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Acta Crystallogr Sect E Struct Rep Online. 2008 December 1; 64(Pt 12): m1548–m1549.
Published online 2008 November 13. doi:  10.1107/S160053680803328X
PMCID: PMC2959960

A monoclinic polymorph of di-μ-oxido-bis­({2-[2-(methyl­amino)ethyl­imino­methyl]phenolato-κ3 N,N′,O}oxidovanadium(V))

Abstract

A new monoclinic polymorph of the title compound, [V2(C10H13N2O)2O4], which is a centrosymmetric dimer, crystallizes in space group P21/c, whereas the previously known polymorph crystallizes in the ortho­rhom­bic space group Pbca [Mokry & Carrano (1993 [triangle]). Inorg. Chem. 32, 6119–6121]. Each VV atom is six-coordinated by one oxide group, two N atoms and one O atom from the Schiff base ligand, and by two additional bridging O atoms. The two methyl­ene groups are each disordered over two sites, with occupancy factors of 0.776 (14) and 0.224 (14). In the crystal structure, there are C—H(...)O hydrogen bonds and C—H(...)π inter­actions between the dimers.

Related literature

For general background, see: Butler & Walker (1993 [triangle]); Carter-Franklin et al. (2003 [triangle]); Eady (2003 [triangle]); Evangelou (2002 [triangle]); Mendz (1991 [triangle]); Rehder et al. (2003 [triangle]); Sakurai (2002 [triangle]). For related structures, see: Mokry & Carrano (1993 [triangle]); Rao et al. (1981 [triangle]); Romanowski et al. (2008 [triangle]); Root et al. (1993 [triangle]). For the synthesis, see: Kwiatkowski et al. (2003 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-64-m1548-scheme1.jpg

Experimental

Crystal data

  • [V2(C10H13N2O)2O4]
  • M r = 520.33
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-64-m1548-efi2.jpg
  • a = 6.6801 (2) Å
  • b = 11.9955 (6) Å
  • c = 13.8643 (7) Å
  • β = 92.156 (4)°
  • V = 1110.18 (9) Å3
  • Z = 2
  • Mo Kα radiation
  • μ = 0.89 mm−1
  • T = 295 (2) K
  • 0.6 × 0.1 × 0.1 mm

Data collection

  • Oxford Diffraction Ruby CCD diffractometer
  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006 [triangle]) T min = 0.532, T max = 0.915
  • 6336 measured reflections
  • 1960 independent reflections
  • 1288 reflections with I > 2σ(I)
  • R int = 0.050

Refinement

  • R[F 2 > 2σ(F 2)] = 0.044
  • wR(F 2) = 0.106
  • S = 0.90
  • 1960 reflections
  • 155 parameters
  • H-atom parameters constrained
  • Δρmax = 0.36 e Å−3
  • Δρmin = −0.39 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 [triangle]); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 [triangle]); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEPII (Johnson, 1976 [triangle]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003 [triangle]).

Table 1
Selected bond lengths (Å)
Table 2
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S160053680803328X/hy2159sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S160053680803328X/hy2159Isup2.hkl

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

Acknowledgments

The Polish Ministry of Science and Higher Education under grants BW/8000-5-0462-8 and DS/8210-40-086-8 financially supported this work.

supplementary crystallographic information

Comment

In the past few decades, the interest in the coordination chemistry and biochemistry of vanadium compounds has increased due to their influence on biological systems, viz. in diabetes mellitus (Sakurai, 2002) and cancer treatment (Evangelou, 2002). Moreover, vanadium activity has been discovered in the inhibitory and promotory processes like nitrogenases (Eady, 2003), haloperoxidases (Butler & Walker, 1993; Carter-Franklin et al., 2003; Rehder et al., 2003), mutases and isomerases (Mendz, 1991).

