metal-organic compounds
Bis{(E)-2-[1-(ethoxyimino)ethyl]-1-naphtholato-κ2N,O1}copper(II)
aSchool of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou 730070, People's Republic of China
*Correspondence e-mail: dongwk@126.com
In the title complex, [Cu(C14H14NO2)2], the discrete complex molecules have crystallographic inversion symmetry. The slightly distorted square-planar coordination sphere of the CuII atom comprises two phenolate O atoms and two oxime N atoms from two bidentate–chelate 2-[1-(ethoxyimino)ethyl]-1-naphtholate O-ethyl oxime (L−) ligands [Cu—O = 1.8919 (17) Å and Cu—N = 1.988 (2) Å]. The two naphthalene ring systems in the molecule are parallel, with a perpendicular interplanar spacing of 1.473 (2) Å, while each complex unit forms links to four other molecules via intermolecular methyl C—H⋯π interactions, giving an infinite cross-linked layered supramolecular structure
Related literature
For background to ); Dong et al. (2007, 2008). For related structures, see: Zhao et al. (2009); Dong, Zhao et al. (2009). For the synthesis of the title complex, see: Dong, Tong et al. (2009). For the biological activity of copper(II) complexes, see: Karmaka et al. (2007).
see: Chaudhuri (2003Experimental
Crystal data
|
Refinement
|
Data collection: SMART (Siemens, 1996); cell SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
https://doi.org/10.1107/S1600536810047574/zs2078sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810047574/zs2078Isup2.hkl
1-(1-Hydroxynapthalen-2-yl)ethanone O-ethyl oxime (HL) was synthesized using a method similar to one reported previously (Zhao et al., 2009). Yield, 62.9%. m.p. 315–316 K. Anal. Calcd for C14H15NO2: C, 73.34; H, 6.59; N,6.11%. Found: C, 73.30; H, 6.52; N, 6.22%. A solution of CuII acetate monohydrate (2.5 mg, 0.012 mmol) in methanol (3 ml) was added dropwise to a solution of HL (5.6 mg, 0.023 mmol) and 99% triethylamine (0.025 ml) in methanol (3 ml) at room temperature. The color of the mixing solution turned to yellow immediately, then turned to brown slowly after which the filtrate was allowed to stand at room temperature for about two weeks. The solvent was partially evaporated and brown single crystals suitable for X-ray crystallographic analysis were obtained. Anal. Calcd. for [Cu(L)2] (C28H28CuN2O4): C, 64.66; H, 5.43; N, 5.39; Cu, 12.22%. Found: C, 64.70; H, 5.49; N, 5.33; Cu, 12.20%.
H atoms were placed in calculated positions and non-H atoms were refined anisotropically. H atoms were treated as riding atoms with distances C—H = 0.96 Å (CH3), C—H = 0.97 Å (CH2) and 0.93 Å (CH). The isotropic displacement parameters for all H atoms were set equal to 1.2 or 1.5 Ueq of the carrier atom.
Oxime-type compounds are a versatile class of organic ligands widely used in coordination and analytical chemistry and extraction metallurgy (Dong et al., 2007; Dong et al., 2008; Chaudhuri, 2003). Due to their chelating ability and positive
many copper(II) complexes are generally biologically active (Karmaka et al., 2007). As part of our ongoing research into the transition metal complexes with oxime-type ligands (Dong, Tong et al., 2009), we report here the synthesis and crystal structures of the title CuII complex with 1-(1-hydroxynapthalen-2-yl)ethanone O-ethyl oxime (HL), the title compound [Cu(C14H14NO2)2] (I) (Fig. 1).In the π interactions involving the naphthalene ring C5—C14, with a C3—H3A···π ring centroid separation of 3.715 (2) Å. Thus, every complex molecule forms links with four other adjacent molecules giving an infinite supramolecular layer structure (Fig. 2).
