research communications
Di-n-butyl[N′-(3-methoxy-2-oxidobenzylidene)-N-phenylcarbamohydrazonothioato]tin(IV): Hirshfeld surface analysis and computational study
aChemistry Section, School of Distance Education, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia, bDepartment of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM Serdang 43400, Malaysia, cResearch Centre for Crystalline Materials, School of Medical and Life Sciences, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia, dCentre for Drug Research, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang, Malaysia, eSchool of Chemical Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia, and fFoundry of Reticular Materials for Sustainability (FORMS), Materials Synthesis and Characterization Laboratory, Institute of Advanced Technology, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul, Ehsan, Malaysia
*Correspondence e-mail: edwardt@sunway.edu.my
The title diorganotin Schiff base derivative, [Sn(C4H9)2(C15H13N3O2S)], features a penta-coordinated tin centre defined by the N,O,S-donor atoms of the di-anionic Schiff base ligand and two methylene-C atoms of the n-butyl substituents. The resultant C2NOS donor set defines a geometry intermediate between trigonal–bipyramidal and square-pyramidal. In the crystal, amine-N—H⋯O(methoxy) hydrogen bonding is found in a helical, supramolecular chain propagating along the b-axis direction. The chains are assembled into a layer parallel to (01) with methylene-C—H⋯π(phenyl) interactions prominent; layers stack without directional interactions between them. The analysis of the calculated Hirshfeld surface showed the presence of weak methylene-C—H⋯π(phenyl) interactions and short H⋯H contacts in the inter-layer region. Consistent with the nature of the identified contacts, the stabilization of the crystal is dominated by the dispersion energy term.
Keywords: crystal structure; organotin; Schiff base; thiosemicarbazone; hydrogen bonding; Hirshfeld surface analysis.
CCDC reference: 2063179
1. Chemical context
Thiosemicarbazones are an important class of compounds that have received wide attention due to their many biological and pharmacological properties, such as anti-bacterial, anti-viral, anti-neoplastic and anti-malarial activities (Kovala-Demerzi et al., 1997; Hu et al., 2006; Khan & Yusuf, 2009). Thiosemicarbazone are similar to their dithiocarbazate counterparts in that complexation with a metal centre is achieved via the nitrogen and sulfur atoms following deprotonation of the S—H and N—H groups (Đilović et al., 2008; Wiecek et al., 2009; Pavan et al., 2010; Parrilha et al., 2011; Singh et al., 2016; Palanimuthu et al., 2017). Tin(IV) compounds of 3-methoxysalicylaldehyde thiosemicarbazone have been evaluated for their in vitro cytotoxicity against a line of human T lymphocyte cells, Jurkat cells (Khandani et al., 2013): in this study, a structure–activity analysis for the dialkyltin(IV) compounds indicated that cytotoxicity increased with the length of the alkyl carbon chain of the tin-bound substituents. Thus, the cytotoxicity was in the order of dibutyl > diphenyl > dimethyl (Khandani et al., 2013). The ability of the 2-acetylpyridine N(4)-cyclohexylthiosemicarbazone Schiff base (LH2) and its distorted pentagonal bipyramidal tin(IV) compound, [Ph2Sn(L)(OAc)]·EtOH, to inhibit tumour cell growth against HepG2 cells has also been reported (Liu et al., 2017). This study showed the tin(IV) compound to exhibit threefold higher cytotoxic potency compared to the free ligand, i.e. with IC50 values of 3.32±0.52 and 10.10±2.07 µM, respectively, and to be more potent than the reference drug mitoxantone (IC50 = 5.3±2.38 µM). Significant activity was also observed in an in vitro cytotoxic assay of tin(IV) compounds of 2-hydroxy-5-methoxybenzaldehyde-N(4)-methylthiosemicarbazone (Salam et al., 2016), diphenyltin(IV) compounds of 2-benzoylpyridine N(4)-phenyl thiosemicarbazone and 2-acetylpyrazine N(4)-phenylthiosemicarbazone (Li et al., 2011) in comparison to the standard drugs used. It may be concluded that the coordination of the Schiff base ligand to the tin(IV) centre enhanced cytotoxic activity, where the reported IC50 values were better than standard drugs.
Further, the enhancement of cytotoxicity in the diphenyltin derivatives has been attributed to the presence of these phenyl groups, which suggested interactions between the tin-bound phenyl groups with intra-cellular biomacromolecules. An independent biological study suggested that the diffusion, lipophilic character and steric effects associated with the ligand could also be factors in determining cytotoxic activity (Salam et al., 2016). The improvement of cytotoxic activity was also suggested to be due to the presence of OH/NH groups, which enabled hydrogen bonding with DNA base pairs (Haque et al., 2015). As part of our on-going studies in the structural elucidation and cytotoxic activity of tin(IV) compounds containing thiosemicarbazones Schiff base (Yusof et al., 2020), herein are described the synthesis of the title dibutyltin(IV) derivative, (I), its single crystal X-ray and a detailed study of supramolecular association by an analysis of the calculated Hirshfeld surfaces and computational chemistry.
