Acta Cryst. (2007). E63, m2397 [ doi:10.1107/S1600536807040585 ]
The title compound, [Cu(C8H7O4)2(C3H7NO)2], is a mononuclear copper(II) complex where the CuII atom, lying on an inversion center, is coordinated in elongated octahedral fashion by six O atoms, four from two 3-acetyl-6-methyl-2-oxo-2H-pyran-4-olate ligands in equatorial positions and the remaining two from dimethylformamide molecules in axial positions.
To a solution of copper acetate monohydrate is added, with stirring a solution of dehydroacetic acid in absolute ethanol with a 1:2 stoichiometric ratio. Complex (I) precipitated after one hour. The precipitate was filtered and recrystallized by slow evaporation in a dimethylsulfoxide solution.
Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Nonius, 1998); data reduction: DENZO (Nonius, 1998); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ATOMS (Dowty, 1995); software used to prepare material for publication: PLATON (Spek, 2003).
![[Figure 1]](./bg2087fig1thm.gif)
| Fig. 1. ORTEP view of a selected part of the crystal structure of compound 2. The ellipsoids enclose 30% of the electronic density. Symmetry operators for generating equivalent positions: (i) −x,-y,-z. |
![[Figure 2]](./bg2087fig2thm.gif)
| Fig. 2. View of the crystal structure of Cu(DHA)2(DMF)2 (I) in the (b,c) plane. The hydrogen atoms have been omitted for clarity. |
| [Cu(C8H7O4)2(C3H7NO)2] | Z = 1 |
| Mr = 544.01 | F000 = 283.00 |
| Triclinic, P1 | Dx = 1.501 Mg m−3 |
| Hall symbol: -P 1 | Mo Kα radiation λ = 0.71069 Å |
| a = 7.6894 (2) Å | Cell parameters from 4486 reflections |
| b = 8.5406 (2) Å | θ = 1.0–30.0º |
| c = 9.3858 (3) Å | µ = 0.97 mm−1 |
| α = 84.8700 (10)º | T = 173 (2) K |
| β = 86.9640 (10)º | Prism, blue |
| γ = 78.852 (2)º | 0.10 × 0.10 × 0.10 mm |
| V = 601.93 (3) Å3 |
| Nonius KappaCCD diffractometer | 3021 reflections with I > 2σ(I) |
| Radiation source: fine-focus sealed tube | Rint = 0.050 |
| Monochromator: graphite | θmax = 30.1º |
| T = 173(2) K | θmin = 2.2º |
| π [CHECK] scans | h = −10→10 |
| Absorption correction: none | k = −12→11 |
| 8024 measured reflections | l = −13→13 |
| 3518 independent reflections |
| Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
| Least-squares matrix: full | H-atom parameters constrained |
| R[F2 > 2σ(F2)] = 0.037 | w = 1/[σ2(Fo2) + (0.0542P)2 + 0.0974P] where P = (Fo2 + 2Fc2)/3 |
| wR(F2) = 0.103 | (Δ/σ)max < 0.001 |
| S = 1.05 | Δρmax = 0.36 e Å−3 |
| 3518 reflections | Δρmin = −0.55 e Å−3 |
