metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

Di­aqua­bis­­(2-oxo-2H-chromene-3-carboxyl­ato)copper(II)

aCollege of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, People's Republic of China
*Correspondence e-mail: xieyabo@bjut.edu.cn

(Received 28 April 2011; accepted 17 May 2011; online 20 May 2011)

In the title compound, [Cu(C10H5O4)2(H2O)2], the CuII atom lies on a crystallographic inversion center and exhibits an octa­hedral coordination defined by two O atoms from water mol­ecules in the axial positions and by four O atoms from two deprotonated coumarin-3-carb­oxy­lic acid ligands in the equatorial positions. The angles around the CuII atom vary between 85.32 (6) and 94.68 (6)°. The Cu—O bond distances between the CuII atom and the O atoms vary between 1.9424 (14) and 2.3229 (15) Å. The layers inter­digitate via face-to-face aromatic inter­actions [3.6490 (8) Å] between coumarin moieties such that the inter­layer separation is 10.460 (2) Å, i.e. the length of the c axis. O—H⋯O hydrogen bonds between the H atoms of coordinated water mol­ecules and the O atoms of carboxyl­ate groups link the complex mol­ecules into layers parallel to the ab plane.

Related literature

For background to topological networks, see: Laza­rou et al. (2011[Lazarou, K. N., Psycharis, V., Terzis, A. & Raptopoulou, C. P. (2011). Polyhedron, 30, 963-970.]). For applications of copper(II) complexes, see: Eddaoudi et al. (2001[Eddaoudi, M., Kim, J., Wachter, J. B., Chae, H. K., O'Keeffe, M. & Yaghi, O. M. (2001). J. Am. Chem. Soc. 123, 4368-4369.]); Kirillov et al. (2010[Kirillov, A. M., Coelho, J. A. S., Kirillov, M. V., Guedes da Silva, M. F. C., Nesterov, D. S., Gruenwald, K. R., Haukka, M. & Pombeiro, A. J. L. (2010). Inorg. Chem. 49, 6390-6392.]); Konidaris et al. (2009[Konidaris, K. F., Papaefstathiou, G. S., Aromi, G., Teat, S. J., Manessi-Zoupa, E., Escuer, A. & Perlepes, S. P. (2009). Polyhedron, 28, 1646-1651.]). For related structures, see: Wang et al. (2011[Wang, X. L., Lin, H. Y., Mu, B., Tian, A. X., Liu, G. C. & Hu, N. H. (2011). CrystEngComm, 13, 1990-1997.]).

[Scheme 1]

Experimental

Crystal data
  • [Cu(C10H5O4)2(H2O)2]

  • Mr = 477.86

  • Triclinic, [P \overline 1]

  • a = 6.5884 (13) Å

  • b = 6.8296 (14) Å

  • c = 10.460 (2) Å

  • α = 85.98 (3)°

  • β = 89.79 (3)°

  • γ = 65.38 (3)°

  • V = 426.65 (15) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 1.35 mm−1

  • T = 293 K

  • 0.20 × 0.15 × 0.15 mm

Data collection
  • Bruker APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2008a[Sheldrick, G. M. (2008a). SADABS. University of Göttingen, Germany.]) Tmin = 0.785, Tmax = 0.817

  • 2696 measured reflections

  • 1954 independent reflections

  • 1926 reflections with I > 2σ(I)

  • Rint = 0.014

Refinement
  • R[F2 > 2σ(F2)] = 0.026

  • wR(F2) = 0.080

  • S = 1.10

  • 1954 reflections

  • 146 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.47 e Å−3

  • Δρmin = −0.59 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1W—H1WA⋯O4i 0.82 1.89 2.706 (2) 177
O1W—H1WB⋯O4ii 0.88 (3) 1.90 (3) 2.753 (2) 163 (3)
Symmetry codes: (i) -x, -y, -z+1; (ii) x+1, y-1, z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008b[Sheldrick, G. M. (2008b). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In the past decades, numerous papers dealing with copper(II) complexes have been published due to their fascinating structural diversity (Lazarou et al., 2011) and potential applications in the areas of catalysis (Kirillov et al., 2010), gas addsorption (Eddaoudi et al., 2001), magnetism (Konidaris et al., 2009) and so on. Herein, we report the synthesis and crystal structure of a new mononuclear copper complex coordinated by coumarin-3-carboxylic acid.