of (I) the discrete complex molecules have inversion symmetry, the slightly distorted square-planar four-coordinate trans-CuN2O2 coordination sphere comprising two phenolic O-atoms and two oxime N-atoms from two bidentate-chelate L- ligands [Cu(1)—O(2), 1.8919 (17) Å; Cu(1)—N(1), 1.988 (2) Å]. These bond distances are within the normal range observed in a similar CuII complex (Dong, Zhao et al., 2009). The two naphthalene rings of the ligands in the complex molecule are parallel with a perpendicular of 1.473 (2) Å. In the the complex molecules are linked by intermolecular methyl C—H···For background to
see: Chaudhuri (2003); Dong et al. (2007); Dong et al. (2008). For related structures, see: Zhao et al. (2009); Dong, Zhao et al. (2009). For the synthesis of the title complex, see: Dong, Tong et al. (2009). For the biological activity of copper(II) complexes, see: Karmaka et al. (2007).Data collection: SMART (Siemens, 1996); cell
SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cu(C14H14NO2)2] | F(000) = 542 |
Mr = 520.06 | Dx = 1.424 Mg m−3 |
Monoclinic, P21/c | Melting point = 315–316 K |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 11.317 (1) Å | Cell parameters from 1730 reflections |
b = 7.1092 (8) Å | θ = 2.7–25.5° |
c = 15.171 (2) Å | µ = 0.94 mm−1 |
β = 96.317 (1)° | T = 298 K |
V = 1213.1 (2) Å3 | Block-like, brown |
Z = 2 | 0.17 × 0.15 × 0.10 mm |
Bruker SMART CCD area-detector diffractometer | 2130 independent reflections |
Radiation source: fine-focus sealed tube | 1490 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.044 |
φ and ω scans | θmax = 25.0°, θmin = 1.8° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −10→13 |
Tmin = 0.857, Tmax = 0.912 | k = −8→8 |
6095 measured reflections | l = −18→18 |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0342P)2] where P = (Fo2 + 2Fc2)/3 |
2130 reflections | (Δ/σ)max < 0.001 |
162 parameters | Δρmax = 0.22 e Å−3 |
0 restraints | Δρmin = −0.21 e Å−3 |
[Cu(C14H14NO2)2] | V = 1213.1 (2) Å3 |
Mr = 520.06 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.317 (1) Å | µ = 0.94 mm−1 |
b = 7.1092 (8) Å | T = 298 K |
c = 15.171 (2) Å | 0.17 × 0.15 × 0.10 mm |
β = 96.317 (1)° |
Bruker SMART CCD area-detector diffractometer | 2130 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1490 reflections with I > 2σ(I) |
Tmin = 0.857, Tmax = 0.912 | Rint = 0.044 |
6095 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.01 | Δρmax = 0.22 e Å−3 |
2130 reflections | Δρmin = −0.21 e Å−3 |
162 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cu1 | 0.5000 | 0.5000 | 0.5000 | 0.03833 (17) | |
