cis-{1-Butyl-3-[2-(phenyl­sulfan­yl)eth­yl]-4-imidazolin-2-yl-κ2C2,S′}di­chlorido­platinum(II)

Liang, B.-B.; Xiong, H.-G.; Hong, W.-Y.; Yao, H.-G.

doi:10.1107/S2414314620014339

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 5| Part 11| November 2020| x201433

https://doi.org/10.1107/S2414314620014339

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cis-{1-Butyl-3-[2-(phenylsulfanyl)ethyl]-4-imidazolin-2-yl-κ²C²,S′}dichloridoplatinum(II)

Bing-Bing Liang,^a Hong-Gang Xiong,^a Wan-Yu Hong ^a and Hua-Gang Yao ^a ^*

^aSchool of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Guangdong 528458, People's Republic of China
^*Correspondence e-mail: yaohg518@126.com

Edited by H. Ishida, Okayama University, Japan (Received 22 May 2020; accepted 28 October 2020; online 3 November 2020)

The asymmetric unit of the title compound, [PtCl₂(C₁₅H₂₀N₂S)], comprises one Pt^II ion, one N-heterocyclic carbene(NHC)-thioether ligand and two chloride ions. The Pt^II ion is four-coordinated by one C atom and one S atom of the NHC-thioether ligand, and by two chloride ions, forming an approximately square-planar geometry. In the crystal, the molecules are linked via C—H⋯Cl and C—H⋯π interactions, forming a layer parallel to the ab plane.

Keywords: crystal structure; Pt complex; N-heterocyclic carbene(NHC)-thioether ligand.

CCDC reference: 2041081

Structure description

Nitrogen heterocyclic carbene (NHC) exhibits attractive advantages such as simple operation and mild conditions in organic catalytic synthesis (Enders et al., 2007 ). In addition, as a neutral two-electron donor, NHC is currently regarded as the most effective ligand for the synthesis of new organometallic complexes owing to its unique features (Hahn & Jahnke, 2008 ; Nelson & Nolan, 2013 ). The first distinctive characteristic is the strong donor property of NHC ligands, which makes the interaction with metal center closer (Perrin et al., 2001 ; Chianese et al., 2003 ). The second one is that NHC can be flexibly modified by introducing functional groups onto the nitrogen atoms of the N-heterocycle ring. Over the past two decades, numerous attempts have been made to construct diverse donor-functionalized NHCs and their organometallic complexes, and N-, O- and P-functionalized NHCs have been developed and applied in organic synthesis, drug discovery and materials science (Kühl, 2007 ). However, there are still rare investigations of NHC with S-donor complexes (Liu et al., 2017 ). As soft and electron-rich ligands, thioethers usually have versatile coordination chemistry, and can form strong M—S bonds with the metal center (Bierenstiel & Cross, 2011 ; Yuan & Huynh, 2012 ). The development of new organometallic complexes bearing NHC-thioether ligands (Rosen et al., 2013 ) is thus highly desirable. In recent years, NHC complexes with group 10 metals have received increasing attention because of their catalytic activities. In contrast to complexes of lighter homologues, Pt^II-NHC complexes have been less well studied. The novel title metal Pt^II complex combined with an NHC-thioether ligand was designed and synthesized.

The asymmetric unit of the title complex is composed of one Pt^II ion, one NHC-thioether ligand, and two chloride ions. As shown in Fig. 1, the Pt^II ion is four-coordinated by one C atom and one S atom of the NHC-thioether ligand, and by two chloride ions in a nearly square-planar environment. The thioether side chain coordinates to the Pt^II atom in a chelating fashion, forming a six-membered ring with a distorted boat conformation. The Pt—C and Pt—S bond lengths are 1.968 (12) and 2.266 (3) Å, respectively, while the C—Pt—S bond angle is 87.93 (11)°. The two Pt—Cl bond lengths are different from each other [Pt1—Cl1 = 2.360 (3) Å and Pt1—Cl2 = 2.329 (3) Å]. In the crystal, molecules are linked via C—H⋯Cl and C—H⋯π interactions (Table 1), forming a layer parallel to the ab plane (Figs. 2 and 3). A weak intramolecular C—H⋯π interaction is also observed.