In the title compound, [Cu(C10H5O4)2(H2O)2], copper(II) atom lies on a crystallographic inversion center and exhibits octahedral geometry with the coordination of two O atoms from water molecules in the axial positions and four O atoms from two deprotonated coumarin-3-carboxylic acid ligands in the equatorial positions. Angles around the CuII atom vary between 85.32 (6)° and 94.68 (6)°. The Cu—O bond distances between the CuII atom and the O atoms vary between 1.9424 (14) and 2.3229 (15) Å, all of which are comparable to those reported for other copper-oxygen donor complexes (e.g., Wang et al., 2011). The (C2C1C3C4C5C6) ring and the (C4C3C7C9C8O2) ring are almost coplanar, and the dihedral angles is 1.568 (57)°. The layers interdigitate via face to face aromatic interactions (distance 3.6490 (8) Å) between coumarin moieties such that the interlayer separation is 10.46 Å, length of c axis. O—H···O hydrogen bonds between the hydrogen atoms of coordinated water molecules and the O atoms of carboxylate groups joins the complexes into two-dimensional layers parallel the ab plane (Table 1 and Fig. 2).

Related literature top

For background to topological networks, see: Lazarou et al. (2011). For applications of copper(II) complexes, see: Eddaoudi et al. (2001); Kirillov et al. (2010); Konidaris et al. (2009). For related structures, see: Wang et al. (2011).

Experimental top

The title complex was synthesized by carefully layering a solution of Cu(NO3)2.3H2O (24.2 mg, 0.1 mmol) in ethanol (10 ml) on top of a solution of coumarin-3-carboxylic acid (19.0 mg, 0.1 mmol) and LiOH (8.4 mg, 0.2 mmol) in H2O (10 ml) in a test-tube. After about one month at room temperature, green block-shaped single crystals suitable for X-ray investigation appeared at the boundary between the ethanol solution and the water layer with a yield of 25% (12.1 mg). FT—IR (KBr, cm-1): 788, 1028, 1183, 1285, 1388, 1457, 1560, 1697, 3180.

Refinement top

Carbon H atoms were placed geometrically (C—H = 0.93 Å) and treated as riding with Uiso(H) = 1.2Ueq(C). Water H atoms were located in calculated positions and treated in the subsequent refinement as riding atoms, with O—H = 0.85 Å and Uiso(H) = 1.5Ueq(O).