| 161 parameters | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
| Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.221 (11) |
| Secondary atom site location: difference Fourier map |
| [Cu(C8H7O4)2(C3H7NO)2] | γ = 78.852 (2)º |
| Mr = 544.01 | V = 601.93 (3) Å3 |
| Triclinic, P1 | Z = 1 |
| a = 7.6894 (2) Å | Mo Kα |
| b = 8.5406 (2) Å | µ = 0.97 mm−1 |
| c = 9.3858 (3) Å | T = 173 (2) K |
| α = 84.8700 (10)º | 0.10 × 0.10 × 0.10 mm |
| β = 86.9640 (10)º |
| Nonius KappaCCD diffractometer | 3518 independent reflections |
| Absorption correction: none | 3021 reflections with I > 2σ(I) |
| 8024 measured reflections | Rint = 0.050 |
| R[F2 > 2σ(F2)] = 0.037 | 161 parameters |
| wR(F2) = 0.103 | H-atom parameters constrained |
| S = 1.05 | Δρmax = 0.36 e Å−3 |
| 3518 reflections | Δρmin = −0.55 e Å−3 |
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 > 2sigma(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 | 0.0000 | 0.0000 | 0.0000 | 0.03279 (12) | |
| O1 | −0.09598 (15) | −0.06122 (16) | 0.18483 (12) | 0.0368 (3) | |
| O2 | 0.15683 (17) | −0.26020 (18) | 0.54467 (13) | 0.0438 (3) | |
| O3 | 0.41095 (18) | −0.1951 (2) | 0.47529 (15) | 0.0534 (4) | |
| O4 | 0.21496 (15) | 0.02621 (16) | 0.08599 (13) | 0.0375 (3) | |
| O5 | 0.1369 (2) | −0.28176 (19) | −0.01498 (18) | 0.0560 (4) | |
| N1 | 0.3220 (2) | −0.47067 (19) | −0.13276 (18) | 0.0420 (3) | |
| C1 | −0.0075 (2) | −0.1174 (2) | 0.29462 (16) | 0.0304 (3) | |
| C2 | −0.1011 (2) | −0.1903 (2) | 0.41121 (18) | 0.0379 (4) | |
| H2 | −0.2243 | −0.1887 | 0.4047 | 0.045* | |
| C3 | −0.0181 (2) | −0.2601 (2) | 0.52813 (18) | 0.0381 (4) | |
| C4 | 0.2594 (2) | −0.1858 (2) | 0.44211 (18) | 0.0367 (4) | |
| C5 | 0.1755 (2) | −0.1125 (2) | 0.31181 (16) | 0.0298 (3) | |
| C6 | 0.2740 (2) | −0.0303 (2) | 0.20597 (17) | 0.0318 (3) | |
| C7 | 0.4565 (2) | −0.0019 (3) | 0.2306 (2) | 0.0502 (5) | |
| H7A | 0.4933 | 0.0685 | 0.1513 | 0.075* | |
| H7B | 0.5402 | −0.1044 | 0.2362 | 0.075* | |
| H7C | 0.4551 | 0.0485 | 0.3205 | 0.075* | |
| C8 | −0.0964 (3) | −0.3446 (3) | 0.6534 (2) | 0.0540 (5) | |
| H8A | −0.0298 | −0.4546 | 0.6676 | 0.081* | |
| H8B | −0.2205 | −0.3466 | 0.6361 | 0.081* | |
| H8C | −0.0903 | −0.2885 | 0.7391 | 0.081* | |
| C9 | 0.2491 (2) | −0.3213 (2) | −0.1090 (2) | 0.0417 (4) | |
| H9 | 0.2869 | −0.2382 | −0.1697 | 0.050* | |
| C10 | 0.4528 (3) | −0.5079 (3) | −0.2474 (3) | 0.0623 (6) | |
| H10A | 0.4087 | −0.5726 | −0.3135 | 0.093* | |
| H10B | 0.5635 | −0.5680 | −0.2074 | 0.093* | |
