metal-organic compounds
trans-Bis(acetato-κO)bis(2-aminoethanol-κ2N,O)nickel(II)
aTechnische Universität Darmstadt, Fachbereich Material- und Geowissenschaften, Petersenstrasse 23, D-64287 Darmstadt, Germany
*Correspondence e-mail: mseifba@materials.tu-darmstadt.de
In the title compound, [Ni(CH3CO2)2(C2H7NO)2], the NiII cation, located on an inversion center, is N,O-chelated by two 2-aminoethanol molecules and further coordinated by two monodendate acetate anions in a slightly distorted octahedral geometry. The latter is stabilized by intramolecular O—H⋯O hydrogen bonds involving the non-coordinated O atom of the acetate and the H atom of the hydroxy group of the 2-aminoethanol ligand. In the crystal, N—H⋯O hydrogen bonds link the molecules into a three-dimensional supramolecular framework that involves (a) the coordinated acetate O atom and one of the H atoms of the amino group and (b) the non-coordinated acetate O atom and the other H atom of the amino group.
Related literature
For an application of the title compound, see: Bazarjani et al. (2011). For the synthesis of NiO via the sol-gel route, see: Ozer & Lampert (1998); Livage & Ganguli (2001). For supramolecular structures of transition metal complexes, see: Desiraju (1995, 2007). For related structures, see: Downie et al. (1971); Werner et al. (1996); Williams et al. (2001).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536812014237/zl2465sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812014237/zl2465Isup2.hkl
Synthesis of title compound. 5.76 g of nickel (II) acetate tetrahydrate (>=99.0%, Sigma Aldrich) was added to 150 cm3 absolute ethanol (>=98, Sigma Aldrich) and mixed with 4.24 g of ethanolamine (>=99.0%, Sigma Aldrich) in a molar ratio of 1:3. The resultant bluish solution was stirred in air for 24 h, paper filtered to remove any insoluble compounds and used for the crystallization of single crystals based on the following procedure: one third of the latter bluish clear solution was removed via distillation under vacuum at room temperature. The solution was kept at 5 °C for two weeks to grow the single crystals.
The H atoms of the NH group and OH group were located in a difference map and later restrained to the distance N—H = 0.86 (2) Å and O—H = 0.82 (2) Å. The other H atoms were positioned with idealized geometry using a riding model with C—H = 0.93–0.97 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).
Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell
CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: publCIF (Westrip, 2010).[Ni(C2H3O2)2(C2H7NO)2] | F(000) = 316 |
Mr = 298.97 | Dx = 1.544 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1155 reflections |
a = 5.3284 (5) Å | θ = 2.7–28.0° |
b = 9.216 (1) Å | µ = 1.53 mm−1 |
c = 13.133 (2) Å | T = 293 K |
β = 94.22 (1)° | Rod, light blue |
V = 643.17 (13) Å3 | 0.16 × 0.08 × 0.06 mm |