The structure of the title compound was first reported in orthorhombic space group Pbca (Mokry & Carrano, 1993). Here we report the synthesis and structure of a new polymorph of the compound in space group P21/c. We have described earlier the spectroscopic properties (IR, UV-Vis, 1H and 51V NMR) of this compound (Kwiatkowski et al., 2003). The half of the molecule, constituting the asymmetric unit of the structure, is related to the other half by a center of symmetry. Each VV atom is six-coordinated by two strongly (O15, O16) and one weakly (O15i) associated oxide groups and by the tridentate Schiff base ligand, viz. a phenolate O atom (O7), a secondary amine N atom (N12), both occupying the axial positions, and an imine N atom (N9) (Fig. 1). The geometry about the V atom is distorted octahedral. The V14 ═O16 bond length of 1.612 (2) Å (Table 1) compares well with the distances between V and the doubly bonded O atoms (Romanowski et al., 2008; Root et al., 1993). The V14, O15, V14i, O15i atoms are situated at vertices of a parallelogram with the acute O15—V14—O15i angle of 78.64 (8)° [symmetry code: (i) -x, -y+2, -z]. The five-membered ring comprising the ethylenediamine moiety exhibits twofold disorder. The C10 and C11 atoms are disordered over two sites, with occupancy factors of 0.776 (14) and 0.224 (14) for C10A/C11A and C10B/C11B, respectively. The five-membered chelate ring defined by V14, N9, C10A, C11A, N12 adopts an envelope conformation on C10A, with P = 244.0 (3)° and τ(M) = 54.9 (4)° for reference bond V14—N9 (Rao et al., 1981) and the ring formed by V14, N9, C10B, C11B, N12 takes the envelope conformation on C11B, with P = 81.8 (7)° and τ(M) = 62.3 (9)° for reference bond V14—N9 (Fig. 1).

In the crystal structure, the dimers are linked through C—H···O hydrogen bonds (Table 1), forming columns along the a-axis. There are C—H···π interactions (Fig. 2), involving minor disordered C11B atom [C11B···Cg1iii = 3.47 (2), H11C···Cg1iii = 2.82 Å; Cg1 = centroid of the ring C1–C6; symmetry code: (iii) x, 3/2-y, -1/2+z].

Experimental

The title compound was obtained in a template/complexation reaction, which was described earlier (Kwiatkowski et al., 2003). A solution of N-methylethylenediamine (1 mmol) in absolute EtOH (10 ml) was added under stirring to a freshly filtered solution of vanadium(V) oxytriethoxide (1 mmol) in absolute EtOH (50 ml), producing a yellow suspension of the intermediate. Salicylaldehyde (1 mmol) dissolved in absolute EtOH was added to the aforementioned suspension. After refluxing (70 ml) of the resulting mixture for 2 h and its cooling to room temperature, the separated solids were filtered off, washed several times with EtOH, recrystallized from DMSO-EtOH mixture and dried over molecular sieves.

Refinement

All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 (CH), 0.97 (CH2) and 0.96 (CH3)Å and N—H = 0.91 Å, and with Uiso(H) = 1.2 (or 1.5 for methyl)Ueq(C,N). The occupancy ratio was determined by isotropic refinement for the disordered site and was refined freely. The minor disordered sites were refined isotropically.

Figures

Fig. 1.
The molecular structure of the title compound, with displacement ellipsoids drawn at the 25% probability level. [Symmetry code: (i) -x, -y+2, -z.]
Fig. 2.
The arrangement of the molecules viewed approximately along the a-axis. The C—H···O hydrogen bonds are represented by dashed lines and the C—H···π interactions are represented by ...

Crystal data

[V2(C10H13N2O)2O4]F000 = 536
Mr = 520.33Dx = 1.557 Mg m3
Monoclinic, P21/cMo Kα radiation λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1960 reflections
a = 6.6801 (2) Åθ = 3.1–25.1º
b = 11.9955 (6) ŵ = 0.89 mm1
c = 13.8643 (7) ÅT = 295 (2) K
β = 92.156 (4)ºNeedle, yellow
V = 1110.18 (9) Å30.6 × 0.1 × 0.1 mm
Z = 2

Data collection

Oxford Diffraction Ruby CCD diffractometer1960 independent reflections
Radiation source: Enhance (Mo) X-ray Source1288 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.050
Detector resolution: 10.4002 pixels mm-1θmax = 25.1º
T = 295(2) Kθmin = 3.1º
ω scansh = −7→7
Absorption correction: multi-scan(CrysAlis RED; Oxford Diffraction, 2006)k = −13→14
Tmin = 0.532, Tmax = 0.915l = −13→16
6336 measured reflections

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.106  w = 1/[σ2(Fo2) + (0.064P)2] where P = (Fo2 + 2Fc2)/3
S = 0.90(Δ/σ)max < 0.001
1960 reflectionsΔρmax = 0.36 e Å3
155 parametersΔρmin = −0.39 e Å3
Primary atom site location: structure-invariant direct methodsExtinction correction: none

