Crystal structure and Hirshfeld surface analysis of bis­[(eth­oxy­methane­thio­yl)sulfanido](N,N,N′,N′-tetra­methyl­ethane-1,2-di­amine)­mercury(II)

Qadir, A.M.; Kansiz, S.; Dege, N.; Saif, E.

doi:10.1107/S2056989021010549

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Volume 77| Part 11| November 2021| Pages 1126-1129

https://doi.org/10.1107/S2056989021010549

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Crystal structure and Hirshfeld surface analysis of bis[(ethoxymethanethioyl)sulfanido](N,N,N′,N′-tetramethylethane-1,2-diamine)mercury(II)

Adnan M. Qadir,^a Sevgi Kansiz,^b ^* Necmi Dege ^c and Eiad Saif ^d,^e ^*

^aDepartment of Chemistry, College of Science, Salahaddin University, Erbil, 44001, Iraq, ^bSamsun University, Faculty of Engineering, Department of Fundamental Sciences, 55420, Samsun, Turkey, ^cOndokuz Mayıs University, Faculty of Arts and Sciences, Department of Physics, 55139, Samsun, Turkey, ^dDepartment of Computer and Electronic Engineering Technology, Sanaa Community College, Sanaa, Yemen, and ^eDepartment of Electrical and Electronic Engineering, Faculty of Engineering, Ondokuz Mayıs University, 55139, Samsun, Turkey
^*Correspondence e-mail: sevgi.kansiz@samsun.edu.tr, eiad.saif@scc.edu.ye

Edited by D. Gray, University of Illinois Urbana-Champaign, USA (Received 28 May 2021; accepted 11 October 2021; online 19 October 2021)

The title four-coordinate mononuclear complex, [Hg(C₃H₅OS₂)₂(C₆H₁₆N₂)] or [Hg(C₃H₅OS₂)₂(tmeda)] (tmeda: N,N,N′,N′-tetramethylethane-1,2-diamine), has a distorted tetrahedral geometry. The Hg^II ion is coordinated to two N atoms of the N,N,N′,N′-tetramethylethylenediamine ligand and two S atoms from two ethylxanthate xanthate ligands. In the crystal, molecules are linked by weak C—H⋯S hydrogen bonds, forming a two-dimensional supramolecular architecture in the ab plane. The most important contributions for the crystal packing are from H⋯H (59.3%), S⋯H (27.4%) and O⋯H (7.5%) interactions.

Keywords: crystal structure; xanthate; mercury(II); Hirshfeld surface analysis.

CCDC reference: 2115100

1. Chemical context

Xanthates (dithiocarbonates) attract the interest of many researchers in the field of coordination chemistry owing to their antidotal, antioxidant and antitumor activities (Shahzadi et al., 2009 ; Perluigi et al., 2006 ; Larsson & Oberg, 2011 ). These ligands exhibit different coordination modes such as monodentate, isobidentate or anisobidentate. Cellulose xanthate has been used for the separation of alcohols by the chromatographic method (Friebolin et al., 2004 ). It has been reported that metal xanthates exhibit cytotoxic activity on human cancer cells and have the ability to inhibit both DNA and RNA viruses in vitro (Efrima & Pradhan, 2003 ). Mercury represents one of the most toxic heavy metals found in solid and liquid waste from oil refineries and the mining industry. We report herein the synthesis and crystal structure of a new Hg^II xanthate containing N,N,N′,N′-tetramethylethylenediamine, including the results of a Hirshfeld surface analysis.

2. Structural commentary

The asymmetric unit of the title complex (Fig. 1) comprises one Hg^II ion, one half N,N,N′,N′-tetramethylethylenediamine ligand and one ethylxanthate ligand. The Hg^II ion is coordinated by two N atoms of the N,N,N′,N′-tetramethylethylenediamine ligand and two S atoms from two ethylxanthate xanthate ligands in a distorted tetrahedral environment. The Hg—N and Hg—S bond lengths (Table 1) are 2.531 (8) and 2.416 (3) Å, respectively, whereas the bond angles around the central Hg^II ion are in the range 73.8 (3)–149.91 (18)°. The bond lengths and angles of the HgN₂S₂ coordination units correspond to those in the structures of mixed-ligand Hg^II coordination compounds (see Database survey). The C1—O1 and C2—O1 bond lengths are 1.355 (11) to 1.460 (12) Å, respectively, although all of the C—O bonds show single-bond character. In the {S₂C} section of the xanthate ligands, the C1—S1 distance is 1.727 (9) Å, which is typical of a single bond, whereas the C1=S2 distance of 1.633 (10) Å is typical of a carbon-to-sulfur double bond. The C—N and C—C bond lengths in the N,N,N′,N′-tetramethylethylenediamine ligand are normal (Qadir et al., 2020 ).