Z = 2 |
Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector | 1314 independent reflections |
Radiation source: fine-focus sealed tube | 1035 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
Rotation method data acquisition using ω and ϕ scans | θmax = 26.4°, θmin = 3.1° |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009) | h = −4→6 |
Tmin = 0.792, Tmax = 0.914 | k = −11→6 |
2309 measured reflections | l = −16→11 |
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) = 0.093 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0555P)2 + 0.1361P] where P = (Fo2 + 2Fc2)/3 |
1314 reflections | (Δ/σ)max < 0.001 |
89 parameters | Δρmax = 0.32 e Å−3 |
3 restraints | Δρmin = −0.25 e Å−3 |
[Ni(C2H3O2)2(C2H7NO)2] | V = 643.17 (13) Å3 |
Mr = 298.97 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 5.3284 (5) Å | µ = 1.53 mm−1 |
b = 9.216 (1) Å | T = 293 K |
c = 13.133 (2) Å | 0.16 × 0.08 × 0.06 mm |
β = 94.22 (1)° |
Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector | 1314 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009) | 1035 reflections with I > 2σ(I) |
Tmin = 0.792, Tmax = 0.914 | Rint = 0.022 |
2309 measured reflections |
R[F2 > 2σ(F2)] = 0.036 | 3 restraints |
wR(F2) = 0.093 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | Δρmax = 0.32 e Å−3 |
1314 reflections | Δρmin = −0.25 e Å−3 |
89 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 | ||
C1 | −0.0425 (6) | 0.1901 (3) | 0.0329 (3) | 0.0405 (7) | |
H1A | −0.1460 | 0.1586 | −0.0269 | 0.049* | |
H1B | −0.0414 | 0.1133 | 0.0834 | 0.049* | |
C2 | −0.2241 (5) | 0.7831 (3) | −0.0038 (2) | 0.0373 (7) | |
H2A | −0.2846 | 0.8673 | 0.0314 | 0.045* | |
H2B | −0.3346 | 0.7669 | −0.0648 | 0.045* | |
C3 | 0.2827 (5) | 0.4706 (3) | 0.2084 (2) | 0.0344 (7) | |
C4 | 0.5055 (6) | 0.5114 (5) | 0.2804 (2) | 0.0572 (10) | |
H4A | 0.5577 | 0.6085 | 0.2658 | 0.069* | |
H4B | 0.6417 | 0.4455 | 0.2717 | 0.069* | |
H4C | 0.4587 | 0.5064 | 0.3495 | 0.069* | |
N1 | −0.2255 (4) | 0.6560 (3) | 0.06274 (18) | 0.0304 (5) | |
H11N | −0.373 (4) | 0.624 (3) | 0.069 (2) | 0.036* | |
H12N | −0.161 (5) | 0.681 (3) | 0.1224 (16) | 0.036* | |
O1 | −0.1486 (4) | 0.3187 (2) | 0.07349 (15) | 0.0315 (5) | |
H1O | −0.077 (5) | 0.328 (4) | 0.1293 (16) | 0.038* | |
O2 | 0.2717 (3) | 0.5287 (2) | 0.12075 (15) | 0.0331 (5) | |
O3 | 0.1255 (4) | 0.3817 (3) | 0.23830 (16) | 0.0475 (6) | |
Ni1 | 0.0000 | 0.5000 | 0.0000 | 0.02502 (18) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0472 (17) | 0.0281 (15) | 0.0470 (17) | −0.0085 (13) | 0.0089 (14) | 0.0003 (13) |
C2 | 0.0388 (16) | 0.0297 (15) | 0.0437 (17) | 0.0039 (13) | 0.0053 (13) | −0.0015 (14) |
C3 | 0.0283 (13) | 0.0462 (19) | 0.0286 (15) | 0.0031 (12) | 0.0011 (11) | −0.0047 (12) |
C4 | 0.0442 (18) | 0.098 (3) | 0.0287 (15) | −0.016 (2) | −0.0052 (14) | 0.0002 (19) |
