Solvation, Hydration, and Counterion Effect on the Formation of Ag(I) Complexes with the Dipodal Ligand 2,6-Bis[(imidazol-2-yl)thiomethyl]naphthalene
Faculty of Chemistry, Nicolaus Copernicus University in Toruń, Gagarina 7, 87-100 Toruń, Poland
*
Author to whom correspondence should be addressed.
Crystals 2024, 14(3), 248; https://doi.org/10.3390/cryst14030248
Submission received: 28 January 2024
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Revised: 19 February 2024
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Accepted: 23 February 2024
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Published: 1 March 2024
(This article belongs to the Special Issue Research in Coordination Polymers)
Abstract
:A series of new Ag(I) complexes with 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene (L) and a range of counterions (X−) such as PF6− (1, 2), SbF6− (3), and CF3SO3− (4) was prepared. As shown by SCXRD studies, all of these are 1D coordination polymers with a waved chain motive and general formula {[AgL]X}n. Two methanol solvates containing PF6− (1) and SbF6− (3) counterions are isostructural. The triflate counterion leads to the formation of a topologically equivalent structural motive, with a different conformation of the ligand in the 1D chain and a different crystal packing as a result of the presence of another set of intermolecular interactions. The presence of water in 2 leads to a significant change in the conformation of the ligand. The naphthalene rings show a different orientation towards the imidazole rings, which is energetically less favorable but is stabilized by an extended net of intermolecular interactions with the counterion, which leads to an efficient crystal packing.
1. Introduction
For a couple of decades, researchers involved in crystal engineering have been collecting information on the effect of different factors on the crystallization outcome and the intermolecular interactions formed in order to be able to control the formation of crystalline products in a conscious way [1,2,3,4]. In this regard, crystal structure prediction methods (CSP), allowing for the prediction of crystal structures starting from the chemical components, have been developed [5,6]. These computational methods add valuable insight into the complex area of crystalline products but, for now, are still far from being routine practice [7]. It is fair to say that these are still in their infancy, but notable successes have already been achieved in certain cases, such as the prediction of polymorphs of organic molecules [8,9,10].
The possibility of designing crystals of particular structures and properties would be beneficial in many aspects of everyday life, especially in the pharmaceutical industry, where issues caused by the occurrence of polymorphs, hydrates, or solvates are encountered on a daily basis [1,11,12,13], as well as in materials science in general, as the appearance of an undesired crystalline form can completely change the properties of the particular material [1,3]. The presented study is a continuation of extensive research on factors influencing the outcome of the crystallization process [14,15,16,17]. It aims to reveal whether there are any preferences of new N-donor type bipodal ligands, such as 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene (L, Scheme 1), in the formation of crystal structures of metal complexes. Our previous work with related ligands containing a shorter spacer, namely a benzene ring as in 1,3-bis[(imidazol-2-yl)thiomethyl]benzene [15] and 1,2-bis[(imidazol-2-yl)thiomethyl]benzene [18] revealed their preference to form discrete silver complexes and a high affinity to form hydrates and solvates. Elongating the spacer by replacing benzene with naphthalene could lead to the preferential formation of species of higher dimensionality, but taking into account the high flexibility of the ligand, the outcome might be difficult to predict.
2. Materials and Methods
2.1. Reagents and Materials
All commercially available chemicals were of reagent grade and were used without further purification. The ligand, 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene was synthesized by SN2 reaction of 2-mercaptoimidazole (0.05 mol) with 2,6-bis(bromomethyl)naphthalene (0.01 mol) in MeOH. Both reactants were mixed in 100 mL of solvent and refluxed for 18 h. Then, the solvent was removed on a rotary evaporator, yielding a yellowish residue. Potassium carbonate (0.04 mol) dissolved in 150 mL of distilled water was added to the residue, and the resulting solution was stirred till a solid product was precipitated. The yellowish solid was then filtered off, washed with distilled water, and left to dry in the air. Yield: 41%.
1H NMR (DMSO-d6, 400 MHz, ppm) δ 7.72 (d, 2H), 7.64 (br s, 2H), 7.38 (dd, 2H), 7.07 (s, 4H), 4.38 (s, 4H); 13C NMR (DMSO-d6, 100 MHz, ppm) δ 137.4, 138.2, 135.6, 127.8, 127.4, 126.8, 123.9, 38.1.
