A new hybrid organic-inorganic chain: [(phen)Cu-[mu]-([kappa]²O:O'-VP₂O₁₀H₃)₂-Cu(phen)]_n

The structure of the title compound, poly[(dihydrogen­phosphato-[kappa]O)([mu]₃-hydrogenphosphato)di-[mu]-oxido-(1,10-phenanthroline)copper(II)vanadium(V)], [CuV(HPO₄)(H₂PO₄)O₂(C₁₂H₈N₂)]_n, is defined by [(phen)Cu-[mu]-([kappa]²O:O'-VP₂O₁₀H₃)₂-Cu(phen)] units (phen is 1,10-phenanthroline), which are connected to neighbouring units through vanadyl bridges. Neighbouring chains have no covalent bonds between them, although they inter­digitate through the phen groups via [pi]-[pi] inter­actions.

S1. Comment

New materials based on hybrid organic–inorganic compounds are of interest due to their low density compared with pure inorganic materials (Yucesan et al., 2005; Feng & Xu, 2001). Functionalized phosphovanadates have been studied extensively due to their catalytic and magnetic properties. From a catalytic point of view, they are interesting due to the interplay of the different possible oxidation states, and to their high insolubility, which together make them good candidates for heterogeneous catalysis reactions. From a magnetic point of view, they are interesting due to the possibility of being functionalized by secondary paramagnetic complexes.

Vanadium oxides can possess several coordination geometries and therefore present a rich variety of structures by condensation through phosphates Yang et al., 2010; De Burgomaster et al., 2010). The presence of organic ligands can drastically modify these structures. The use of copper(II) as a secondary metal also increases the range of possible structures, due to the structural plasticity of this metal ion (Ushak et al., 2006; Venegas-Yazigi et al., 2011).

The structure of the title compound, (I), is constructed from centrosymmetric (crystallographic) bimetallic [(phen)Cu-µ-(κ²O:O-VP₂O₁₀H₃)₂-Cu(phen)] units (phen is 1,10-phenanthroline), shown in Fig. 1. Within this unit, the Cu^II environment is defined by two N atoms of the phenanthroline ligand [Cu1—N1 = 2.004 (19) and Cu1—N2 = 2.009 (2) Å], two phosphate O atoms [Cu1—O2 = 1.960 (16) and Cu1—O3ⁱ = 1.912 (17) Å; symmetry code: (i) 2 - x, 1 - y, 2 - z] and two vanadyl O atoms [Cu1—O5 = 2.622 (19) and Cu1—O6ⁱⁱ = 2.398 (19) Å; symmetry code: (ii) 1 + x, y, z]. Therefore, the coordination geometry can be described as a slightly distorted octahedron.

The bond-valence sum for the V atom is 5.3, assuming tetrahedral geometry (Brown & Altermatt, 1985). This fits well with the oxidation state of V^V computed from the observed crystal structure. This fact, combined with charge-balance analysis, leads us to establish the phosphovanadate fragments as [VP₂O₁₀H₃]^2-. Both the V^V and P^V atoms within this anion have tetrahedral environments.

The bimetallic unit contains two [Cu(phen)]²⁺ fragments which are bonded through two O—P—O bridges from [VP₂O₁₀H₃]^2- groups. Consequently, the intermetallic distance within the unit is Cu1—Cu1ⁱ = 5.142 (2) Å.

As described above, the coordination environment of each Cu^II centre of the bimetallic [(phen)Cu-µ-(κ²O:O-VP₂O₁₀H₃)₂-Cu(phen)] unit is completed with vanadyl O atoms from neighbouring units. This leads to the formation of a covalent one-dimensional structure growing along the [100] direction. In this way, the chain is formed from two vertex-sharing VO₄ tetrahedra from [VP₂O₁₀H₃]^2- anions connecting consecutive [(phen)Cu-µ-(κ²O:O-VP₂O₁₀H₃)₂-Cu(phen)] units. The phen molecules are oriented perpendicular to the chain direction. The minimum distance between two phen molecules of neighbouring units is the same as the intermetallic Cu1···Cu1ⁱⁱ distance of 7.235 (2) Å.

No covalent bonds exist between neighbouring chains of (I). However, the crystal structure is stabilized by π–π interactions between two adjacent phen molecules of two neighbouring chains, as shown in Fig. 2.

