research communications
S)-2-[(2-hydroxybenzyl)amino]-4-methylpentanoato-κ2N,O}(1,10-phenanthroline-κ2N,N′)nickel(II)
and DFT study of bis{(aDepartment of Chemistry, College of Science, Sultan Qaboos University, PO Box 36 Al-Khod 123, Muscat, Sultanate of Oman, bOndokuz Mayıs University, Arts and Sciences Faculty, Department of Physics, 55139 Atakum–Samsun, Turkey, and cDepartment of Chemistry, National Taras Shevchenko University of Kiev, 64/13, Volodymyrska Street, City of Kyiv, 01601, Ukraine
*Correspondence e-mail: malinachem88@gmail.com
In the title compound, [Ni(C13H18NO3)2(C12H8N2)], the NiII cation shows a distorted octahedral coordination environment. It is formed by two N atoms from the phenanthroline ligand, as well as two N and two O atoms belonging to two 2-[(2-hydroxybenzyl)amino]-4-methylpentanoate ligands. Complex molecules are connected into layers propagating along the ab plane via hydrogen bonds formed by O atoms of carboxylate and phenoxide groups, which are further connected into a three-dimensional motif.
Keywords: crystal structure; nickel(II); phenanthroline; amine; leucine; salicylaldehyde; C—H⋯π interactions; hydrogen bonding.
CCDC reference: 1548336
1. Chemical context
The design and synthesis of metal complexes have attracted considerable attention for their potential applications in catalysis, magnetism, materials science and pharmaceutical chemistry (Che & Siu, 2010). Mononuclear ethylenediaminediacetate complexes can be used to bind and cleave DNA under physiological conditions (An et al., 2006) and binuclear complexes containing bipyridyl or phenanthroline units in their structure show antiviral activity, as well as inhibition of proviral DNA synthesis (Rajendiran et al., 2007). On the other hand, using bifunctional ligands that are capable of simultaneously coordinating to a metal centre and providing hydrogen bonding gives important experimental data for a better understanding of the key tools in crystal engineering (Burrows, 2004). Metal complexes of 1,10-phenanthroline (phen) and its derivatives are of increasing interest because of their versatile roles in many fields, such as analytical chemistry (Chalk & Tyson, 1994), catalysis (Samnani et al., 1996), electrochemical polymerization (Bachas et al., 1997) and biochemistry (Sammes & Yahioglu, 1994). 1,10-Phenanthroline is a bidentate chelating ligand with notable coordination ability for transition metal cations. Over the last few decades, the complex formation of transition metal ions with amino acids has also been studied extensively (Auclair et al., 1984). Amino acid–metallic ion interactions are found to be responsible for enzymatic activity and the stability of protein structures (Dinelli et al., 2010). Nickel is also essential for the healthy life of animals since it is associated with several enzymes (Poellot et al., 1990) and plays a role in physiological processes as a cofactor in the absorption of iron from the intestine (Nielsen, 1980). Any change in its concentration leads to metabolic disorder (Kolodziej, 1994). With the discovery of the biological importance of nickel, it is essential to study its complex formation with amino acids in order to gain a better understanding of the functions of their complexes (Faizi & Sharkina, 2015). Therefore, we report here the preparation and the of a nickel(II) complex with the formula: [Ni(C13H18NO3)2(C12H8N2)], (I).
2. Structural commentary
The complex molecule of I, represented in Fig. 1, contains one crystallographically independent NiII cation, which is octahedrally coordinated by two molecules of deprotonated 2-[(2-hydroxybenzyl)amino]-4-methylpentanoic acid via their N atoms and one of the carboxylate atoms each. The coordination environment is completed by one bidentate phenanthroline ligand. The C—O bond lengths in the deprotonated carboxylic acid groups differ significantly [1.239 (2) and 1.292 (2) Å], which is typical for monodentate carboxylate groups (Wörl et al., 2005a,b).
The values of the Ni—O bond lengths are similar to those reported in the literature for octahedral carboxylate nickel(II) complexes II–IV (see §5). However, the corresponding Ni—N separations of 2.101 (3)–2.149 (3) Å are somewhat shorter than found for III–IV and similar to that observed in II.
Consequently, the slightly distorted octahedral coordination is stabilized by intramolecular N1—H1A⋯O1 and N2—H2A⋯O2 hydrogen bonds between O atoms of phenoxide moieties and amino groups (Table 1 and Fig. 1) and a weak π–π interaction between the phenanthroline ligand and the phenoxide unit [centroid(N4/C27–C30/C38)⋯centroid(C20–C25) = 3.530 (2) Å].
3. Supramolecular features
As shown in Fig. 2, molecules of I are united into layers along the ab plane via hydrogen bonds formed between the O atoms of carboxylate and phenoxide groups (Table 1). The layers are stacked via weak C—H⋯π interactions between the H atoms of phenanthroline ligands and phenoxide moieties [H32⋯centroid(C1–C6) = 3.390 (5) Å and H23⋯centroid(C1–C6) = 3.477 (3) Å] (Fig. 3).
4. DFT study
The molecular structure used in the theoretical studies of the Ni complex was taken from the X-ray diffraction results, keeping all distances, angles and dihedral angles frozen. Single-point DFT calculations have been carried out using the scalar zeroth-order regular approximation Hamiltonian (Wüllen, 1998). Single-point ground-state calculations were carried out using the hybrid B3LYP functional as implemented in ORCA (Lee et al., 1988). The present calculation was performed using the additional approximation that the Coulomb integrals are approximated by sum of atom centred s, p, d functions, the auxiliary (or fitting) basis set (Yilmaz et al., 2006). This allows for efficient treatment of the Coulomb interactions and hence reduces calculation times. The Def2-TZVP main and Def2-TZVP/J auxiliary basis sets were used (Pantazis et al., 2008). The main basis set is of [5s3p2d] quality for Ni, (5s2p1d) for C, N and O, and (2s) for H (Weigend & Ahlrichs, 2005).