2.2. Measurements
1H and 13C NMR spectra were recorded on a Bruker Avance III 400 MHz instrument and referenced to residual solvent peaks. PXRD analyses were performed on a Philips X’Pert diffractometer. The samples were measured in a 2θ range of 3–40°.
2.3. Synthesis of Ag(I) Complexes
The syntheses of the silver (I) complexes were performed in a dark environment. A solution of a particular silver salt (0.1 mmol) in methanol (10 mL) was added to a solution of 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene (0.1 mmol) in methanol (30 mL). The mixture was stirred for a few minutes and then left to undergo slow evaporation. After ca. 2 weeks, colorless crystals were obtained. The resulting products obtained in the reaction with AgPF6, AgSbF6, and AgCF3SO3 were washed and used for SCXRD, as well as for PXRD analyses.
2.4. Structure Determination
Single crystal X-ray diffraction data for L and 2 were collected on a SuperNova diffractometer equipped with MoKa radiation, λ = 0.71073 Å. Data for 1 and 3 were collected on a Bruker Apex II diffractometer equipped with graphite monochromated MoKα radiation (λ = 0.71073 Å), whereas data for 4 were collected on a Bruker Apex II diffractometer equipped with monochromated CuKα radiation (λ = 1.54178 Å). The crystals were mounted on a loop and coated with Paratone-N oil. Data collections were carried out at 100(2) K to minimize solvent loss, possible structural disorder, and thermal motion effects. Cell refinement and data reduction for 1, 3, and 4 were performed using the SAINT program [19], and all empirical absorption corrections were performed using SADABS [20]. Data frames for L and 2 were processed (unit cell determination, intensity data integration, correction for Lorentz and polarization effects, and empirical absorption correction) using the corresponding diffractometer’s software package [21]. Each structure was solved by direct methods using SHELXS-2018/3 [22] and refined by full-matrix least-squares methods based on F2 using SHELXL-2018/3 [23]. The programs MERCURY [24] and POV-Ray [25] were used to prepare the molecular graphics images. All non-hydrogen atoms were refined anisotropically, and all hydrogen atoms, except the OH (methanol) in 1/3 and water hydrogen atoms in 2, were positioned geometrically with C-H = 0.95 (aromatic), 0.99 (methylene), N-H = 0.88 Å, refined as riding, with Uiso(H) = 1.2 Ueq (C,N). The H(O) atoms of complexes 1–3 were located from Fourier difference maps and modeled in the case of 3 with distance and angular restraints. Compound 4 was solved as an inversion twin. The twin ratio refines to 0.52:0.48. The counterion in compound 2 has been found disordered over two orientations, which were modeled with equal occupancies.
A summary of the data collection and structure refinement parameters is provided in Table 1. The crystallographic data for compounds L, 1–4 have been deposited at the Cambridge Crystallographic Data Centre: CCDC 2328284-2328288 for L, 1–4, respectively. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via http://www.ccdc.cam.ac.uk/structures (accessed on 1 February 2024).
The level B alert present in the CheckCIF of 2 is a result of the presence of heavy metal, around which the electron density is spread with the highest peak amounting to 0.9 eÅ−3.
2.5. Computational Study
Geometry optimizations were performed to investigate the conformational preferences of the ligand. Ligand structures extracted from crystal structures of L and 1–4 were used as the starting geometry for the calculations. Computations were performed using the B3LYP DFT functional, including Grimme’s dispersion correction (GD3) with Becke–Johnson damping [26] and the 6–31G(d,p) basis set using the Gaussian16 package [27].
3. Results and Discussion
As mentioned before, the performed study is a continuation of more extensive studies on the structural preferences in the formation of metal complexes by N-donor dipodal ligands. Recently, we showed that lowering the flexibility of a particular dipodal ligand, achieved by introducing a higher number of methyl substituents, facilitates the syn conformation of the ligand and the formation of discrete metal complexes in the solid state. [14]. Here, the effect of elongating a selected ligand’s spacer was studied to check the preferences of this molecule toward the formation of metal complexes of a particular dimensionality.
3.1. Crystal Structure of L
The new ligand 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene crystallizes in a centrosymmetric space group of a triclinic system with two crystallographically independent halves of the molecules in the asymmetric unit (Figure 1).