N1 | 0.63479 (18) | 0.5872 (3) | 0.58534 (14) | 0.0381 (6) | |
O1 | 0.75134 (16) | 0.6050 (3) | 0.55763 (12) | 0.0514 (6) | |
O2 | 0.39686 (15) | 0.6209 (3) | 0.57215 (12) | 0.0462 (5) | |
C1 | 0.7502 (3) | 0.7498 (5) | 0.49108 (19) | 0.0576 (9) | |
H1A | 0.7131 | 0.8627 | 0.5111 | 0.069* | |
H1B | 0.7052 | 0.7081 | 0.4365 | 0.069* | |
C2 | 0.8761 (3) | 0.7901 (6) | 0.4756 (2) | 0.0789 (12) | |
H2A | 0.9179 | 0.8426 | 0.5284 | 0.118* | |
H2B | 0.8770 | 0.8781 | 0.4277 | 0.118* | |
H2C | 0.9141 | 0.6754 | 0.4608 | 0.118* | |
C3 | 0.7501 (2) | 0.6552 (4) | 0.72791 (18) | 0.0479 (8) | |
H3A | 0.7842 | 0.5401 | 0.7521 | 0.072* | |
H3B | 0.7344 | 0.7376 | 0.7754 | 0.072* | |
H3C | 0.8047 | 0.7149 | 0.6926 | 0.072* | |
C4 | 0.6356 (2) | 0.6131 (4) | 0.67096 (17) | 0.0359 (7) | |
C5 | 0.4124 (2) | 0.6230 (4) | 0.65963 (17) | 0.0371 (7) | |
C6 | 0.5233 (2) | 0.6069 (4) | 0.71082 (17) | 0.0343 (6) | |
C7 | 0.5266 (3) | 0.5992 (4) | 0.80539 (17) | 0.0416 (7) | |
H7 | 0.5994 | 0.5806 | 0.8391 | 0.050* | |
C8 | 0.4279 (3) | 0.6180 (4) | 0.84775 (19) | 0.0468 (8) | |
H8 | 0.4345 | 0.6127 | 0.9093 | 0.056* | |
C9 | 0.3147 (3) | 0.6458 (4) | 0.79925 (19) | 0.0436 (7) | |
C10 | 0.3059 (2) | 0.6458 (4) | 0.70468 (18) | 0.0397 (7) | |
C11 | 0.1938 (3) | 0.6651 (4) | 0.6560 (2) | 0.0525 (9) | |
H11 | 0.1878 | 0.6652 | 0.5944 | 0.063* | |
C12 | 0.0930 (3) | 0.6838 (5) | 0.6976 (2) | 0.0690 (11) | |
H12 | 0.0193 | 0.6941 | 0.6642 | 0.083* | |
C13 | 0.1009 (3) | 0.6873 (5) | 0.7907 (3) | 0.0701 (11) | |
H13 | 0.0324 | 0.7016 | 0.8188 | 0.084* | |
C14 | 0.2079 (3) | 0.6699 (4) | 0.8396 (2) | 0.0597 (9) | |
H14 | 0.2117 | 0.6738 | 0.9012 | 0.072* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0347 (3) | 0.0528 (3) | 0.0283 (3) | −0.0002 (3) | 0.00671 (19) | −0.0033 (3) |
N1 | 0.0276 (12) | 0.0548 (15) | 0.0336 (13) | 0.0001 (11) | 0.0112 (10) | 0.0019 (11) |
O1 | 0.0376 (11) | 0.0795 (16) | 0.0378 (12) | −0.0024 (11) | 0.0064 (9) | 0.0103 (11) |
O2 | 0.0370 (11) | 0.0722 (15) | 0.0297 (11) | 0.0050 (10) | 0.0047 (9) | −0.0089 (10) |
C1 | 0.057 (2) | 0.068 (2) | 0.049 (2) | −0.0095 (18) | 0.0098 (16) | 0.0089 (18) |
C2 | 0.063 (2) | 0.115 (3) | 0.062 (2) | −0.026 (2) | 0.0169 (18) | 0.010 (2) |
C3 | 0.0407 (17) | 0.061 (2) | 0.0410 (17) | −0.0053 (15) | 0.0005 (14) | −0.0029 (15) |
C4 | 0.0426 (17) | 0.0317 (17) | 0.0331 (16) | −0.0011 (13) | 0.0028 (13) | 0.0029 (13) |
C5 | 0.0412 (17) | 0.0341 (17) | 0.0373 (17) | −0.0041 (13) | 0.0106 (13) | −0.0056 (13) |
C6 | 0.0407 (16) | 0.0330 (16) | 0.0304 (15) | −0.0024 (13) | 0.0089 (13) | −0.0023 (13) |