The LUMO and HOMO ΔE) between the HOMO and LUMO are more polarizable, thereby acting as soft molecules with higher chemical reactivity. However, complexes with a large energy gap offer greater stability and low chemical reactivity compared to those with a small HOMO–LUMO energy gap. The DFT study of I revealed that the HOMO and HOMO-1 are localized on the N1, N2, O4, O5, O3, O6, C13 and C14 atoms of the amino acid ligand. In addition, the respective molecular orbitals are also partially localized on the NiII cation, namely in the dx2-y2 orbital (Fig. 4). In contrast, LUMO and LUMO+1 are totally delocalized over the phenanthroline moiety. It could therefore be stated that the HOMO and LUMO are mainly composed of σ- and π-type orbitals, respectively, and that intramolecular charge transfer occurs from the amino acid moiety to the phenanthroline ligand. The HOMO–LUMO gap of I was calculated to 0.04212 a.u. and the frontier molecular orbital energies of I are also given in Fig. 4. A comparison of selected geometric data for I from calculated (DFT) and X-ray data is given in Table 2.
parameters are significantly accountable for the charge transfer, chemical reactivity and kinetic/thermodynamic stability of a molecule. Metal complexes with a small energy gap (
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5. Database survey
A search of the Cambridge Structural Database (CSD, Version 5.38, update February 2017; Groom et al., 2016) revealed the structures of three similar compounds, viz. (II) (IVIKOO; Ji et al., 2011), (III) (FATQAT; Ma et al., 2004) and (IV) (YOWKEA; Skoulika et al., 1995); all three nickel(II) complexes have similar N4O2 coordination environments formed by aminocarboxylate and phenanthroline ligands.
6. Synthesis and crystallization
For the preparation of 2-[(2-hydroxybenzyl)amino]-4-methylpentanoic acid (HAMA), L-leucine (1.00 g, 6.71 mmol) and LiOH·H2O (0.284 g, 6.77 mmol) in anhydrous methanol (30 ml) were stirred for 30 min to dissolve. A methanolic solution of salicylaldehyde (1.44 g, 6.72 mmol) was added dropwise to the above solution. The solution was stirred for 1 h and then treated with sodium borohydride (0.248 g, 6.71 mmol) with constant stirring. The solvent was evaporated and the resulting sticky mass was dissolved in water. A cloudy solution was obtained, which was then acidified with dilute HCl. By maintaining the pH of the solution in the range 5–7 the ligand precipitated as a colourless solid. The solid was filtered off, washed thoroughly with water and finally dried inside a vacuum desiccator (yield 2.08 g, 85%).
For the preparation of the title compound, HAMA (0.500 g, 1.43 mmol) was deprotonated with LiOH·H2O (0.060 g, 1.44 mmol) in anhydrous methanol (25 ml), which resulted in a clear colourless solution after 30 min. A methanolic solution of Ni(NO3)2·6H2O (0.17 g, 0.71 mmol) was added dropwise to the ligand solution with stirring. The colour of the solution changed to green immediately. Phenanthroline (0.13 g, 0.71 mmol) was then added and the reaction mixture was stirred at room temperature for 16 h. The solution was evaporated to dryness with a rotary evaporator. Blue block-shaped crystals, suitable for single-crystal X-ray analysis, were obtained by slow diffusion of diethyl ether into a methanolic solution of the crude solid over a period of 2–3 d. The crystals were filtered off and washed with diethyl ether (yield 74%).
7. Refinement