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b); molecular graphics: SHELXTL (Sheldrick, 2008b); software used to prepare material for publication: SHELXTL (Sheldrick, 2008b).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level for non-hydrogen atoms, hydrogen atoms are shown as small circles of arbitrary radius. [Symmetry code: i = -x + 1, -y, -z + 1].
[Figure 2] Fig. 2. Partial packing view of title compound, showing the formation of network built from hydrogen bonds.
Diaquabis(2-oxo-2H-chromene-3-carboxylato)copper(II) top
Crystal data top
[Cu(C10H5O4)2(H2O)2]Z = 1
Mr = 477.86F(000) = 243
Triclinic, P1Dx = 1.860 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 6.5884 (13) ÅCell parameters from 2273 reflections
b = 6.8296 (14) Åθ = 3.3–28.3°
c = 10.460 (2) ŵ = 1.35 mm1
α = 85.98 (3)°T = 293 K
β = 89.79 (3)°Block, green
γ = 65.38 (3)°0.20 × 0.15 × 0.15 mm
V = 426.65 (15) Å3
Data collection top
Bruker APEXII CCD
diffractometer
1954 independent reflections
Radiation source: fine-focus sealed tube1926 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.014
ϕ and ω scansθmax = 28.3°, θmin = 3.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
h = 88
Tmin = 0.785, Tmax = 0.817k = 68
2696 measured reflectionsl = 1213
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)] = 0.026Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.080H atoms treated by a mixture of independent and constrained refinement
S = 1.10 w = 1/[σ2(Fo2) + (0.0426P)2 + 0.4127P]
where P = (Fo2 + 2Fc2)/3
1954 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 0.47 e Å3
0 restraintsΔρmin = 0.59 e Å3
Crystal data top
[Cu(C10H5O4)2(H2O)2]γ = 65.38 (3)°
Mr = 477.86V = 426.65 (15) Å3
Triclinic, P1Z = 1
a = 6.5884 (13) ÅMo Kα radiation
b = 6.8296 (14) ŵ = 1.35 mm1
c = 10.460 (2) ÅT = 293 K
α = 85.98 (3)°0.20 × 0.15 × 0.15 mm
β = 89.79 (3)°
Data collection top
Bruker APEXII CCD
diffractometer
1954 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008a)
1926 reflections with I > 2σ(I)
Tmin = 0.785, Tmax = 0.817Rint = 0.014
2696 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0260 restraints
wR(F2) = 0.080H atoms treated by a mixture of independent and constrained refinement
S = 1.10Δρmax = 0.47 e Å3
1954 reflectionsΔρmin = 0.59 e Å3
146 parameters
Special details top

