11) |
| C2—C3—C5 | 119.57 (16) | C3—O2—V1 | 127.66 (11) |
| C1—C4—H4A | 109.5 | C1—O3—V1 | 127.44 (11) |
| C1—C4—H4B | 109.5 | O1—V1—O2 | 99.92 (4) |
| H4A—C4—H4B | 109.5 | O1—V1—O2i | 99.92 (4) |
| C1—C4—H4C | 109.5 | O2—V1—O2i | 160.16 (8) |
| H4A—C4—H4C | 109.5 | O1—V1—O3 | 98.30 (4) |
| H4B—C4—H4C | 109.5 | O2—V1—O3 | 89.55 (5) |
| C3—C5—H5A | 109.5 | O2i—V1—O3 | 87.60 (5) |
| C3—C5—H5B | 109.5 | O1—V1—O3i | 98.30 (4) |
| H5A—C5—H5B | 109.5 | O2—V1—O3i | 87.60 (5) |
| C3—C5—H5C | 109.5 | O2i—V1—O3i | 89.55 (5) |
| H5A—C5—H5C | 109.5 | O3—V1—O3i | 163.39 (8) |
| H5B—C5—H5C | 109.5 | O1—V1—N1 | 180 |
| N1—C6—C7 | 123.16 (19) | O2—V1—N1 | 80.08 (4) |
| N1—C6—H6 | 118.4 | O2i—V1—N1 | 80.08 (4) |
| C7—C6—H6 | 118.4 | O3—V1—N1 | 81.70 (4) |
| C8—C7—C6 | 119.0 (2) | O3i—V1—N1 | 81.70 (4) |
| O3—C1—C2—C3 | 0.7 (4) | C3—O2—V1—O3i | −166.86 (15) |
| C4—C1—C2—C3 | −178.7 (2) | C3—O2—V1—N1 | −84.87 (15) |
| C1—C2—C3—O2 | 1.0 (4) | C1—O3—V1—O1 | −95.23 (15) |
| C1—C2—C3—C5 | −179.3 (2) | C1—O3—V1—O2 | 4.73 (15) |
| N1—C6—C7—C8 | −0.6 (3) | C1—O3—V1—O2i | 165.09 (15) |
| C6—C7—C8—C7i | 0.28 (12) | C1—O3—V1—O3i | 84.77 (15) |
| C7—C6—N1—C6i | 0.30 (13) | C1—O3—V1—N1 | 84.77 (15) |
| C7—C6—N1—V1 | −179.70 (13) | C6—N1—V1—O2 | 133.93 (10) |
| C2—C3—O2—V1 | 1.2 (3) | C6i—N1—V1—O2 | −46.07 (10) |
| C5—C3—O2—V1 | −178.52 (13) | C6—N1—V1—O2i | −46.07 (10) |
| C2—C1—O3—V1 | −4.3 (3) | C6i—N1—V1—O2i | 133.93 (10) |
| C4—C1—O3—V1 | 175.11 (14) | C6—N1—V1—O3 | 42.93 (10) |
| C3—O2—V1—O1 | 95.13 (15) | C6i—N1—V1—O3 | −137.07 (10) |
| C3—O2—V1—O2i | −84.87 (15) | C6—N1—V1—O3i | −137.07 (10) |
| C3—O2—V1—O3 | −3.22 (15) | C6i—N1—V1—O3i | 42.93 (10) |
| Symmetry codes: (i) −x+1, y, −z+3/2. |
| C1—O3 | 1.272 (2) | C3—C5 | 1.500 (2) |
| C1—C2 | 1.400 (2) | N1—V1 | 2.422 (2) |
| C1—C4 | 1.503 (2) | O1—V1 | 1.5976 (18) |
| C2—C3 | 1.386 (2) | O2—V1 | 1.9918 (11) |
| C3—O2 | 1.273 (2) | O3—V1 | 1.9997 (11) |
| O3—C1—C2 | 124.71 (15) | C1—O3—V1 | 127.44 (11) |
| O3—C1—C4 | 116.22 (16) | O1—V1—O2 | 99.92 (4) |
| C2—C1—C4 | 119.06 (17) | O2—V1—O2i | 160.16 (8) |
| C3—C2—C1 | 125.41 (17) | O1—V1—O3 | 98.30 (4) |
| O2—C3—C2 | 125.04 (16) | O2—V1—O3 | 89.55 (5) |
| O2—C3—C5 | 115.39 (15) | O2i—V1—O3 | 87.60 (5) |
| C2—C3—C5 | 119.57 (16) | O1—V1—N1 | 180 |
| C3—O2—V1 | 127.66 (11) |
| Symmetry codes: (i) −x+1, y, −z+3/2. |
RMSS thanks CAPES for a PhD schlolarship. The diffractomer was funded by a CT–INFRA grant from the Financiadora de Estudos e Projetos (FINEP), Brazil.
Allen, F. H. (2002). Acta Cryst. B58, 380–388.
Brandenburg, K. (2007). DIAMOND. Version 3.1e. Crystal Impact Gbr, Bonn, Germany.
Bruker (2006). APEX2 (Version 2.1), COSMO (Version 1.56), BIS (Version 2.0.1.9), SAINT (Version 7.34A) and SADABS (Version 2004/1). Bruker AXS Inc., Madison, Wisconsin, USA.
Meicheng, S., Lifeng, W. & Yougi, T. (1984). Kexue Tongbao, 29, 759–764.
Sheldrick, G. M. (1997). SHELXL97 and SHELXS97. University of Göttingen, Germany.
The crystal structure of the title compound, VO(C5H7O)2C5H5N, was determined previously by (Meicheng et al., 1984). The original structure refinement converged with R1 = 0.13 [CUCWUS; Cambridge Structural Database (CSD, Version 5.28, update of January 2007; Allen, 2002)]. The current redetermination shows a significant improvement in the precision of the geometric parameters. A low temperature experiment was attempted, but the crystal quickly powders under a cold nitrogen stream. One half-molecule is found in the asymmetric unit; the complete molecule is generated by a crystallographic 2 fold axis which passes through atoms O1, V1, N1 and C8. The geometry of the hexacoordinate V atom can be regarded as distorted octahedral with the two acetylacetonato ligands chelating in the equatorial plane, and the vandyl O and the pyridinal N atoms in axial positions (Fig. 1). The V1 atom is centered 0.3160 (10) Å out of the plane formed by four coordinated oxygen atoms, in the direction of the apical O1 atom. The V=O distance is 1.5976 (18) Å in good agreement with ranges observed for other VO5N octahedral found in the Cambridge Structural Database (CSD, Version 5.28, update of January 2007; Allen, 2002)] (V=O 1.598 (11) Å for 21 observations), the cisoid angles (O–V–O and O–V–N) being 80.08 (4) – 99.92 (4)°, and transoid angles (O–V–O and O–V–N) being 160.16 (8) – 180° (Table 1). The molecules packs around a crystallographic twofold screw axis, parallel to the crystallographic b-axis (Fig. 2).
The thermal gravimetric analysis (TGA) of 1 shows a loss of one molecule of pyridine (exp. 22.03%, calc. 22.97%) at 334.98 K, followed by the loss of C10H16O5(exp. 64.41%, calc. 62.23%)at 438.45 K. The residual weight for the whole process (exp. 13.56%, calc. 14.80%) is in good agreement assuming V as the final end product.