2. Structural commentary
The molecular structure of (I), Sn(C15H13N3O2S)(C4H9)2 (Fig. 1), comprises a five-coordinate tin centre, being coordinated by a tridentate Schiff base di-anion and two n-butyl groups leading to a C2NOS donor set. Selected geometric parameters for (I) are collated in Table 1. While the direct acid analogue for the Schiff base in (I) has yet to be characterized crystallographically, the 4-methoxy analogue is known (Rubčić et al., 2008). Compared to the S1—C1 [1.747 (3) Å], C1—N1 [1.304 (3) Å] and C2—N2 [1.311 (3) Å] bond lengths in (I), the equivalent bonds in the acid are 1.6769 (14), 1.3441 (17) and 1.2798 (18) Å, respectively (Spek, 2020), consistent with elongation, shortening and elongation in (I), respectively, confirming the presence of the thiolate-S1 and imine-N1 atoms. The angles subtended at the tin centre, Table 1, indicate a highly distorted coordination geometry. The angle closest to a trans angle is 157.56 (5)°, for S1—Sn—O1, with the next two widest angles being N2—Sn—C16 [126.42 (9)°] and C16—Sn—C20 [124.08 (11)°]. The distortion from the ideal square-pyramidal and trigonal-bipyramidal geometries is quantified by the value of τ, with values of 0.0 and 1.0, respectively (Addison et al., 1984). For (I), this computes to 0.52, being almost exactly between the two extreme values.
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The N,O,S mode of coordination of the Schiff base di-anion gives rise to the formation of five- and six-membered chelate rings, the acute chelate angles, Table 1; these are partly responsible for the observed distortions in the coordination environment. The former ring, comprising the Sn, S1, N1, N2 and C1 atoms is almost planar, presenting a r.m.s. deviation of 0.0087 Å: atom N3 lies 0.016 (3) Å out of this plane. By contrast, distortions are evident in the six-membered chelate ring, defined by the Sn, O1, N2, C2–C4 atoms. The simplest description for the conformation is that of an envelope with the tin atom lying 0.519 (3) Å out of the plane defined by the remaining five atoms (r.m.s. deviation = 0.0379 Å). The dihedral angle between the five-membered chelate ring and the best plane through the five approximately co-planar atoms of the six-membered chelate ring is 13.59 (12)°, that between the five-membered and N-bound phenyl ring is 6.92 (12)° and that between the peripheral C6 rings is 19.63 (13)°, highlighting the observation the Schiff base di-anion deviates significantly from co-planarity.
3. Supramolecular features
Conventional hydrogen bonding is noted in the crystal of (I), Table 2. Thus, amine-N—H⋯O(methoxy) hydrogen bonds assemble molecules into a helical, supramolecular chain propagating along the b-axis direction, Fig. 2(a). The only other directional interactions based on an analysis of the points of contact between molecules in the crystal (Spek, 2020), are methylene-C—H⋯π(phenyl) interactions. These lead to a supramolecular layer parallel to (01), Fig. 2(b). Layers stack without specific interactions between them, Fig. 2(c).
4. Analysis of the Hirshfeld surfaces
The Hirshfeld surface analysis for (I) was conducted to ascertain further information on the supramolecular association between molecules in the crystal, in particular in the inter-layer region. The calculated Hirshfeld surface was mapped over the normalized contact distance dnorm (McKinnon et al., 2004) and electrostatic potential (Spackman et al., 2008), and the associated two-dimensional fingerprint plots were calculated using Crystal Explorer 17 (Turner et al., 2017) following a literature procedure (Tan et al., 2019). The electrostatic potentials were calculated using the STO-3G basis set at the Hartree–Fock level of theory. The only red spots observed on the Hirshfeld surface mapped over dnorm, Fig. 3, arose as a result of the conventional amine-N3—H3N⋯O2(methoxy) hydrogen bond. This hydrogen bond is also reflected in the Hirshfeld surface mapped over the electrostatic potential, Fig. 4, where the positive electrostatic potential (blue) and negative electrostatic potential (red) regions are evident around the amine-H3N and methoxy-O2 atoms, respectively. Complementing the methylene-C18—H18A⋯Cg1 contact listed in Table 2, is a longer methylene-C22—H22B⋯Cg1 contact in the inter-layer region, Table 3. Each interaction is observed as an orange `hollow' on the Hirshfeld surface mapped over shape-index property, Fig. 5.
The overall two-dimensional fingerprint plot for the Hirshfeld surface of (I) is shown with characteristic pseudo-symmetric wings in the upper left and lower right sides of the de and di diagonal axes, respectively, in Fig. 6(a). The individual H⋯H, H⋯C/C⋯H, H⋯O/O⋯H, H⋯N/N⋯H and H⋯S/S⋯H contacts are illustrated in the delineated fingerprint plots in Fig. 6(b)–(f), respectively. The percentage contributions for the different interatomic contacts to the Hirshfeld surface are included in Fig. 6. The greatest contribution to the overall Hirshfeld surface is from H⋯H contacts, i.e. 66.2%. The H⋯H contacts appear as a beak-like distribution tipped at de + di ∼2.4 Å in Fig. 6(b), with the short value corresponding to the H6⋯H22A and H7⋯H17A contacts, with details listed in Table 3. The H⋯C/C⋯H contacts contribute 17.8% and appear as two sharp-symmetric wings at de + di ∼2.7 Å, Fig. 6(c). This feature reflects the C—H⋯ π contacts as discussed above. Although H⋯O/O⋯H contacts only contribute 5.2% to the overall Hirshfeld surface, they appear as the shortest contacts at de + di ∼2.1 Å, being 0.6 Å shorter than the sum of their van der Waals radii, Fig. 6(d), and reflect the conventional hydrogen bonding leading to the supramolecular chain. The H⋯N/N⋯H and H⋯S/S⋯H contacts contribute 4.6 and 4.3%, respectively, to the overall Hirshfeld surface. These contacts are reflected as pseudo-mirrored features at de + di ∼3.0 Å in each of Fig. 6(e) and (f), with the minimum distance being around the sum of their respective van der Waals radii. The other interatomic contacts, i.e. C⋯C and C⋯N/N⋯C, have a negligible effect on the molecular packing and their contributions to the overall Hirshfeld surface are 1.7 and 0.2%, respectively.