Crystal data, data collection and structure . The N—H hydrogens were located in a difference Fourier map and refined without constraints. The O—H hydrogens were also located in a difference Fourier map but were constrained to ride on their parent atoms, with Uiso(H) = 1.5Ueq(O). The C-bound H atoms were included in calculated positions and treated as riding atoms, with C—H = 0.95 Å and Uiso(H) = 1.2–1.5Ueq(C).
details are summarized in Table 3
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Supporting information
CCDC reference: 1548336
https://doi.org/10.1107/S2056989017012014/im2482sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017012014/im2482Isup2.hkl
Data collection: APEX2 (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2008), SHELXTL (Sheldrick, 2008) and ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL2016 (Sheldrick, 2015b) and PLATON (Spek, 2009).
[Ni(C13H18NO3)2(C12H8N2)] | Dx = 1.263 Mg m−3 |
Mr = 711.48 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 9936 reflections |
a = 12.9336 (4) Å | θ = 0.9–0.9° |
b = 14.5249 (4) Å | µ = 0.57 mm−1 |
c = 19.9141 (5) Å | T = 296 K |
V = 3741.05 (18) Å3 | Block, blue |
Z = 4 | 0.30 × 0.22 × 0.20 mm |
F(000) = 1504 |
Bruker APEXII CCD area detector diffractometer | 8568 independent reflections |
Radiation source: fine-focus sealed tube, x-ray | 6012 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
phi and ω scans | θmax = 27.5°, θmin = 1.7° |
Absorption correction: multi-scan multi-scan | h = −16→16 |
Tmin = 0.848, Tmax = 0.895 | k = −18→18 |
29587 measured reflections | l = −25→25 |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.043 | w = 1/[σ2(Fo2) + (0.0876P)2] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.133 | (Δ/σ)max = 0.001 |
S = 0.95 | Δρmax = 0.76 e Å−3 |
8568 reflections | Δρmin = −0.29 e Å−3 |
449 parameters | Absolute structure: Refined as an inversion twin |
18 restraints | Absolute structure parameter: −0.010 (18) |
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. |
Refinement. Refined as a 2-component inversion twin |
x | y | z | Uiso*/Ueq | ||
Ni1 | 0.52225 (3) | 0.50277 (4) | 0.46103 (2) | 0.04058 (16) | |
O5 | 0.6501 (2) | 0.5145 (2) | 0.52079 (13) | 0.0468 (7) | |
O2 | 0.3621 (3) | 0.7541 (3) | 0.41899 (14) | 0.0724 (10) | |
H2 | 0.311477 | 0.787276 | 0.413623 | 0.109* | |
O1 | 0.6688 (2) | 0.2074 (2) | 0.43473 (17) | 0.0571 (8) | |
H1 | 0.720827 | 0.175450 | 0.431692 | 0.086* | |
O4 | 0.4054 (2) | 0.5004 (3) | 0.53063 (12) | 0.0514 (6) | |
O6 | 0.7370 (2) | 0.6064 (2) | 0.58909 (15) | 0.0616 (9) | |
O3 | 0.3183 (3) | 0.4110 (3) | 0.60140 (16) | 0.0679 (9) | |
N4 | 0.4109 (2) | 0.4992 (3) | 0.38398 (15) | 0.0475 (7) | |
N2 | 0.5284 (3) | 0.6495 (2) | 0.47445 (15) | 0.0419 (8) | |
H2A | 0.457126 | 0.670131 | 0.481619 | 0.050* | |
N3 | 0.6159 (3) | 0.4852 (3) | 0.37583 (17) | 0.0503 (9) | |
N1 | 0.5230 (3) | 0.3595 (2) | 0.48649 (15) | 0.0435 (8) | |
H1A | 0.595472 | 0.341573 | 0.492509 | 0.052* | |
C38 | 0.4518 (3) | 0.4861 (3) | 0.3217 (2) | 0.0502 (10) | |
C37 | 0.5622 (4) | 0.4787 (3) | 0.3174 (2) | 0.0483 (10) | |
C1 | 0.5863 (3) | 0.1533 (3) | 0.45023 (19) | 0.0478 (10) | |
C20 | 0.4058 (4) | 0.7348 (3) | 0.3577 (2) | 0.0517 (11) | |
C25 | 0.5103 (4) | 0.7109 (3) | 0.35645 (19) | 0.0482 (10) | |
C6 | 0.4888 (3) | 0.1959 (3) | 0.45109 (18) | 0.0470 (9) | |
C14 | 0.6642 (3) | 0.5909 (3) | 0.54962 (19) | 0.0459 (9) | |
C13 | 0.3911 (3) | 0.4256 (3) | 0.5619 (2) | 0.0469 (10) | |
C2 | 0.5965 (4) | 0.0606 (3) | 0.4652 (2) | 0.0603 (12) | |
H2B | 0.661691 | 0.033535 | 0.465867 | 0.072* | |
C33 | 0.6104 (5) | 0.4661 (3) | 0.2544 (2) | 0.0616 (13) | |
C7 | 0.4781 (3) | 0.2962 (3) | 0.4355 (2) | 0.0482 (9) | |