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the N1/C10/C9/N2/C11 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9⋯Cl2ⁱ	0.93	2.58	3.485 (12)	163
C2—H2⋯Cg1	0.93	2.98	3.828 (13)	151
C14—H14A⋯Cg1ⁱⁱ	0.97	2.82	3.480 (13)	126
Symmetry codes: (i) ; (ii) $[-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 1
The structure of the title complex, with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

Figure 2
A packing diagram of the title compound, showing intra- and intermolecular C—H⋯π interactions (dashed lines).

Figure 3
A view of the crystal packing of the title complex. Dashed lines denote the intermolecular C—H⋯Cl hydrogen bonds.

Synthesis and crystallization

N-Heterocyclic carbene (NHC)-thioether ligand was synthesized by a slight modification of a reported procedure (Liu et al., 2017). Butyl-imidazole and 2-chloroethylbenzene sulfide (molar ratio 1: 1) were dissolved in acetonitrile at 393 K for 2 days to obtain a dark-brown liquid, and then the solvent was removed by evaporation. The residue was washed repeatedly with diethyl ether, and a brownish-yellow solid was obtained.

The title complex was synthesized from the reaction of the NHC-thioether ligand with potassium tetrachloroplatinate. A reaction tube was charged with the NHC-thioether ligand (0.1710 g, 0.576 mM) and 6 ml of acetonitrile. The tube was evacuated and back-filled with nitrogen. Then a solution of potassium tetrachloroplatinate (0.200 g, 0.480 mM) in 2 ml of water was added in the dark. Keeping it in the dark, the reaction mixture was allowed to stir at 353 K for 24 h. The mixture was concentrated in vacuo and purified by silica gel column chromatography. Pale-yellow rectangular crystals were obtained from the solution at room temperature.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. The anisotropy of displacement ellipsoid of atom C9 was restrained with ISOR.

Table 2
Experimental details

Crystal data
Chemical formula	[PtCl₂(C₁₅H₂₀N₂S)]
M_r	526.38
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	100
a, b, c (Å)	8.4254 (3), 10.1535 (4), 20.2262 (10)
V (Å³)	1730.30 (13)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	8.53
Crystal size (mm)	0.12 × 0.11 × 0.09

Data collection
Diffractometer	Rigaku Oxford Diffraction SuperNova, Dual, Cu at zero, AtlasS2
Absorption correction	Multi-scan (CrysAlis PRO; Rigaku OD, 2015 $[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]$ )
T_min, T_max	0.310, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	11246, 3045, 2911
R_int	0.050
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.033, 0.073, 1.10
No. of reflections	3045
No. of parameters	190
No. of restraints	6
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.27, −0.90
Absolute structure	Flack x determined using 1166 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	−0.020 (7)
Computer programs: CrysAlis PRO (Rigaku OD, 2015 $[Rigaku OD (2015). CrysAlis PRO. Rigaku Oxford Diffraction, Yarnton, England.]$ ), SHELXT (Sheldrick, 2015a ), SHELXL2018/3 (Sheldrick, 2015b ) and OLEX2 (Dolomanov et al., 2009 ).

Structural data

CCDC reference: 2041081

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S2414314620014339/is5540sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314620014339/is5540Isup2.hkl

checkCIF report

Computing details top

Data collection: CrysAlis PRO (Rigaku OD, 2015); cell refinement: 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: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

cis-{1-Butyl-3-[2-(phenylsulfanyl)ethyl]-4-imidazolin-2-yl-κ²C²,S'}dichloridoplatinum(II) top

Crystal data top

[PtCl₂(C₁₅H₂₀N₂S)]	D_x = 2.021 Mg m⁻³
M_r = 526.38	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P2₁2₁2₁	Cell parameters from 6072 reflections
a = 8.4254 (3) Å	θ = 2.3–29.3°
b = 10.1535 (4) Å	µ = 8.53 mm⁻¹
c = 20.2262 (10) Å	T = 100 K
V = 1730.30 (13) Å³	Block, colourless
Z = 4	0.12 × 0.11 × 0.09 mm
F(000) = 1008

Data collection top

Rigaku Oxford Diffraction SuperNova, Dual, Cu at zero, AtlasS2 diffractometer	3045 independent reflections
Radiation source: micro-focus sealed X-ray tube, SuperNova (Mo) X-ray Source	2911 reflections with I > 2σ(I)
Mirror monochromator	R_int = 0.050
Detector resolution: 5.2684 pixels mm^-1	θ_max = 25.0°, θ_min = 2.0°
ω scans	h = −9→10
Absorption correction: multi-scan (CrysAlisPro; Rigaku OD, 2015)	k = −10→12
T_min = 0.310, T_max = 1.000	l = −24→22
11246 measured reflections