Both molecules show the same conformation with an RMSD of 0.053 Å. They interact together by strong N-H···N hydrogen bonds such as N3-H3···N13 (N-N distance of 2.818(3) Å, N-H-N angle of 179°) and N15-H15···N1i (N-N distance of 2.835(3) Å, N-H-N angle of 176°, symmetry operator ((i): x, y + 1, z) forming supramolecular 1D strands extending along the b-axis. The imidazole rings in the single molecule are parallel to each other. The dihedral angles C2-S6-C7-C8 and the corresponding one in the other molecule (C14-S18-C19-C20) are equal to 63° (Table 2).
3.2. Crystal Structures of {[AgL](PF6)}n·nMeOH (1), {[AgL](PF6)}n·n(0.5H2O) (2), and {[AgL](SbF6)}n·nMeOH (3)
The methanol solvate (1) and the hydrate (2) of {[AgL](PF6)}n crystallize in different crystallographic systems, namely an orthorhombic or a monoclinic system of a Pnma or P2/c space group, respectively. Both compounds (Figure 2) show the presence of half of the ligand molecules, silver ions located in special positions (Ag ions located on inversion centers), counterion and methanol or water molecules located in special positions (mirror plane (1) or 2-fold axis (2)) in the asymmetric unit. The complexes form 1D cationic polymers, in which the Ag ions are coordinated by the N-atoms originating from two symmetry-related molecules of the ligand with an ideal linear geometry (N-Ag-N angle of 180°) (Table 3).
The formed waved chains expand along the c-axis in 1 and the a-axis in 2. Both imidazole rings in the single ligand are oriented towards the naphthalene moiety and are parallel to each other. The dihedral angles C2-S6-C7-C8 differ by 19° (Table 2), indicating the changes in ligand conformation. The values of the dihedral angles C2-S6-C8-C12 indicate a different orientation of the imidazole rings towards the naphthalene spacer, which could be easily overlooked. This is an effect of the rotation of the naphthalene ring, which is stabilized by a net of hydrogen bonds in the other position (Figure 3).
The packings of both metal complexes are very different, even though they are stabilized by similar sets of hydrogen bonds (Table 4, Figure S1).
Interestingly, the counterions and methanol molecules in 1 form layers in the ac plane (Figure 4), connected by a net of hydrogen bonds, such as O-H∙∙∙F and C-H∙∙∙F, and interact further with the layers of metal complexes, which consist of columns of 1D chains, via N-H∙∙∙O and C-H∙∙∙F hydrogen bonds. These A,B layers of metal complexes show an alternating orientation in each adjacent layer. In 2, the counterions and water molecules form supramolecular chains via O-H∙∙∙F hydrogen bonds extending along the a-axis, which are further interacting with 1D cationic polymers via N-H∙∙∙O, N-H∙∙∙F, and C-H∙∙∙F (Table 4). The cationic chains are expanding along the same axis and are stacked above each other. Also, in this case, the presence of A,B type of layers of the cationic complex can be observed.
The methanol solvate 3, which contains a counterion that is slightly bigger than PF6− but of the same geometry, namely SbF6− (3), Figure S2, is isostructural with compound 1, with isostructurality and cell similarity indices of 74.9% and an overlay of the monomeric cationic unit with RMSD of 0.041 Å (Figure 3) [29,30].
3.3. Crystal Structure of {[AgL](CF3SO3)}n (4)
The isolated crystal structure of the silver complex with the triflate counterion crystallizes in a monoclinic system of the Cc space group with one molecule of the ligand, one Ag cation, and one counterion in the asymmetric unit (Figure 5).
The silver ions are coordinated by N-atoms originating from two symmetry-related ligands showing an almost ideal linear geometry (Table 3) and yielding once again 1D waved chains extending along the [1 1 0] direction. The ligand conformation reminds more of the one adopted by the free ligand or by the ligand in 1 and 3 than in 2 (Figure 6). The angle between the planes of the imidazole rings is 11°. The dihedral angles C2-S6-C7-C8 and C20-S19-C18-C13 are 52.1(6)/−53.1(7)°, respectively, and the angles corresponding to C2-S6-C8-C12 in 1 are −20.1(6)/17.4(6)° (Table 2).
