A binuclear vanadium oxyfluoride: di-μ-oxido-bis­[(2,2′-bipyrid­yl)fluorido­oxidovanadium(V)]

The title compound, [V₂F₂O₄(C₁₀H₈N)₂], is a centrosymmetric binuclear vanadium(V) species with the metal ions in a distorted octa­hedral environment. The coordination geometries of the symmetry-equivalent V^V atoms are defined by cis-terminal fluoride and oxide groups, unsymmetrically bridging oxide groups and the N-atom donors of the bipyridyl ligand. The crystal packing is stabilized by weak inter­molecular C—H...O and C—H...F hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 90 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.031
• wR factor = 0.079
• Data-to-parameter ratio = 16.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT480_ALERT_4_C Long H...A H-Bond Reported H1     ..  F1      ..       2.59 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H3     ..  F1      ..       2.86 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H4     ..  F1      ..       2.60 Ang.
PLAT481_ALERT_4_C Long D...A H-Bond Reported C3     ..  F1      ..       3.76 Ang.
PLAT912_ALERT_4_C Missing # of FCF Reflections Above STh/L=  0.600          3

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   5 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

---

S1. Comment

Metal oxyfluorides have attracted considerable contemporary interest as a consequence of their compositional range and structural versatility and for properties such as magnetism, catalysis and non-linear optical behavior (Adil, et al. (2010); Burkholder & Zubieta (2004); DeBurgomaster & Zubieta (2010); Jones, et al. (2010); Michailovski, et al. (2006 and 2009). One approach to the preparation of novel metal oxyfluorides is the exploitation of hydrothermal chemistry where the complexity of the synthetic domain allows incorporation of fluoride into metal oxide frameworks, providing unusual and often unprecedented structures. Furthermore, the metal-oxyfluoride core can be stabilized or modified by the introduction of appropriate coligands, such as organonitrogen donors of the pyridyl family. In the course of our investigations of the hydrothermal chemistry of metal oxides in the presence of fluoride anion, the title compound [V₂F₂O₄(2,2'-bpy)₂] was isolated.

The compound crystallizes in the monoclinic space group C2/c with four binuclear molecules per unit cell. The two halves of the binuclear unit are related by a center of symmetry at the mid-point of the V···V vector. The coordination geometry is distorted octahedral with {VFO₃N} coordination (Fig. 1). The µ-bis-oxo bridging mode produces a V₂O₂ rhombus with alternating short-long V—O bond distances of 1.705 (1) Å and 2.293 (1) Å, respectively. The terminal oxo-groups rest in the plane of the V₂O₂ rhombus and exhibit a pronounced trans-influence on the elongated bridging oxo-group-vanadium distance, V1—O2. The coordination geometry at the vanadium sites also exhibits a fluoride ligand with V—F of 1.806 (1) Å with the V—F vector approximately normal to the V₂O₂ rhombus. The V—F vectors of the binuclear unit adopt an anti-orientation with respect to the V₂O₂ rhombus. The geometry is completed by the nitrogen donors of the 2,2'-bipyridine ligand, which occupy positions trans to the short V—O bond of the rhombus and trans to the terminal fluoride ligand. The crystal packing is stabilized by weak intermolecular C—H···O and C—H···F hydrogen bonding.

Related literature

For oxyfluoromolybdates and oxyfluorovanadates, see: Adil et al. (2010); Burkholder & Zubieta (2004); DeBurgomaster & Zubieta (2010); Jones et al. (2010); Michailovski et al. (2006, 2009).

S2. Experimental

A mixture of V₂O₅ (0.062 g, 0.34 mmol), 2,2'-bipyridine (0.320 g, 2.05 mmol), H₂O (5 ml, 277.5 mmol) and HF (0.200 ml, 5.80 mmol) in the mole ratio 1.00:6.03:1620:17.06 was stirred briefly before heating to 170 °C for 48 h (initial and final pH values of 2.5 and 2.0, respectively). Yellow rods suitable for X-ray diffraction were isolated in 65% yield. Anal. Calcd. for C₂₀H₁₆F₂N₄O₄V₂: C, 46.5; H, 3.10; N, 10.8. Found: C, 46.3; H, 3.01; N, 11.0.

