research communications
N,N′,N′′ versus N,N′,O imine-containing coordination motifs: ligand-directed synthesis of mononuclear and binuclear CuII compounds
aInstitute of Chemistry, University of Campinas - UNICAMP, Campinas – SP 13083-970, Brazil
*Correspondence e-mail: raphael.enoque@gmail.com
It is demonstrated here that tridentate imine ligands can control the nuclearity of copper(II) complexes based on the donor atoms present in the ligand. The N,N′,N′′-donating imine ligand led to a mononuclear compound, namely dichlorido[N,N-dimethyl-N′-(pyridin-2-ylmethylidene)ethane-1,2-diamine]copper(II) monohydrate, [CuCl2(C10H15N3)]·H2O, 1, while the N,N′,O-donating imine ligand produced a binuclear metal complex, namely μ2-chlorido-dichlorido(μ2-2-{[2-(dimethylamino)ethyl]iminomethyl}phenolato)(N,N-dimethylethylenediamine)dicopper(II) 0.11-hydrate, [Cu2(C11H15N2O)Cl3(C4H12N2)]·0.11H2O, 2. The structure of 2 is a remarkable example of a binuclear copper(II) complex containing a single substituted 2-iminomethylphenolate ligand that has two copper(II) sites in square-pyramidal coordination.
1. Chemical context
Copper(II) complexes with imine ligands have attracted much attention in the past few decades due to a variety of possible applications, including catalysis [aerobic oxidation of et al., 2006; Alaji et al., 2014), olefin epoxidation (Das et al., 1997) and ring-opening reactions (John et al., 2007)], and also in medicinal chemistry for both antibacterial (Ali et al., 2015) and antitumour applications (Creaven et al., 2010; Pervez et al., 2016).
(NairnNonmacrocyclic binuclear copper compounds are of interest because they can serve as models for metalloproteins and metalloenzymes, as well as representing interesting subjects for studying molecular magnetism. Strong magnetic exchange is present in the two copper(II) sites of haemocyanin (Chen & Solomon, 2004), which represents a challenge that must be considered when synthetic models are developed. One strategy, introduced by Robson (1970), makes use of symmetrical imino ligands containing a phenolate bridge to keep the CuII atoms close in space. represent an interesting class of ligands because they can be easily synthesized and fine-tuned to the desired application by introducing extra donor atoms or groups with the desired steric properties into the side chains. A limited number of binuclear copper(II) compounds containing substituted 2-iminomethylphenole ligands have been reported in the literature (Gao et al., 2011; Tang et al., 2008). This kind of structure, where the polydentate ligand has fewer donor atoms than the of the metal centre, is of interest for the design of more flexible binuclear model compounds.
We describe here the crystal structures of mononuclear (1) and binuclear (2) copper(II) complexes with tridentate imine-containing ligands obtained by a one-pot synthetic method. The nuclearity of the complexes was shown to be directed by the different donor atoms present in the imine ligand.
2. Structural commentary
The mononuclear compound 1 has the central CuII cation in a square-pyramidal coordination environment (Fig. 1a). The CuII cation is displaced from the least-squares plane defined by the four coordinating atoms of the square base (N1, N2, N3 and Cl2) by 0.334 Å. The bond lengths to these atoms are: Cu—N1 = 2.060 (2), Cu—N2 = 1.978 (2), Cu—N3 = 2.058 (2) and Cu—Cl2 = 2.2639 (8) Å; the Cu—Cl bond length to the apical Cl1 atom that completes the first coordination sphere is considerably longer, at 2.5013 (8) Å. In order to assess the coordination geometry of copper(II) more quantitatively, the τ5 index as defined by Addison et al. (1984) can be used. A perfect square-pyramidal coordination geometry is defined by τ5 = 0.0, while it is 1.0 for a perfect trigonal–bipyramidal coordination geometry. For compound 1, τ5 is 0.059, indicating an almost perfect square-pyramidal coordination geometry.
The binuclear compound 2 has two copper(II) cations, both in a square-pyramidal coordination environment (Fig. 2a). The presence of the phenolate group in the structure of the imine ligand directs the reaction with copper(II) cations to form a binuclear coordination compound, in contrast with the mononuclear species 1 obtained when a pyridine group is present in the ligand. Atoms Cu1 and Cu2 in 2 are displaced from the least-squares plane defined by the four coordinating atoms of the square base (N1, N2, O1 and Cl2 for Cu1; N3, N4, O1 and Cl3 for Cu2) by 0.299 and 0.170 Å, respectively. The distances from the central copper(II) cations to these ligating atoms are: Cu1—N1 = 2.068 (2), Cu1—N2 = 1.959 (2), Cu1—O1 = 1.968 (1) and Cu1—Cl2 = 2.2958 (5) Å; Cu2—N3 = 2.021 (2), Cu2—N4 = 2.040 (2), Cu2—Cl3 = 2.2501 (5) and Cu2—O1 = 2.004 (1) Å. The two Cu—Cl distances to the apical Cl atoms are likewise longer, Cu1—Cl1 = 2.5476 (5) Å and Cu2—Cl2 = 2.5938 (5) Å. The Cu⋯Cu distance within the binuclear complex is 3.2525 (5) Å. In compound 2, the τ5 index for Cu1 is 0.294 and for Cu2 0.260, indicating more distorted square-pyramidal coordination environments for both central copper(II) cations.
After refining the structure of the binuclear compound 2, a solvent-accessible void of 42 Å3 was detected by a PLATON analysis (Spek, 2009). The highest residual electron-density peak fitted perfectly within this void. We have modelled the corresponding site as an O atom of a partially occupied water molecule, showing an occupancy of 0.11. Given the low occupancy, this water molecule is not represented in the molecular view nor in the crystal packing (Fig. 2).