The counterions interact strongly with the metal complex by a net of hydrogen bonds, but we could indicate once again the A, B layers formed by columns of 1D chains stacked above each other and separated by counterions.
3.4. Ligand Flexibility
As presented above, the connectivity between the aromatic spacer and the imidazole ring gives the ligand much flexibility. We wondered whether the conformation adopted by the ligand in 2 had been caused by the presence of a water molecule or whether it was just kind of a polymorphic outcome. To gain some more insight into this matter, we performed geometry optimizations in the gas phase. Optimizing the ligand structures from 1, 3, 4, and L resulted in the same geometry, while 2 exhibited distinct features (Table 5).
The calculated energies of both forms revealed that the optimized ligand structures from 1, 3, 4, and L exhibit higher stability compared to that of 2 by 6.5 kJ/mol.
This could indicate that the water molecules, which are smaller than the methanol molecules, are responsible for the rearrangement of the packing and the occurrence of a less favorable conformation of the ligand. Comparing the data obtained from PXRD studies collected for solids obtained from reactions with PF6−, SbF6−, and CF3SO3− indicates some additions of other phases in all cases (Figures S3–S5). We were only able to isolate single crystals of different forms from the vial with PF6−. However, hydrates, solvates, and polymorphs could be present in all vials.
4. Conclusions
The performed studies revealed that the bipodal ligand 2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene shows preference to form 1D coordination polymers, unlike compounds with related ligands containing a shorter spacer, namely 1,3-bis [(imidazol-2-yl)thiomethyl]benzene or 1,2-bis [(imidazol-2-yl)thiomethyl]benzene, which show a tendency to form discrete species. Moreover, as also noticed for earlier studied related compounds, as a result of the presence of an amine N-atom, the ligand shows a high affinity for the formation of solvates and hydrates. Furthermore, even though the formed metal complexes show a similar topology, the ligand adopts different conformations, which is especially striking in the case of two isolated compounds with hexafluorophosphate, such as the methanol solvate and the hydrate. The ligand in the latter adopts an energetically less favorable conformation, which seems to be stabilized in the crystal by an extended net of intermolecular interactions with the counterion. The presence of different crystalline forms is not noticeable in bulk and would not be perceived without performing PXRD studies, which are essential for materials containing a range of heteroatoms in the formula, especially if the solids are set to be further studied toward particular applications.
Supplementary Materials
The following supporting information can be downloaded at https://www.mdpi.com/article/10.3390/cryst14030248/s1. Figure S1: Packing diagram for 1 shown down the c-axis (on the left) and for 2 shown down the b-axis (on the right), the space where the counterion and solvent molecules are located is indicated in pink. Figure S2: Monomeric unit of the cationic 1D chain, counterion, and methanol molecule in 3, N-H···O and O-H···F hydrogen bonds indicated in pink and red, correspondingly; displacement ellipsoids drawn at the 50% probability level. Figure S3: Result of PXRD analyses for solid obtained in reaction with AgPF6; red—calculated for 1, blue—calculated for 2, black—experimental one for bulk material. Figure S4: Result of PXRD analyses for solid obtained in reaction with AgSbF6; red—calculated for 3, black—experimental one for bulk material. Figure S5: Result of PXRD analyses for solid obtained in reaction with AgCF3SO3; red—calculated for 4, black—experimental one for bulk material.
Author Contributions
Conceptualization, L.D.; methodology, L.D.; software, L.D., R.M.L. and S.C; investigation, L.D. and R.M.L.; writing—original draft preparation, L.D.; editing, R.M.L. and S.C.; visualization, L.D. and R.M.L. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by the National Science Centre—Poland, grant number 2014/14/E/ST5/00611.
Data Availability Statement
Data are contained within the article.
Acknowledgments
R.M.L., S.C. and L.D. would like to thank the ‘Excellence Initiative—Research University’ program for funding the research group of Crystal Engineering and Advanced Solid-State Characterization.
Conflicts of Interest
The author declares no conflicts of interest. The funders had no role in the design of the study, in the collection, analyses, or interpretation of data, in the writing of the manuscript, or in the decision to publish the results.
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Scheme 1.
2,6-bis[(imidazol-2-yl)thiomethyl]naphthalene (L).