Refinement top

Refinement on F²	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.033	w = 1/[σ²(F_o²) + (0.0237P)² + 8.5737P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.073	(Δ/σ)_max < 0.001
S = 1.10	Δρ_max = 1.27 e Å⁻³
3045 reflections	Δρ_min = −0.90 e Å⁻³
190 parameters	Absolute structure: Flack x determined using 1166 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
6 restraints	Absolute structure parameter: −0.020 (7)
Primary atom site location: dual

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Pt1	0.63221 (5)	0.45155 (4)	0.36816 (2)	0.01172 (13)
Cl1	0.8671 (4)	0.3701 (3)	0.41687 (15)	0.0251 (7)
Cl2	0.7685 (3)	0.4970 (3)	0.27062 (15)	0.0166 (7)
S1	0.5012 (4)	0.3876 (3)	0.46058 (16)	0.0132 (6)
N1	0.3999 (10)	0.6337 (9)	0.2997 (5)	0.013 (2)
N2	0.2959 (10)	0.4495 (10)	0.3301 (5)	0.013 (2)
C1	0.4671 (13)	0.5293 (12)	0.5109 (6)	0.017 (3)
C2	0.3753 (16)	0.6352 (11)	0.4903 (6)	0.022 (3)
H2	0.324679	0.633418	0.449406	0.027*
C3	0.3602 (18)	0.7440 (11)	0.5317 (6)	0.023 (3)
H3	0.301393	0.816485	0.517916	0.027*
C4	0.4319 (15)	0.7454 (13)	0.5932 (7)	0.026 (3)
H4	0.421705	0.818696	0.620501	0.031*
C5	0.5187 (15)	0.6376 (14)	0.6141 (7)	0.028 (3)
H5	0.565556	0.637828	0.655695	0.034*
C6	0.5362 (14)	0.5289 (13)	0.5730 (6)	0.023 (3)
H6	0.594069	0.456209	0.587208	0.028*
C7	0.2978 (14)	0.3408 (13)	0.4385 (6)	0.017 (3)
H7A	0.270431	0.259251	0.460755	0.021*
H7B	0.225027	0.408416	0.453583	0.021*
C8	0.2785 (13)	0.3224 (11)	0.3637 (7)	0.016 (3)
H8A	0.358118	0.261421	0.347493	0.019*
H8B	0.174644	0.285757	0.354193	0.019*
C9	0.1750 (14)	0.5213 (13)	0.3000 (6)	0.020 (3)
H9	0.069889	0.495503	0.294379	0.024*
C10	0.2414 (14)	0.6358 (12)	0.2805 (6)	0.015 (3)
H10	0.190345	0.703945	0.258351	0.018*
C11	0.4343 (14)	0.5184 (11)	0.3288 (6)	0.016 (3)
C12	0.5054 (15)	0.7492 (12)	0.2959 (6)	0.018 (3)
H12A	0.477671	0.801717	0.257510	0.021*
H12B	0.614370	0.719995	0.290687	0.021*
C13	0.4914 (14)	0.8325 (11)	0.3576 (6)	0.018 (3)
H13A	0.533278	0.783493	0.394901	0.022*
H13B	0.380163	0.850067	0.366229	0.022*
C14	0.5803 (14)	0.9636 (13)	0.3520 (6)	0.023 (3)
H14A	0.691832	0.946477	0.343681	0.028*
H14B	0.538795	1.012962	0.314704	0.028*
C15	0.5640 (17)	1.0449 (15)	0.4139 (7)	0.037 (4)
H15A	0.620925	1.126163	0.408726	0.055*
H15B	0.453847	1.063416	0.421815	0.055*
H15C	0.606756	0.996986	0.450767	0.055*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pt1	0.0068 (2)	0.0125 (2)	0.0158 (2)	−0.00009 (17)	0.0003 (2)	−0.0010 (2)
Cl1	0.0119 (14)	0.0317 (17)	0.0317 (18)	0.0032 (16)	−0.0018 (16)	0.0097 (14)
Cl2	0.0094 (15)	0.0230 (15)	0.0174 (16)	−0.0007 (11)	0.0022 (12)	−0.0003 (12)
S1	0.0116 (15)	0.0097 (15)	0.0183 (17)	−0.0005 (11)	0.0018 (13)	0.0005 (13)
N1	0.004 (5)	0.014 (5)	0.022 (6)	0.001 (4)	−0.004 (4)	0.000 (4)
N2	0.010 (3)	0.012 (3)	0.016 (3)	0.000 (2)	−0.001 (2)	0.001 (2)
C1	0.011 (6)	0.020 (7)	0.020 (7)	0.000 (5)	0.004 (5)	−0.006 (6)
C2	0.013 (6)	0.024 (7)	0.030 (7)	−0.002 (6)	0.002 (7)	−0.003 (6)
C3	0.029 (7)	0.010 (6)	0.029 (8)	0.005 (6)	0.002 (7)	−0.003 (5)
C4	0.021 (7)	0.023 (7)	0.033 (9)	−0.006 (5)	0.011 (6)	−0.018 (7)
C5	0.017 (7)	0.042 (9)	0.026 (9)	0.001 (6)	−0.005 (6)	−0.012 (7)
C6	0.013 (7)	0.025 (8)	0.032 (8)	0.007 (5)	−0.004 (5)	0.000 (6)
C7	0.015 (6)	0.022 (7)	0.016 (7)	−0.007 (5)	−0.002 (5)	0.001 (6)
C8	0.008 (6)	0.016 (6)	0.023 (7)	−0.003 (4)	−0.005 (6)	−0.004 (6)
C9	0.012 (7)	0.031 (8)	0.018 (7)	0.005 (5)	−0.012 (5)	−0.005 (6)
C10	0.015 (6)	0.013 (6)	0.017 (7)	0.010 (5)	0.003 (5)	0.004 (6)
C11	0.014 (6)	0.012 (7)	0.020 (7)	−0.005 (5)	−0.007 (5)	0.003 (5)
C12	0.013 (7)	0.022 (7)	0.018 (7)	0.003 (5)	0.002 (5)	0.010 (6)
C13	0.010 (6)	0.021 (6)	0.023 (8)	0.000 (5)	−0.005 (5)	−0.003 (6)
C14	0.016 (6)	0.022 (7)	0.031 (8)	0.000 (5)	−0.003 (5)	0.003 (6)
C15	0.039 (8)	0.024 (7)	0.047 (9)	−0.001 (7)	−0.017 (7)	0.007 (8)