S3. Refinement

All hydrogen atoms were discernable in the difference Fourier map. The hydrogen atoms were placed in calculated positions with C—H = 0.95 Å and included in the riding model approximation with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: CrystalMaker (Palmer, 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures

Fig. 1. View of the molecular dimer of the title compound, with the atom-labeling scheme and the displacement ellipsoids drawn at the 50% probability level. Color scheme: vanadium, orange; oxygen, red; fluorine, green; nitrogen, light blue; carbon, black; hydrogen, pink.

di-µ-oxido-bis[(2,2'-bipyridyl)fluoridooxidovanadium(V)]

Crystal data

[V2F2O4(C10H8N)2]	F(000) = 1040.0
Mr = 516.25	Dx = 1.737 Mg m^−3 Dm = 1.74 (2) Mg m^−3 Dm measured by flotation
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5752 reflections
a = 9.7526 (6) Å	θ = 2.6–28.3°
b = 12.6499 (8) Å	µ = 1.00 mm^−1
c = 16.023 (5) Å	T = 90 K
β = 92.631 (5)°	Rod, yellow
V = 1974.7 (6) Å^3	0.22 × 0.12 × 0.10 mm
Z = 4

Data collection

Bruker APEX CCD area-detector diffractometer	2406 independent reflections
Radiation source: fine-focus sealed tube	2357 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.018
Detector resolution: 512 pixels mm^-1	θmax = 28.1°, θmin = 2.5°
φ and ω scans	h = −12→12
Absorption correction: multi-scan (SADABS; Bruker, 1998)	k = −16→16
Tmin = 0.866, Tmax = 0.905	l = −20→21
9692 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.031	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.079	H-atom parameters constrained
S = 1.13	w = 1/[σ^2(Fo^2) + (0.0314P)^2 + 4.0741P] where P = (Fo^2 + 2Fc^2)/3
2406 reflections	(Δ/σ)max = 0.001
145 parameters	Δρmax = 0.38 e Å^−3
0 restraints	Δρmin = −0.38 e Å^−3

Special details

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.

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

	x	y	z	Uiso*/Ueq
V1	0.10805 (3)	1.04160 (2)	0.066763 (17)	0.01424 (10)
F1	−0.01010 (11)	1.03518 (8)	0.15020 (6)	0.0199 (2)
O1	0.21267 (13)	1.13285 (10)	0.10042 (8)	0.0205 (3)
O2	−0.01453 (12)	0.90041 (9)	0.01329 (7)	0.0133 (2)
N1	0.20945 (14)	0.90735 (11)	0.13175 (9)	0.0144 (3)
N2	0.25791 (14)	0.97955 (11)	−0.01525 (9)	0.0142 (3)
C1	0.17578 (18)	0.87555 (14)	0.20780 (11)	0.0176 (3)
H1	0.1106	0.9156	0.2367	0.021*
C2	0.23257 (18)	0.78627 (14)	0.24593 (11)	0.0183 (3)
H2	0.2056	0.7650	0.2996	0.022*
C3	0.32950 (18)	0.72849 (13)	0.20438 (11)	0.0185 (3)
H3	0.3696	0.6669	0.2290	0.022*
C4	0.36682 (18)	0.76235 (14)	0.12620 (11)	0.0180 (3)
H4	0.4339	0.7248	0.0969	0.022*
C5	0.30457 (16)	0.85198 (13)	0.09144 (10)	0.0137 (3)
C6	0.33609 (17)	0.89567 (13)	0.00892 (10)	0.0144 (3)
C7	0.44046 (17)	0.85774 (14)	−0.03932 (11)	0.0183 (3)
H7	0.4940	0.7985	−0.0214	0.022*
C8	0.46484 (17)	0.90815 (15)	−0.11414 (11)	0.0199 (4)
H8	0.5357	0.8839	−0.1481	0.024*
C9	0.38475 (18)	0.99419 (15)	−0.13875 (11)	0.0204 (4)
H9	0.4002	1.0299	−0.1896	0.024*
C10	0.28181 (18)	1.02718 (14)	−0.08794 (11)	0.0178 (3)
H10	0.2262	1.0856	−0.1052	0.021*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
V1	0.01400 (15)	0.01331 (15)	0.01525 (16)	0.00446 (10)	−0.00118 (10)	−0.00316 (10)
F1	0.0225 (5)	0.0227 (5)	0.0148 (5)	0.0086 (4)	0.0030 (4)	−0.0001 (4)
O1	0.0197 (6)	0.0188 (6)	0.0226 (6)	0.0028 (5)	−0.0028 (5)	−0.0063 (5)
O2	0.0146 (5)	0.0124 (5)	0.0129 (5)	0.0035 (4)	0.0002 (4)	−0.0001 (4)
N1	0.0134 (6)	0.0154 (6)	0.0140 (6)	0.0032 (5)	−0.0016 (5)	−0.0015 (5)
N2	0.0132 (6)	0.0160 (6)	0.0134 (7)	0.0011 (5)	−0.0001 (5)	−0.0018 (5)
C1	0.0180 (8)	0.0197 (8)	0.0150 (8)	0.0044 (6)	0.0000 (6)	−0.0017 (6)
C2	0.0207 (8)	0.0193 (8)	0.0145 (8)	0.0009 (6)	−0.0010 (6)	0.0004 (6)
C3	0.0218 (8)	0.0130 (7)	0.0201 (8)	0.0030 (6)	−0.0037 (7)	0.0003 (6)
C4	0.0183 (8)	0.0151 (8)	0.0207 (8)	0.0049 (6)	0.0006 (6)	−0.0015 (6)
C5	0.0128 (7)	0.0140 (7)	0.0139 (7)	0.0009 (6)	−0.0022 (6)	−0.0028 (6)
C6	0.0140 (7)	0.0140 (7)	0.0150 (8)	0.0002 (6)	−0.0014 (6)	−0.0033 (6)
C7	0.0152 (8)	0.0188 (8)	0.0208 (8)	0.0032 (6)	0.0011 (6)	−0.0033 (6)
C8	0.0151 (8)	0.0257 (9)	0.0192 (8)	0.0012 (7)	0.0040 (6)	−0.0050 (7)
C9	0.0182 (8)	0.0258 (9)	0.0173 (8)	−0.0005 (7)	0.0031 (6)	0.0015 (7)
C10	0.0161 (8)	0.0194 (8)	0.0178 (8)	0.0023 (6)	0.0001 (6)	0.0009 (6)