Figure 1.
On the left: representation of two molecules of the ligand, two halves of which are present in the asymmetric unit, and the other halves are generated by the symmetry operations 2 − x, −y, −z for the molecule containing N1, and 2 − x, 1 − y, − z for the molecule containing N13, with displacement ellipsoids drawn at the 50% probability level. On the right: fragment of a 1D supramolecular strand formed by strong N-H···N hydrogen bonds (indicated in blue).
Figure 1.
On the left: representation of two molecules of the ligand, two halves of which are present in the asymmetric unit, and the other halves are generated by the symmetry operations 2 − x, −y, −z for the molecule containing N1, and 2 − x, 1 − y, − z for the molecule containing N13, with displacement ellipsoids drawn at the 50% probability level. On the right: fragment of a 1D supramolecular strand formed by strong N-H···N hydrogen bonds (indicated in blue).
Figure 2.
Top row: representation of a monomeric unit of the cationic 1D chain, counterion, and methanol molecule in 1 or water molecule in 2; selected hydrogen bonds such as C-H···F, N-H···O, N-H···F and O-H···F are shown as dashed lines in blue, pink, green and red, respectively; the labeled atoms represent the constituents of the asymmetric unit; displacement ellipsoids drawn at the 50% probability level. Bottom row: fragments of the cationic chains expanding along the c-axis in 1 and the a-axis in 2, respectively.
Figure 2.
Top row: representation of a monomeric unit of the cationic 1D chain, counterion, and methanol molecule in 1 or water molecule in 2; selected hydrogen bonds such as C-H···F, N-H···O, N-H···F and O-H···F are shown as dashed lines in blue, pink, green and red, respectively; the labeled atoms represent the constituents of the asymmetric unit; displacement ellipsoids drawn at the 50% probability level. Bottom row: fragments of the cationic chains expanding along the c-axis in 1 and the a-axis in 2, respectively.
Figure 3.
Overlays of fragments of the 1D chains, on the left in 1 (red) and 2 (blue), RMSD = 1.417 Å; on the right in 1 (red) and 3 (green), RMSD = 0.041 Å.
Figure 3.
Overlays of fragments of the 1D chains, on the left in 1 (red) and 2 (blue), RMSD = 1.417 Å; on the right in 1 (red) and 3 (green), RMSD = 0.041 Å.
Figure 4.
On the left: fragment of the 2D net of interacting counterions and methanol molecules in the ac plane in 1, stabilized via O-H∙∙∙F (red) and C-H∙∙∙F (blue) hydrogen bonds. On the right: supramolecular 1D chains of alternating counterions and water molecules, in 2 held together via O-H∙∙∙F (red) hydrogen bonds and expanding along the a-axis; disorder (MeOH in 1, counterion in 2) not shown for clarity.
Figure 4.
On the left: fragment of the 2D net of interacting counterions and methanol molecules in the ac plane in 1, stabilized via O-H∙∙∙F (red) and C-H∙∙∙F (blue) hydrogen bonds. On the right: supramolecular 1D chains of alternating counterions and water molecules, in 2 held together via O-H∙∙∙F (red) hydrogen bonds and expanding along the a-axis; disorder (MeOH in 1, counterion in 2) not shown for clarity.
Figure 5.
On the left: asymmetric unit in 4, displacement ellipsoids drawn at the 50% probability level. On the right: fragment of the cationic chain present in 4.
Figure 5.
On the left: asymmetric unit in 4, displacement ellipsoids drawn at the 50% probability level. On the right: fragment of the cationic chain present in 4.
Figure 6.
Overlays of fragments of the 1D chains. On the left: 4 (yellow) and 1 (red), RMSD = 0.835 Å. On the right: 4 (yellow) and 2 (blue), RMSD = 1.613 Å.
Figure 6.
Overlays of fragments of the 1D chains. On the left: 4 (yellow) and 1 (red), RMSD = 0.835 Å. On the right: 4 (yellow) and 2 (blue), RMSD = 1.613 Å.
Table 1.
Crystal data and details of the refinement parameters for the crystal structures L and 1–4.
Table 1.