Geometric parameters (Å, º) top

Pt1—Cl1	2.360 (3)	C6—H6	0.9300
Pt1—Cl2	2.329 (3)	C7—H7A	0.9700
Pt1—S1	2.266 (3)	C7—H7B	0.9700
Pt1—C11	1.968 (12)	C7—C8	1.533 (18)
S1—C1	1.786 (12)	C8—H8A	0.9700
S1—C7	1.834 (12)	C8—H8B	0.9700
N1—C10	1.390 (15)	C9—H9	0.9300
N1—C11	1.343 (15)	C9—C10	1.349 (17)
N1—C12	1.474 (15)	C10—H10	0.9300
N2—C8	1.465 (15)	C12—H12A	0.9700
N2—C9	1.393 (14)	C12—H12B	0.9700
N2—C11	1.360 (14)	C12—C13	1.513 (17)
C1—C2	1.388 (17)	C13—H13A	0.9700
C1—C6	1.385 (17)	C13—H13B	0.9700
C2—H2	0.9300	C13—C14	1.532 (16)
C2—C3	1.394 (16)	C14—H14A	0.9700
C3—H3	0.9300	C14—H14B	0.9700
C3—C4	1.383 (19)	C14—C15	1.507 (18)
C4—H4	0.9300	C15—H15A	0.9600
C4—C5	1.383 (19)	C15—H15B	0.9600
C5—H5	0.9300	C15—H15C	0.9600
C5—C6	1.388 (19)