H7A | 0.511075 | 0.308224 | 0.392633 | 0.058* | |
H7B | 0.405176 | 0.310368 | 0.430582 | 0.058* | |
C9 | 0.5481 (4) | 0.3555 (4) | 0.6112 (2) | 0.0568 (12) | |
H9A | 0.593990 | 0.407310 | 0.603534 | 0.068* | |
H9B | 0.509724 | 0.367962 | 0.652028 | 0.068* | |
C30 | 0.3934 (4) | 0.4825 (3) | 0.2632 (2) | 0.0652 (14) | |
C8 | 0.4719 (3) | 0.3501 (3) | 0.55296 (18) | 0.0464 (10) | |
H8 | 0.436947 | 0.290295 | 0.554666 | 0.056* | |
C15 | 0.5844 (3) | 0.6659 (3) | 0.5380 (2) | 0.0488 (9) | |
H15 | 0.620696 | 0.724908 | 0.534388 | 0.059* | |
C21 | 0.3505 (4) | 0.7395 (3) | 0.2990 (2) | 0.0633 (12) | |
H21 | 0.280440 | 0.753963 | 0.300120 | 0.076* | |
C24 | 0.5575 (4) | 0.6950 (3) | 0.2947 (2) | 0.0569 (11) | |
H24 | 0.627329 | 0.679860 | 0.293289 | 0.068* | |
C5 | 0.4047 (4) | 0.1405 (4) | 0.4663 (2) | 0.0647 (13) | |
H5 | 0.339253 | 0.166923 | 0.467603 | 0.078* | |
C16 | 0.5130 (5) | 0.6701 (4) | 0.5987 (2) | 0.0756 (15) | |
H16A | 0.554693 | 0.668247 | 0.639188 | 0.091* | |
H16B | 0.469059 | 0.616033 | 0.598668 | 0.091* | |
C4 | 0.4145 (5) | 0.0476 (4) | 0.4798 (3) | 0.0767 (17) | |
H4 | 0.356250 | 0.012325 | 0.489077 | 0.092* | |
C23 | 0.5026 (5) | 0.7013 (3) | 0.2357 (2) | 0.0642 (13) | |
H23 | 0.535243 | 0.691361 | 0.194712 | 0.077* | |
C22 | 0.3988 (5) | 0.7226 (4) | 0.2379 (2) | 0.0678 (14) | |
H22 | 0.360883 | 0.725703 | 0.198237 | 0.081* | |
C32 | 0.5485 (6) | 0.4609 (4) | 0.1963 (3) | 0.0774 (16) | |
H32 | 0.579803 | 0.451734 | 0.154833 | 0.093* | |
C26 | 0.5726 (4) | 0.7091 (3) | 0.4201 (2) | 0.0526 (10) | |
H26A | 0.641737 | 0.687488 | 0.409610 | 0.063* | |
H26B | 0.578654 | 0.771477 | 0.436947 | 0.063* | |
C34 | 0.7167 (5) | 0.4601 (4) | 0.2532 (3) | 0.0755 (16) | |
H34 | 0.751273 | 0.451436 | 0.212747 | 0.091* | |
C28 | 0.2451 (4) | 0.5091 (4) | 0.3321 (3) | 0.0772 (15) | |
H28 | 0.174436 | 0.518730 | 0.337209 | 0.093* | |
C31 | 0.4447 (7) | 0.4688 (4) | 0.1996 (2) | 0.086 (2) | |
H31 | 0.405790 | 0.465412 | 0.160442 | 0.104* | |
C3 | 0.5097 (5) | 0.0080 (4) | 0.4792 (2) | 0.0736 (14) | |
H3 | 0.516635 | −0.054468 | 0.488318 | 0.088* | |
C29 | 0.2855 (5) | 0.4945 (5) | 0.2700 (3) | 0.0809 (16) | |
H29 | 0.242723 | 0.492516 | 0.232541 | 0.097* | |
C27 | 0.3098 (3) | 0.5095 (4) | 0.3884 (2) | 0.0614 (12) | |
H27 | 0.280372 | 0.517393 | 0.430589 | 0.074* | |
C36 | 0.7183 (4) | 0.4780 (4) | 0.3723 (3) | 0.0621 (13) | |
H36 | 0.756573 | 0.480433 | 0.411765 | 0.075* | |
C10 | 0.6139 (4) | 0.2694 (4) | 0.6222 (3) | 0.0733 (15) | |
H10 | 0.643633 | 0.252149 | 0.578763 | 0.088* | |
C35 | 0.7705 (5) | 0.4669 (4) | 0.3114 (3) | 0.0821 (17) | |
H35 | 0.842317 | 0.464102 | 0.310735 | 0.098* | |
C11 | 0.7018 (5) | 0.2873 (6) | 0.6694 (3) | 0.105 (2) | |
H11A | 0.741147 | 0.339042 | 0.653607 | 0.157* | |
H11B | 0.745548 | 0.233966 | 0.671362 | 0.157* | |
H11C | 0.675180 | 0.300390 | 0.713330 | 0.157* | |
C12 | 0.5484 (7) | 0.1884 (5) | 0.6466 (4) | 0.118 (3) | |
H12A | 0.531973 | 0.196611 | 0.693223 | 0.177* | |
H12B | 0.586403 | 0.132159 | 0.640902 | 0.177* | |
H12C | 0.485621 | 0.185509 | 0.620937 | 0.177* | |
C17 | 0.4436 (7) | 0.7575 (8) | 0.6008 (3) | 0.127 (2) | |
H17 | 0.417295 | 0.771165 | 0.555691 | 0.153* | |
C19 | 0.3515 (8) | 0.7320 (10) | 0.6487 (5) | 0.198 (5) | |
H19A | 0.345722 | 0.666232 | 0.651790 | 0.297* | |
H19B | 0.288408 | 0.756982 | 0.631046 | 0.297* | |
H19C | 0.364186 | 0.757147 | 0.692486 | 0.297* | |
C18 | 0.5090 (12) | 0.8401 (8) | 0.6272 (5) | 0.193 (4) | |
H18A | 0.532140 | 0.827174 | 0.672069 | 0.290* | |
H18B | 0.467315 | 0.894785 | 0.627429 | 0.290* | |