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 (Å2) top
xyzUiso*/Ueq
Cu10.50000.00000.50000.00966 (11)
O10.4519 (2)0.1657 (2)0.69122 (12)0.0146 (3)
O1W0.4903 (2)0.2639 (2)0.59038 (12)0.0126 (3)
H1WA0.39290.29000.55680.019*
O30.1764 (2)0.1397 (2)0.48277 (12)0.0124 (3)
O40.1736 (2)0.3644 (2)0.51356 (12)0.0127 (3)
O20.3051 (2)0.1949 (2)0.88105 (12)0.0122 (3)
C10.2504 (3)0.2859 (3)1.00004 (18)0.0135 (3)
H1A0.39040.30430.96990.016*
C20.2116 (3)0.2857 (3)1.13001 (18)0.0155 (4)
H2A0.32640.30681.18690.019*
C30.0782 (3)0.2581 (3)0.91346 (17)0.0112 (3)
C40.1306 (3)0.2267 (3)0.96207 (17)0.0113 (3)
C50.1731 (3)0.2237 (3)1.09260 (17)0.0139 (3)
H5A0.31380.20191.12310.017*
C60.0000 (3)0.2539 (3)1.17600 (17)0.0154 (4)
H6A0.02490.25301.26350.019*
C70.1071 (3)0.2648 (3)0.77726 (17)0.0111 (3)
H7A0.24570.28710.74290.013*
C80.2831 (3)0.1975 (3)0.75042 (17)0.0110 (3)
C90.0633 (3)0.2392 (3)0.69730 (17)0.0103 (3)
C100.0214 (3)0.2495 (3)0.55452 (17)0.0103 (3)
H1WB0.614 (5)0.377 (5)0.577 (3)0.035 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.00616 (16)0.01127 (16)0.00921 (16)0.00141 (11)0.00012 (10)0.00028 (11)
O10.0097 (6)0.0224 (7)0.0120 (6)0.0065 (5)0.0005 (5)0.0029 (5)
O1W0.0094 (6)0.0135 (6)0.0130 (6)0.0029 (5)0.0002 (5)0.0003 (5)
O30.0089 (6)0.0157 (6)0.0103 (6)0.0025 (5)0.0001 (5)0.0018 (5)
O40.0086 (6)0.0143 (6)0.0127 (6)0.0022 (5)0.0018 (5)0.0006 (5)
O20.0096 (6)0.0166 (6)0.0098 (6)0.0050 (5)0.0007 (5)0.0010 (5)
C10.0118 (8)0.0129 (8)0.0143 (8)0.0039 (6)0.0025 (7)0.0001 (6)
C20.0183 (9)0.0130 (8)0.0132 (8)0.0046 (7)0.0052 (7)0.0004 (6)
C30.0112 (8)0.0095 (7)0.0113 (8)0.0029 (6)0.0010 (6)0.0004 (6)
C40.0121 (8)0.0096 (7)0.0106 (8)0.0030 (6)0.0017 (6)0.0007 (6)
C50.0157 (9)0.0124 (8)0.0120 (8)0.0044 (7)0.0032 (7)0.0000 (6)
C60.0221 (10)0.0123 (8)0.0097 (8)0.0050 (7)0.0005 (7)0.0005 (6)
C70.0094 (8)0.0104 (8)0.0122 (8)0.0031 (6)0.0005 (6)0.0003 (6)
C80.0113 (8)0.0102 (7)0.0103 (8)0.0033 (6)0.0012 (6)0.0006 (6)
C90.0091 (8)0.0100 (7)0.0107 (8)0.0030 (6)0.0009 (6)0.0005 (6)
C100.0092 (8)0.0099 (7)0.0117 (8)0.0039 (6)0.0007 (6)0.0001 (6)
Geometric parameters (Å, º) top
Cu1—O3i1.9424 (14)C1—C31.408 (2)
Cu1—O31.9424 (14)C1—H1A0.9300
Cu1—O1Wi2.0007 (14)C2—C61.400 (3)
Cu1—O1W2.0007 (14)C2—H2A0.9300
Cu1—O12.3229 (15)C3—C41.393 (3)
Cu1—O1i2.3229 (15)C3—C71.433 (2)
O1—C81.216 (2)C4—C51.392 (2)
O1W—H1WA0.8200C5—C61.388 (3)
O1W—H1WB0.88 (3)C5—H5A0.9300
O3—C101.266 (2)C6—H6A0.9300
O4—C101.251 (2)C7—C91.357 (2)
O2—C81.373 (2)C7—H7A0.9300
O2—C41.377 (2)C8—C91.459 (2)
C1—C21.384 (3)C9—C101.511 (2)
O3i—Cu1—O3180.0C6—C2—H2A119.9
O3i—Cu1—O1Wi91.47 (6)C4—C3—C1118.49 (16)
O3—Cu1—O1Wi88.53 (6)C4—C3—C7118.02 (16)
O3i—Cu1—O1W88.53 (6)C1—C3—C7123.47 (17)
O3—Cu1—O1W91.47 (6)O2—C4—C5117.36 (16)
O1Wi—Cu1—O1W180.0O2—C4—C3120.44 (16)
O3i—Cu1—O194.68 (6)C5—C4—C3122.19 (17)
O3—Cu1—O185.32 (6)C6—C5—C4118.29 (18)
O1Wi—Cu1—O188.76 (6)C6—C5—H5A120.9
O1W—Cu1—O191.24 (6)C4—C5—H5A120.9
O3i—Cu1—O1i85.32 (6)C5—C6—C2120.83 (17)
O3—Cu1—O1i94.68 (6)C5—C6—H6A119.6
O1Wi—Cu1—O1i91.24 (6)C2—C6—H6A119.6
O1W—Cu1—O1i88.76 (6)C9—C7—C3121.45 (17)
O1—Cu1—O1i180.0C9—C7—H7A119.3
C8—O1—Cu1118.65 (12)C3—C7—H7A119.3
Cu1—O1W—H1WA109.5O1—C8—O2115.47 (16)
Cu1—O1W—H1WB110 (2)O1—C8—C9127.02 (16)
H1WA—O1W—H1WB103.7O2—C8—C9117.51 (15)
C10—O3—Cu1134.40 (12)C7—C9—C8119.69 (16)
C8—O2—C4122.81 (14)C7—C9—C10118.84 (16)
C2—C1—C3120.02 (18)C8—C9—C10121.45 (15)
C2—C1—H1A120.0O4—C10—O3122.88 (16)
C3—C1—H1A120.0O4—C10—C9116.53 (15)
C1—C2—C6120.16 (17)O3—C10—C9120.53 (16)
C1—C2—H2A119.9
O3i—Cu1—O1—C8149.14 (14)C1—C2—C6—C50.5 (3)
O3—Cu1—O1—C830.86 (14)C4—C3—C7—C90.7 (3)
O1Wi—Cu1—O1—C8119.49 (14)C1—C3—C7—C9179.37 (17)
O1W—Cu1—O1—C860.51 (14)Cu1—O1—C8—O2149.88 (11)
O1Wi—Cu1—O3—C1095.25 (17)Cu1—O1—C8—C930.6 (2)
O1W—Cu1—O3—C1084.75 (17)C4—O2—C8—O1179.60 (15)
O1—Cu1—O3—C106.37 (17)C4—O2—C8—C90.9 (2)
O1i—Cu1—O3—C10173.63 (17)C3—C7—C9—C81.8 (3)
C3—C1—C2—C61.2 (3)C3—C7—C9—C10179.55 (15)
C2—C1—C3—C41.2 (3)O1—C8—C9—C7177.91 (18)
C2—C1—C3—C7177.46 (16)O2—C8—C9—C72.6 (2)
C8—O2—C4—C5179.00 (15)O1—C8—C9—C100.7 (3)
C8—O2—C4—C31.7 (3)O2—C8—C9—C10178.83 (15)
C1—C3—C4—O2178.78 (15)Cu1—O3—C10—O4163.62 (13)
C7—C3—C4—O22.5 (3)Cu1—O3—C10—C919.1 (3)
C1—C3—C4—C50.5 (3)C7—C9—C10—O428.9 (2)
C7—C3—C4—C5178.26 (16)C8—C9—C10—O4152.53 (17)
O2—C4—C5—C6179.54 (16)C7—C9—C10—O3148.55 (17)
C3—C4—C5—C60.2 (3)C8—C9—C10—O330.0 (2)
C4—C5—C6—C20.3 (3)
Symmetry code: (i) x+1, y, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O4ii0.821.892.706 (2)177
O1W—H1WB···O4iii0.88 (3)1.90 (3)2.753 (2)163 (3)
Symmetry codes: (ii) x, y, z+1; (iii) x+1, y1, z.