Crystal data and details of the refinement parameters for the crystal structures L and 1–4.
| Compound Reference | L | 1 | 2 | 3 | 4 |
|---|---|---|---|---|---|
| Chemical formula | C18H16N4S2 | C19H20AgF6N4OPS2 | C18H17AgF6N4O0.50PS2 | C19H20AgF6N4OS2Sb | C19H16AgF3N4O3S3 |
| Moiety formula | C18H16N4S2 | C18H16N4S2, PF6, CH3OH | C18H16N4S2, PF6, 0.5H2O | C18H16N4S2, SbF6, CH3OH | C18H16N4S2, CF3SO3 |
| Formula mass | 352.47 | 637.35 | 614.32 | 728.13 | 609.41 |
| Crystal system | triclinic | orthorhombic | monoclinic | orthorhombic | monoclinic |
| Space group | P | Pnma | P2/c | Pnma | Cc |
| a/Å | 7.8283(7) | 12.9946(16) | 7.0262(3) | 13.2518(11) | 10.2357(4) |
| b/Å | 9.6245(9) | 25.731(3) | 7.1038(3) | 25.931(2) | 10.5422(5) |
| c/Å | 12.5835(9) | 6.8789(8) | 22.0691(10) | 6.9009(6) | 21.5516(8) |
| α/° | 83.293(6) | 90 | 90 | 90 | 90 |
| β/° | 78.145(7) | 90 | 92.951(4) | 90 | 90.838(2) |
| γ/° | 71.301(8) | 90 | 90 | 90 | 90 |
| Unit cell volume/Å3 | 877.56(14) | 2300.1(5) | 1100.07(8) | 2371.4(3) | 2325.32(17) |
| Temperature/K | 289(3) | 100(2) | 100(2) | 100(2) | 100(2) |
| No. of formula units per unit cell, Z | 2 | 4 | 2 | 4 | 4 |
| Radiation type | MoKα | MoKα | MoKα | MoKα | CuKα |
| Absorption coefficient, μ/mm−1 | 0.310 | 1.197 | 1.246 | 2.209 | 9.965 |
| No. of reflections measured | 18417 | 13577 | 5655 | 13539 | 11139 |
| No. of independent reflections | 4948 | 2816 | 2990 | 2903 | 4180 |
| Rint | 0.0437 | 0.0847 | 0.0413 | 0.0380 | 0.0708 |
| Final R1 values (I > 2σ(I)) | 0.0520 | 0.0548 | 0.0564 | 0.0291 | 0.0410 |
| Final wR(F2) values (I > 2σ(I)) | 0.0895 | 0.1081 | 0.1172 | 0.0657 | 0.0936 |
| Final R1 values (all data) | 0.1006 | 0.0977 | 0.0959 | 0.0342 | 0.0432 |
| Final wR(F2) values (all data) | 0.1075 | 0.1240 | 0.1442 | 0.0675 | 0.0948 |
| Goodness of fit on F2 | 1.041 | 1.025 | 1.046 | 1.060 | 1.044 |
Table 2.
Geometrical parameters of the ligand, highlighting its flexibility.
| L | 1 | 2 | 3 | 4 | |
|---|---|---|---|---|---|
| Torsion angle (°) C2-S6-C7-C8 (and corresponding ones) | 63.3(2) 62.8(2) | 76.0(4) | 57.0(5) | 74.6(2) | 52.1(6)/−53.1(7) |
| Distance between centroids of imidazole rings (Å) | 9.91/9.84 | 10.78 | 10.45 | 10.72 | 8.66 |
| Dihedral angle between the planes of the imidazole rings (°) | 0 | 0 | 0 | 0 | 10.8(7) |
| Dihedral angle between the planes of the imidazole and naphthalene ring | 45.4(1) 44.5(1) | 25.5(2) | 27.2(2) | 25.8(1) | 32.9(4)/22.2(4) |
| Dihedral angle C2-S6-C8-C12 (and corresponding ones) | 7.6(2) 6.1(2) | 0.4(4) | 121.5(5) | 2.0(2) | −20.1(6)/17.4(6) |
Table 3.