H18C | 0.567741 | 0.849136 | 0.598544 | 0.290* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni1 | 0.0418 (2) | 0.0431 (3) | 0.0368 (2) | 0.0001 (3) | −0.00271 (18) | 0.0003 (2) |
O5 | 0.0454 (13) | 0.0433 (19) | 0.0517 (14) | −0.0012 (14) | −0.0096 (11) | −0.0007 (13) |
O2 | 0.082 (2) | 0.090 (3) | 0.0458 (17) | 0.040 (2) | 0.0103 (15) | 0.0084 (16) |
O1 | 0.0533 (16) | 0.0481 (19) | 0.0699 (19) | −0.0028 (15) | −0.0016 (15) | 0.0030 (15) |
O4 | 0.0505 (14) | 0.0540 (18) | 0.0497 (14) | 0.0091 (18) | 0.0030 (11) | −0.0002 (18) |
O6 | 0.0625 (18) | 0.056 (2) | 0.0662 (19) | −0.0065 (15) | −0.0276 (16) | −0.0032 (15) |
O3 | 0.0606 (18) | 0.074 (2) | 0.070 (2) | −0.0105 (17) | 0.0182 (17) | −0.0040 (17) |
N4 | 0.0471 (16) | 0.0445 (19) | 0.0510 (17) | −0.001 (2) | −0.0075 (13) | 0.0064 (19) |
N2 | 0.0456 (18) | 0.0416 (19) | 0.0386 (16) | 0.0022 (16) | −0.0017 (15) | 0.0042 (13) |
N3 | 0.0548 (19) | 0.050 (3) | 0.0459 (17) | 0.0001 (18) | 0.0046 (14) | 0.0006 (17) |
N1 | 0.0477 (19) | 0.045 (2) | 0.0383 (16) | −0.0025 (17) | −0.0040 (15) | −0.0011 (13) |
C38 | 0.072 (3) | 0.037 (3) | 0.043 (2) | −0.004 (2) | −0.0118 (17) | 0.0045 (17) |
C37 | 0.070 (2) | 0.034 (3) | 0.041 (2) | −0.0006 (19) | 0.0002 (19) | 0.0013 (16) |
C1 | 0.061 (2) | 0.042 (2) | 0.041 (2) | −0.007 (2) | −0.0039 (18) | 0.0013 (17) |
C20 | 0.069 (3) | 0.042 (3) | 0.044 (2) | 0.013 (2) | 0.003 (2) | 0.0062 (18) |
C25 | 0.066 (3) | 0.036 (2) | 0.042 (2) | 0.002 (2) | 0.0048 (19) | 0.0047 (16) |
C6 | 0.055 (2) | 0.046 (2) | 0.040 (2) | −0.005 (2) | −0.0035 (18) | −0.0070 (17) |
C14 | 0.051 (2) | 0.046 (3) | 0.041 (2) | −0.0065 (19) | −0.0032 (17) | 0.0009 (18) |
C13 | 0.044 (2) | 0.056 (3) | 0.040 (2) | −0.009 (2) | −0.0013 (17) | −0.0047 (19) |
C2 | 0.082 (3) | 0.044 (3) | 0.055 (3) | −0.003 (2) | −0.004 (2) | −0.002 (2) |
C33 | 0.101 (4) | 0.037 (3) | 0.047 (2) | 0.000 (2) | 0.007 (3) | −0.0041 (18) |
C7 | 0.054 (2) | 0.047 (3) | 0.043 (2) | 0.003 (2) | −0.0104 (19) | −0.0044 (17) |
C9 | 0.074 (3) | 0.059 (3) | 0.038 (2) | −0.006 (2) | −0.003 (2) | −0.0003 (19) |
C30 | 0.095 (4) | 0.045 (3) | 0.055 (3) | −0.011 (3) | −0.025 (2) | 0.006 (2) |
C8 | 0.055 (2) | 0.046 (3) | 0.038 (2) | −0.0071 (19) | −0.0025 (17) | 0.0020 (16) |
C15 | 0.058 (2) | 0.046 (2) | 0.043 (2) | −0.0005 (19) | −0.008 (2) | −0.0009 (18) |
C21 | 0.077 (3) | 0.058 (3) | 0.055 (3) | 0.011 (3) | −0.008 (2) | 0.009 (2) |
C24 | 0.072 (3) | 0.050 (3) | 0.049 (2) | 0.004 (2) | 0.014 (2) | 0.008 (2) |
C5 | 0.065 (3) | 0.072 (4) | 0.057 (3) | −0.016 (3) | 0.008 (2) | −0.016 (3) |
C16 | 0.083 (3) | 0.099 (4) | 0.044 (2) | 0.026 (3) | −0.003 (2) | −0.016 (2) |
C4 | 0.097 (4) | 0.062 (4) | 0.071 (3) | −0.035 (3) | 0.021 (3) | −0.015 (3) |
C23 | 0.097 (4) | 0.052 (3) | 0.044 (2) | 0.008 (3) | 0.012 (2) | 0.0053 (19) |
C22 | 0.100 (4) | 0.062 (3) | 0.041 (2) | 0.001 (3) | −0.011 (2) | 0.007 (2) |
C32 | 0.126 (5) | 0.058 (3) | 0.048 (3) | 0.009 (3) | 0.000 (3) | −0.007 (2) |
C26 | 0.059 (2) | 0.047 (3) | 0.051 (2) | −0.001 (2) | 0.004 (2) | 0.0077 (19) |
C34 | 0.104 (4) | 0.061 (3) | 0.061 (3) | −0.001 (3) | 0.033 (3) | −0.008 (2) |
C28 | 0.057 (2) | 0.072 (4) | 0.103 (4) | −0.010 (3) | −0.031 (3) | 0.015 (4) |
C31 | 0.159 (6) | 0.060 (4) | 0.040 (3) | −0.002 (4) | −0.029 (3) | −0.003 (2) |
C3 | 0.119 (4) | 0.043 (3) | 0.059 (3) | −0.021 (4) | 0.014 (3) | 0.001 (2) |
C29 | 0.096 (4) | 0.068 (4) | 0.078 (3) | −0.013 (4) | −0.044 (3) | 0.013 (3) |
C27 | 0.057 (2) | 0.058 (3) | 0.069 (3) | −0.005 (3) | −0.006 (2) | 0.014 (3) |
C36 | 0.055 (2) | 0.068 (4) | 0.063 (3) | 0.004 (2) | 0.010 (2) | −0.001 (2) |
