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Acta Cryst. (2008). E64, m1548-m1549    [ doi:10.1107/S160053680803328X ]

A monoclinic polymorph of di-[mu]-oxido-bis({2-[2-(methylamino)ethyliminomethyl]phenolato-[kappa]3N,N',O}oxidovanadium(V))

G. Romanowski, M. Wera and A. Sikorski

Abstract top

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). 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...[pi] interactions between the dimers.

Comment top

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].

Related literature top

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

Experimental top

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 top

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.

Computing details top

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

Figures top
[Figure 1] 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.]
[Figure 2] 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 dotted lines. [Symmetry codes: (ii) 1+x, y, z; (iii) x, 3/2-y, -1/2+z.]
di-µ-oxido-bis({2-[2-(methylamino)ethyliminomethyl]phenolato- κ3N,N',O}oxidovanadium(V)) top
Crystal data top
[V2(C10H13N2O)2O4]F(000) = 536
Mr = 520.33Dx = 1.557 Mg m−3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 1960 reflections
a = 6.6801 (2) Åθ = 3.1–25.1°
b = 11.9955 (6) ŵ = 0.89 mm−1
c = 13.8643 (7) ÅT = 295 K
β = 92.156 (4)°Needle, yellow
V = 1110.18 (9) Å30.6 × 0.1 × 0.1 mm
Z = 2
Data collection top
Oxford Diffraction Ruby CCD
diffractometer		1960 independent reflections
Radiation source: Enhance (Mo) X-ray Source1288 reflections with I > 2σ(I)
graphiteRint = 0.050
Detector resolution: 10.4002 pixels mm-1θmax = 25.1°, θmin = 3.1°
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 top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.106H-atom parameters constrained
S = 0.90 w = 1/[σ2(Fo2) + (0.064P)2]
where P = (Fo2 + 2Fc2)/3
1960 reflections(Δ/σ)max < 0.001
155 parametersΔρmax = 0.36 e Å−3
0 restraintsΔρmin = −0.39 e Å−3
Crystal data top
[V2(C10H13N2O)2O4]V = 1110.18 (9) Å3
Mr = 520.33Z = 2
Monoclinic, P21/cMo Kα radiation
a = 6.6801 (2) ŵ = 0.89 mm−1
b = 11.9955 (6) ÅT = 295 K
c = 13.8643 (7) Å0.6 × 0.1 × 0.1 mm
β = 92.156 (4)°
Data collection top
Oxford Diffraction Ruby CCD
diffractometer		1960 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2006)		1288 reflections with I > 2σ(I)
Tmin = 0.532, Tmax = 0.915Rint = 0.050
6336 measured reflectionsθmax = 25.1°
Refinement top
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.106Δρmax = 0.36 e Å−3
S = 0.90Δρmin = −0.39 e Å−3
1960 reflectionsAbsolute structure: ?
155 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
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) top
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, °) top
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, °) top
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.
Table 1
Selected geometric parameters (Å) top
O7—V141.926 (2)V14—O161.612 (2)
N9—V142.158 (3)V14—O151.674 (2)
N12—V142.146 (3)V14—O15i2.316 (2)
Symmetry codes: (i) −x, −y+2, −z.
Table 2
Hydrogen-bond geometry (Å, °) top
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.
Acknowledgements top

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.

references
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