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

xyzUiso*/UeqOcc. (<1)
C10.2360 (4)0.9625 (3)0.2273 (2)0.0439 (8)
C20.4291 (4)0.9220 (3)0.2071 (2)0.0463 (9)
C30.5887 (5)0.9466 (4)0.2713 (3)0.0609 (10)
H3A0.71560.91990.25830.073*
C40.5646 (6)1.0085 (4)0.3528 (3)0.0739 (12)
H4A0.67351.02390.39450.089*
C50.3749 (6)1.0482 (4)0.3724 (3)0.0696 (11)
H5A0.35621.09000.42780.084*
C60.2169 (5)1.0261 (3)0.3110 (2)0.0553 (9)
H6A0.09161.05420.32500.066*
O70.0760 (3)0.9451 (2)0.16978 (15)0.0495 (6)
C80.4690 (5)0.8585 (3)0.1220 (3)0.0505 (9)
H8A0.59810.83090.11630.061*
N90.3417 (4)0.8368 (3)0.0538 (2)0.0514 (8)
C10A0.3951 (9)0.7645 (7)−0.0286 (4)0.0583 (19)0.776 (14)
H10A0.53930.7566−0.03120.070*0.776 (14)
H10B0.33610.6911−0.02260.070*0.776 (14)
C10B0.442 (3)0.820 (2)−0.0377 (13)0.042 (6)*0.224 (14)
H10C0.56160.7741−0.02930.050*0.224 (14)
H10D0.47550.8895−0.06830.050*0.224 (14)
C11A0.3133 (8)0.8217 (7)−0.1157 (4)0.058 (2)0.776 (14)
H11A0.33360.7765−0.17260.070*0.776 (14)
H11B0.37970.8928−0.12390.070*0.776 (14)
C11B0.272 (2)0.758 (2)−0.0932 (14)0.044 (6)*0.224 (14)
H11C0.31480.7358−0.15660.053*0.224 (14)
H11D0.23470.6911−0.05840.053*0.224 (14)
N120.0951 (4)0.8389 (3)−0.1021 (2)0.0504 (7)
H12A0.06740.9027−0.13550.060*
C13−0.0425 (6)0.7569 (4)−0.1475 (3)0.0758 (12)
H13A−0.00930.7463−0.21360.114*
H13B−0.17770.7836−0.14480.114*
H13C−0.03050.6872−0.11370.114*
V140.02849 (7)0.88119 (5)0.04358 (4)0.0417 (2)
O15−0.1739 (3)0.95553 (19)0.00898 (15)0.0437 (6)
O16−0.0525 (3)0.7584 (2)0.06852 (19)0.0629 (7)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0506 (18)0.043 (2)0.0391 (19)0.0011 (16)0.0086 (15)0.0132 (17)
C20.0465 (18)0.046 (2)0.047 (2)0.0026 (16)0.0079 (16)0.0110 (17)
C30.0506 (19)0.066 (3)0.066 (3)0.0006 (19)−0.0012 (18)0.007 (2)
C40.061 (2)0.087 (3)0.073 (3)−0.002 (2)−0.015 (2)−0.003 (3)
C50.084 (3)0.069 (3)0.055 (2)−0.004 (2)−0.003 (2)−0.008 (2)
C60.063 (2)0.052 (2)0.051 (2)0.0049 (19)0.0067 (17)0.005 (2)
O70.0427 (11)0.0664 (17)0.0397 (13)0.0116 (12)0.0066 (10)0.0001 (12)
C80.0410 (17)0.056 (2)0.056 (2)0.0101 (16)0.0118 (17)0.0117 (19)
N90.0452 (14)0.065 (2)0.0452 (17)0.0181 (14)0.0153 (14)0.0048 (16)
C10A0.050 (3)0.055 (4)0.071 (4)0.015 (3)0.024 (3)−0.004 (3)
C11A0.068 (3)0.058 (5)0.050 (3)0.014 (3)0.027 (2)−0.001 (3)
N120.0481 (14)0.0490 (18)0.0544 (18)0.0095 (14)0.0058 (13)−0.0125 (15)
C130.094 (3)0.063 (3)0.070 (3)−0.013 (2)−0.005 (2)−0.016 (2)
V140.0397 (3)0.0394 (4)0.0468 (4)0.0031 (3)0.0116 (2)0.0003 (3)
O150.0386 (11)0.0426 (14)0.0505 (13)0.0024 (10)0.0085 (9)−0.0031 (11)
O160.0645 (14)0.0455 (15)0.0805 (19)0.0012 (12)0.0262 (13)0.0087 (14)