3. Supramolecular features
The presence of a water molecule in the 1 leads to the formation of a hydrogen-bonded chain along [101] involving the apical ligand Cl1 (Fig. 1b and Table 1). In addition, a short contact between the C—H group of the imine group and the apical Cl1 ligand is observed (C5—H5⋯Cl1, Table 1). Finally, a similar C—H⋯Cl interaction between an aromatic H atom of the pyridine ring and the Cl2 ligand of the square base likewise contributes to the packing in the solid state (C9—H9⋯Cl2, Table 1). Besides these hydrogen bonds, an offset π–π stacking is observed between adjacent pyridine rings [centroid-to-centroid distance of 3.5709 (18) Å; symmetry code: −x, −y, −z].
of the mononuclear compoundIn terms of intermolecular contacts, a single set of hydrogen bonds is present in the 2, established between the non-substituted terminal amine group of N,N-dimethylethylenediamine and the apical chloride ligand Cl1 (Fig. 2b and Table 2). Similar to compound 1, a nonclassical hydrogen bond between an aromatic H atom of the phenolic ring and the Cl2 ligand also contributes to the intermolecular network (C8—H8⋯Cl2, Table 2). Differing from the structure of 1, a C—H⋯π interaction is observed for compound 2, with a C12—H12⋯centroid(phenyl) distance of 3.393 (2) Å (symmetry code: −x + 1, −y + 1, −z + 1). The partly occupied water molecule participates in a hydrogen bond with the μ2-bridging Cl2 ligand (Table 2).
of4. Database survey
The structures of the mononuclear and binuclear copper(II) compounds 1 and 2 were compared with analogues found in the Cambridge Structural Database (CSD; Groom et al., 2016), using the queries shown in Fig. 3. Only binuclear CuII compounds containing a single μ2-(monoiminomethyl)phenolate ligand were considered as analogues of 2. A total of 12 hits were found as analogues of 1, while 11 hits were found for analogues of 2, including both mono- and bis(iminomethyl)phenolate ligands. Averages of selected bond lengths (see representations in Fig. 3) were obtained using ConQuest (Version 1.19) and the statistical analysis module in Mercury (Version 3.9) (Macrae et al., 2008). The averaged values are collated in Table 3 and are in good agreement with the bond lengths in the structures of 1 and 2.
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The closest relation to 1 is associated with the nonhydrated analogue (CCDC entry TAWMEK; Yuan & Zhang, 2005), which has the CuII cation in a more distorted square-pyramidal coordination geometry than 1, with the following bond lengths: Cu—N1 = 2.275 (2), Cu—N2 = 2.104 (2) and Cu—N3 = 2.236 (2) Å, and almost identical Cu—Cl1 = 2.2573 (5) and Cu—Cl2 = 2.22561 (6) Å distances. The CuII cation is displaced from the mean plane defined by the four coordinating atoms of the square base by 0.622 Å. While for 1 τ5 = 0.0593, for the structure of TAWMEK τ5 = 0.302. The differences in the coordination environment of copper(II) probably arise as a consequence of the presence of the hydrogen-bonded network established between the chloride ligands and the water molecules in the of 1. The coordination spheres around the CuII cations in 1 and TAWMEK are compared in Fig. 4.
Regarding the binuclear compound 2, the search returned only two examples of binuclear CuII complexes containing a single μ2-(monoiminomethyl)phenolate ligand [VAMJIE (Gao et al., 2011) and UFATEB (Tang et al., 2008)]. The two structures have one CuII cation in a square-pyramidal environment, comprising the tridentate imine ligand, and one octahedrally surrounded CuII site, bridged by the phenolate and a chloride ligand. Structure 2, on the other hand, comprises a binuclear copper(II) complex with a single μ2-(monoiminomethyl)phenolate ligand that has two CuII coordination sites in square-pyramidal environments. The coordination spheres around the two CuII cations in 2 and UFATEB are compared in Fig. 4.
5. Synthesis and crystallization
Copper(II) chloride dihydrate was purchased from Vetec (Brazil). N,N-dimethylethylenediamine, pyridine-2-carboxaldehyde and salicylaldehyde were purchased from Sigma–Aldrich and used without further purification.
Compound 1, C10H15Cl2CuN3·H2O, was obtained as follows. In a 10 ml beaker, N,N-dimethylethylenediamine (0.10 mmol, 65.6 µl) was combined with pyridine-2-carboxaldehyde (0.10 mmol, 10 µl) in methanol (200 µl). The reaction was carried out at room temperature for 24 h. Afterwards, solid CuCl2·2H2O (0.10 mmol, 2.8 mg) was added to the reaction mixture. A polycrystalline green compound was obtained, filtered off and washed with small amounts of cold methanol. Elemental analysis was performed on a Perkin–Elmer CHNS-O 2400. Analysis, calculated for C10H15Cl2CuN3·H2O: C 36.4, H 5.2, N 12.7%; found: C 36.8, H 4.8, N 13.0%. The supernatant was transferred to an amber flask and green crystals suitable for single-crystal X-ray diffraction were obtained by slow evaporation.
Compound 2 (C15H27Cl3Cu2N4O·0.11H2O) was obtained following the same synthetic procedure as used for 1, but replacing pyridine-2-carboxaldehyde by salicylaldehyde (11 µl). Green needle-like crystals of 2 were obtained by slow evaporation of the supernatant. Since only a few crystals were obtained, no further analytical data were acquired.