5. Computational chemistry
In the present analysis, the pairwise interaction energies between the molecules in the crystal of (I) were calculated using the wave function at the B3LYP/DGDZVP level of theory. The total interaction energies (Etot) as well as individual energy components, namely electrostatic (Eele), polarization (Epol), dispersion (Edis) and exchange-repulsion (Erep) are collated in Table 4. The most significant stabilization energies in the intra-layer region arise from the amine-N3—H3N⋯O2(methoxy) hydrogen bond (Etot = −83.4 kJ mol−1). In addition to the methylene-C18—H18A⋯Cg1 contacts, molecules in the intra-layer region are stabilized by a number of H⋯H contacts, notably H7⋯H17A contacts with a separation of 2.32 Å, Table 3. Therefore, the dispersion term, i.e. Edis, makes the major contribution to the overall interaction energy in the intra-layer region.
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The greatest stabilization energies in the inter-layer region relate to the weak methylene-C22—H22B⋯Cg1 contact (Etot = −25.7 kJ mol−1) with the remaining intermolecular contacts between molecules being stabilizing H⋯H contacts. The nature of these contacts leads to the dominance of the Edis component in the molecular packing, Table 4. This observation is also highlighted in the energy framework diagrams of Fig. 7, where the magnitudes of intermolecular energies are represented graphically in the form of cylinders; the wider the cylinder, the greater the energy. The total Eele and Edis components of all pairwise interactions sum to −127.0 and −329.5 kJ mol−1, respectively.
6. Database survey
The represents the fourth example of a diorganotin derivative containing the same Schiff base ligand, i.e. RR'Sn(L). Each of the literature structures were reported during 2020, i.e. R = R′ = Me (II) and Ph (III) (Cambridge Structural Database refcodes MUWQED and MUWQAZ, respectively; Yusof et al., 2020) and R = n-Bu and R′ = CH2SiMe3 (IV; CUJHIB; Xie et al., 2020). It is noted that the R = R′ = Ph derivative (III) co-crystallized with one-half mole equivalent of 3-methoxysalicylaldehyde azine (Yusof et al., 2020). Also, two positions were modelled for the tin atom in (IV), with the major component having a site occupancy factor = 0.523 and is designated hereafter as (IVa). Selected geometric parameters for the four structures are collated in Table 5 and an overlay diagram for (I)–(IVa) is shown in Fig. 8. None of the molecules has and all present distorted C2NOS coordination geometries. With the exception of (II), the molecules have intermediate coordination geometries with τ (Addison et al., 1984) ranging from 0.52 in (I) to 0.60 in each of (III) and (IVa). The standout molecule is the dimethyltin derivative (II) which, with τ = 0.00, is well described as having a square-pyramidal geometry. The S1—Sn—O1 angles span a range greater than 15°, i.e. 145.67 (9) in (II) to 161.81 (7)° in (III).
determination of (I)
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The hydrogen-bonding patterns formed in the crystals of (I)–(IV) are also distinct. Supramolecular helical chains, sustained by amine-H⋯O(methoxy) hydrogen bonds are found in each of (I) and (IV). However, in (II), the interactions leading to a helical chain are of the type amine-H⋯O(phenoxide). A further distinction is noted in the crystal of (III) in that dimeric aggregates are formed, featuring amine-N—H⋯S(thiolate) hydrogen bonding.
7. Synthesis and crystallization
The synthesis of the Schiff base precursor, [2-(2-hydroxy-3-methoxybenzylidene)-N-phenylhydrazine carbothioamide] was according to the procedure described in the literature (Đilović et al., 2008; Kalaivani et al., 2012) with some modifications (Yusof et al., 2020). 4-Phenylthiosemicarbazide (1.67 g, 10 mmol) was dissolved in methanol (40 ml) with stirring and heating (313 K) over a period of 30 min. 2-Hydroxy-3-methoxybenzaldehyde (1.52 g, 10 mmol) in methanol (10 ml) was added to the thiosemicarbazide solution and stirred at room temperature for 4 h. Upon cooling, a crystalline product began to form which was filtered, washed with cold methanol and dried in a desiccator over anhydrous silica gel.
Synthesis of (I): The Schiff base (0.60 g, 2 mmol) was dissolved in a mixture of ethanol:DMF (7:3; 100 ml). Then, Et3N (0.28 ml, 2 mmol) was added dropwise followed by reflux for 2 h. Then, dibutyltin(IV) dichloride (0.61 g, 2 mmol) was added to the mixture followed by reflux for 6 h. The mixture was filtered while hot to remove the [Et3NH]Cl salt that formed and the filtrate was kept at room temperature until bright-yellow crystals appeared. Yield 62%, m.p. 384–385 K. FT–IR (ATR, cm−1): 3322 ν(N—H), 1582 ν(C=N), 1076 ν(N—N), 853 ν(C=S). 1H NMR (CDCl3, 700 MHz) δ: 8.63 (s, 1H, NH), 7.54 (s, 1H, N—CH), 6.65–7.32 (m, 8H, Ar—H), 3.85 (s, 3H, O—CH3), n-Bu: 1.68 [t, 4H, Hα], 1.61 [m, 4H, Hβ], 1.34 [m, 4H, Hγ], 0.87 [t, 6H, Hδ]. 13C NMR (CDCl3, 175 MHz) δ: 162.5 (S2C), 159.0 (C=N), 151.3, 139.6, 128.9, 125.4, 123.1, 120.4, 120.0, 116.9, 116.3, 115.7 (Ar—C), 56.3 (O—CH3), n-Bu: 27.5 (Cα), 26.5 (Cβ), 26.0 (Cγ), 13.6 (Cδ).