C10 | 0.073 (3) | 0.088 (4) | 0.059 (3) | 0.015 (3) | −0.012 (3) | 0.011 (3) |
C35 | 0.074 (3) | 0.085 (5) | 0.087 (4) | 0.000 (3) | 0.026 (3) | −0.019 (3) |
C11 | 0.084 (4) | 0.155 (7) | 0.075 (4) | 0.013 (4) | −0.019 (3) | 0.025 (4) |
C12 | 0.150 (7) | 0.074 (5) | 0.129 (6) | −0.005 (5) | −0.048 (5) | 0.043 (4) |
C17 | 0.133 (5) | 0.179 (6) | 0.069 (3) | 0.056 (4) | −0.008 (3) | −0.025 (4) |
C19 | 0.143 (7) | 0.323 (12) | 0.128 (6) | 0.110 (8) | 0.014 (6) | −0.057 (8) |
C18 | 0.293 (11) | 0.140 (8) | 0.147 (7) | 0.083 (8) | −0.016 (9) | −0.040 (6) |
Ni1—O5 | 2.044 (2) | C15—C16 | 1.522 (7) |
Ni1—O4 | 2.051 (3) | C15—H15 | 0.9800 |
Ni1—N3 | 2.101 (3) | C21—C22 | 1.390 (7) |
Ni1—N4 | 2.105 (3) | C21—H21 | 0.9300 |
Ni1—N1 | 2.141 (3) | C24—C23 | 1.376 (7) |
Ni1—N2 | 2.149 (3) | C24—H24 | 0.9300 |
O5—C14 | 1.262 (5) | C5—C4 | 1.382 (8) |
O2—C20 | 1.373 (5) | C5—H5 | 0.9300 |
O2—H2 | 0.8200 | C16—C17 | 1.555 (10) |
O1—C1 | 1.360 (5) | C16—H16A | 0.9700 |
O1—H1 | 0.8200 | C16—H16B | 0.9700 |
O4—C13 | 1.265 (6) | C4—C3 | 1.359 (8) |
O6—C14 | 1.247 (5) | C4—H4 | 0.9300 |
O3—C13 | 1.245 (5) | C23—C22 | 1.379 (8) |
N4—C27 | 1.318 (5) | C23—H23 | 0.9300 |
N4—C38 | 1.362 (5) | C22—H22 | 0.9300 |
N2—C15 | 1.477 (5) | C32—C31 | 1.348 (9) |
N2—C26 | 1.500 (5) | C32—H32 | 0.9300 |
N2—H2A | 0.9800 | C26—H26A | 0.9700 |
N3—C36 | 1.330 (6) | C26—H26B | 0.9700 |
N3—C37 | 1.359 (5) | C34—C35 | 1.355 (9) |
N1—C8 | 1.486 (5) | C34—H34 | 0.9300 |
N1—C7 | 1.489 (5) | C28—C29 | 1.359 (8) |
N1—H1A | 0.9800 | C28—C27 | 1.398 (6) |
C38—C30 | 1.389 (6) | C28—H28 | 0.9300 |
C38—C37 | 1.433 (6) | C31—H31 | 0.9300 |
C37—C33 | 1.414 (6) | C3—H3 | 0.9300 |
C1—C2 | 1.386 (6) | C29—H29 | 0.9300 |
C1—C6 | 1.405 (6) | C27—H27 | 0.9300 |
C20—C21 | 1.373 (6) | C36—C35 | 1.397 (7) |
C20—C25 | 1.395 (7) | C36—H36 | 0.9300 |
C25—C24 | 1.392 (6) | C10—C11 | 1.497 (8) |
C25—C26 | 1.502 (6) | C10—C12 | 1.529 (9) |
C6—C5 | 1.386 (6) | C10—H10 | 0.9800 |
C6—C7 | 1.496 (6) | C35—H35 | 0.9300 |
C14—C15 | 1.519 (6) | C11—H11A | 0.9600 |
C13—C8 | 1.525 (6) | C11—H11B | 0.9600 |
C2—C3 | 1.386 (7) | C11—H11C | 0.9600 |
C2—H2B | 0.9300 | C12—H12A | 0.9600 |
C33—C34 | 1.377 (9) | C12—H12B | 0.9600 |
C33—C32 | 1.408 (8) | C12—H12C | 0.9600 |
C7—H7A | 0.9700 | C17—C19 | 1.570 (14) |
C7—H7B | 0.9700 | C17—C18 | 1.560 (15) |
C9—C10 | 1.529 (8) | C17—H17 | 0.9800 |
C9—C8 | 1.524 (6) | C19—H19A | 0.9600 |
C9—H9A | 0.9700 | C19—H19B | 0.9600 |
C9—H9B | 0.9700 | C19—H19C | 0.9600 |
C30—C29 | 1.413 (8) | C18—H18A | 0.9600 |
C30—C31 | 1.444 (8) | C18—H18B | 0.9600 |
C8—H8 | 0.9800 | C18—H18C | 0.9600 |
O5—Ni1—O4 | 101.77 (11) | C20—C21—C22 | 120.2 (5) |
O5—Ni1—N3 | 90.80 (12) | C20—C21—H21 | 119.9 |
O4—Ni1—N3 | 165.66 (13) | C22—C21—H21 | 119.9 |
O5—Ni1—N4 | 168.45 (12) | C23—C24—C25 | 121.1 (4) |
O4—Ni1—N4 | 89.30 (11) | C23—C24—H24 | 119.4 |
N3—Ni1—N4 | 78.64 (13) | C25—C24—H24 | 119.4 |
O5—Ni1—N1 | 86.54 (13) | C4—C5—C6 | 122.5 (5) |
O4—Ni1—N1 | 80.03 (14) | C4—C5—H5 | 118.7 |
N3—Ni1—N1 | 94.04 (15) | C6—C5—H5 | 118.7 |
N4—Ni1—N1 | 98.73 (16) | C15—C16—C17 | 113.8 (5) |
O5—Ni1—N2 | 79.32 (13) | C15—C16—H16A | 108.8 |
O4—Ni1—N2 | 87.72 (14) | C17—C16—H16A | 108.8 |
N3—Ni1—N2 | 101.52 (15) | C15—C16—H16B | 108.8 |
N4—Ni1—N2 | 98.07 (16) | C17—C16—H16B | 108.8 |
N1—Ni1—N2 | 159.02 (12) | H16A—C16—H16B | 107.7 |
C14—O5—Ni1 | 117.1 (3) | C3—C4—C5 | 119.6 (5) |
C20—O2—H2 | 109.5 | C3—C4—H4 | 120.2 |
C1—O1—H1 | 109.5 | C5—C4—H4 | 120.2 |
C13—O4—Ni1 | 117.1 (3) | C22—C23—C24 | 119.4 (4) |
C27—N4—C38 | 117.5 (3) | C22—C23—H23 | 120.3 |
C27—N4—Ni1 | 128.8 (3) | C24—C23—H23 | 120.3 |