6. details
Crystal data, data collection and structure . H atoms were placed in calculated positions, with C—H = 0.99 (CH2) or 0.95 Å (CH), with Uiso(H) = 1.2Ueq(C), and C—H = 0.98 Å (CH3) and Uiso(H) = 1.5Ueq(C). For structure 1, the H atoms of the water molecule were refined with an O—H distance restraint of 0.82 (1) Å and a H⋯H separation of 1.29 (2) Å, and with Uiso(H) = 1.5Ueq(O). For structure 2, the H atoms of the amine functionality (H3A and H3B) were refined freely. The occupancy of the partly occupied water solvent molecule was refined to a value of 0.11 (1); for this molecule, H atoms were not located and they were not considered in the final model.
details are summarized in Table 4
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Supporting information
https://doi.org/10.1107/S2056989017013652/wm5417sup1.cif
contains datablocks global, 2, 1. DOI:Structure factors: contains datablock 1. DOI: https://doi.org/10.1107/S2056989017013652/wm54171sup2.hkl
Structure factors: contains datablock 2. DOI: https://doi.org/10.1107/S2056989017013652/wm54172sup3.hkl
For both structures, data collection: APEX2 (Bruker, 2010); cell
SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: OLEX2 (Dolomanov et al., 2009), Mercury (Macrae et al., 2008); software used to prepare material for publication: publCIF (Westrip, 2010).[CuCl2(C10H15N3)]·H2O | F(000) = 676 |
Mr = 329.70 | Dx = 1.650 Mg m−3 |
Monoclinic, P21/n | Cu Kα radiation, λ = 1.54178 Å |
a = 6.9667 (5) Å | Cell parameters from 5700 reflections |
b = 24.735 (2) Å | θ = 6.0–68.2° |
c = 7.9294 (6) Å | µ = 5.93 mm−1 |
β = 103.693 (4)° | T = 150 K |
V = 1327.55 (18) Å3 | Needle, green |
Z = 4 | 0.27 × 0.05 × 0.05 mm |
Bruker APEX CCD area-detector diffractometer | 2199 reflections with I > 2σ(I) |
Detector resolution: 8.3333 pixels mm-1 | Rint = 0.041 |
φ and ω scans | θmax = 68.4°, θmin = 6.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2010) | h = −8→8 |
Tmin = 0.522, Tmax = 0.753 | k = −29→29 |
7065 measured reflections | l = −9→5 |
2361 independent reflections |
Refinement on F2 | 3 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.108 | w = 1/[σ2(Fo2) + (0.0521P)2 + 1.8713P] where P = (Fo2 + 2Fc2)/3 |
S = 1.10 | (Δ/σ)max < 0.001 |
2361 reflections | Δρmax = 0.65 e Å−3 |
162 parameters | Δρmin = −0.60 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Cu1 | 0.25867 (6) | 0.11867 (2) | 0.18700 (5) | 0.01663 (17) | |
Cl1 | 0.36674 (10) | 0.19272 (3) | 0.01545 (9) | 0.0226 (2) | |
Cl2 | 0.52625 (10) | 0.06383 (3) | 0.25165 (9) | 0.0239 (2) | |
N1 | 0.3071 (3) | 0.15604 (10) | 0.4256 (3) | 0.0196 (5) | |
N2 | −0.0116 (3) | 0.14595 (10) | 0.1726 (3) | 0.0195 (5) | |
N3 | 0.1025 (3) | 0.07572 (10) | −0.0233 (3) | 0.0173 (5) | |
C1 | −0.0402 (4) | 0.18436 (13) | 0.3060 (4) | 0.0244 (7) | |
H1A | −0.1083 | 0.1666 | 0.3874 | 0.029* | |
H1B | −0.1203 | 0.2156 | 0.2518 | 0.029* | |
C2 | 0.1668 (4) | 0.20274 (13) | 0.4012 (4) | 0.0237 (6) | |
H2A | 0.2132 | 0.2314 | 0.3333 | 0.028* | |
H2B | 0.1624 | 0.2180 | 0.5157 | 0.028* | |
C3 | 0.2592 (5) | 0.11624 (13) | 0.5493 (4) | 0.0259 (7) | |
H3A | 0.1234 | 0.1034 | 0.5060 | 0.039* | |
H3B | 0.2721 | 0.1334 | 0.6628 | 0.039* | |
H3C | 0.3506 | 0.0856 | 0.5609 | 0.039* | |
C4 | 0.5104 (5) | 0.17632 (14) | 0.4964 (4) | 0.0289 (7) | |
H4A | 0.6038 | 0.1461 | 0.5099 | 0.043* | |
H4B | 0.5184 | 0.1932 | 0.6096 | 0.043* | |