8. Refinement
Crystal data, data collection and structure . The carbon-bound H atoms were placed in calculated positions (C—H = 0.95–0.99 Å) and were included in the in the riding-model approximation, with Uiso(H) set to 1.2–1.5Ueq(C). The N-bound H atom was located in a difference-Fourier map, but was refined with a N—H = 0.88±0.01 Å distance restraint, and with Uiso(H) set to 1.2Ueq(N). The maximum and minimum residual electron density peaks of 1.63 and 0.52 e Å−3, respectively, were located 0.97 and 0.53 Å from the Sn atom.
details are summarized in Table 6
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Supporting information
CCDC reference: 2063179
https://doi.org/10.1107/S2056989021001870/hb7969sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989021001870/hb7969Isup2.hkl
Data collection: CrysAlis PRO (Rigaku OD, 2015); cell
CrysAlis PRO (Rigaku OD, 2015); data reduction: CrysAlis PRO (Rigaku OD, 2015); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).[Sn(C4H9)2(C15H13N3O2S)] | F(000) = 1088 |
Mr = 532.26 | Dx = 1.455 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
a = 11.2720 (3) Å | Cell parameters from 9470 reflections |
b = 16.1954 (3) Å | θ = 3.8–28.9° |
c = 14.2778 (3) Å | µ = 1.16 mm−1 |
β = 111.180 (3)° | T = 150 K |
V = 2430.41 (10) Å3 | Prism, yellow |
Z = 4 | 0.15 × 0.10 × 0.06 mm |
Rigaku Oxford Diffraction Xcalibur, Eos, Gemini diffractometer | 5967 independent reflections |
Radiation source: fine-focus sealed X-ray tube, Enhance (Mo) X-ray Source | 4699 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.051 |
Detector resolution: 16.1952 pixels mm-1 | θmax = 29.3°, θmin = 3.8° |
ω scans | h = −15→14 |
Absorption correction: multi-scan (CrysAlis PRO; Rigaku OD, 2015) | k = −21→22 |
Tmin = 0.850, Tmax = 1.000 | l = −19→18 |
26999 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.033 | Hydrogen site location: mixed |
wR(F2) = 0.076 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0297P)2 + 1.1545P] where P = (Fo2 + 2Fc2)/3 |
5967 reflections | (Δ/σ)max = 0.001 |
277 parameters | Δρmax = 1.63 e Å−3 |
1 restraint | Δρmin = −0.52 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 | ||
Sn | 0.30782 (2) | 0.63922 (2) | 0.20843 (2) | 0.02658 (7) | |
S1 | 0.17922 (7) | 0.76839 (5) | 0.21316 (5) | 0.03737 (18) | |
O1 | 0.41536 (16) | 0.53123 (10) | 0.26242 (13) | 0.0299 (4) | |
O2 | 0.55992 (16) | 0.40842 (10) | 0.25269 (13) | 0.0279 (4) | |
N1 | 0.3367 (2) | 0.74015 (12) | 0.40760 (15) | 0.0271 (5) | |
N2 | 0.38235 (19) | 0.67314 (12) | 0.36939 (15) | 0.0245 (5) | |
N3 | 0.1999 (2) | 0.85096 (13) | 0.37649 (16) | 0.0278 (5) | |
H3N | 0.142 (2) | 0.8768 (15) | 0.3282 (15) | 0.033* | |
C1 | 0.2476 (2) | 0.78406 (15) | 0.34279 (18) | 0.0267 (6) | |
C2 | 0.4807 (2) | 0.63876 (15) | 0.43827 (19) | 0.0266 (5) | |
H2 | 0.507201 | 0.663195 | 0.503089 | 0.032* | |
C3 | 0.5533 (2) | 0.56903 (15) | 0.42817 (18) | 0.0253 (5) | |
C4 | 0.5195 (2) | 0.51976 (14) | 0.34156 (18) | 0.0231 (5) | |
C5 | 0.5993 (2) | 0.45193 (15) | 0.34154 (18) | 0.0240 (5) | |
C6 | 0.7057 (2) | 0.43422 (16) | 0.4235 (2) | 0.0315 (6) | |
H6 | 0.758465 | 0.388936 | 0.421749 | 0.038* | |
C7 | 0.7367 (3) | 0.48344 (17) | 0.5104 (2) | 0.0373 (7) | |
H7 | 0.809490 | 0.470558 | 0.567769 | 0.045* | |
C8 | 0.6629 (2) | 0.54928 (16) | 0.51260 (19) | 0.0320 (6) | |