C7 | 0.0496 (18) | 0.0411 (18) | 0.0343 (16) | −0.0036 (15) | 0.0058 (14) | −0.0022 (14) |
C8 | 0.067 (2) | 0.044 (2) | 0.0312 (16) | −0.0051 (16) | 0.0149 (15) | −0.0029 (14) |
C9 | 0.0541 (19) | 0.0359 (18) | 0.0441 (18) | −0.0057 (14) | 0.0203 (15) | −0.0037 (14) |
C10 | 0.0414 (17) | 0.0389 (18) | 0.0407 (17) | −0.0043 (13) | 0.0133 (14) | −0.0066 (13) |
C11 | 0.0437 (19) | 0.070 (2) | 0.0452 (19) | 0.0008 (16) | 0.0136 (15) | −0.0055 (16) |
C12 | 0.047 (2) | 0.095 (3) | 0.067 (3) | 0.0030 (19) | 0.0158 (18) | −0.005 (2) |
C13 | 0.052 (2) | 0.088 (3) | 0.076 (3) | 0.001 (2) | 0.034 (2) | −0.003 (2) |
C14 | 0.077 (2) | 0.058 (2) | 0.050 (2) | −0.0055 (19) | 0.035 (2) | −0.0022 (17) |
Cu1—O2 | 1.8919 (17) | C4—C6 | 1.467 (3) |
Cu1—O2i | 1.8919 (17) | C5—C6 | 1.406 (4) |
Cu1—N1 | 1.988 (2) | C5—C10 | 1.459 (3) |
Cu1—N1i | 1.988 (2) | C6—C7 | 1.432 (3) |
N1—C4 | 1.311 (3) | C7—C8 | 1.355 (3) |
N1—O1 | 1.433 (2) | C7—H7 | 0.9300 |
O1—C1 | 1.441 (3) | C8—C9 | 1.419 (4) |
O2—C5 | 1.320 (3) | C8—H8 | 0.9300 |
C1—C2 | 1.497 (4) | C9—C14 | 1.425 (4) |
C1—H1A | 0.9700 | C9—C10 | 1.427 (4) |
C1—H1B | 0.9700 | C10—C11 | 1.403 (4) |
C2—H2A | 0.9600 | C11—C12 | 1.369 (4) |
C2—H2B | 0.9600 | C11—H11 | 0.9300 |
C2—H2C | 0.9600 | C12—C13 | 1.406 (4) |
C3—C4 | 1.506 (3) | C12—H12 | 0.9300 |
C3—H3A | 0.9600 | C13—C14 | 1.355 (4) |
C3—H3B | 0.9600 | C13—H13 | 0.9300 |
C3—H3C | 0.9600 | C14—H14 | 0.9300 |
O2—Cu1—O2i | 180.00 (8) | C6—C4—C3 | 119.9 (2) |
O2—Cu1—N1 | 87.68 (8) | O2—C5—C6 | 124.6 (2) |
O2i—Cu1—N1 | 92.32 (8) | O2—C5—C10 | 116.5 (2) |
O2—Cu1—N1i | 92.32 (8) | C6—C5—C10 | 118.9 (2) |
O2i—Cu1—N1i | 87.68 (8) | C5—C6—C7 | 118.7 (2) |
N1—Cu1—N1i | 180.0 | C5—C6—C4 | 122.1 (2) |
C4—N1—O1 | 111.8 (2) | C7—C6—C4 | 119.1 (2) |
C4—N1—Cu1 | 127.60 (18) | C8—C7—C6 | 122.6 (3) |
O1—N1—Cu1 | 120.09 (14) | C8—C7—H7 | 118.7 |
N1—O1—C1 | 109.3 (2) | C6—C7—H7 | 118.7 |
C5—O2—Cu1 | 124.36 (17) | C7—C8—C9 | 120.8 (3) |
O1—C1—C2 | 108.1 (3) | C7—C8—H8 | 119.6 |
O1—C1—H1A | 110.1 | C9—C8—H8 | 119.6 |
C2—C1—H1A | 110.1 | C8—C9—C14 | 123.7 (3) |
O1—C1—H1B | 110.1 | C8—C9—C10 | 118.7 (2) |
C2—C1—H1B | 110.1 | C14—C9—C10 | 117.6 (3) |
H1A—C1—H1B | 108.4 | C11—C10—C9 | 119.2 (3) |
C1—C2—H2A | 109.5 | C11—C10—C5 | 120.7 (2) |
C1—C2—H2B | 109.5 | C9—C10—C5 | 120.1 (3) |
H2A—C2—H2B | 109.5 | C12—C11—C10 | 121.2 (3) |
C1—C2—H2C | 109.5 | C12—C11—H11 | 119.4 |
H2A—C2—H2C | 109.5 | C10—C11—H11 | 119.4 |
H2B—C2—H2C | 109.5 | C11—C12—C13 | 120.1 (3) |
C4—C3—H3A | 109.5 | C11—C12—H12 | 120.0 |
C4—C3—H3B | 109.5 | C13—C12—H12 | 120.0 |
H3A—C3—H3B | 109.5 | C14—C13—C12 | 120.2 (3) |