Geometric parameters (Å, º)

V1—O1	1.6167 (13)	C2—H2	0.9500
V1—O2^i	1.7052 (12)	C3—C4	1.388 (3)
V1—F1	1.8064 (11)	C3—H3	0.9500
V1—N2	2.1576 (14)	C4—C5	1.390 (2)
V1—N1	2.2027 (14)	C4—H4	0.9500
V1—O2	2.2934 (12)	C5—C6	1.478 (2)
V1—V1^i	3.1165 (6)	C6—C7	1.391 (2)
N1—C1	1.338 (2)	C7—C8	1.388 (3)
N1—C5	1.350 (2)	C7—H7	0.9500
N2—C10	1.341 (2)	C8—C9	1.386 (3)
N2—C6	1.353 (2)	C8—H8	0.9500
C1—C2	1.387 (2)	C9—C10	1.386 (2)
C1—H1	0.9500	C9—H9	0.9500
C2—C3	1.389 (2)	C10—H10	0.9500
O1—V1—O2^i	104.55 (6)	N1—C1—H1	118.8
O1—V1—F1	101.51 (6)	C2—C1—H1	118.8
O2^i—V1—F1	103.81 (5)	C1—C2—C3	118.95 (16)
O1—V1—N2	91.61 (6)	C1—C2—H2	120.5
O2^i—V1—N2	93.00 (5)	C3—C2—H2	120.5
F1—V1—N2	155.14 (5)	C4—C3—C2	118.86 (16)
O1—V1—N1	97.47 (6)	C4—C3—H3	120.6
O2^i—V1—N1	154.20 (5)	C2—C3—H3	120.6
F1—V1—N1	84.45 (5)	C3—C4—C5	119.03 (16)
N2—V1—N1	72.87 (5)	C3—C4—H4	120.5
O1—V1—O2	172.25 (6)	C5—C4—H4	120.5
O2^i—V1—O2	78.60 (5)	N1—C5—C4	121.90 (16)
F1—V1—O2	84.39 (5)	N1—C5—C6	114.17 (14)
N2—V1—O2	81.09 (5)	C4—C5—C6	123.93 (15)
N1—V1—O2	77.95 (5)	N2—C6—C7	121.90 (16)
O1—V1—V1^i	150.07 (5)	N2—C6—C5	114.31 (14)
O2^i—V1—V1^i	46.17 (4)	C7—C6—C5	123.74 (15)
F1—V1—V1^i	93.36 (4)	C8—C7—C6	118.69 (16)
N2—V1—V1^i	85.11 (4)	C8—C7—H7	120.7
N1—V1—V1^i	109.81 (4)	C6—C7—H7	120.7
O2—V1—V1^i	32.44 (3)	C9—C8—C7	119.33 (16)
V1^i—O2—V1	101.40 (5)	C9—C8—H8	120.3
C1—N1—C5	118.83 (15)	C7—C8—H8	120.3
C1—N1—V1	122.59 (11)	C10—C9—C8	118.90 (17)
C5—N1—V1	118.50 (11)	C10—C9—H9	120.5
C10—N2—C6	118.87 (15)	C8—C9—H9	120.5
C10—N2—V1	121.00 (11)	N2—C10—C9	122.31 (16)
C6—N2—V1	119.98 (11)	N2—C10—H10	118.8
N1—C1—C2	122.42 (16)	C9—C10—H10	118.8
O2^i—V1—O2—V1^i	0.0	V1^i—V1—N2—C6	−112.39 (12)