Cl2—Pt1—Cl1	90.54 (11)	N2—C8—C7	109.9 (10)
S1—Pt1—Cl1	87.93 (11)	N2—C8—H8A	109.7
S1—Pt1—Cl2	174.77 (11)	N2—C8—H8B	109.7
C11—Pt1—Cl1	179.0 (4)	C7—C8—H8A	109.7
C11—Pt1—Cl2	90.4 (4)	C7—C8—H8B	109.7
C11—Pt1—S1	91.1 (4)	H8A—C8—H8B	108.2
C1—S1—Pt1	108.5 (4)	N2—C9—H9	127.0
C1—S1—C7	101.4 (6)	C10—C9—N2	106.0 (10)
C7—S1—Pt1	109.2 (4)	C10—C9—H9	127.0
C10—N1—C12	123.6 (10)	N1—C10—H10	126.1
C11—N1—C10	110.1 (10)	C9—C10—N1	107.7 (10)
C11—N1—C12	125.9 (9)	C9—C10—H10	126.1
C9—N2—C8	126.2 (9)	N1—C11—Pt1	131.4 (8)
C11—N2—C8	123.2 (9)	N1—C11—N2	105.7 (9)
C11—N2—C9	110.5 (10)	N2—C11—Pt1	122.8 (8)
C2—C1—S1	122.8 (9)	N1—C12—H12A	109.5
C6—C1—S1	116.6 (10)	N1—C12—H12B	109.5
C6—C1—C2	120.7 (12)	N1—C12—C13	110.8 (10)
C1—C2—H2	120.5	H12A—C12—H12B	108.1
C1—C2—C3	118.9 (12)	C13—C12—H12A	109.5
C3—C2—H2	120.5	C13—C12—H12B	109.5
C2—C3—H3	119.7	C12—C13—H13A	109.0
C4—C3—C2	120.7 (12)	C12—C13—H13B	109.0
C4—C3—H3	119.7	C12—C13—C14	112.7 (10)
C3—C4—H4	120.1	H13A—C13—H13B	107.8
C3—C4—C5	119.8 (12)	C14—C13—H13A	109.0
C5—C4—H4	120.1	C14—C13—H13B	109.0
C4—C5—H5	119.9	C13—C14—H14A	109.3
C4—C5—C6	120.2 (13)	C13—C14—H14B	109.3
C6—C5—H5	119.9	H14A—C14—H14B	108.0
C1—C6—C5	119.7 (12)	C15—C14—C13	111.7 (11)
C1—C6—H6	120.2	C15—C14—H14A	109.3
C5—C6—H6	120.2	C15—C14—H14B	109.3
S1—C7—H7A	109.3	C14—C15—H15A	109.5
S1—C7—H7B	109.3	C14—C15—H15B	109.5
H7A—C7—H7B	107.9	C14—C15—H15C	109.5
C8—C7—S1	111.8 (8)	H15A—C15—H15B	109.5
C8—C7—H7A	109.3	H15A—C15—H15C	109.5
C8—C7—H7B	109.3	H15B—C15—H15C	109.5

Pt1—S1—C1—C2	62.3 (11)	C8—N2—C9—C10	175.0 (11)
Pt1—S1—C1—C6	−118.3 (9)	C8—N2—C11—Pt1	3.2 (16)
Pt1—S1—C7—C8	14.3 (10)	C8—N2—C11—N1	−174.1 (10)
S1—C1—C2—C3	−177.4 (10)	C9—N2—C8—C7	−108.8 (12)
S1—C1—C6—C5	178.0 (10)	C9—N2—C11—Pt1	178.8 (8)
S1—C7—C8—N2	−67.4 (11)	C9—N2—C11—N1	1.5 (14)
N1—C12—C13—C14	−171.7 (10)	C10—N1—C11—Pt1	−179.0 (10)
N2—C9—C10—N1	−0.9 (13)	C10—N1—C11—N2	−2.0 (14)
C1—S1—C7—C8	128.8 (9)	C10—N1—C12—C13	86.3 (13)
C1—C2—C3—C4	−2 (2)	C11—N1—C10—C9	1.8 (14)
C2—C1—C6—C5	−2.5 (19)	C11—N1—C12—C13	−85.0 (14)
C2—C3—C4—C5	0 (2)	C11—N2—C8—C7	66.0 (14)
C3—C4—C5—C6	1 (2)	C11—N2—C9—C10	−0.4 (14)
C4—C5—C6—C1	0 (2)	C12—N1—C10—C9	−170.7 (11)
C6—C1—C2—C3	3.2 (19)	C12—N1—C11—Pt1	−6.7 (19)
C7—S1—C1—C2	−52.6 (11)	C12—N1—C11—N2	170.3 (10)
C7—S1—C1—C6	126.8 (10)	C12—C13—C14—C15	179.8 (10)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the N1/C10/C9/N2/C11 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9···Cl2ⁱ	0.93	2.58	3.485 (12)	163
C2—H2···Cg1	0.93	2.98	3.828 (13)	151
C14—H14A···Cg1ⁱⁱ	0.97	2.82	3.480 (13)	126

Symmetry codes: (i) x−1, y, z; (ii) −x+1, y+1/2, −z+1/2.

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