Geometric parameters (Å, °)

C1—O71.326 (4)C10B—C11B1.54 (3)
C1—C61.398 (5)C10B—H10C0.9700
C1—C21.417 (4)C10B—H10D0.9700
C2—C31.395 (5)C11A—N121.491 (5)
C2—C81.437 (5)C11A—H11A0.9700
C3—C41.367 (5)C11A—H11B0.9700
C3—H3A0.9300C11B—N121.535 (17)
C4—C51.390 (5)C11B—H11C0.9700
C4—H4A0.9300C11B—H11D0.9700
C5—C61.357 (5)N12—C131.471 (4)
C5—H5A0.9300N12—V142.146 (3)
C6—H6A0.9300N12—H12A0.9100
O7—V141.926 (2)C13—H13A0.9600
C8—N91.275 (4)C13—H13B0.9600
C8—H8A0.9300C13—H13C0.9600
N9—C10B1.472 (18)V14—O161.612 (2)
N9—C10A1.489 (6)V14—O151.674 (2)
N9—V142.158 (3)V14—O15i2.316 (2)
C10A—C11A1.476 (9)V14—V14i3.1136 (11)
C10A—H10A0.9700O15—V14i2.316 (2)
C10A—H10B0.9700
O7—C1—C6119.2 (3)H11A—C11A—H11B108.5
O7—C1—C2123.1 (3)N12—C11B—C10B106.6 (16)
C6—C1—C2117.6 (3)N12—C11B—H11C110.4
C3—C2—C1118.8 (3)C10B—C11B—H11C110.4
C3—C2—C8118.4 (3)N12—C11B—H11D110.4
C1—C2—C8122.8 (3)C10B—C11B—H11D110.4
C4—C3—C2122.1 (3)H11C—C11B—H11D108.6
C4—C3—H3A118.9C13—N12—C11A116.9 (4)
C2—C3—H3A118.9C13—N12—C11B94.5 (8)
C3—C4—C5118.9 (4)C13—N12—V14114.3 (2)
C3—C4—H4A120.5C11A—N12—V14112.9 (2)
C5—C4—H4A120.5C11B—N12—V14105.1 (7)
C6—C5—C4120.3 (4)C13—N12—H12A103.5
C6—C5—H5A119.9C11A—N12—H12A103.5
C4—C5—H5A119.9C11B—N12—H12A135.8
C5—C6—C1122.3 (3)V14—N12—H12A103.5
C5—C6—H6A118.9N12—C13—H13A109.5
C1—C6—H6A118.9N12—C13—H13B109.5
C1—O7—V14135.30 (19)H13A—C13—H13B109.5
N9—C8—C2125.3 (3)N12—C13—H13C109.5
N9—C8—H8A117.4H13A—C13—H13C109.5
C2—C8—H8A117.4H13B—C13—H13C109.5
C8—N9—C10B110.8 (7)O16—V14—O15105.93 (11)
C8—N9—C10A121.1 (3)O16—V14—O7102.36 (12)
C8—N9—V14128.1 (2)O15—V14—O798.73 (9)
C10B—N9—V14116.8 (7)O16—V14—N1293.95 (13)
C10A—N9—V14110.7 (3)O15—V14—N1292.87 (10)
C11A—C10A—N9105.4 (5)O7—V14—N12156.46 (10)
C11A—C10A—H10A110.7O16—V14—N995.31 (12)
N9—C10A—H10A110.7O15—V14—N9156.99 (11)
C11A—C10A—H10B110.7O7—V14—N984.96 (10)
N9—C10A—H10B110.7N12—V14—N976.64 (10)
H10A—C10A—H10B108.8O16—V14—O15i171.43 (10)
N9—C10B—C11B98.5 (15)O15—V14—O15i78.64 (8)
N9—C10B—H10C112.1O7—V14—O15i83.83 (9)
C11B—C10B—H10C112.1N12—V14—O15i78.44 (10)
N9—C10B—H10D112.1N9—V14—O15i79.20 (9)
C11B—C10B—H10D112.1O16—V14—V14i152.02 (10)
H10C—C10B—H10D109.7O15—V14—V14i46.82 (7)
C10A—C11A—N12107.1 (5)O7—V14—V14i90.10 (8)
C10A—C11A—H11A110.3N12—V14—V14i82.99 (9)
N12—C11A—H11A110.3N9—V14—V14i110.83 (8)
C10A—C11A—H11B110.3O15i—V14—V14i31.82 (5)