C4—C3—H3C | 109.5 | C14—C13—H13 | 119.9 |
H3A—C3—H3C | 109.5 | C12—C13—H13 | 119.9 |
H3B—C3—H3C | 109.5 | C13—C14—C9 | 121.7 (3) |
N1—C4—C6 | 119.5 (2) | C13—C14—H14 | 119.2 |
N1—C4—C3 | 120.5 (2) | C9—C14—H14 | 119.2 |
O2—Cu1—N1—C4 | 31.5 (2) | C3—C4—C6—C7 | −13.8 (4) |
O2i—Cu1—N1—C4 | −148.5 (2) | C5—C6—C7—C8 | −4.0 (4) |
O2—Cu1—N1—O1 | −157.06 (19) | C4—C6—C7—C8 | 171.1 (3) |
O2i—Cu1—N1—O1 | 22.94 (19) | C6—C7—C8—C9 | 0.3 (5) |
C4—N1—O1—C1 | −122.4 (3) | C7—C8—C9—C14 | −178.8 (3) |
Cu1—N1—O1—C1 | 64.9 (3) | C7—C8—C9—C10 | 2.6 (4) |
N1—Cu1—O2—C5 | −38.7 (2) | C8—C9—C10—C11 | 177.3 (3) |
N1i—Cu1—O2—C5 | 141.3 (2) | C14—C9—C10—C11 | −1.4 (4) |
N1—O1—C1—C2 | 169.7 (2) | C8—C9—C10—C5 | −1.7 (4) |
O1—N1—C4—C6 | 177.8 (2) | C14—C9—C10—C5 | 179.6 (3) |
Cu1—N1—C4—C6 | −10.2 (4) | O2—C5—C10—C11 | −0.3 (4) |
O1—N1—C4—C3 | −0.1 (4) | C6—C5—C10—C11 | 179.0 (3) |
Cu1—N1—C4—C3 | 171.9 (2) | O2—C5—C10—C9 | 178.8 (2) |
Cu1—O2—C5—C6 | 26.8 (4) | C6—C5—C10—C9 | −1.9 (4) |
Cu1—O2—C5—C10 | −153.96 (19) | C9—C10—C11—C12 | 0.0 (5) |
O2—C5—C6—C7 | −176.0 (3) | C5—C10—C11—C12 | 179.0 (3) |
C10—C5—C6—C7 | 4.7 (4) | C10—C11—C12—C13 | 1.2 (5) |
O2—C5—C6—C4 | 8.9 (4) | C11—C12—C13—C14 | −0.8 (6) |
C10—C5—C6—C4 | −170.3 (2) | C12—C13—C14—C9 | −0.7 (5) |
N1—C4—C6—C5 | −16.8 (4) | C8—C9—C14—C13 | −176.9 (3) |
C3—C4—C6—C5 | 161.2 (3) | C10—C9—C14—C13 | 1.7 (5) |
N1—C4—C6—C7 | 168.2 (3) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
Cg1 is the centroid of the C9–C14 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3A···Cg1ii | 0.96 | 2.66 | 3.530 (3) | 151 |
Symmetry code: (ii) −x+1, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Cu(C14H14NO2)2] |
Mr | 520.06 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 11.317 (1), 7.1092 (8), 15.171 (2) |
β (°) | 96.317 (1) |
V (Å3) | 1213.1 (2) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.94 |
Crystal size (mm) | 0.17 × 0.15 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.857, 0.912 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 6095, 2130, 1490 |
Rint | 0.044 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.081, 1.01 |
No. of reflections | 2130 |
No. of parameters | 162 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.22, −0.21 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Cg1 is the centroid of the C9–C14 ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
C3—H3A···Cg1i | 0.96 | 2.66 | 3.530 (3) | 151 |
Symmetry code: (i) −x+1, y−1/2, −z+3/2. |
Acknowledgements
This work was supported by the Foundation of the Education Department of Gansu Province (0904–11), which is gratefully acknowledged.