F1—V1—O2—V1^i	105.34 (6)	C5—N1—C1—C2	−1.6 (3)
N2—V1—O2—V1^i	−94.91 (6)	V1—N1—C1—C2	175.09 (13)
N1—V1—O2—V1^i	−169.16 (6)	N1—C1—C2—C3	1.0 (3)
O1—V1—N1—C1	91.27 (14)	C1—C2—C3—C4	0.3 (3)
O2^i—V1—N1—C1	−120.14 (16)	C2—C3—C4—C5	−1.0 (3)
F1—V1—N1—C1	−9.65 (13)	C1—N1—C5—C4	0.9 (2)
N2—V1—N1—C1	−179.35 (14)	V1—N1—C5—C4	−175.93 (12)
O2—V1—N1—C1	−95.08 (13)	C1—N1—C5—C6	−178.60 (14)
V1^i—V1—N1—C1	−101.23 (13)	V1—N1—C5—C6	4.58 (18)
O1—V1—N1—C5	−92.04 (13)	C3—C4—C5—N1	0.4 (3)
O2^i—V1—N1—C5	56.55 (19)	C3—C4—C5—C6	179.83 (15)
F1—V1—N1—C5	167.04 (12)	C10—N2—C6—C7	0.1 (2)
N2—V1—N1—C5	−2.66 (11)	V1—N2—C6—C7	−175.39 (12)
O2—V1—N1—C5	81.61 (12)	C10—N2—C6—C5	177.71 (14)
V1^i—V1—N1—C5	75.46 (12)	V1—N2—C6—C5	2.18 (18)
O1—V1—N2—C10	−78.03 (14)	N1—C5—C6—N2	−4.3 (2)
O2^i—V1—N2—C10	26.64 (13)	C4—C5—C6—N2	176.19 (15)
F1—V1—N2—C10	159.61 (13)	N1—C5—C6—C7	173.19 (15)
N1—V1—N2—C10	−175.34 (14)	C4—C5—C6—C7	−6.3 (3)
O2—V1—N2—C10	104.61 (13)	N2—C6—C7—C8	0.3 (3)
V1^i—V1—N2—C10	72.17 (13)	C5—C6—C7—C8	−177.03 (15)
O1—V1—N2—C6	97.41 (13)	C6—C7—C8—C9	−0.2 (3)
O2^i—V1—N2—C6	−157.93 (12)	C7—C8—C9—C10	−0.3 (3)
F1—V1—N2—C6	−25.0 (2)	C6—N2—C10—C9	−0.7 (3)
N1—V1—N2—C6	0.09 (12)	V1—N2—C10—C9	174.79 (13)
O2—V1—N2—C6	−79.96 (12)	C8—C9—C10—N2	0.8 (3)

Symmetry code: (i) −x, −y+2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1···F1^ii	0.95	2.59	3.493 (2)	160
C2—H2···O1^iii	0.95	2.42	3.161 (2)	134
C3—H3···F1^iv	0.95	2.43	3.050 (2)	123
C3—H3···F1^iii	0.95	2.86	3.760 (2)	159
C4—H4···O2^v	0.95	2.52	3.407 (2)	155
C4—H4···F1^iv	0.95	2.60	3.131 (2)	116
C7—H7···O2^v	0.95	2.53	3.366 (2)	147

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