| H10C | 0.4747 | −0.4083 | −0.2992 | 0.093* | |
| C11 | 0.2675 (4) | −0.6042 (3) | −0.0473 (3) | 0.0635 (6) | |
| H11A | 0.3720 | −0.6746 | −0.0060 | 0.095* | |
| H11B | 0.2091 | −0.6645 | −0.1080 | 0.095* | |
| H11C | 0.1847 | −0.5638 | 0.0299 | 0.095* |
| U11 | U22 | U33 | U12 | U13 | U23 | |
| Cu1 | 0.02832 (16) | 0.0447 (2) | 0.02637 (16) | −0.01107 (11) | −0.00577 (10) | 0.00369 (11) |
| O1 | 0.0273 (5) | 0.0532 (8) | 0.0289 (5) | −0.0080 (5) | −0.0048 (4) | 0.0048 (5) |
| O2 | 0.0425 (7) | 0.0554 (8) | 0.0313 (6) | −0.0085 (6) | −0.0059 (5) | 0.0095 (5) |
| O3 | 0.0409 (7) | 0.0749 (11) | 0.0439 (7) | −0.0139 (7) | −0.0169 (6) | 0.0137 (7) |
| O4 | 0.0335 (6) | 0.0486 (7) | 0.0324 (6) | −0.0156 (5) | −0.0079 (4) | 0.0073 (5) |
| O5 | 0.0567 (9) | 0.0460 (8) | 0.0641 (10) | −0.0085 (7) | 0.0111 (7) | −0.0096 (7) |
| N1 | 0.0425 (8) | 0.0368 (8) | 0.0455 (8) | −0.0090 (6) | 0.0026 (6) | 0.0027 (6) |
| C1 | 0.0298 (7) | 0.0340 (8) | 0.0272 (7) | −0.0052 (6) | −0.0016 (5) | −0.0038 (6) |
| C2 | 0.0331 (8) | 0.0478 (10) | 0.0323 (8) | −0.0088 (7) | −0.0002 (6) | 0.0004 (7) |
| C3 | 0.0397 (9) | 0.0424 (10) | 0.0310 (8) | −0.0072 (7) | 0.0017 (6) | −0.0003 (7) |
| C4 | 0.0363 (8) | 0.0410 (9) | 0.0313 (8) | −0.0043 (7) | −0.0066 (6) | 0.0017 (7) |
| C5 | 0.0300 (7) | 0.0327 (8) | 0.0268 (7) | −0.0053 (6) | −0.0055 (5) | −0.0012 (6) |
| C6 | 0.0295 (7) | 0.0344 (8) | 0.0323 (7) | −0.0071 (6) | −0.0066 (6) | −0.0020 (6) |
| C7 | 0.0373 (9) | 0.0687 (14) | 0.0480 (11) | −0.0236 (9) | −0.0146 (8) | 0.0141 (9) |
| C8 | 0.0571 (12) | 0.0634 (14) | 0.0396 (10) | −0.0150 (10) | 0.0045 (9) | 0.0101 (9) |
| C9 | 0.0386 (9) | 0.0372 (9) | 0.0508 (10) | −0.0123 (7) | −0.0046 (8) | 0.0008 (8) |
| C10 | 0.0601 (14) | 0.0568 (14) | 0.0621 (14) | 0.0010 (10) | 0.0158 (11) | 0.0008 (11) |
| C11 | 0.0718 (15) | 0.0436 (12) | 0.0736 (16) | −0.0164 (10) | 0.0133 (12) | 0.0061 (11) |
| Cu1—O1 | 1.9181 (11) | C3—C8 | 1.486 (3) |
| Cu1—O4 | 1.9366 (12) | C4—C5 | 1.447 (2) |
| Cu1—O5 | 2.4462 (16) | C5—C6 | 1.433 (2) |
| Cu1—O1i | 1.9181 (11) | C6—C7 | 1.503 (2) |
| Cu1—O4i | 1.9366 (12) | C2—H2 | 0.9499 |
| Cu1—O5i | 2.4462 (16) | C7—H7A | 0.9793 |
| O1—C1 | 1.2707 (19) | C7—H7B | 0.9802 |
| O2—C3 | 1.362 (2) | C7—H7C | 0.9796 |
| O2—C4 | 1.399 (2) | C8—H8A | 0.9805 |
| O3—C4 | 1.208 (2) | C8—H8B | 0.9800 |
| O4—C6 | 1.257 (2) | C8—H8C | 0.9800 |
| O5—C9 | 1.224 (2) | C9—H9 | 0.9501 |
| N1—C9 | 1.324 (2) | C10—H10A | 0.9804 |