Related literature

For related literature, see: Brown & Altermatt (1985); De Burgomaster, Liu, O'Connor & Zubieta (2010); Feng & Xu (2001); Ushak et al. (2006); Venegas-Yazigi, Brown, Vega, Calvo, Aliaga, Santana, Cardoso-Gil, Kniep, Schnelle & Spodine (2011); Yang et al. (2010); Yucesan et al. (2005).

S2. Experimental

Cupric oxide (CuO; 0.1934 g, 2.43 mmol), 1,10-phenanthroline (phen; 0.0849 g, 0.47 mmol), orthophosphoric acid (H₃PO₄; 0.41 g, 4.2 mmol), sodium vanadate (NaVO₃; 0.0881 g, 1 mmol) and water (H₂O; 10 ml, 555.56 mmol) in a 5.2:1:8.9:1.5:1182 molar ratio were mixed in a Teflon Parr reactor, and then heated at 473 K for 4 d. The pH of the reaction mixture was 1.1. After the reaction solution had cooled down to room temperature, the products were filtered off and dried at 313 K. Rhombohedral green crystals of (I) were separated manually under a microscope. These proved to be of good quality for single-crystal X-ray diffraction (yield 23.6%, based on V). IR (Medium?, ν, cm^-1): bands 1076 (s) and 1000 (m) are assigned to the P—O stretch, the band at 889 (s) is due to the stretching vibrations of the terminal V═O group, 773 (s) is assigned to the V—O—V stretching vibrations, 731 (w), 511 (w) and 413 (w) correspond to the stretching vibrations of the V—O or V—O—P bonds, and 1610 (m), 1601 (m) and 1473 (s) correspond to the organic ligand 1,10-phenanthroline. Analysis, calculated for C₁₂H₁₁CuN₂O₁₀P₂V: C 27.74, H 2.13, N 5.39%; found: C 26.5, H 2.2, N 5.9%.

S3. Refinement

The H-atom positions were calculated after each cycle of refinement using a riding model, with C—H = 0.93 Å, and with U_iso(H) = 1.2U_eq. Efforts to locate the phosphovanadate H atoms in the final Fourier difference map were unsuccessful; those reported for the formula are based on charge-balance analysis. During the last stages of refinement, some disorder was evident on the position of the atom O10, which bonds a vanadyl and a phosphate group. This is reasonable, since the terminal PO₄ group has no other covalent bond. The disorder was modelled by introducing two positions for O10, A and B, and their occupancies were subsequently refined subject to the condition that they summed to 1. When it was clear that the occupancies had reached constant values, at 0.60 and 0.40 for A and B, respectively, the values were set constant for the final refinement stages.

Computing details

Data collection: SMART-NT (Bruker, 2001); cell refinement: SAINT-NT (Bruker, 1999); data reduction: SAINT-NT (Bruker, 1999); program(s) used to solve structure: SHELXTL-NT (Sheldrick, 2008); program(s) used to refine structure: SHELXTL-NT (Sheldrick, 2008); molecular graphics: SHELXTL-NT (Sheldrick, 2008) and ORTEPIII (Farrugia 1997); software used to prepare material for publication: SHELXTL-NT (Sheldrick, 2008).

Figures

	Fig. 1. The molecular structure of the centrosymmetric bimetallic [(phen)Cu-µ-(κ^2O:O-VP2O10H3)2-Cu(phen)] unit of (I). Displacement ellipsoids are drawn at the 50% probability level. The minor disorder component of atom O10 has been omitted for clarity. [Symmetry codes: (i) 2 - x, 1 - y, 2 - z; (ii) 1 + x, y, z.
	Fig. 2. Chains of [(phen)Cu-µ-(κ^2O:O-VP2O10H3)2-Cu(phen)]n running along [100]. The zipped pattern between neigbouring chains is shown. The minor disorder component of atom O10 has been omitted for clarity. [Please revise with all cell axis labels visible]

poly[(dihydrogenphosphato-κO)(µ₃-hydrogenphosphato)di-µ-oxido- (1,10-phenanthroline)copper(II)vanadium(V)]

Crystal data

[CuV(HPO4)(H2PO4)O2(C12H8N2)]	Z = 2
Mr = 519.66	F(000) = 512
Triclinic, P1	Dx = 1.991 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.2350 (14) Å	Cell parameters from 600 reflections
b = 10.705 (2) Å	θ = 2.5–22.1°
c = 11.624 (2) Å	µ = 2.02 mm^−1
α = 75.25 (3)°	T = 293 K
β = 82.58 (3)°	Polyhedron, green
γ = 84.91 (3)°	0.21 × 0.11 × 0.09 mm
V = 861.9 (3) Å^3