H4C | 0.5435 | 0.2030 | 0.4164 | 0.043* | |
C5 | −0.1490 (4) | 0.12990 (12) | 0.0464 (4) | 0.0204 (6) | |
H5 | −0.2802 | 0.1433 | 0.0270 | 0.024* | |
C6 | −0.0916 (4) | 0.08948 (12) | −0.0667 (4) | 0.0195 (6) | |
C7 | −0.2231 (5) | 0.06563 (13) | −0.2042 (4) | 0.0240 (7) | |
H7 | −0.3586 | 0.0756 | −0.2315 | 0.029* | |
C8 | −0.1550 (5) | 0.02693 (13) | −0.3020 (4) | 0.0260 (7) | |
H8 | −0.2428 | 0.0103 | −0.3979 | 0.031* | |
C9 | 0.0427 (5) | 0.01288 (13) | −0.2578 (4) | 0.0240 (6) | |
H9 | 0.0930 | −0.0136 | −0.3229 | 0.029* | |
C10 | 0.1664 (4) | 0.03815 (12) | −0.1165 (4) | 0.0205 (6) | |
H10 | 0.3018 | 0.0282 | −0.0854 | 0.025* | |
O1 | 0.9383 (4) | 0.19474 (11) | 0.7408 (4) | 0.0429 (7) | |
H1D | 0.919 (6) | 0.2249 (10) | 0.692 (6) | 0.064* | |
H1C | 1.055 (3) | 0.1978 (17) | 0.799 (6) | 0.064* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0140 (3) | 0.0238 (3) | 0.0107 (2) | 0.00267 (15) | 0.00034 (16) | 0.00037 (15) |
Cl1 | 0.0228 (4) | 0.0262 (4) | 0.0186 (3) | −0.0009 (3) | 0.0046 (3) | 0.0041 (3) |
Cl2 | 0.0182 (4) | 0.0300 (4) | 0.0210 (4) | 0.0068 (3) | −0.0004 (3) | 0.0012 (3) |
N1 | 0.0182 (12) | 0.0263 (13) | 0.0136 (11) | 0.0008 (10) | 0.0024 (9) | −0.0022 (10) |
N2 | 0.0182 (12) | 0.0255 (13) | 0.0154 (11) | 0.0031 (10) | 0.0054 (9) | 0.0010 (10) |
N3 | 0.0188 (12) | 0.0214 (12) | 0.0100 (10) | 0.0007 (9) | 0.0000 (9) | 0.0050 (9) |
C1 | 0.0235 (15) | 0.0312 (16) | 0.0195 (14) | 0.0038 (13) | 0.0068 (12) | −0.0030 (13) |
C2 | 0.0253 (16) | 0.0256 (16) | 0.0213 (14) | 0.0018 (12) | 0.0076 (12) | −0.0045 (12) |
C3 | 0.0311 (17) | 0.0342 (18) | 0.0115 (13) | 0.0011 (13) | 0.0030 (12) | 0.0014 (12) |
C4 | 0.0206 (15) | 0.0374 (18) | 0.0260 (16) | −0.0030 (13) | 0.0002 (12) | −0.0091 (14) |
C5 | 0.0158 (14) | 0.0247 (15) | 0.0202 (14) | 0.0013 (11) | 0.0033 (11) | 0.0063 (12) |
C6 | 0.0202 (14) | 0.0234 (15) | 0.0130 (12) | 0.0005 (11) | 0.0004 (11) | 0.0083 (11) |
C7 | 0.0208 (15) | 0.0310 (17) | 0.0163 (13) | −0.0011 (12) | −0.0035 (11) | 0.0077 (12) |
C8 | 0.0329 (17) | 0.0300 (17) | 0.0106 (13) | −0.0071 (13) | −0.0036 (12) | 0.0038 (12) |
C9 | 0.0328 (17) | 0.0266 (16) | 0.0123 (13) | −0.0011 (13) | 0.0046 (12) | 0.0018 (12) |
C10 | 0.0217 (14) | 0.0259 (15) | 0.0131 (13) | 0.0022 (12) | 0.0026 (11) | 0.0045 (11) |
O1 | 0.0434 (15) | 0.0465 (16) | 0.0357 (14) | 0.0004 (12) | 0.0028 (12) | 0.0057 (12) |
Cu1—Cl1 | 2.5013 (8) | C3—H3B | 0.9800 |
Cu1—Cl2 | 2.2639 (8) | C3—H3C | 0.9800 |
Cu1—N1 | 2.060 (2) | C4—H4A | 0.9800 |
Cu1—N2 | 1.978 (2) | C4—H4B | 0.9800 |
Cu1—N3 | 2.058 (2) | C4—H4C | 0.9800 |
N1—C2 | 1.496 (4) | C5—H5 | 0.9500 |
N1—C3 | 1.482 (4) | C5—C6 | 1.460 (4) |
N1—C4 | 1.482 (4) | C6—C7 | 1.380 (4) |
N2—C1 | 1.469 (4) | C7—H7 | 0.9500 |
N2—C5 | 1.274 (4) | C7—C8 | 1.384 (5) |
N3—C6 | 1.357 (4) | C8—H8 | 0.9500 |
N3—C10 | 1.328 (4) | C8—C9 | 1.383 (5) |
C1—H1A | 0.9900 | C9—H9 | 0.9500 |
C1—H1B | 0.9900 | C9—C10 | 1.390 (4) |
C1—C2 | 1.530 (4) | C10—H10 | 0.9500 |
C2—H2A | 0.9900 | O1—H1D | 0.838 (10) |
C2—H2B | 0.9900 | O1—H1C | 0.837 (10) |
C3—H3A | 0.9800 | ||
Cl2—Cu1—Cl1 | 102.95 (3) | H2A—C2—H2B | 108.1 |
N1—Cu1—Cl1 | 99.55 (7) | N1—C3—H3A | 109.5 |
N1—Cu1—Cl2 | 96.54 (7) | N1—C3—H3B | 109.5 |
N2—Cu1—Cl1 | 97.12 (7) | N1—C3—H3C | 109.5 |
N2—Cu1—Cl2 | 159.89 (8) | H3A—C3—H3B | 109.5 |
N2—Cu1—N1 | 81.17 (10) | H3A—C3—H3C | 109.5 |
N2—Cu1—N3 | 79.40 (10) | H3B—C3—H3C | 109.5 |
N3—Cu1—Cl1 | 96.13 (7) | N1—C4—H4A | 109.5 |