N1 | 0.0269 (11) | 0.0343 (13) | 0.0303 (13) | −0.0046 (10) | 0.0048 (10) | 0.0000 (11) |
O1 | 0.0288 (10) | 0.0335 (11) | 0.0325 (11) | −0.0061 (9) | 0.0037 (8) | 0.0012 (9) |
O2 | 0.0282 (9) | 0.0412 (12) | 0.0292 (10) | −0.0055 (8) | −0.0024 (8) | 0.0035 (8) |
O3 | 0.0456 (12) | 0.0659 (15) | 0.0308 (11) | −0.0150 (12) | 0.0010 (9) | 0.0109 (11) |
Ni1 | 0.0218 (2) | 0.0271 (3) | 0.0259 (3) | −0.0032 (2) | 0.00023 (17) | 0.0028 (2) |
C1—O1 | 1.432 (4) | C4—H4B | 0.9600 |
C1—C2i | 1.518 (4) | C4—H4C | 0.9600 |
C1—H1A | 0.9700 | N1—Ni1 | 2.082 (2) |
C1—H1B | 0.9700 | N1—H11N | 0.849 (17) |
C2—N1 | 1.462 (4) | N1—H12N | 0.863 (17) |
C2—C1i | 1.518 (4) | O1—Ni1 | 2.1129 (19) |
C2—H2A | 0.9700 | O1—H1O | 0.805 (17) |
C2—H2B | 0.9700 | O2—Ni1 | 2.0841 (19) |
C3—O3 | 1.255 (3) | Ni1—N1i | 2.082 (2) |
C3—O2 | 1.267 (4) | Ni1—O2i | 2.0841 (19) |
C3—C4 | 1.510 (4) | Ni1—O1i | 2.1129 (19) |
C4—H4A | 0.9600 | ||
O1—C1—C2i | 111.2 (2) | Ni1—N1—H11N | 111 (2) |
O1—C1—H1A | 109.4 | C2—N1—H12N | 108 (2) |
C2i—C1—H1A | 109.4 | Ni1—N1—H12N | 110 (2) |
O1—C1—H1B | 109.4 | H11N—N1—H12N | 108 (3) |
C2i—C1—H1B | 109.4 | C1—O1—Ni1 | 108.21 (16) |
H1A—C1—H1B | 108.0 | C1—O1—H1O | 105 (2) |
N1—C2—C1i | 109.1 (2) | Ni1—O1—H1O | 100 (2) |
N1—C2—H2A | 109.9 | C3—O2—Ni1 | 128.35 (18) |
C1i—C2—H2A | 109.9 | N1—Ni1—N1i | 180.0 |
N1—C2—H2B | 109.9 | N1—Ni1—O2i | 90.00 (9) |
C1i—C2—H2B | 109.9 | N1i—Ni1—O2i | 90.00 (9) |
H2A—C2—H2B | 108.3 | N1—Ni1—O2 | 90.00 (9) |
O3—C3—O2 | 125.0 (3) | N1i—Ni1—O2 | 90.00 (9) |
O3—C3—C4 | 118.6 (3) | O2i—Ni1—O2 | 180.00 (8) |
O2—C3—C4 | 116.4 (3) | N1—Ni1—O1i | 83.18 (9) |
C3—C4—H4A | 109.5 | N1i—Ni1—O1i | 96.82 (9) |
C3—C4—H4B | 109.5 | O2i—Ni1—O1i | 90.90 (7) |
H4A—C4—H4B | 109.5 | O2—Ni1—O1i | 89.10 (8) |
C3—C4—H4C | 109.5 | N1—Ni1—O1 | 96.82 (9) |
H4A—C4—H4C | 109.5 | N1i—Ni1—O1 | 83.18 (9) |
H4B—C4—H4C | 109.5 | O2i—Ni1—O1 | 89.10 (8) |
C2—N1—Ni1 | 106.76 (16) | O2—Ni1—O1 | 90.90 (7) |
C2—N1—H11N | 113 (2) | O1i—Ni1—O1 | 180.00 (9) |
C1i—C2—N1—Ni1 | −43.2 (3) | C3—O2—Ni1—N1 | 84.3 (2) |
C2i—C1—O1—Ni1 | 32.6 (3) | C3—O2—Ni1—N1i | −95.7 (2) |
O3—C3—O2—Ni1 | 0.3 (4) | C3—O2—Ni1—O1i | 167.5 (2) |
C4—C3—O2—Ni1 | 179.4 (2) | C3—O2—Ni1—O1 | −12.5 (2) |
C2—N1—Ni1—O2i | −70.53 (18) | C1—O1—Ni1—N1 | 173.11 (17) |
C2—N1—Ni1—O2 | 109.47 (18) | C1—O1—Ni1—N1i | −6.89 (17) |
C2—N1—Ni1—O1i | 20.37 (17) | C1—O1—Ni1—O2i | 83.22 (17) |
C2—N1—Ni1—O1 | −159.63 (17) | C1—O1—Ni1—O2 | −96.78 (17) |
Symmetry code: (i) −x, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11N···O2ii | 0.85 (2) | 2.24 (2) | 3.071 (3) | 168 (3) |
N1—H12N···O3iii | 0.86 (2) | 2.60 (2) | 3.352 (3) | 146 (3) |
O1—H1O···O3 | 0.81 (2) | 1.80 (2) | 2.587 (3) | 166 (3) |
Symmetry codes: (ii) x−1, y, z; (iii) −x, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [Ni(C2H3O2)2(C2H7NO)2] |
Mr | 298.97 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 5.3284 (5), 9.216 (1), 13.133 (2) |
β (°) | 94.22 (1) |