H8 | 0.685130 | 0.582370 | 0.571384 | 0.038* | |
C9 | 0.6339 (3) | 0.33893 (18) | 0.2478 (2) | 0.0414 (7) | |
H9A | 0.720214 | 0.356915 | 0.256299 | 0.062* | |
H9B | 0.595020 | 0.311870 | 0.182395 | 0.062* | |
H9C | 0.637687 | 0.299962 | 0.301309 | 0.062* | |
C10 | 0.2229 (2) | 0.87931 (15) | 0.47493 (19) | 0.0246 (5) | |
C11 | 0.3071 (3) | 0.84289 (16) | 0.5628 (2) | 0.0321 (6) | |
H11 | 0.356486 | 0.796350 | 0.559100 | 0.039* | |
C12 | 0.3174 (3) | 0.87544 (17) | 0.6549 (2) | 0.0355 (7) | |
H12 | 0.374328 | 0.850489 | 0.714380 | 0.043* | |
C13 | 0.2475 (3) | 0.94306 (17) | 0.6629 (2) | 0.0353 (6) | |
H13 | 0.254424 | 0.963702 | 0.726972 | 0.042* | |
C14 | 0.1671 (3) | 0.98029 (17) | 0.5762 (2) | 0.0331 (6) | |
H14 | 0.119945 | 1.027809 | 0.580593 | 0.040* | |
C15 | 0.1547 (2) | 0.94894 (16) | 0.4831 (2) | 0.0286 (6) | |
H15 | 0.099062 | 0.975153 | 0.424064 | 0.034* | |
C16 | 0.1475 (2) | 0.56202 (17) | 0.13464 (19) | 0.0320 (6) | |
H16A | 0.073373 | 0.597705 | 0.099569 | 0.038* | |
H16B | 0.165615 | 0.529157 | 0.082891 | 0.038* | |
C17 | 0.1111 (3) | 0.50319 (18) | 0.2027 (2) | 0.0368 (7) | |
H17A | 0.078865 | 0.535372 | 0.247468 | 0.044* | |
H17B | 0.187726 | 0.472697 | 0.245367 | 0.044* | |
C18 | 0.0095 (3) | 0.44156 (18) | 0.1427 (2) | 0.0408 (7) | |
H18A | −0.067397 | 0.472273 | 0.101010 | 0.049* | |
H18B | 0.041312 | 0.410471 | 0.096902 | 0.049* | |
C19 | −0.0267 (3) | 0.3812 (2) | 0.2085 (3) | 0.0630 (11) | |
H19A | 0.046823 | 0.346452 | 0.244721 | 0.095* | |
H19B | −0.096854 | 0.346334 | 0.166641 | 0.095* | |
H19C | −0.053386 | 0.411610 | 0.256866 | 0.095* | |
C20 | 0.4355 (3) | 0.68370 (17) | 0.1396 (2) | 0.0348 (6) | |
H20A | 0.510109 | 0.708354 | 0.192719 | 0.042* | |
H20B | 0.466511 | 0.635693 | 0.112094 | 0.042* | |
C21 | 0.3833 (3) | 0.74679 (18) | 0.0563 (2) | 0.0385 (7) | |
H21A | 0.345417 | 0.793150 | 0.081061 | 0.046* | |
H21B | 0.314902 | 0.720923 | −0.000729 | 0.046* | |
C22 | 0.4850 (3) | 0.7805 (2) | 0.0194 (2) | 0.0487 (8) | |
H22A | 0.555087 | 0.804035 | 0.077308 | 0.058* | |
H22B | 0.520427 | 0.734251 | −0.007521 | 0.058* | |
C23 | 0.4367 (5) | 0.8464 (2) | −0.0612 (3) | 0.0684 (11) | |
H23A | 0.360725 | 0.826100 | −0.115308 | 0.103* | |
H23B | 0.502935 | 0.859307 | −0.088338 | 0.103* | |
H23C | 0.415227 | 0.896385 | −0.031958 | 0.103* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Sn | 0.02994 (10) | 0.02799 (11) | 0.01860 (10) | 0.00565 (7) | 0.00492 (7) | −0.00006 (7) |
S1 | 0.0463 (4) | 0.0399 (4) | 0.0204 (3) | 0.0194 (3) | 0.0054 (3) | 0.0010 (3) |
O1 | 0.0297 (9) | 0.0269 (9) | 0.0246 (9) | 0.0067 (7) | −0.0003 (7) | −0.0032 (7) |
O2 | 0.0323 (9) | 0.0233 (9) | 0.0253 (9) | 0.0031 (7) | 0.0069 (8) | −0.0037 (7) |
N1 | 0.0342 (12) | 0.0242 (11) | 0.0205 (11) | 0.0081 (9) | 0.0068 (9) | −0.0008 (9) |
N2 | 0.0308 (11) | 0.0213 (10) | 0.0201 (11) | 0.0058 (9) | 0.0076 (9) | −0.0001 (8) |
N3 | 0.0339 (12) | 0.0270 (12) | 0.0213 (11) | 0.0122 (9) | 0.0086 (9) | 0.0040 (9) |
C1 | 0.0315 (13) | 0.0262 (13) | 0.0229 (13) | 0.0041 (11) | 0.0104 (11) | 0.0024 (10) |
C2 | 0.0313 (13) | 0.0267 (13) | 0.0191 (12) | 0.0018 (11) | 0.0059 (10) | −0.0007 (10) |
C3 | 0.0277 (12) | 0.0239 (13) | 0.0221 (13) | 0.0028 (10) | 0.0065 (10) | 0.0027 (10) |
C4 | 0.0235 (12) | 0.0219 (12) | 0.0223 (13) | 0.0006 (10) | 0.0062 (10) | 0.0014 (10) |