C38—N4—Ni1 | 113.6 (2) | C23—C22—C21 | 120.3 (4) |
C15—N2—C26 | 109.8 (3) | C23—C22—H22 | 119.8 |
C15—N2—Ni1 | 106.5 (2) | C21—C22—H22 | 119.8 |
C26—N2—Ni1 | 119.8 (3) | C31—C32—C33 | 121.5 (5) |
C15—N2—H2A | 106.7 | C31—C32—H32 | 119.3 |
C26—N2—H2A | 106.7 | C33—C32—H32 | 119.3 |
Ni1—N2—H2A | 106.7 | N2—C26—C25 | 114.5 (4) |
C36—N3—C37 | 117.3 (4) | N2—C26—H26A | 108.6 |
C36—N3—Ni1 | 128.8 (3) | C25—C26—H26A | 108.6 |
C37—N3—Ni1 | 113.9 (3) | N2—C26—H26B | 108.6 |
C8—N1—C7 | 112.1 (3) | C25—C26—H26B | 108.6 |
C8—N1—Ni1 | 107.4 (2) | H26A—C26—H26B | 107.6 |
C7—N1—Ni1 | 115.9 (2) | C35—C34—C33 | 119.6 (5) |
C8—N1—H1A | 107.0 | C35—C34—H34 | 120.2 |
C7—N1—H1A | 107.0 | C33—C34—H34 | 120.2 |
Ni1—N1—H1A | 107.0 | C29—C28—C27 | 119.9 (5) |
N4—C38—C30 | 123.9 (4) | C29—C28—H28 | 120.0 |
N4—C38—C37 | 116.9 (3) | C27—C28—H28 | 120.0 |
C30—C38—C37 | 119.2 (4) | C32—C31—C30 | 120.8 (5) |
N3—C37—C33 | 122.9 (4) | C32—C31—H31 | 119.6 |
N3—C37—C38 | 117.0 (4) | C30—C31—H31 | 119.6 |
C33—C37—C38 | 120.1 (4) | C4—C3—C2 | 120.2 (5) |
O1—C1—C2 | 122.4 (4) | C4—C3—H3 | 119.9 |
O1—C1—C6 | 116.9 (4) | C2—C3—H3 | 119.9 |
C2—C1—C6 | 120.7 (4) | C28—C29—C30 | 119.1 (4) |
O2—C20—C21 | 122.1 (4) | C28—C29—H29 | 120.4 |
O2—C20—C25 | 117.8 (4) | C30—C29—H29 | 120.4 |
C21—C20—C25 | 120.1 (4) | N4—C27—C28 | 122.7 (5) |
C20—C25—C24 | 118.8 (4) | N4—C27—H27 | 118.7 |
C20—C25—C26 | 120.6 (4) | C28—C27—H27 | 118.7 |
C24—C25—C26 | 120.5 (4) | N3—C36—C35 | 122.4 (5) |
C5—C6—C1 | 116.8 (4) | N3—C36—H36 | 118.8 |
C5—C6—C7 | 122.6 (4) | C35—C36—H36 | 118.8 |
C1—C6—C7 | 120.6 (4) | C11—C10—C12 | 110.8 (5) |
O6—C14—O5 | 123.7 (4) | C11—C10—C9 | 111.8 (5) |
O6—C14—C15 | 118.6 (4) | C12—C10—C9 | 111.5 (5) |
O5—C14—C15 | 117.6 (3) | C11—C10—H10 | 107.5 |
O3—C13—O4 | 124.6 (4) | C12—C10—H10 | 107.5 |
O3—C13—C8 | 118.0 (4) | C9—C10—H10 | 107.5 |
O4—C13—C8 | 117.3 (3) | C34—C35—C36 | 120.2 (5) |
C3—C2—C1 | 120.1 (5) | C34—C35—H35 | 119.9 |
C3—C2—H2B | 120.0 | C36—C35—H35 | 119.9 |
C1—C2—H2B | 120.0 | C10—C11—H11A | 109.5 |
C34—C33—C32 | 123.4 (5) | C10—C11—H11B | 109.5 |
C34—C33—C37 | 117.6 (5) | H11A—C11—H11B | 109.5 |
C32—C33—C37 | 118.9 (5) | C10—C11—H11C | 109.5 |
N1—C7—C6 | 115.1 (3) | H11A—C11—H11C | 109.5 |
N1—C7—H7A | 108.5 | H11B—C11—H11C | 109.5 |
C6—C7—H7A | 108.5 | C10—C12—H12A | 109.5 |
N1—C7—H7B | 108.5 | C10—C12—H12B | 109.5 |
C6—C7—H7B | 108.5 | H12A—C12—H12B | 109.5 |
H7A—C7—H7B | 107.5 | C10—C12—H12C | 109.5 |
C10—C9—C8 | 115.3 (4) | H12A—C12—H12C | 109.5 |
C10—C9—H9A | 108.4 | H12B—C12—H12C | 109.5 |
C8—C9—H9A | 108.4 | C19—C17—C16 | 105.2 (8) |
C10—C9—H9B | 108.4 | C19—C17—C18 | 112.8 (8) |
C8—C9—H9B | 108.4 | C16—C17—C18 | 108.8 (7) |
H9A—C9—H9B | 107.5 | C19—C17—H17 | 110.0 |
C38—C30—C29 | 116.9 (5) | C16—C17—H17 | 110.0 |
C38—C30—C31 | 119.4 (5) | C18—C17—H17 | 110.0 |
C29—C30—C31 | 123.7 (5) | C17—C19—H19A | 109.5 |
N1—C8—C13 | 110.0 (3) | C17—C19—H19B | 109.5 |
N1—C8—C9 | 112.6 (3) | H19A—C19—H19B | 109.5 |
C13—C8—C9 | 108.5 (3) | C17—C19—H19C | 109.5 |
N1—C8—H8 | 108.5 | H19A—C19—H19C | 109.5 |
C13—C8—H8 | 108.5 | H19B—C19—H19C | 109.5 |
C9—C8—H8 | 108.5 | C17—C18—H18A | 109.5 |
N2—C15—C16 | 112.9 (4) | C17—C18—H18B | 109.5 |
N2—C15—C14 | 110.4 (3) | H18A—C18—H18B | 109.5 |
C16—C15—C14 | 108.7 (4) | C17—C18—H18C | 109.5 |
N2—C15—H15 | 108.3 | H18A—C18—H18C | 109.5 |
C16—C15—H15 | 108.3 | H18B—C18—H18C | 109.5 |
C14—C15—H15 | 108.3 | ||
C27—N4—C38—C30 | −0.5 (7) | C26—N2—C15—C16 | 138.5 (4) |
Ni1—N4—C38—C30 | −179.2 (4) | Ni1—N2—C15—C16 | −90.4 (4) |
C27—N4—C38—C37 | 177.6 (5) | C26—N2—C15—C14 | −99.6 (4) |
Ni1—N4—C38—C37 | −1.2 (5) | Ni1—N2—C15—C14 | 31.5 (4) |