V (Å3) | 643.17 (13) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.53 |
Crystal size (mm) | 0.16 × 0.08 × 0.06 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2009) |
Tmin, Tmax | 0.792, 0.914 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2309, 1314, 1035 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.625 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.093, 1.03 |
No. of reflections | 1314 |
No. of parameters | 89 |
No. of restraints | 3 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.32, −0.25 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009), publCIF (Westrip, 2010).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H11N···O2i | 0.849 (17) | 2.236 (18) | 3.071 (3) | 168 (3) |
N1—H12N···O3ii | 0.863 (17) | 2.60 (2) | 3.352 (3) | 146 (3) |
O1—H1O···O3 | 0.805 (17) | 1.799 (19) | 2.587 (3) | 166 (3) |
Symmetry codes: (i) x−1, y, z; (ii) −x, y+1/2, −z+1/2. |
Complex | C—Oa | C—Ob | C—C | A | B | C | Reference |
[Ni(CH3CO2)2(C2H7NO)2] | 1.255 (3) | 1.267 (4) | 1.510 (4) | 125.0 (3) | 118.6 (3) | 116.4 (3) | This work |
[Ni(CH3CO2)2(C4H11NO)2] | 1.260 (4), 1.249 (4) | 1.263 (4) | 1.498 (5), 1.504 (5) | 124.6 (3), 125.7 (3) | 118.0 (3), 117.7 (3) | 117.4 (3), 116.6 (3) | Williams et al. (2001) |
[Ni(CH3CO2)2(H2O)4] | 1.255 (5) | 1.272 (5) | 1.503 (3) | 122.5 | 119.5 | 117.9 | Downie et al. (1971) |
[Ni(CH3CO2)2(C6H7N3O)2(EtOH)2] | 1.255 (4) | 1.265 (4) | 1.511 (5) | 124.7 (3) | 117.3 (3) | 117.9 (3) | Werner et al. (1996) |
Complex | Ni—O(acetate) | Reference |
[Ni(CH3CO2)2(C2H7NO)2] | 2.0841 (19) | This work |
[Ni(CH3CO2)2(C4H11NO)2] | 2.050 (2), 2.043 (2) | Williams et al. (2001) |
[Ni(CH3CO2)2(H2O)4] | 2.067 (3) | Downie et al. (1971) |
[Ni(CH3CO2)2(C6H7N3O)2(EtOH)2] | 2.118 (2) | Werner et al. (1996) |
Complex | Ni—O(non-acetate ligand) | Reference |
[Ni(CH3CO2)2(C2H7NO)2] | Ni—O (C2H7NO) 2.1129 (19) | This work |
[Ni(CH3CO2)2(C4H11NO)2] | Ni—O (C4H11NO) 2.111 (2), 2.109 (2) | Williams et al. (2001) |
[Ni(CH3CO2)2(H2O)4] | Ni—O (H2O) 2.048 (4) | Downie et al. (1971) |
[Ni(C5H8O2)2(C4H11NO)] | Ni—O (C5H8O2) 2.026 (3), 2.013 (4), 2.024 (4), 2.2045 (3); Ni—O (C4H11NO) 2.111 (4) | Williams et al. (2001) |
Complex | Ni—N (Å) | Reference |
[Ni(CH3CO2)2(C2H7NO)2] | Ni—N 2.082 (2) | This work |
[Ni(CH3CO2)2(C4H11NO)2] | Ni—N 2.142 (3), 2.145 (3) | Williams et al. (2001) |
[Ni(C5H8O2)2(C4H11NO)] | Ni—N 2.169 (4) | Williams et al. (2001) |
[Ni(CH3CO2)2(C6H7N3O)2(EtOH)2] | Ni—N 2.054 (3), 2.116 (3) | Werner et al. (1996) |
Acknowledgements
This work was performed within the framework of the project "Thermoresistant Ceramic Membranes with Integrated Gas Sensor for High Temperature Separation and Detection of Hydrogen and Carbon Monoxide" as part of the DFG Priority Programme "Adapting Surfaces for High Temperature Applications" (DFG-SPP 1299, www.spp-haut.de, DFG – German Research Foundation).