C5 | 0.0275 (12) | 0.0211 (12) | 0.0225 (13) | −0.0022 (10) | 0.0079 (10) | −0.0009 (10) |
C6 | 0.0323 (14) | 0.0263 (14) | 0.0337 (15) | 0.0081 (11) | 0.0093 (12) | 0.0002 (11) |
C7 | 0.0353 (15) | 0.0399 (16) | 0.0259 (15) | 0.0094 (12) | −0.0019 (12) | −0.0005 (12) |
C8 | 0.0353 (14) | 0.0299 (14) | 0.0224 (13) | 0.0051 (11) | 0.0004 (11) | −0.0045 (11) |
C9 | 0.0522 (18) | 0.0321 (15) | 0.0359 (17) | 0.0140 (13) | 0.0109 (14) | −0.0065 (13) |
C10 | 0.0283 (12) | 0.0249 (13) | 0.0225 (13) | 0.0001 (10) | 0.0114 (10) | 0.0011 (10) |
C11 | 0.0428 (16) | 0.0264 (14) | 0.0266 (14) | 0.0062 (11) | 0.0119 (12) | 0.0015 (11) |
C12 | 0.0498 (17) | 0.0332 (15) | 0.0219 (14) | 0.0005 (13) | 0.0108 (12) | 0.0007 (11) |
C13 | 0.0468 (17) | 0.0341 (15) | 0.0292 (15) | −0.0028 (13) | 0.0187 (13) | −0.0071 (12) |
C14 | 0.0334 (14) | 0.0320 (14) | 0.0391 (16) | 0.0016 (12) | 0.0193 (13) | −0.0049 (12) |
C15 | 0.0268 (13) | 0.0303 (14) | 0.0295 (14) | 0.0034 (11) | 0.0111 (11) | 0.0024 (11) |
C16 | 0.0296 (13) | 0.0392 (15) | 0.0215 (13) | 0.0030 (12) | 0.0024 (11) | 0.0001 (12) |
C17 | 0.0366 (15) | 0.0454 (17) | 0.0230 (14) | 0.0027 (13) | 0.0041 (11) | 0.0043 (12) |
C18 | 0.0341 (15) | 0.0447 (17) | 0.0377 (17) | 0.0015 (13) | 0.0059 (13) | 0.0018 (14) |
C19 | 0.048 (2) | 0.059 (2) | 0.071 (3) | −0.0058 (17) | 0.0099 (19) | 0.0203 (19) |
C20 | 0.0392 (15) | 0.0353 (15) | 0.0329 (16) | 0.0039 (12) | 0.0168 (13) | −0.0008 (12) |
C21 | 0.0435 (16) | 0.0439 (17) | 0.0300 (15) | 0.0005 (13) | 0.0155 (13) | −0.0009 (13) |
C22 | 0.059 (2) | 0.056 (2) | 0.0358 (17) | −0.0094 (17) | 0.0237 (16) | −0.0045 (15) |
C23 | 0.106 (3) | 0.060 (2) | 0.055 (2) | −0.008 (2) | 0.048 (2) | 0.0049 (19) |
Sn—S1 | 2.5598 (7) | C11—H11 | 0.9500 |
Sn—O1 | 2.1089 (16) | C12—C13 | 1.378 (4) |
Sn—N2 | 2.212 (2) | C12—H12 | 0.9500 |
Sn—C16 | 2.136 (3) | C13—C14 | 1.381 (4) |
Sn—C20 | 2.140 (3) | C13—H13 | 0.9500 |
S1—C1 | 1.747 (3) | C14—C15 | 1.382 (4) |
O1—C4 | 1.316 (3) | C14—H14 | 0.9500 |
O2—C5 | 1.377 (3) | C15—H15 | 0.9500 |
O2—C9 | 1.417 (3) | C16—C17 | 1.519 (4) |
N1—C1 | 1.304 (3) | C16—H16A | 0.9900 |
N1—N2 | 1.394 (3) | C16—H16B | 0.9900 |
N2—C2 | 1.311 (3) | C17—C18 | 1.528 (4) |
N3—C1 | 1.371 (3) | C17—H17A | 0.9900 |
N3—C10 | 1.411 (3) | C17—H17B | 0.9900 |
N3—H3N | 0.866 (10) | C18—C19 | 1.510 (4) |
C2—C3 | 1.432 (3) | C18—H18A | 0.9900 |
C2—H2 | 0.9500 | C18—H18B | 0.9900 |
C3—C4 | 1.404 (3) | C19—H19A | 0.9800 |
C3—C8 | 1.416 (3) | C19—H19B | 0.9800 |
C4—C5 | 1.420 (3) | C19—H19C | 0.9800 |
C5—C6 | 1.370 (3) | C20—C21 | 1.516 (4) |
C6—C7 | 1.408 (4) | C20—H20A | 0.9900 |
C6—H6 | 0.9500 | C20—H20B | 0.9900 |
C7—C8 | 1.359 (4) | C21—C22 | 1.525 (4) |
C7—H7 | 0.9500 | C21—H21A | 0.9900 |
C8—H8 | 0.9500 | C21—H21B | 0.9900 |
C9—H9A | 0.9800 | C22—C23 | 1.519 (5) |
C9—H9B | 0.9800 | C22—H22A | 0.9900 |
C9—H9C | 0.9800 | C22—H22B | 0.9900 |
C10—C15 | 1.393 (3) | C23—H23A | 0.9800 |
C10—C11 | 1.400 (4) | C23—H23B | 0.9800 |
C11—C12 | 1.382 (4) | C23—H23C | 0.9800 |
S1—Sn—O1 | 157.56 (5) | C11—C12—H12 | 119.1 |
S1—Sn—N2 | 77.04 (5) | C12—C13—C14 | 118.8 (3) |
S1—Sn—C16 | 96.03 (8) | C12—C13—H13 | 120.6 |
S1—Sn—C20 | 102.61 (8) | C14—C13—H13 | 120.6 |
O1—Sn—N2 | 82.75 (7) | C13—C14—C15 | 120.5 (3) |
O1—Sn—C16 | 88.11 (8) | C13—C14—H14 | 119.8 |
O1—Sn—C20 | 93.08 (9) | C15—C14—H14 | 119.8 |
N2—Sn—C16 | 126.42 (9) | C14—C15—C10 | 120.7 (2) |