Data collection

Siemens SMART CCD area-detector diffractometer	3031 independent reflections
Radiation source: fine-focus sealed tube	2737 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ϕ and ω scans	θmax = 25.0°, θmin = 3.2°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −8→8
Tmin = 0.56, Tmax = 0.80	k = −12→12
16352 measured reflections	l = −13→13

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)] = 0.026	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.076	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0402P)^2 + 1.0381P] where P = (Fo^2 + 2Fc^2)/3
3031 reflections	(Δ/σ)max = 0.001
262 parameters	Δρmax = 0.76 e Å^−3
0 restraints	Δρmin = −0.49 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	Occ. (<1)
Cu1	1.12123 (4)	0.63888 (3)	0.79354 (3)	0.02349 (11)
V1	0.64322 (6)	0.62598 (4)	0.83604 (4)	0.02653 (13)
P1	0.92146 (9)	0.38207 (6)	0.92512 (6)	0.02031 (15)
P2	0.57687 (10)	0.80389 (6)	1.03196 (7)	0.02956 (18)
O1	0.7417 (3)	0.46947 (19)	0.91659 (19)	0.0348 (5)
O2	1.0856 (2)	0.45305 (17)	0.85199 (17)	0.0276 (4)
O3	0.9501 (3)	0.32515 (19)	1.05341 (16)	0.0327 (4)
O4	0.9004 (3)	0.2714 (2)	0.86304 (19)	0.0357 (5)
O5	0.7869 (3)	0.6841 (2)	0.7222 (2)	0.0448 (5)
O6	0.4540 (3)	0.6055 (2)	0.7902 (2)	0.0509 (6)
O7	0.3863 (3)	0.86317 (18)	1.0534 (2)	0.0390 (5)
O8	0.6202 (3)	0.7018 (2)	1.1470 (2)	0.0576 (7)
O9	0.7233 (3)	0.9043 (2)	1.0087 (3)	0.0721 (10)
O10A	0.5764 (11)	0.7266 (9)	0.9405 (9)	0.0552 (19)	0.60
O10B	0.6308 (15)	0.7593 (12)	0.9169 (12)	0.041 (2)	0.40
N1	1.1515 (3)	0.8276 (2)	0.7169 (2)	0.0276 (5)
N2	1.1869 (3)	0.6241 (2)	0.62461 (19)	0.0262 (5)
C1	1.2038 (4)	0.5192 (3)	0.5823 (3)	0.0361 (7)
H1	1.1742	0.4401	0.6341	0.043*
C2	1.2648 (5)	0.5238 (3)	0.4622 (3)	0.0456 (8)
H2	1.2780	0.4485	0.4353	0.055*
C3	1.3049 (5)	0.6395 (4)	0.3851 (3)	0.0450 (8)
H3	1.3452	0.6432	0.3051	0.054*
C4	1.2855 (4)	0.7532 (3)	0.4258 (3)	0.0376 (7)
C5	1.2264 (3)	0.7394 (3)	0.5481 (2)	0.0272 (6)
C6	1.2054 (4)	0.8496 (3)	0.5976 (2)	0.0287 (6)
C7	1.2380 (4)	0.9737 (3)	0.5238 (3)	0.0396 (7)
C8	1.2105 (5)	1.0770 (3)	0.5791 (3)	0.0508 (9)
H8	1.2286	1.1610	0.5340	0.061*
C9	1.1571 (5)	1.0542 (3)	0.6992 (4)	0.0499 (9)
H9	1.1403	1.1224	0.7363	0.060*
C10	1.1278 (4)	0.9276 (3)	0.7663 (3)	0.0379 (7)
H10	1.0906	0.9132	0.8480	0.046*
C11	1.2959 (5)	0.9847 (4)	0.3989 (3)	0.0529 (9)