Selected bond distances (Å) and angles (°) for the presented silver complexes.
| Complex | Ag1-N1 Bond Length (Å) | N1-Ag1-N1i Angle (°) |
|---|---|---|
| 1 | 2.107(4) | 180 |
| 2 | 2.099(4) | 180 |
| 3 | 2.103(2) | 180 |
| 4 | 2.124(10) | 178.8(4) |
| 2.107(10) (N1i) |
Symmetry transformations used to generate equivalent atoms: (1) (i) 1 − x, 1 − y, 1 − z; (2) (i) 1 − x, 1 − y, 1 − z; (3) (i) 2 − x, −y, z; (4) (i) −1/2 + x, −1/2 + y, z.
Table 4.
Selected hydrogen bonds in the presented silver complexes [28].
Table 4.
Selected hydrogen bonds in the presented silver complexes [28].
| D-H···A | H···A (Å) | D···A (Å) | D-H···A (°) | D-H···A | H···A (Å) | D···A (Å) | D-H···A (°) | ||
|---|---|---|---|---|---|---|---|---|---|
| 1 | N3-H3···O20 | 1.94 | 2.801(5) | 164 | 3 | N3-H3···O20 | 1.93 | 2.792(3) | 167 |
| O20-H20···F15i | 2.11 | 2.897(7) | 161 | O20-H20···F15 | 1.98 | 2.820(4) | 172 | ||
| O20-H20···F17ii | 2.81 | 3.195(7) | 111 | O20-H20···F17i | 2.62 | 2.966(4) | 107 | ||
| C4-H4∙∙∙F16 | 2.69 | 3.245(5) | 118 | C4-H4∙∙∙F16ii | 2.70 | 3.208(3) | 114 | ||
| C7-H7A∙∙∙F14iii | 2.77 | 3.53(6) | 134 | C7-H7A∙∙∙F14iii | 2.68 | 3.467(3) | 137 | ||
| C7-H7B∙∙∙F14ii | 2.82 | 3.72(6) | 152 | C7-H7B∙∙∙F14i | 2.89 | 2.743(3) | 145 | ||
| C7-H7B∙∙∙F17ii | 2.69 | 3.629(5) | 158 | C7-H7B∙∙∙F17i | 2.70 | 3.619(3) | 154 | ||
| C12-H12···F14ii | 2.67 | 3.552(6) | 155 | C12-H12∙∙∙F14i | 2.48 | 3.394(3) | 162 | ||
| C19-H19A∙∙∙F16i | 2.95 | 3.668(9) | 131 | C19-H19A∙∙∙F1 | 2.87 | 3.614(6) | 134 | ||
| C19-H19B∙∙∙F16 | 2.95 | 3.547(9) | 120 | C19-H19B∙∙∙F16ii | 2.95 | 3.478(5) | 115 | ||
| C19-H19B···F17 | 2.66 | 3.500(9) | 144 | C19-H19B···F17ii | 2.62 | 3.490(5) | 148 | ||
| C19-H19A∙∙∙F18iv | 2.59 | 3.081(9) | 111 | C19-H19A∙∙∙F18iv | 2.61 | 3.064(5) | 108 * | ||
| 2 | N3-H3∙∙∙O18 | 2.20 | 2.97(1) | 146 | 4 | N3-H3∙∙∙O30 | 2.08 | 2.83(1) | 142 |
| N3-H3∙∙∙F4i | 2.52 | 3.07(2) | 121 | C7-H7B∙∙∙O30 | 2.63 | 3.50(1) | 147 | ||
| N3-H3∙∙∙F5 | 2.21 | 3.06(2) | 159 | C23-H23∙∙∙O30i | 2.50 | 3.35(1) | 150 | ||
| N3-H3∙∙∙F15i | 2.22 | 2.92(1) | 136 | C18-H18A∙∙∙O31ii | 2.77 | 3.55(1) | 136 | ||
| N3-H3∙∙∙F16 | 2.35 | 2.93(2) | 124 | C22-H22∙∙∙O31i | 2.70 | 3.40(1) | 131 | ||
| O18-H18A∙∙∙F2 | 2.67 | 3.49(2) | 141 | N24-H24∙∙∙O31iii | 1.99 | 2.80(1) | 153 | ||
| O18-H18A∙∙∙F3i | 1.66 | 2.50(3) | 140 | C14-H14∙∙∙O32iv | 2.65 | 3.38(1) | 134 | ||
| O18-H18A∙∙∙F14 | 2.03 | 2.89(1) | 145 | C12-H12∙∙∙F26ii | 2.79 | 3.73(1) | 170 | ||
| C4-H4∙∙∙F2ii | 2.37 | 3.08(2) | 132 | C9-H9∙∙∙F27i | 2.90 | 3.46(1) | 118 | ||
| C4-H4∙∙∙F3iii | 2.63 | 3.37(2) | 135 | C10-H10∙∙∙F27i | 2.80 | 3.40(1) | 122 | ||