N3—Cu1—Cl2 | 97.08 (7) | N1—C4—H4B | 109.5 |
N3—Cu1—N1 | 156.35 (10) | N1—C4—H4C | 109.5 |
C2—N1—Cu1 | 105.54 (17) | H4A—C4—H4B | 109.5 |
C3—N1—Cu1 | 107.23 (18) | H4A—C4—H4C | 109.5 |
C3—N1—C2 | 110.9 (2) | H4B—C4—H4C | 109.5 |
C4—N1—Cu1 | 115.69 (18) | N2—C5—H5 | 122.2 |
C4—N1—C2 | 108.9 (2) | N2—C5—C6 | 115.6 (3) |
C4—N1—C3 | 108.6 (2) | C6—C5—H5 | 122.2 |
C1—N2—Cu1 | 117.93 (18) | N3—C6—C5 | 114.7 (2) |
C5—N2—Cu1 | 117.8 (2) | N3—C6—C7 | 121.9 (3) |
C5—N2—C1 | 124.2 (3) | C7—C6—C5 | 123.4 (3) |
C6—N3—Cu1 | 112.31 (19) | C6—C7—H7 | 120.4 |
C10—N3—Cu1 | 129.0 (2) | C6—C7—C8 | 119.1 (3) |
C10—N3—C6 | 118.7 (2) | C8—C7—H7 | 120.4 |
N2—C1—H1A | 110.5 | C7—C8—H8 | 120.5 |
N2—C1—H1B | 110.5 | C9—C8—C7 | 119.0 (3) |
N2—C1—C2 | 106.0 (2) | C9—C8—H8 | 120.5 |
H1A—C1—H1B | 108.7 | C8—C9—H9 | 120.6 |
C2—C1—H1A | 110.5 | C8—C9—C10 | 118.8 (3) |
C2—C1—H1B | 110.5 | C10—C9—H9 | 120.6 |
N1—C2—C1 | 110.2 (2) | N3—C10—C9 | 122.5 (3) |
N1—C2—H2A | 109.6 | N3—C10—H10 | 118.7 |
N1—C2—H2B | 109.6 | C9—C10—H10 | 118.7 |
C1—C2—H2A | 109.6 | H1D—O1—H1C | 102 (2) |
C1—C2—H2B | 109.6 | ||
Cu1—N1—C2—C1 | 47.7 (3) | C3—N1—C2—C1 | −68.1 (3) |
Cu1—N2—C1—C2 | 12.6 (3) | C4—N1—C2—C1 | 172.5 (2) |
Cu1—N2—C5—C6 | 4.5 (3) | C5—N2—C1—C2 | −165.9 (3) |
Cu1—N3—C6—C5 | −1.8 (3) | C5—C6—C7—C8 | −178.8 (3) |
Cu1—N3—C6—C7 | 179.9 (2) | C6—N3—C10—C9 | 0.8 (4) |
Cu1—N3—C10—C9 | −179.2 (2) | C6—C7—C8—C9 | 0.6 (4) |
N2—C1—C2—N1 | −39.5 (3) | C7—C8—C9—C10 | 0.0 (4) |
N2—C5—C6—N3 | −1.6 (4) | C8—C9—C10—N3 | −0.8 (4) |
N2—C5—C6—C7 | 176.7 (3) | C10—N3—C6—C5 | 178.2 (2) |
N3—C6—C7—C8 | −0.6 (4) | C10—N3—C6—C7 | −0.1 (4) |
C1—N2—C5—C6 | −176.9 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1D···Cl1i | 0.84 (1) | 2.45 (1) | 3.282 (3) | 173 (5) |
O1—H1C···Cl1ii | 0.84 (1) | 2.43 (1) | 3.252 (3) | 166 (4) |
C5—H5···Cl1iii | 0.95 | 2.73 | 3.669 (3) | 171 |
C9—H9···Cl2iv | 0.95 | 2.86 | 3.543 (3) | 130 |
Symmetry codes: (i) x+1/2, −y+1/2, z+1/2; (ii) x+1, y, z+1; (iii) x−1, y, z; (iv) −x+1, −y, −z. |
[Cu2(C11H15N2O)Cl3(C4H12N2)]·0.11H2O | F(000) = 1051 |
Mr = 514.77 | Dx = 1.631 Mg m−3 |
Monoclinic, P21/c | Cu Kα radiation, λ = 1.54178 Å |
a = 11.0838 (4) Å | Cell parameters from 6733 reflections |
b = 18.0949 (7) Å | θ = 4.8–68.2° |
c = 10.6610 (4) Å | µ = 6.12 mm−1 |
β = 101.474 (2)° | T = 150 K |
V = 2095.44 (14) Å3 | Needle, clear green |
Z = 4 | 0.08 × 0.06 × 0.04 mm |
Bruker APEXII CCD area-detector diffractometer | 3333 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.024 |
Absorption correction: multi-scan (SADABS; Bruker, 2010) | θmax = 68.2°, θmin = 4.1° |
Tmin = 0.654, Tmax = 0.753 | h = −11→13 |
11774 measured reflections | k = −19→21 |
3680 independent reflections | l = −11→12 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.022 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.056 | w = 1/[σ2(Fo2) + (0.0287P)2 + 1.0606P] where P = (Fo2 + 2Fc2)/3 |
S = 1.03 | (Δ/σ)max = 0.001 |
3680 reflections | Δρmax = 0.32 e Å−3 |
248 parameters | Δρmin = −0.28 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Cu1 | 0.79793 (2) | 0.56169 (2) | 0.73980 (2) | 0.01442 (8) | |
Cu2 | 0.69862 (2) | 0.39361 (2) | 0.68114 (2) | 0.01267 (8) | |
Cl1 | 0.59567 (4) | 0.62588 (3) | 0.64539 (4) | 0.02241 (11) | |
Cl2 | 0.75397 (4) | 0.47616 (3) | 0.88333 (4) | 0.02295 (11) | |
Cl3 | 0.85942 (4) | 0.32302 (2) | 0.65652 (4) | 0.02100 (11) | |
O1 | 0.76725 (11) | 0.48317 (7) | 0.60963 (11) | 0.0151 (3) | |