H11	1.3176	1.0659	0.3485	0.063*
C12	1.3195 (5)	0.8801 (4)	0.3532 (3)	0.0514 (9)
H12	1.3590	0.8907	0.2721	0.062*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.02796 (19)	0.02098 (18)	0.01874 (18)	−0.00315 (12)	0.00142 (12)	−0.00118 (12)
V1	0.0219 (2)	0.0265 (2)	0.0304 (3)	0.00248 (18)	−0.00274 (18)	−0.00707 (19)
P1	0.0212 (3)	0.0189 (3)	0.0196 (3)	−0.0020 (2)	−0.0003 (2)	−0.0031 (2)
P2	0.0263 (4)	0.0176 (3)	0.0424 (4)	0.0009 (3)	0.0042 (3)	−0.0076 (3)
O1	0.0237 (10)	0.0339 (11)	0.0401 (11)	0.0035 (8)	−0.0014 (8)	0.0003 (9)
O2	0.0238 (9)	0.0230 (9)	0.0316 (10)	−0.0037 (7)	0.0014 (8)	−0.0002 (8)
O3	0.0413 (11)	0.0310 (10)	0.0207 (10)	0.0069 (9)	−0.0003 (8)	−0.0018 (8)
O4	0.0344 (11)	0.0390 (11)	0.0403 (12)	−0.0107 (9)	0.0034 (9)	−0.0227 (10)
O5	0.0400 (12)	0.0388 (12)	0.0461 (13)	−0.0007 (10)	0.0074 (10)	0.0002 (10)
O6	0.0297 (11)	0.0508 (14)	0.0717 (17)	0.0000 (10)	−0.0209 (11)	−0.0075 (12)
O7	0.0251 (10)	0.0214 (10)	0.0672 (15)	−0.0005 (8)	0.0039 (10)	−0.0096 (10)
O8	0.0476 (14)	0.0529 (15)	0.0501 (15)	0.0173 (12)	0.0134 (11)	0.0118 (12)
O9	0.0264 (12)	0.0267 (12)	0.152 (3)	−0.0014 (9)	0.0029 (15)	−0.0072 (15)
O10A	0.047 (5)	0.063 (5)	0.064 (5)	0.001 (3)	0.008 (3)	−0.041 (4)
O10B	0.033 (5)	0.039 (5)	0.055 (6)	−0.006 (3)	0.005 (4)	−0.020 (4)
N1	0.0263 (11)	0.0259 (12)	0.0279 (12)	−0.0022 (9)	−0.0025 (9)	−0.0018 (9)
N2	0.0254 (11)	0.0294 (12)	0.0223 (11)	−0.0026 (9)	−0.0025 (9)	−0.0032 (9)
C1	0.0405 (16)	0.0372 (16)	0.0316 (15)	−0.0020 (13)	−0.0049 (13)	−0.0101 (13)
C2	0.055 (2)	0.052 (2)	0.0350 (17)	0.0009 (16)	−0.0058 (15)	−0.0207 (15)
C3	0.0439 (18)	0.067 (2)	0.0239 (15)	−0.0012 (16)	−0.0018 (13)	−0.0135 (15)
C4	0.0314 (15)	0.054 (2)	0.0227 (14)	−0.0041 (14)	−0.0023 (12)	−0.0013 (13)
C5	0.0208 (12)	0.0351 (15)	0.0216 (13)	−0.0035 (11)	−0.0028 (10)	0.0011 (11)
C6	0.0241 (13)	0.0290 (14)	0.0282 (14)	−0.0035 (11)	−0.0029 (11)	0.0025 (11)
C7	0.0374 (16)	0.0325 (16)	0.0402 (17)	−0.0076 (13)	−0.0043 (13)	0.0086 (13)
C8	0.056 (2)	0.0270 (16)	0.061 (2)	−0.0113 (15)	−0.0022 (17)	0.0060 (15)
C9	0.059 (2)	0.0256 (16)	0.066 (2)	−0.0033 (15)	−0.0066 (18)	−0.0119 (16)
C10	0.0437 (17)	0.0298 (15)	0.0397 (17)	−0.0032 (13)	−0.0017 (14)	−0.0085 (13)
C11	0.057 (2)	0.049 (2)	0.0390 (19)	−0.0140 (17)	0.0007 (16)	0.0161 (16)
C12	0.054 (2)	0.064 (2)	0.0254 (16)	−0.0106 (18)	0.0035 (14)	0.0085 (16)