N2—Sn—C20 | 109.11 (10) | C14—C15—H15 | 119.6 |
C16—Sn—C20 | 124.08 (11) | C10—C15—H15 | 119.6 |
C1—S1—Sn | 96.29 (8) | C17—C16—Sn | 115.28 (17) |
C4—O1—Sn | 130.37 (15) | C17—C16—H16A | 108.5 |
C5—O2—C9 | 116.9 (2) | Sn—C16—H16A | 108.5 |
C1—N1—N2 | 116.5 (2) | C17—C16—H16B | 108.5 |
C2—N2—N1 | 111.6 (2) | Sn—C16—H16B | 108.5 |
C2—N2—Sn | 125.07 (17) | H16A—C16—H16B | 107.5 |
N1—N2—Sn | 123.00 (14) | C16—C17—C18 | 111.8 (2) |
C1—N3—C10 | 130.7 (2) | C16—C17—H17A | 109.2 |
C1—N3—H3N | 112.2 (19) | C18—C17—H17A | 109.2 |
C10—N3—H3N | 116.8 (19) | C16—C17—H17B | 109.2 |
N1—C1—N3 | 118.8 (2) | C18—C17—H17B | 109.2 |
N1—C1—S1 | 127.2 (2) | H17A—C17—H17B | 107.9 |
N3—C1—S1 | 114.06 (17) | C19—C18—C17 | 113.0 (3) |
N2—C2—C3 | 128.2 (2) | C19—C18—H18A | 109.0 |
N2—C2—H2 | 115.9 | C17—C18—H18A | 109.0 |
C3—C2—H2 | 115.9 | C19—C18—H18B | 109.0 |
C4—C3—C8 | 119.8 (2) | C17—C18—H18B | 109.0 |
C4—C3—C2 | 123.6 (2) | H18A—C18—H18B | 107.8 |
C8—C3—C2 | 116.5 (2) | C18—C19—H19A | 109.5 |
O1—C4—C3 | 123.4 (2) | C18—C19—H19B | 109.5 |
O1—C4—C5 | 118.6 (2) | H19A—C19—H19B | 109.5 |
C3—C4—C5 | 118.0 (2) | C18—C19—H19C | 109.5 |
C6—C5—O2 | 124.8 (2) | H19A—C19—H19C | 109.5 |
C6—C5—C4 | 121.4 (2) | H19B—C19—H19C | 109.5 |
O2—C5—C4 | 113.7 (2) | C21—C20—Sn | 116.88 (19) |
C5—C6—C7 | 119.7 (2) | C21—C20—H20A | 108.1 |
C5—C6—H6 | 120.1 | Sn—C20—H20A | 108.1 |
C7—C6—H6 | 120.1 | C21—C20—H20B | 108.1 |
C8—C7—C6 | 120.4 (2) | Sn—C20—H20B | 108.1 |
C8—C7—H7 | 119.8 | H20A—C20—H20B | 107.3 |
C6—C7—H7 | 119.8 | C20—C21—C22 | 112.7 (3) |
C7—C8—C3 | 120.7 (2) | C20—C21—H21A | 109.1 |
C7—C8—H8 | 119.7 | C22—C21—H21A | 109.1 |
C3—C8—H8 | 119.7 | C20—C21—H21B | 109.1 |
O2—C9—H9A | 109.5 | C22—C21—H21B | 109.1 |
O2—C9—H9B | 109.5 | H21A—C21—H21B | 107.8 |
H9A—C9—H9B | 109.5 | C23—C22—C21 | 113.9 (3) |
O2—C9—H9C | 109.5 | C23—C22—H22A | 108.8 |
H9A—C9—H9C | 109.5 | C21—C22—H22A | 108.8 |
H9B—C9—H9C | 109.5 | C23—C22—H22B | 108.8 |
C15—C10—C11 | 118.8 (2) | C21—C22—H22B | 108.8 |
C15—C10—N3 | 116.0 (2) | H22A—C22—H22B | 107.7 |
C11—C10—N3 | 125.2 (2) | C22—C23—H23A | 109.5 |
C12—C11—C10 | 119.2 (3) | C22—C23—H23B | 109.5 |
C12—C11—H11 | 120.4 | H23A—C23—H23B | 109.5 |
C10—C11—H11 | 120.4 | C22—C23—H23C | 109.5 |
C13—C12—C11 | 121.9 (3) | H23A—C23—H23C | 109.5 |
C13—C12—H12 | 119.1 | H23B—C23—H23C | 109.5 |
C1—N1—N2—C2 | 173.0 (2) | O1—C4—C5—O2 | 4.0 (3) |
C1—N1—N2—Sn | −1.2 (3) | C3—C4—C5—O2 | −178.7 (2) |
N2—N1—C1—N3 | −179.6 (2) | O2—C5—C6—C7 | 179.8 (2) |
N2—N1—C1—S1 | −0.2 (4) | C4—C5—C6—C7 | 0.7 (4) |
C10—N3—C1—N1 | −6.2 (4) | C5—C6—C7—C8 | −1.3 (4) |
C10—N3—C1—S1 | 174.3 (2) | C6—C7—C8—C3 | 0.6 (5) |
Sn—S1—C1—N1 | 1.1 (3) | C4—C3—C8—C7 | 0.7 (4) |
Sn—S1—C1—N3 | −179.43 (18) | C2—C3—C8—C7 | 179.1 (3) |
N1—N2—C2—C3 | 180.0 (2) | C1—N3—C10—C15 | −177.9 (3) |
Sn—N2—C2—C3 | −6.0 (4) | C1—N3—C10—C11 | 1.8 (4) |
N2—C2—C3—C4 | −7.4 (4) | C15—C10—C11—C12 | 1.8 (4) |
N2—C2—C3—C8 | 174.2 (3) | N3—C10—C11—C12 | −177.9 (3) |
Sn—O1—C4—C3 | 26.6 (4) | C10—C11—C12—C13 | −0.2 (4) |
Sn—O1—C4—C5 | −156.24 (18) | C11—C12—C13—C14 | −1.5 (4) |
C8—C3—C4—O1 | 175.9 (2) | C12—C13—C14—C15 | 1.6 (4) |
C2—C3—C4—O1 | −2.4 (4) | C13—C14—C15—C10 | 0.0 (4) |
C8—C3—C4—C5 | −1.2 (4) | C11—C10—C15—C14 | −1.7 (4) |
C2—C3—C4—C5 | −179.5 (2) | N3—C10—C15—C14 | 178.0 (2) |
C9—O2—C5—C6 | 1.9 (4) | Sn—C16—C17—C18 | −171.27 (19) |