| C4-H4∙∙∙F14iv | 2.38 | 3.150(1) | 138 | C15-H15∙∙∙F28 | 2.96 | 3.80(1) | 149 | ||
| C7-H7B∙∙∙F5iv | 2.60 | 3.58(2) | 172 | C17-H17∙∙∙F28 | 2.72 | 3.63(1) | 159 | ||
| C7-H7B∙∙∙F15v | 2.50 | 3.45(1) | 160 | C7-H7A∙∙∙Cg4v | 2.83 | 3.562(9) | 131 | ||
| C10-H10∙∙∙F1vi | 2.67 | 3.61(2) | 171 |
Symmetry transformations used to generate equivalent positions: (1) (i) 1/2 + x, 3/2 − y, 1/2 − z, (ii) x, y, 1 + z, (iii) 1/2 + x, y, 1/2 − z, (iv) 1/2 + x, 3/2 − y, −z − 1/2; (2) (i) 2 − x, y, 3/2 − z, (ii) x, 1 + y, z, (iii) 2 − x, 1 + y, 3/2 − z, (iv) 1 − x, y, 3/2 − z, (v) −1 + x, y, z, (vi) x − 1, 1 + y, z; (3) (i) x − 1/2, 1/2 − y, −z + 1/2, (ii) x − 1/2, 1/2 − y, −z − 1/2 (iii) x, 1/2 − y, z, (iv) x, y, −1 + z; (4) (i) x, 1 − y, 1/2 + z, (ii) x − 1/2, 3/2 − y, 1/2 + z, (iii) −1/2 + x, 3/2 − y, 1/2 + z, (iv) x − 1/2, 1/2 + y, z, (v) 1/2 + x, −1/2 + y, z. Cg4 for 4 is the centroid of one of the rings in the naphthalene moiety (C11–C16). * This value is provided for comparison with the corresponding distances/angles in 1.
Table 5.
Values of the dihedral angle C2-S6-C8-C12 (and corresponding angles) in the structures obtained from the CIF files and after optimizing the geometries.
Table 5.
Values of the dihedral angle C2-S6-C8-C12 (and corresponding angles) in the structures obtained from the CIF files and after optimizing the geometries.
| L | L-opt | 1 | 1-opt | 2 | 2-opt | 3 | 3-opt | 4 | 4-opt | |
|---|---|---|---|---|---|---|---|---|---|---|
| Dihedral angle (°) C2-S6-C8-C12 (and corresponding ones) | 6.1(2) | 30.6 | 0.4(4) | 31.1 | 121.5(5) | 123.5 | 2.0(2) | 31.1 | −20.1(6)/ 17.4(6) | −30.6/ 30.6 |
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Maria Losus, R.; Chaudhary, S.; Dobrzańska, L. Solvation, Hydration, and Counterion Effect on the Formation of Ag(I) Complexes with the Dipodal Ligand 2,6-Bis[(imidazol-2-yl)thiomethyl]naphthalene. Crystals 2024, 14, 248. https://doi.org/10.3390/cryst14030248
AMA Style
Maria Losus R, Chaudhary S, Dobrzańska L. Solvation, Hydration, and Counterion Effect on the Formation of Ag(I) Complexes with the Dipodal Ligand 2,6-Bis[(imidazol-2-yl)thiomethyl]naphthalene. Crystals. 2024; 14(3):248. https://doi.org/10.3390/cryst14030248
Chicago/Turabian StyleMaria Losus, Renny, Simran Chaudhary, and Liliana Dobrzańska. 2024. "Solvation, Hydration, and Counterion Effect on the Formation of Ag(I) Complexes with the Dipodal Ligand 2,6-Bis[(imidazol-2-yl)thiomethyl]naphthalene" Crystals 14, no. 3: 248. https://doi.org/10.3390/cryst14030248
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