Geometric parameters (Å, º)

Cu1—N1	2.009 (2)	N1—C10	1.327 (4)
Cu1—N2	2.003 (2)	N1—C6	1.357 (4)
Cu1—O2	1.9603 (19)	O6—Cu1^iii	2.399 (2)
Cu1—O3^i	1.9122 (19)	C6—C7	1.407 (4)
Cu1—O5	2.632 (2)	C6—C5	1.428 (4)
Cu1—O6^ii	2.399 (2)	C1—C2	1.398 (4)
V1—O6	1.584 (2)	C1—H1	0.9300
V1—O5	1.600 (2)	C5—C4	1.405 (4)
V1—O10A	1.814 (9)	C7—C8	1.402 (5)
V1—O1	1.831 (2)	C7—C11	1.436 (5)
V1—O10B	1.888 (14)	C4—C3	1.404 (5)
P1—O3	1.494 (2)	C4—C12	1.428 (5)
P1—O2	1.5103 (19)	C2—C3	1.361 (5)
P1—O1	1.532 (2)	C2—H2	0.9300
P1—O4	1.563 (2)	C10—C9	1.400 (4)
P2—O7	1.484 (2)	C10—H10	0.9300
P2—O10A	1.505 (9)	C9—C8	1.364 (5)
P2—O10B	1.526 (14)	C9—H9	0.9300
P2—O9	1.527 (2)	C3—H3	0.9300
P2—O8	1.544 (2)	C8—H8	0.9300
O3—Cu1^i	1.9122 (19)	C12—C11	1.345 (6)
N2—C1	1.326 (4)	C12—H12	0.9300
N2—C5	1.354 (3)	C11—H11	0.9300
O3^i—Cu1—O2	94.30 (9)	C10—N1—Cu1	129.4 (2)
O3^i—Cu1—N2	172.94 (9)	C6—N1—Cu1	111.98 (18)
O2—Cu1—N2	92.16 (9)	V1—O6—Cu1^iii	150.57 (16)
O3^i—Cu1—N1	91.00 (9)	P2—O10A—V1	164.2 (6)
O2—Cu1—N1	173.99 (9)	P2—O10B—V1	148.6 (6)
N2—Cu1—N1	82.42 (10)	N1—C6—C7	123.0 (3)
O3^i—Cu1—O6^ii	102.09 (10)	N1—C6—C5	116.6 (2)
O2—Cu1—O6^ii	92.22 (9)	C7—C6—C5	120.4 (3)
N2—Cu1—O6^ii	80.48 (10)	N2—C1—C2	122.1 (3)
N1—Cu1—O6^ii	89.43 (9)	N2—C1—H1	119.0
O6—V1—O5	108.35 (14)	C2—C1—H1	119.0
O6—V1—O10A	104.9 (3)	N2—C5—C4	123.1 (3)
O5—V1—O10A	116.4 (2)	N2—C5—C6	116.7 (2)
O6—V1—O1	109.28 (12)	C4—C5—C6	120.3 (3)
O5—V1—O1	108.71 (11)	C8—C7—C6	116.7 (3)
O10A—V1—O1	109.0 (3)	C8—C7—C11	125.4 (3)
O6—V1—O10B	115.1 (4)	C6—C7—C11	117.9 (3)
O5—V1—O10B	99.8 (3)	C3—C4—C5	116.5 (3)
O1—V1—O10B	114.9 (4)	C3—C4—C12	125.4 (3)
O3—P1—O2	113.73 (12)	C5—C4—C12	118.1 (3)
O3—P1—O1	109.99 (12)	C3—C2—C1	119.4 (3)
O2—P1—O1	111.08 (11)	C3—C2—H2	120.3
O3—P1—O4	109.67 (12)	C1—C2—H2	120.3
O2—P1—O4	104.23 (11)	N1—C10—C9	122.0 (3)
O1—P1—O4	107.83 (12)	N1—C10—H10	119.0
O7—P2—O10A	108.8 (4)	C9—C10—H10	119.0
O7—P2—O10B	118.8 (5)	C8—C9—C10	119.7 (3)
O10A—P2—O10B	20.8 (3)	C8—C9—H9	120.2
O7—P2—O9	110.99 (12)	C10—C9—H9	120.2
O10A—P2—O9	117.6 (3)	C2—C3—C4	120.3 (3)
O10B—P2—O9	96.8 (3)	C2—C3—H3	119.9
O7—P2—O8	108.39 (13)	C4—C3—H3	119.9
O10A—P2—O8	104.2 (4)	C9—C8—C7	120.0 (3)
O10B—P2—O8	114.4 (5)	C9—C8—H8	120.0
O9—P2—O8	106.33 (18)	C7—C8—H8	120.0
P1—O2—Cu1	130.63 (12)	C11—C12—C4	121.8 (3)
P1—O1—V1	142.85 (13)	C11—C12—H12	119.1
P1—O3—Cu1^i	139.25 (13)	C4—C12—H12	119.1
C1—N2—C5	118.6 (2)	C12—C11—C7	121.5 (3)
C1—N2—Cu1	129.1 (2)	C12—C11—H11	119.3
C5—N2—Cu1	112.23 (18)	C7—C11—H11	119.3
C10—N1—C6	118.6 (2)

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