| N1—C10 | 1.447 (3) | C10—H10B | 0.9795 |
| N1—C11 | 1.451 (3) | C10—H10C | 0.9804 |
| C1—C2 | 1.439 (2) | C11—H11A | 0.9808 |
| C1—C5 | 1.434 (2) | C11—H11B | 0.9800 |
| C2—C3 | 1.333 (2) | C11—H11C | 0.9800 |
| Cu1···H11Bii | 3.5934 | C11···O4xi | 3.380 (3) |
| Cu1···H11Biii | 3.5934 | C4···H7C | 2.8540 |
| O1···O4 | 2.7325 (17) | C4···H7B | 2.9629 |
| O1···O5 | 3.040 (2) | C6···H8Cix | 2.8916 |
| O1···C6 | 2.926 (2) | C8···H11Cxii | 3.0797 |
| O1···C7iv | 3.390 (2) | C9···H8Cx | 2.9937 |
| O1···C9i | 3.279 (2) | H2···O3iv | 2.8573 |
| O1···O4i | 2.7189 (17) | H2···H7Biv | 2.4278 |
| O1···O5i | 3.175 (2) | H2···H8B | 2.4503 |
| O2···C10v | 3.367 (3) | H7A···H11Aii | 2.5766 |
| O2···C9v | 3.338 (2) | H7A···H9xiii | 2.4515 |
| O3···C7 | 2.753 (3) | H7B···O1vii | 2.9016 |
| O4···O1i | 2.7189 (17) | H7B···O3 | 2.5247 |
| O4···O1 | 2.7325 (17) | H7B···C4 | 2.9629 |
| O4···O5i | 3.190 (2) | H7B···H2vii | 2.4278 |
| O4···O5 | 3.049 (2) | H7C···O3 | 2.4969 |
| O4···C1 | 2.880 (2) | H7C···C4 | 2.8540 |
| O4···C11ii | 3.380 (3) | H7C···O3viii | 2.7275 |
| O5···O4i | 3.190 (2) | H8B···H2 | 2.4503 |
| O5···C1 | 3.381 (2) | H8B···H10Cxiv | 2.5316 |
| O5···O4 | 3.049 (2) | H8C···C9v | 2.9937 |
| O5···O1 | 3.040 (2) | H8C···O4ix | 2.8797 |
| O5···O1i | 3.175 (2) | H8C···C6ix | 2.8916 |
| O1···H11Biii | 2.8143 | H8C···H11Cxii | 2.5529 |
| O1···H9i | 2.6870 | H9···H10C | 2.2342 |
| O1···H7Biv | 2.9016 | H9···O1i | 2.6870 |
| O3···H10Avi | 2.7234 | H9···H7Axiii | 2.4515 |
| O3···H7B | 2.5247 | H10A···H11B | 2.5639 |
| O3···H2vii | 2.8573 | H10A···O3vi | 2.7234 |
| O3···H7Cviii | 2.7275 | H10B···H11A | 2.5468 |
| O3···H10Cv | 2.6667 | H10C···O3x | 2.6667 |
| O3···H7C | 2.4969 | H10C···H8Bxv | 2.5316 |
| O4···H8Cix | 2.8797 | H10C···H9 | 2.2342 |
| O5···H11C | 2.3680 | H11A···H7Axi | 2.5766 |
| C2···C4ix | 3.577 (2) | H11A···H10B | 2.5468 |
| C4···C2ix | 3.577 (2) | H11B···Cu1xi | 3.5934 |
| C6···C8ix | 3.568 (3) | H11B···H10A | 2.5639 |
| C7···O3 | 2.753 (3) | H11B···Cu1iii | 3.5934 |
| C7···O1vii | 3.390 (2) | H11B···O1iii | 2.8143 |
| C8···C6ix | 3.568 (3) | H11C···O5 | 2.3680 |
| C9···O2x | 3.338 (2) | H11C···C8xii | 3.0797 |
| C10···O2x | 3.367 (3) | H11C···H8Cxii | 2.5529 |
| O1—Cu1—O4 | 90.29 (5) | C4—C5—C6 | 119.53 (14) |
| O1—Cu1—O5 | 87.44 (6) | O4—C6—C5 | 123.26 (14) |
| O1—Cu1—O1i | 180.00 | O4—C6—C7 | 114.21 (15) |
| O1—Cu1—O4i | 89.71 (5) | C5—C6—C7 | 122.52 (15) |
| O1—Cu1—O5i | 92.56 (6) | O5—C9—N1 | 125.16 (17) |
| O4—Cu1—O5 | 87.33 (5) | C1—C2—H2 | 119.38 |