C9—O2—C5—C4 | −179.0 (2) | C16—C17—C18—C19 | 178.9 (3) |
O1—C4—C5—C6 | −176.8 (2) | Sn—C20—C21—C22 | 174.5 (2) |
C3—C4—C5—C6 | 0.5 (4) | C20—C21—C22—C23 | −177.7 (3) |
Cg1 is the centroid of the (C10–C15) ring. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3N···O2i | 0.87 (2) | 2.21 (2) | 2.990 (3) | 150 (2) |
C18—H18A···Cg1ii | 0.99 | 2.81 | 3.730 (3) | 154 |
Symmetry codes: (i) −x+1/2, y+1/2, −z+1/2; (ii) x−1/2, −y+3/2, z−1/2. |
Contact | Distance | Symmetry operation |
N3—H3N···O2 | 2.09 | -x + 1/2, y + 1/2, -z + 1/2 |
C18—H18A···Cg1 | 2.81 | x - 1/2, -y - 3/2, z - 1/2 |
C22—H22B···Cg1 | 3.28 | x + 1/2, -y + 3/2, z - 1/2 |
H6···H22A | 2.32 | -x + 3/2, y - 1/2, -z + 1/2 |
H7···H17A | 2.32 | -x + 1, -y + 1, -z + 1 |
Note: (a) The interatomic distances are calculated in Crystal Explorer 17 (Turner et al., 2017) with the X—H bond lengths adjusted to their neutron values. |
Contact | R (Å) | Eele | Epol | Edis | Erep | Etot |
Intra-layer region | ||||||
N3—H3N···O2i | 8.36 | -51.6 | -10.0 | -77.3 | 74.2 | -83.4 |
H7···H17Aiv + | ||||||
H9C···H11iv + | ||||||
H9C···H12iv | 7.54 | -30.2 | -3.3 | -88.0 | 78.5 | -62.5 |
C18—H18A···Cg1ii+ | ||||||
H8···H21Av | 7.93 | -19.5 | -2.6 | -49.7 | 43.0 | -39.2 |
H16A···H18Bvi + | ||||||
H16B···H18Avi | 10.52 | -4.3 | -0.1 | -24.5 | 18.6 | -14.5 |
Inter-layer region | ||||||
C22—H22B···Cg1iii | 11.00 | -6.8 | -1.3 | -32.0 | 16.7 | -25.7 |
H9A···H22Bvii+ | ||||||
H9A···H23Avii | 11.46 | -2.9 | -0.7 | -18.7 | 12.0 | -12.6 |
H14···H15viii | 15.83 | -6.7 | -0.7 | -14.1 | 18.3 | -8.6 |
H6···H22Aix+ | ||||||
H7···H23Bix | 12.63 | -1.5 | -0.4 | -11.6 | 6.0 | -8.3 |
H9A···H19Cx | 11.27 | -1.3 | -0.2 | -6.4 | 3.1 | -5.2 |
H12···H23Axi | 14.28 | -2.2 | -0.1 | -7.2 | 6.1 | -4.9 |
Symmetry operations: (i) -x + 1/2, y + 1/2, -z + 1/2; (ii) x - 1/2, -y + 3/2, z - 1/2; (iii) x + 1/2, -y + 3/2, z - 1/2; (iv) -x + 1, -y + 1, -z + 1; (v) x + 1/2, -y + 3/2, z + 1/2; (vi) -x, -y + 1, -z; (vii) -x + 1, -y + 1, -z; (viii) -x, -y + 2, -z + 1; (ix) -x + 3/2, y - 1/2, -z + 1/2; (x) x + 1, y, z; (xi) x, y, z + 1. |
Compound | R, R' | Sn—S | Sn—O1 | Sn—N2 | S1—Sn—O1 | C—Sn—C | τ | Ref. |
(I) | nBu, nBu | 2.5598 (7) | 2.1089 (16) | 2.212 (2) | 157.56 (5) | 124.08 (11) | 0.52 | This work |
(II) | Me, Me | 2.4982 (12) | 2.085 (3) | 2.257 (3) | 145.67 (9) | 114.82 (18) | 0.00 | Yusof et al. (2020) |
(III) | Ph, Ph | 2.5475 (8) | 2.0853 (19) | 2.176 (3) | 161.81 (7) | 121.46 (12) | 0.60 | Yusof et al. (2020) |
(IV)a | nBu, CH2SiM3 | 2.485 (5) | 2.152 (6) | 2.184 (6) | 159.4 (2) | 121.6 (4) | 0.60 | Xie et al. (2020) |
(IV)b | 2.587 (4) | 2.063 (6) | 2.218 (7) | 157.6 (3) | 123.8 (4) | 0.56 |
Notes: (a) major component of the disorder with a site occupancy = 0.527 and (b) minor component with occupancy 0.473. |
Footnotes
‡Additional correspondence author, email: thahira301@yahoo.com.
Acknowledgements
The authors thank the School of Distance Education, Universiti Sains Malaysia and the Department of Chemistry, Universiti Putra Malaysia for providing research facilities and technical support.
Funding information
This research was funded by Universiti Putra Malaysia under the Putra Group Initiative (IPB No. 9581001). Crystallographic research at Sunway University is supported by Sunway University Sdn Bhd (Grant No. GRTIN-IRG-01–2021).
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