C36—N3—C37—C33 | −0.8 (7) | O6—C14—C15—N2 | 159.8 (3) |
Ni1—N3—C37—C33 | −179.5 (3) | O5—C14—C15—N2 | −23.3 (5) |
C36—N3—C37—C38 | 179.7 (4) | O6—C14—C15—C16 | −75.8 (5) |
Ni1—N3—C37—C38 | 0.9 (5) | O5—C14—C15—C16 | 101.1 (5) |
N4—C38—C37—N3 | 0.2 (7) | O2—C20—C21—C22 | 177.6 (5) |
C30—C38—C37—N3 | 178.3 (4) | C25—C20—C21—C22 | −1.6 (7) |
N4—C38—C37—C33 | −179.4 (4) | C20—C25—C24—C23 | −0.9 (6) |
C30—C38—C37—C33 | −1.2 (7) | C26—C25—C24—C23 | −176.4 (4) |
O2—C20—C25—C24 | −177.1 (4) | C1—C6—C5—C4 | −0.4 (6) |
C21—C20—C25—C24 | 2.1 (7) | C7—C6—C5—C4 | 179.0 (4) |
O2—C20—C25—C26 | −1.6 (6) | N2—C15—C16—C17 | −70.1 (6) |
C21—C20—C25—C26 | 177.6 (4) | C14—C15—C16—C17 | 167.1 (5) |
O1—C1—C6—C5 | 179.5 (4) | C6—C5—C4—C3 | 1.1 (7) |
C2—C1—C6—C5 | −1.1 (6) | C25—C24—C23—C22 | −0.8 (7) |
O1—C1—C6—C7 | 0.0 (5) | C24—C23—C22—C21 | 1.4 (8) |
C2—C1—C6—C7 | 179.5 (4) | C20—C21—C22—C23 | −0.2 (8) |
Ni1—O5—C14—O6 | 177.6 (3) | C34—C33—C32—C31 | −178.7 (5) |
Ni1—O5—C14—C15 | 0.9 (5) | C37—C33—C32—C31 | 0.8 (8) |
Ni1—O4—C13—O3 | −173.8 (3) | C15—N2—C26—C25 | −169.7 (3) |
Ni1—O4—C13—C8 | 9.4 (4) | Ni1—N2—C26—C25 | 66.6 (4) |
O1—C1—C2—C3 | −178.6 (4) | C20—C25—C26—N2 | 55.0 (6) |
C6—C1—C2—C3 | 2.0 (7) | C24—C25—C26—N2 | −129.5 (4) |
N3—C37—C33—C34 | 0.0 (7) | C32—C33—C34—C35 | 179.2 (5) |
C38—C37—C33—C34 | 179.6 (5) | C37—C33—C34—C35 | −0.3 (7) |
N3—C37—C33—C32 | −179.5 (4) | C33—C32—C31—C30 | −0.3 (8) |
C38—C37—C33—C32 | 0.0 (7) | C38—C30—C31—C32 | −0.9 (8) |
C8—N1—C7—C6 | −62.0 (5) | C29—C30—C31—C32 | 177.7 (6) |
Ni1—N1—C7—C6 | 174.2 (3) | C5—C4—C3—C2 | −0.1 (8) |
C5—C6—C7—N1 | 112.1 (4) | C1—C2—C3—C4 | −1.4 (7) |
C1—C6—C7—N1 | −68.5 (5) | C27—C28—C29—C30 | −1.7 (9) |
N4—C38—C30—C29 | 0.9 (7) | C38—C30—C29—C28 | 0.2 (8) |
C37—C38—C30—C29 | −177.1 (5) | C31—C30—C29—C28 | −178.5 (5) |
N4—C38—C30—C31 | 179.7 (5) | C38—N4—C27—C28 | −1.1 (8) |
C37—C38—C30—C31 | 1.7 (7) | Ni1—N4—C27—C28 | 177.4 (4) |
C7—N1—C8—C13 | −98.4 (4) | C29—C28—C27—N4 | 2.3 (9) |
Ni1—N1—C8—C13 | 30.0 (4) | C37—N3—C36—C35 | 1.8 (8) |
C7—N1—C8—C9 | 140.4 (4) | Ni1—N3—C36—C35 | −179.7 (4) |
Ni1—N1—C8—C9 | −91.2 (4) | C8—C9—C10—C11 | 167.2 (4) |
O3—C13—C8—N1 | 155.4 (4) | C8—C9—C10—C12 | −68.1 (6) |
O4—C13—C8—N1 | −27.6 (5) | C33—C34—C35—C36 | 1.3 (8) |
O3—C13—C8—C9 | −80.9 (5) | N3—C36—C35—C34 | −2.1 (9) |
O4—C13—C8—C9 | 96.1 (4) | C15—C16—C17—C19 | 159.5 (6) |
C10—C9—C8—N1 | −75.5 (5) | C15—C16—C17—C18 | −79.4 (7) |
C10—C9—C8—C13 | 162.4 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O6i | 0.82 | 1.82 | 2.597 (5) | 158 |
O1—H1···O3ii | 0.82 | 1.90 | 2.686 (5) | 161 |
N2—H2A···O2 | 0.98 | 2.13 | 2.856 (5) | 129 |
N1—H1A···O1 | 0.98 | 2.45 | 3.082 (5) | 122 |
C2—H2B···O3ii | 0.93 | 2.56 | 3.187 (6) | 125 |
C9—H9A···O5 | 0.97 | 2.38 | 3.212 (6) | 143 |
C16—H16B···O4 | 0.97 | 2.31 | 3.140 (7) | 143 |
C27—H27···O4 | 0.93 | 2.58 | 3.094 (5) | 116 |
C36—H36···O5 | 0.93 | 2.62 | 3.132 (6) | 115 |
Symmetry codes: (i) x−1/2, −y+3/2, −z+1; (ii) x+1/2, −y+1/2, −z+1. |
Bonds | X-ray | B3LYP/6–311G(d,p) |
Ni1—N3 | 2.101 (3) | 2.100 |
Ni1—N4 | 2.105 (3) | 2.105 |
Ni1—N1 | 2.141 (3) | 2.142 |
Ni1—N2 | 2.149 (3) | 2.149 |
Ni1—O5 | 2.044 (2) | 2.044 |
Ni1—O4 | 2.051 (3) | 2.051 |
O5—Ni1—O4 | 101.77 (11) | 101.771 |
N3—Ni1—N2 | 101.52 (15) | 101.51 |
Acknowledgements
The authors are grateful to the Ondokuz Mayıs University, Arts and Sciences Faculty, Department of Physics, Samsun, Turkey, for the X-ray data collection and Department of Chemistry, National Taras Shevchenko University of Kiev, for financial support.
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