| O1i—Cu1—O4 | 89.71 (5) | C3—C2—H2 | 119.39 |
| O4—Cu1—O4i | 180.00 | C6—C7—H7A | 109.52 |
| O4—Cu1—O5i | 92.67 (5) | C6—C7—H7B | 109.45 |
| O1i—Cu1—O5 | 92.56 (6) | C6—C7—H7C | 109.46 |
| O4i—Cu1—O5 | 92.67 (5) | H7A—C7—H7B | 109.47 |
| O5—Cu1—O5i | 180.00 | H7A—C7—H7C | 109.50 |
| O1i—Cu1—O4i | 90.29 (5) | H7B—C7—H7C | 109.42 |
| O1i—Cu1—O5i | 87.44 (6) | C3—C8—H8A | 109.43 |
| O4i—Cu1—O5i | 87.33 (5) | C3—C8—H8B | 109.48 |
| Cu1—O1—C1 | 126.09 (11) | C3—C8—H8C | 109.46 |
| C3—O2—C4 | 122.47 (13) | H8A—C8—H8B | 109.47 |
| Cu1—O4—C6 | 128.72 (11) | H8A—C8—H8C | 109.43 |
| Cu1—O5—C9 | 120.37 (13) | H8B—C8—H8C | 109.55 |
| C9—N1—C10 | 121.90 (17) | O5—C9—H9 | 117.39 |
| C9—N1—C11 | 120.71 (18) | N1—C9—H9 | 117.45 |
| C10—N1—C11 | 117.35 (18) | N1—C10—H10A | 109.46 |
| O1—C1—C2 | 116.55 (14) | N1—C10—H10B | 109.52 |
| O1—C1—C5 | 125.50 (14) | N1—C10—H10C | 109.50 |
| C2—C1—C5 | 117.94 (14) | H10A—C10—H10B | 109.46 |
| C1—C2—C3 | 121.23 (15) | H10A—C10—H10C | 109.40 |
| O2—C3—C2 | 121.52 (15) | H10B—C10—H10C | 109.48 |
| O2—C3—C8 | 111.62 (15) | N1—C11—H11A | 109.47 |
| C2—C3—C8 | 126.86 (16) | N1—C11—H11B | 109.47 |
| O2—C4—O3 | 113.66 (15) | N1—C11—H11C | 109.50 |
| O2—C4—C5 | 117.70 (14) | H11A—C11—H11B | 109.48 |
| O3—C4—C5 | 128.63 (16) | H11A—C11—H11C | 109.43 |
| C1—C5—C4 | 119.01 (14) | H11B—C11—H11C | 109.47 |
| C1—C5—C6 | 121.40 (14) | ||
| O4—Cu1—O1—C1 | −22.49 (15) | C2—C1—C5—C6 | −174.68 (16) |
| O4xvi—Cu1—O1—C1 | 157.51 (15) | O1—C1—C5—C4 | −178.35 (16) |
| O1—Cu1—O4—C6 | 19.61 (16) | C2—C1—C5—C4 | 2.3 (2) |
| O1xvi—Cu1—O4—C6 | −160.39 (16) | O3—C4—C5—C6 | −3.7 (3) |
| Cu1—O1—C1—C5 | 15.0 (2) | O2—C4—C5—C6 | 177.92 (15) |
| Cu1—O1—C1—C2 | −165.66 (12) | O3—C4—C5—C1 | 179.2 (2) |
| O1—C1—C2—C3 | 176.54 (17) | O2—C4—C5—C1 | 0.8 (2) |
| C5—C1—C2—C3 | −4.1 (3) | Cu1—O4—C6—C5 | −8.1 (3) |
| C1—C2—C3—O2 | 2.5 (3) | Cu1—O4—C6—C7 | 172.88 (13) |
| C1—C2—C3—C8 | −177.56 (19) | C1—C5—C6—O4 | −8.3 (3) |
| C4—O2—C3—C2 | 1.0 (3) | C4—C5—C6—O4 | 174.68 (16) |
| C4—O2—C3—C8 | −178.96 (18) | C1—C5—C6—C7 | 170.61 (18) |
| C3—O2—C4—O3 | 178.73 (17) | C4—C5—C6—C7 | −6.4 (3) |
| C3—O2—C4—C5 | −2.6 (3) | C10—N1—C9—O5 | 179.3 (2) |
| O1—C1—C5—C6 | 4.6 (3) | C11—N1—C9—O5 | 1.8 (3) |
| Symmetry codes: (i) −x, −y, −z; (ii) x, y+1, z; (iii) −x, −y−1, −z; (iv) x−1, y, z; (v) x, y, z+1; (vi) −x+1, −y−1, −z; (vii) x+1, y, z; (viii) −x+1, −y, −z+1; (ix) −x, −y, −z+1; (x) x, y, z−1; (xi) x, y−1, z; (xii) −x, −y−1, −z+1; (xiii) −x+1, −y, −z; (xiv) x−1, y, z+1; (xv) x+1, y, z−1; (xvi) −x, −y, −z. |