N12—C11A—H11B110.3V14—O15—V14i101.36 (8)
O7—C1—C2—C3178.8 (3)C11B—N12—V14—O16−68.6 (10)
C6—C1—C2—C30.5 (5)C13—N12—V14—O15−72.6 (3)
O7—C1—C2—C80.1 (5)C11A—N12—V14—O15150.5 (4)
C6—C1—C2—C8−178.2 (3)C11B—N12—V14—O15−174.8 (10)
C1—C2—C3—C4−0.2 (6)C13—N12—V14—O7167.7 (3)
C8—C2—C3—C4178.6 (4)C11A—N12—V14—O730.8 (5)
C2—C3—C4—C50.1 (7)C11B—N12—V14—O765.5 (10)
C3—C4—C5—C6−0.5 (6)C13—N12—V14—N9128.1 (3)
C4—C5—C6—C10.8 (6)C11A—N12—V14—N9−8.8 (4)
O7—C1—C6—C5−179.2 (3)C11B—N12—V14—N926.0 (10)
C2—C1—C6—C5−0.8 (5)C13—N12—V14—O15i−150.4 (3)
C6—C1—O7—V14171.4 (2)C11A—N12—V14—O15i72.7 (4)
C2—C1—O7—V14−6.9 (5)C11B—N12—V14—O15i107.4 (10)
C3—C2—C8—N9−174.6 (4)C13—N12—V14—V14i−118.5 (2)
C1—C2—C8—N94.1 (6)C11A—N12—V14—V14i104.6 (4)
C2—C8—N9—C10B153.2 (11)C11B—N12—V14—V14i139.4 (10)
C2—C8—N9—C10A−176.4 (5)C8—N9—V14—O16−104.1 (3)
C2—C8—N9—V14−2.2 (5)C10B—N9—V14—O16101.9 (12)
C8—N9—C10A—C11A−135.7 (5)C10A—N9—V14—O1670.7 (4)
C10B—N9—C10A—C11A−59.1 (15)C8—N9—V14—O1598.4 (4)
V14—N9—C10A—C11A49.1 (7)C10B—N9—V14—O15−55.7 (12)
C8—N9—C10B—C11B161.4 (12)C10A—N9—V14—O15−86.8 (5)
C10A—N9—C10B—C11B44.5 (16)C8—N9—V14—O7−2.1 (3)
V14—N9—C10B—C11B−40 (2)C10B—N9—V14—O7−156.2 (12)
N9—C10A—C11A—N12−55.7 (8)C10A—N9—V14—O7172.7 (4)
N9—C10B—C11B—N1263 (2)C8—N9—V14—N12163.1 (3)
C10A—C11A—N12—C13−97.6 (6)C10B—N9—V14—N129.0 (11)
C10A—C11A—N12—C11B−44.7 (12)C10A—N9—V14—N12−22.1 (4)
C10A—C11A—N12—V1438.2 (8)C8—N9—V14—O15i82.6 (3)
C10B—C11B—N12—C13−175.1 (16)C10B—N9—V14—O15i−71.5 (11)
C10B—C11B—N12—C11A50.5 (15)C10A—N9—V14—O15i−102.7 (4)
C10B—C11B—N12—V14−58.4 (19)C8—N9—V14—V14i86.1 (3)
C1—O7—V14—O16101.1 (3)C10B—N9—V14—V14i−68.0 (12)
C1—O7—V14—O15−150.4 (3)C10A—N9—V14—V14i−99.1 (4)
C1—O7—V14—N12−31.7 (5)O16—V14—O15—V14i−172.54 (11)
C1—O7—V14—N96.8 (3)O7—V14—O15—V14i81.85 (10)
C1—O7—V14—O15i−72.9 (3)N12—V14—O15—V14i−77.60 (10)
C1—O7—V14—V14i−104.1 (3)N9—V14—O15—V14i−15.9 (3)
C13—N12—V14—O1633.6 (3)O15i—V14—O15—V14i0.0
C11A—N12—V14—O16−103.3 (4)

Symmetry codes: (i) −x, −y+2, −z.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C8—H8A···O16ii0.932.603.520 (4)170
C11B—H11C···Cg1iiiiii0.972.823.47 (2)124

Symmetry codes: (ii) x+1, y, z; (iii) x, −y+3/2, z−1/2.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HY2159).

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