N1 | 0.85544 (14) | 0.64035 (9) | 0.87958 (15) | 0.0189 (3) | |
N2 | 0.90614 (13) | 0.61412 (8) | 0.64520 (14) | 0.0161 (3) | |
N3 | 0.52655 (14) | 0.43584 (9) | 0.63814 (16) | 0.0165 (3) | |
H3A | 0.503 (2) | 0.4342 (12) | 0.556 (2) | 0.017 (5)* | |
H3B | 0.533 (2) | 0.4801 (15) | 0.663 (2) | 0.024 (6)* | |
N4 | 0.61771 (14) | 0.31151 (8) | 0.76637 (14) | 0.0157 (3) | |
C1 | 0.96901 (18) | 0.67789 (11) | 0.71453 (19) | 0.0213 (4) | |
H1A | 0.9791 | 0.7178 | 0.6539 | 0.026* | |
H1B | 1.0515 | 0.6634 | 0.7625 | 0.026* | |
C2 | 0.88892 (18) | 0.70405 (11) | 0.80598 (19) | 0.0219 (4) | |
H2A | 0.9341 | 0.7413 | 0.8655 | 0.026* | |
H2B | 0.8133 | 0.7275 | 0.7571 | 0.026* | |
C3 | 0.75991 (19) | 0.66273 (12) | 0.9508 (2) | 0.0273 (5) | |
H3C | 0.6865 | 0.6794 | 0.8904 | 0.041* | |
H3D | 0.7913 | 0.7031 | 1.0096 | 0.041* | |
H3E | 0.7385 | 0.6205 | 0.9997 | 0.041* | |
C4 | 0.96456 (18) | 0.61355 (12) | 0.97277 (19) | 0.0262 (4) | |
H4A | 0.9411 | 0.5710 | 1.0195 | 0.039* | |
H4B | 0.9955 | 0.6532 | 1.0333 | 0.039* | |
H4C | 1.0291 | 0.5988 | 0.9270 | 0.039* | |
C5 | 0.92226 (16) | 0.59984 (10) | 0.53223 (17) | 0.0161 (4) | |
H5 | 0.9786 | 0.6302 | 0.4993 | 0.019* | |
C6 | 0.86234 (15) | 0.54160 (10) | 0.45045 (17) | 0.0140 (3) | |
C7 | 0.88041 (17) | 0.54119 (11) | 0.32361 (18) | 0.0182 (4) | |
H7 | 0.9342 | 0.5766 | 0.2983 | 0.022* | |
C8 | 0.82217 (18) | 0.49076 (11) | 0.23504 (17) | 0.0206 (4) | |
H8 | 0.8345 | 0.4916 | 0.1494 | 0.025* | |
C9 | 0.74469 (18) | 0.43840 (11) | 0.27382 (18) | 0.0203 (4) | |
H9 | 0.7030 | 0.4038 | 0.2134 | 0.024* | |
C10 | 0.72765 (17) | 0.43609 (10) | 0.39835 (18) | 0.0173 (4) | |
H10 | 0.6757 | 0.3992 | 0.4226 | 0.021* | |
C11 | 0.78550 (15) | 0.48712 (10) | 0.48998 (16) | 0.0132 (3) | |
C12 | 0.43951 (17) | 0.39331 (11) | 0.6993 (2) | 0.0232 (4) | |
H12A | 0.3886 | 0.3606 | 0.6354 | 0.028* | |
H12B | 0.3839 | 0.4276 | 0.7329 | 0.028* | |
C13 | 0.51174 (18) | 0.34742 (11) | 0.80794 (19) | 0.0215 (4) | |
H13A | 0.5419 | 0.3795 | 0.8828 | 0.026* | |
H13B | 0.4575 | 0.3092 | 0.8337 | 0.026* | |
C14 | 0.57543 (19) | 0.25295 (11) | 0.67056 (19) | 0.0229 (4) | |
H14A | 0.5221 | 0.2747 | 0.5953 | 0.034* | |
H14B | 0.5294 | 0.2155 | 0.7080 | 0.034* | |
H14C | 0.6469 | 0.2299 | 0.6451 | 0.034* | |
C15 | 0.69955 (18) | 0.27786 (12) | 0.87843 (19) | 0.0240 (4) | |
H15A | 0.7701 | 0.2548 | 0.8512 | 0.036* | |
H15B | 0.6539 | 0.2403 | 0.9162 | 0.036* | |
H15C | 0.7288 | 0.3162 | 0.9421 | 0.036* | |
O1W | 0.4947 (19) | 0.4479 (16) | 0.081 (2) | 0.084 (11) | 0.108 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.01696 (14) | 0.01273 (14) | 0.01364 (13) | −0.00351 (10) | 0.00323 (10) | −0.00212 (10) |
Cu2 | 0.01273 (13) | 0.01071 (14) | 0.01505 (13) | −0.00016 (10) | 0.00394 (10) | 0.00254 (10) |
Cl1 | 0.0169 (2) | 0.0237 (2) | 0.0246 (2) | 0.00368 (18) | −0.00074 (17) | −0.00630 (19) |
Cl2 | 0.0342 (3) | 0.0210 (2) | 0.0129 (2) | −0.00864 (19) | 0.00281 (17) | 0.00016 (17) |
Cl3 | 0.0164 (2) | 0.0176 (2) | 0.0312 (2) | 0.00427 (17) | 0.01032 (18) | 0.00640 (18) |
O1 | 0.0210 (6) | 0.0116 (6) | 0.0139 (6) | −0.0022 (5) | 0.0063 (5) | 0.0001 (5) |
N1 | 0.0182 (8) | 0.0187 (8) | 0.0193 (8) | −0.0027 (6) | 0.0027 (6) | −0.0053 (6) |
N2 | 0.0148 (7) | 0.0136 (7) | 0.0200 (8) | −0.0019 (6) | 0.0032 (6) | −0.0018 (6) |
N3 | 0.0167 (8) | 0.0148 (8) | 0.0174 (8) | 0.0000 (6) | 0.0018 (6) | 0.0006 (7) |