References
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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.
The synthesis of the title compound is performed at room temperature under ambient conditions by substituting H2O of [Ni(CH3CO2)2(H2O)4] with 2-aminoethanol. As the title compound is water-free, stable under ambient conditions and well soluble in lower alcohols, it represents a cost effective precursor for the sol-gel synthesis of NiO-based nanostrutures. The latter are of interest for switchable automobile mirrors and smart windows (Ozer & Lampert, 1998). Another application of the title compound is the synthesis of nanocomposite materials; nickel-polysilazane materials with ultrasmall and well dispersed nickel nanoparticles were obtained at room temperature in the reaction between the title compound and a polysilazane (Bazarjani et al., 2011). The title compound possesses significantly higher stability and higher solubility in lower alcohols when compared with a similar NiII complex coordinated by two N,N-dimethylaminoethanol molecules, [Ni(CH3CO2)2(C4H11NO)2], which is air-sensitive (Williams et al., 2001). These differences are due to the –NH2 group of the 2-aminoethanol ligand which is in the solid state hydrogen bonded to neighbouring [Ni(CH3CO2)2(C2H7NO)2] units and in solution it can get involved in hydrogen bonding with lower alcohols. The former results in the increased stability of the title compound, the latter is responsible for higher solubility of the title compound in alcohols (e.g. for methanol, compare 0.18 mol l-1 for the title compund to 0.10 mol l-1 for [Ni(CH3CO2)2(C4H11NO)2] at 25 °C).
Figure 1 shows a perspective view of the NiII coordination in the title compound; the atom numbering scheme, the interatomic distances and angles are also indicated. The distortion from octahedral symmetry is due to the slight deviation of the internal bite angle of the 2-aminoethanol ligands from 90°, i.e. 83.16 (9)° for N1—Ni1—O1i, which is similar to that observed in [Ni(CH3CO2)2(C4H11NO)2] (Williams et al., 2001). The title compound is stabilized through inter- and intramolecular O—H···O and N—H···O hydrogen bonds similar to those of other supramolecular crystals of transition metal complexes (Desiraju, 1995, 2007) (Figure 2, Table 1).
The geometry and coordination of the monodentate acetate group in the title compound is comparable to those in [Ni(CH3CO2)2(H2O)4] (Downie et al., 1971), in [Ni(CH3CO2)2(C6H7N3O)2(EtOH)2] (Werner et al., 1996), and in [Ni(CH3CO2)2(C4H11NO)2] (Williams et al., 2001). The acetate groups are close to be fully ionized (CH3CO2-); as in a fully ionized acetate, the C–C–O angles (B and C in Figure 3) are about 115.7° and the O–C–O angle is about 126° (A in Figure 3, Table 2) (Williams et al., 2001). The length of the Ni—O(acetate) (Table 3), Ni—O(non-acetate) (Table 4) and Ni—N bonds (Table 5) in the title compound are comparable to those in similar NiII complexes, i.e. in [Ni(CH3CO2)2(C4H11NO)2] (Williams et al., 2001), [Ni(CH3CO2)2(H2O)4] (Downie et al., 1971) and [Ni(CH3CO2)2(C6H7N3O)2(EtOH)2] (Werner et al., 1996).