| Cu1—O1 | 1.9181 (11) | Cu1—O5 | 2.4462 (16) |
| Cu1—O4 | 1.9366 (12) | ||
| O1—Cu1—O4 | 90.29 (5) | O4—Cu1—O5 | 87.33 (5) |
| O1—Cu1—O5 | 87.44 (6) |
The authors thank Dr Chahrazed Beghidja for help during crystal selection and X-ray diffraction data collection.
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Dehydroacetic acid DHA, [3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione], (Arndt et al., 1936) is an industrial product used as a fungicide, bactericide and also as an important intermediate in organic synthesis. However, little is known on its metal complexes; those with Cu and Zn have been reported to be, respectively, a fungicide and a heat stabilizer for vinyl chloride resins. There are some other reports in the patent literature and also the stability constantes of some complexes have been measured. (Casabó et al., 1987). The Cu complex has been already described in this latter report, but the characterization of the compound was based only on thermal and elemental analysis, and on IR and NMR spectroscopy.
As an extension of our work (Djedouani et al., 2006), we present here the synthesis and crystal structure determination of [Cu(DHA)2(DMF)2] (I), which molecular structure is illustrated in Fig. 1.
The CuII center, lying on an inversion center, is coordinated to six oxygen atoms forming an elongated octahedra. The equatorial plane is defined by two DHA ligands, each chelating the metal through two oxygen atoms, O2 and O3, while the two dimethylformamide molecules fill the two axial sites via their oxygen atom (O1), in a similar fashion to that observed in other DHA complexes (Zucolotto et al., 2002) but with a larger distortion due to the Jahn-Teller effect. This can be envisaged when comparing with the Co isostructural isolog Co(DHA)2(DMF)2 (A. Gelasco, et al., 1997; Casabó et al., 1987): the Cu—O(DMF) bond length in (I), (2.446 (16) Å) is significantly longer than the corresponding Co—O(DMF) distance, 2.168 (2) Å, while the equatorial bonds are slightly shorter. The coordination distances in (I) are in good agreement with those found in Cu(DHA)2(DMSO)2 (DMSO: dimethylsulfoxyde, Djedouani et al., 2006).
The structure of (I) is different from the Mn(DHA)2(H2O)2 one, in which one water molecule is at the axial position and the other at the equatorial position.
The dimethylformamide molecules are involved in intermolecular hydrogen bonding via weak C—H···O interactions. (Figure 2),