References
Chaudhuri, P. (2003). Coord. Chem. Rev. 243, 143–168. Web of Science CrossRef CAS Google Scholar
Dong, W.-K., Feng, J.-H. & Yang, X.-Q. (2007). Synth. React. Inorg. Met. Org. Nano-Chem. 37, 189–192. Web of Science CSD CrossRef CAS Google Scholar
Dong, W.-K., Li, L., Li, C.-F., Xu, L. & Duan, J.-G. (2008). Spectrochim. Acta Part A, 71, 650–654. CrossRef Google Scholar
Dong, W.-K., Tong, J.-F., An, L.-L., Wu, J.-C. & Yao, J. (2009). Acta Cryst. E65, m945. Web of Science CSD CrossRef IUCr Journals Google Scholar
Dong, W.-K., Zhao, C.-Y., Sun, Y.-X., Tang, X.-L. & He, X.-N. (2009). Inorg. Chem. Commun. 12, 234–236. Web of Science CSD CrossRef CAS Google Scholar
Karmaka, R., Choudhury, C. R., Batten, S. R. & Mitra, S. (2007). J. Mol. Struct. 826, 75–81. Google Scholar
Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Siemens (1996). SMART and SAINT. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA. Google Scholar
Zhao, L., Dong, W.-K., Wu, J.-C., Sun, Y.-X. & Xu, L. (2009). Acta Cryst. E65, o2462. Web of Science CSD CrossRef IUCr Journals Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
Oxime-type compounds are a versatile class of organic ligands widely used in coordination and analytical chemistry and extraction metallurgy (Dong et al., 2007; Dong et al., 2008; Chaudhuri, 2003). Due to their chelating ability and positive redox potential, many copper(II) complexes are generally biologically active (Karmaka et al., 2007). As part of our ongoing research into the transition metal complexes with oxime-type ligands (Dong, Tong et al., 2009), we report here the synthesis and crystal structures of the title CuII complex with 1-(1-hydroxynapthalen-2-yl)ethanone O-ethyl oxime (HL), the title compound [Cu(C14H14NO2)2] (I) (Fig. 1).
In the crystal structure of (I) the discrete complex molecules have inversion symmetry, the slightly distorted square-planar four-coordinate trans-CuN2O2 coordination sphere comprising two phenolic O-atoms and two oxime N-atoms from two bidentate-chelate L- ligands [Cu(1)—O(2), 1.8919 (17) Å; Cu(1)—N(1), 1.988 (2) Å]. These bond distances are within the normal range observed in a similar CuII complex (Dong, Zhao et al., 2009). The two naphthalene rings of the ligands in the complex molecule are parallel with a perpendicular interplanar spacing of 1.473 (2) Å. In the crystal structure, the complex molecules are linked by intermolecular methyl C—H···π interactions involving the naphthalene ring C5—C14, with a C3—H3A···π ring centroid separation of 3.715 (2) Å. Thus, every complex molecule forms links with four other adjacent molecules giving an infinite supramolecular layer structure (Fig. 2).