N4 | 0.0170 (7) | 0.0149 (7) | 0.0163 (7) | 0.0014 (6) | 0.0062 (6) | 0.0041 (6) |
C1 | 0.0219 (9) | 0.0170 (9) | 0.0254 (10) | −0.0089 (8) | 0.0059 (8) | −0.0049 (8) |
C2 | 0.0234 (9) | 0.0145 (9) | 0.0275 (10) | −0.0032 (8) | 0.0046 (8) | −0.0054 (8) |
C3 | 0.0266 (10) | 0.0310 (11) | 0.0258 (10) | −0.0024 (9) | 0.0087 (8) | −0.0123 (9) |
C4 | 0.0241 (10) | 0.0290 (11) | 0.0227 (10) | −0.0022 (9) | −0.0024 (8) | −0.0021 (9) |
C5 | 0.0132 (8) | 0.0149 (9) | 0.0206 (9) | −0.0008 (7) | 0.0046 (7) | 0.0033 (7) |
C6 | 0.0120 (8) | 0.0132 (8) | 0.0168 (8) | 0.0015 (7) | 0.0028 (7) | 0.0014 (7) |
C7 | 0.0172 (9) | 0.0187 (9) | 0.0201 (9) | 0.0005 (8) | 0.0074 (7) | 0.0026 (8) |
C8 | 0.0251 (9) | 0.0226 (10) | 0.0155 (9) | 0.0024 (8) | 0.0070 (7) | −0.0003 (8) |
C9 | 0.0241 (10) | 0.0180 (10) | 0.0179 (9) | 0.0009 (8) | 0.0018 (7) | −0.0032 (7) |
C10 | 0.0191 (9) | 0.0133 (9) | 0.0195 (9) | −0.0018 (7) | 0.0038 (7) | −0.0005 (7) |
C11 | 0.0131 (8) | 0.0114 (8) | 0.0153 (8) | 0.0036 (7) | 0.0034 (6) | 0.0020 (7) |
C12 | 0.0162 (9) | 0.0239 (10) | 0.0312 (10) | 0.0017 (8) | 0.0087 (8) | 0.0043 (8) |
C13 | 0.0206 (9) | 0.0229 (10) | 0.0238 (10) | 0.0015 (8) | 0.0114 (8) | 0.0025 (8) |
C14 | 0.0267 (10) | 0.0170 (9) | 0.0264 (10) | −0.0066 (8) | 0.0086 (8) | 0.0000 (8) |
C15 | 0.0240 (10) | 0.0247 (10) | 0.0240 (10) | 0.0030 (8) | 0.0067 (8) | 0.0105 (8) |
O1W | 0.048 (13) | 0.12 (2) | 0.081 (17) | 0.002 (13) | 0.006 (11) | −0.024 (15) |
Cu1—Cl1 | 2.5476 (5) | C3—H3D | 0.9800 |
Cu1—Cl2 | 2.2957 (5) | C3—H3E | 0.9800 |
Cu1—O1 | 1.9679 (12) | C4—H4A | 0.9800 |
Cu1—N1 | 2.0675 (15) | C4—H4B | 0.9800 |
Cu1—N2 | 1.9589 (15) | C4—H4C | 0.9800 |
Cu2—Cl2 | 2.5939 (5) | C5—H5 | 0.9500 |
Cu2—Cl3 | 2.2500 (5) | C5—C6 | 1.443 (3) |
Cu2—O1 | 2.0042 (12) | C6—C7 | 1.406 (3) |
Cu2—N3 | 2.0209 (16) | C6—C11 | 1.420 (2) |
Cu2—N4 | 2.0399 (15) | C7—H7 | 0.9500 |
O1—C11 | 1.333 (2) | C7—C8 | 1.378 (3) |
N1—C2 | 1.483 (3) | C8—H8 | 0.9500 |
N1—C3 | 1.477 (2) | C8—C9 | 1.395 (3) |
N1—C4 | 1.486 (2) | C9—H9 | 0.9500 |
N2—C1 | 1.469 (2) | C9—C10 | 1.378 (3) |
N2—C5 | 1.279 (2) | C10—H10 | 0.9500 |
N3—H3A | 0.87 (2) | C10—C11 | 1.403 (3) |
N3—H3B | 0.84 (3) | C12—H12A | 0.9900 |
N3—C12 | 1.483 (2) | C12—H12B | 0.9900 |
N4—C13 | 1.485 (2) | C12—C13 | 1.517 (3) |
N4—C14 | 1.482 (3) | C13—H13A | 0.9900 |
N4—C15 | 1.480 (2) | C13—H13B | 0.9900 |
C1—H1A | 0.9900 | C14—H14A | 0.9800 |
C1—H1B | 0.9900 | C14—H14B | 0.9800 |
C1—C2 | 1.519 (3) | C14—H14C | 0.9800 |
C2—H2A | 0.9900 | C15—H15A | 0.9800 |
C2—H2B | 0.9900 | C15—H15B | 0.9800 |
C3—H3C | 0.9800 | C15—H15C | 0.9800 |
Cl2—Cu1—Cl1 | 106.496 (19) | N1—C3—H3C | 109.5 |
O1—Cu1—Cl1 | 92.04 (4) | N1—C3—H3D | 109.5 |
O1—Cu1—Cl2 | 87.33 (4) | N1—C3—H3E | 109.5 |
O1—Cu1—N1 | 172.12 (6) | H3C—C3—H3D | 109.5 |
N1—Cu1—Cl1 | 95.27 (5) | H3C—C3—H3E | 109.5 |
N1—Cu1—Cl2 | 93.42 (5) | H3D—C3—H3E | 109.5 |
N2—Cu1—Cl1 | 99.01 (5) | N1—C4—H4A | 109.5 |
N2—Cu1—Cl2 | 154.49 (5) | N1—C4—H4B | 109.5 |
N2—Cu1—O1 | 91.39 (6) | N1—C4—H4C | 109.5 |
N2—Cu1—N1 | 84.55 (6) | H4A—C4—H4B | 109.5 |
Cl3—Cu2—Cl2 | 111.221 (19) | H4A—C4—H4C | 109.5 |
O1—Cu2—Cl2 | 78.78 (4) | H4B—C4—H4C | 109.5 |
O1—Cu2—Cl3 | 92.60 (4) | N2—C5—H5 | 117.2 |
O1—Cu2—N3 | 91.17 (6) | N2—C5—C6 | 125.67 (17) |
O1—Cu2—N4 | 172.78 (6) | C6—C5—H5 | 117.2 |
N3—Cu2—Cl2 | 91.56 (5) | C7—C6—C5 | 116.65 (16) |
N3—Cu2—Cl3 | 157.21 (5) | C7—C6—C11 | 119.36 (16) |
N3—Cu2—N4 | 84.13 (6) | C11—C6—C5 | 123.97 (16) |