Experimental details

Crystal data
Chemical formula[Cu(C10H5O4)2(H2O)2]
Mr477.86
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)6.5884 (13), 6.8296 (14), 10.460 (2)
α, β, γ (°)85.98 (3), 89.79 (3), 65.38 (3)
V3)426.65 (15)
Z1
Radiation typeMo Kα
µ (mm1)1.35
Crystal size (mm)0.20 × 0.15 × 0.15
Data collection
DiffractometerBruker APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2008a)
Tmin, Tmax0.785, 0.817
No. of measured, independent and
observed [I > 2σ(I)] reflections
2696, 1954, 1926
Rint0.014
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.026, 0.080, 1.10
No. of reflections1954
No. of parameters146
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.47, 0.59

Computer programs: APEX2 (Bruker, 2008), SAINT (Bruker, 2008), SHELXS97 (Sheldrick, 2008b), SHELXL97 (Sheldrick, 2008b), SHELXTL (Sheldrick, 2008b).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1W—H1WA···O4i0.821.892.706 (2)177
O1W—H1WB···O4ii0.88 (3)1.90 (3)2.753 (2)163 (3)
Symmetry codes: (i) x, y, z+1; (ii) x+1, y1, z.
 

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. 21075114), the Special Environmental Protection Fund for Public Welfare project (201009015) and the Funding Project for Academic Human Resources Development in Institutions of Higher Learning under the jurisdiction of the Beijing Municipality (PHR 201107104).

References

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COMMUNICATIONS
ISSN: 2056-9890
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