N4—Cu2—Cl2 | 95.82 (4) | C6—C7—H7 | 119.1 |
N4—Cu2—Cl3 | 93.85 (4) | C8—C7—C6 | 121.71 (17) |
Cu1—Cl2—Cu2 | 83.156 (16) | C8—C7—H7 | 119.1 |
Cu1—O1—Cu2 | 109.94 (6) | C7—C8—H8 | 120.7 |
C11—O1—Cu1 | 126.76 (11) | C7—C8—C9 | 118.59 (17) |
C11—O1—Cu2 | 123.29 (11) | C9—C8—H8 | 120.7 |
C2—N1—Cu1 | 103.16 (11) | C8—C9—H9 | 119.5 |
C2—N1—C4 | 110.58 (15) | C10—C9—C8 | 121.09 (18) |
C3—N1—Cu1 | 114.17 (12) | C10—C9—H9 | 119.5 |
C3—N1—C2 | 109.84 (16) | C9—C10—H10 | 119.4 |
C3—N1—C4 | 108.49 (15) | C9—C10—C11 | 121.29 (17) |
C4—N1—Cu1 | 110.53 (12) | C11—C10—H10 | 119.4 |
C1—N2—Cu1 | 113.52 (12) | O1—C11—C6 | 122.37 (16) |
C5—N2—Cu1 | 126.99 (13) | O1—C11—C10 | 119.72 (16) |
C5—N2—C1 | 119.44 (16) | C10—C11—C6 | 117.91 (16) |
Cu2—N3—H3A | 107.4 (14) | N3—C12—H12A | 109.8 |
Cu2—N3—H3B | 105.4 (16) | N3—C12—H12B | 109.8 |
H3A—N3—H3B | 110 (2) | N3—C12—C13 | 109.21 (15) |
C12—N3—Cu2 | 111.79 (12) | H12A—C12—H12B | 108.3 |
C12—N3—H3A | 109.6 (14) | C13—C12—H12A | 109.8 |
C12—N3—H3B | 112.5 (16) | C13—C12—H12B | 109.8 |
C13—N4—Cu2 | 104.96 (11) | N4—C13—C12 | 109.90 (15) |
C14—N4—Cu2 | 108.70 (11) | N4—C13—H13A | 109.7 |
C14—N4—C13 | 110.99 (15) | N4—C13—H13B | 109.7 |
C15—N4—Cu2 | 113.96 (11) | C12—C13—H13A | 109.7 |
C15—N4—C13 | 109.47 (14) | C12—C13—H13B | 109.7 |
C15—N4—C14 | 108.74 (15) | H13A—C13—H13B | 108.2 |
N2—C1—H1A | 110.4 | N4—C14—H14A | 109.5 |
N2—C1—H1B | 110.4 | N4—C14—H14B | 109.5 |
N2—C1—C2 | 106.76 (15) | N4—C14—H14C | 109.5 |
H1A—C1—H1B | 108.6 | H14A—C14—H14B | 109.5 |
C2—C1—H1A | 110.4 | H14A—C14—H14C | 109.5 |
C2—C1—H1B | 110.4 | H14B—C14—H14C | 109.5 |
N1—C2—C1 | 109.70 (16) | N4—C15—H15A | 109.5 |
N1—C2—H2A | 109.7 | N4—C15—H15B | 109.5 |
N1—C2—H2B | 109.7 | N4—C15—H15C | 109.5 |
C1—C2—H2A | 109.7 | H15A—C15—H15B | 109.5 |
C1—C2—H2B | 109.7 | H15A—C15—H15C | 109.5 |
H2A—C2—H2B | 108.2 | H15B—C15—H15C | 109.5 |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3A···Cl1i | 0.87 (2) | 2.46 (2) | 3.2543 (17) | 153 (2) |
N3—H3B···Cl1 | 0.84 (2) | 2.74 (2) | 3.5207 (1) | 154 (2) |
C8—H8···Cl2ii | 0.95 | 2.81 | 3.6841 (19) | 153 |
O1W···Cl2i | 3.17 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, y, z−1. |
1 | Analogues of 1, average of 12 hits | 2 | Analogues of 2, average of 11 hits | |
D1 | 2.060 (2) | 2.06 (7) | 2.067 (2) | 2.01 (4) |
D2 | 1.978 (2) | 1.99 (4) | 1.959 (2) | 1.98 (3) |
D3 | 2.058 (2) | 2.06 (6) | 1.968 (1) | 1.969 (19) |
D4 | 2.2639 (8) | 2.240 (11) | 2.5477 (5) | 2.28 (3)sb 2.60 (5)ap |
D5 | 2.5014 (9) | 2.487 (17) | ||
D6 | 1.273 (3) | 1.269 (15) | 1.278 (3) | 1.281 (6) |
D7 | 2.004 (1) | 2.01 (3) | ||
D8 | 2.5939 (5) | 2.287 (19)sb 2.74 (12)ap | ||
D9 | 3.2525 (5) | 3.24 (10) |
Notes: sb = ligands at the square base of the polyhedron; ap = ligands at the apical position. |
Acknowledgements
The authors are grateful to Dr Déborah de Alencar Simoni, technician of the Institutional Single-Crystal XRD Facility, UNICAMP, Brazil, for the data collection.
Funding information
Funding for this research was provided by: Conselho Nacional de Desenvolvimento Científico e Tecnológico (scholarship No. 140466/2014-2 to Raphael E. F. de Paiva; scholarship No. 140707/2013-1 to Fernando R. G. Bergamini); Fundação de Amparo à Pesquisa do Estado de São Paulo (grant No. 2015/ 25114-4 to Pedro P. Corbi; scholarship No. 2015/20882-3 to Douglas H. Nakahata).
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