Table 1
Selected bond lengths (Å)

Hg1—S1	2.416 (3)	O1—C1	1.355 (11)
Hg1—N1	2.531 (8)	O1—C2	1.460 (12)
S1—C1	1.727 (9)	N1—C5	1.452 (13)
S2—C1	1.633 (10)	N1—C4	1.479 (13)

Figure 1
The molecular structure of [Hg(C₃H₅S₂O₁)₂(tmeda)], with the atom labelling. Displacement ellipsoids are drawn at the 30% probability level. Symmetry code: (i) −x + 1, y, −z + $[{3\over 2}]$ .

3. Supramolecular features

In the crystal, there is a weak intermolecular hydrogen bonding (Table 2) between S atoms and the H atoms of the methylene groups [C4—H4B⋯S1 (x − $[{1\over 2}]$ , y − $[{1\over 2}]$ , −z + $[{3\over 2}]$ )]. Fig. 2 illustrates the two-dimensional wave-like structure extending in the ab plane formed by hydrogen-bonding interactions in [Hg(C₃H₅S₂O₁)₂(tmeda)].

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4B⋯S1ⁱ	0.97	2.92	3.845 (11)	160
Symmetry code: (i) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 2
Two-dimensional wave-like structure extending in the ab plane formed by hydrogen-bonding interactions in [Hg(C₃H₅S₂O₁)₂(tmeda)].

4. Database survey

A search of the Cambridge Structural Database (CSD, version 5.42, update of November 2020; Groom et al., 2016 ) for the title complex revealed five similar complexes: [Hg(C₁₄H₂₆O₂S₄)]_n (BATXOJ; Cox & Tiekink, 1999 ), [Hg(C₅H₄NSe)₂(C₆H₁₆N₂)] (EKODAK; Sharma et al., 2011 ), [Hg(C₆H₁₆N₂)(C₉H₁₃NS)₂](PF₆)₂ (POTJOY; Tang et al., 2009 ), [HgCl(C₇H₇S)(C₆H₁₆N₂)_] (TEVQAM; Kräuter et al., 1996 ) and [HgCl₂(C₆H₁₆N₂)] (ZZZAJM; Htoon & Ladd, 1976 ). In BATXOJ, the coordination geometry is distorted tetrahedral with the independent Hg—S distances being 2.413 (5) and 2.842 (5) Å. The range of S—Hg—S angles is 81.8 (2)–150.8 (3)° with the wider angle involving the more tightly bound S1 atoms. In EKODAK, the corresponding mercury complex adopts a severely distorted tetrahedral configuration defined by the two monodentate selenolate and chelating tmeda ligands. The Hg—N bond lengths are in the range 2.573 (17)–2.601 (18) Å. In POTJOY, intermolecular C—H⋯S hydrogen bonds are important in the crystal packing. Similarly, the molecules are connected to each other via C—H⋯S hydrogen bonds in the title complex. In TEVQAM, the Hg—N and Hg—S bond lengths are 2.54 and 2.34 Å, respectively, comparable to those in the title compound.

5. Hirshfeld surface analysis

A Hirshfeld surface analysis (Spackman & Jayatilaka, 2009 ) was carried out using CrystalExplorer17.5 (Turner et al., 2017 ) to quantify the various intermolecular interactions. The Hirshfeld surface mapped over d_norm is illustrated in Fig. 3 and the associated two-dimensional fingerprint plots in Fig. 4. The major contributions to the crystal structure are from H⋯H (59.3%), S⋯H (27.4%) and O⋯H interactions (7.5%. The large number of H⋯H interactions suggest that van der Waals interactions and hydrogen bonding play the major roles in the crystal packing. C⋯H (3.4%) and S⋯O (1.9%) contacts are also observed.

Figure 3
Hirshfeld surface mapped with d_norm.

Figure 4
Two-dimensional fingerprint plots for [Hg(C₃H₅S₂O₁)₂(tmeda)].

6. Synthesis and crystallization

Potassium ethylxanthate (4 mmol, 0.64 g) in hot ethanol (10 mL) was added to a hot solution of Hg(CH₃CO₂)₂ (2 mmol, 0.64 g) in ethanol (10 mL) under stirring. The formed precipitate was filtered off, washed with water and air-dried. The precipitate was suspended in hot ethanol (10 mL) and tetramethylethylenediamine (2 mmol, 0.23 g) was added under stirring. The colour changed to dark brown. The precipitate was filtered off and dried and then recrystallized from ethanol. Brown rods were formed.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3. C-bound H atoms were positioned geometrically (C—H = 0.96 and 0.97 Å) and refined using a riding model, with U_iso(H) = 1.5U_eq(C) for methyl H atoms and 1.2U_eq(C) for all others

Table 3
Experimental details

Crystal data
Chemical formula	[Hg(C₃H₅OS₂)₂(C₆H₁₆N₂)]
M_r	559.18
Crystal system, space group	Orthorhombic, Pbcn
Temperature (K)	296
a, b, c (Å)	12.235 (7), 8.017 (5), 21.251 (17)
V (Å³)	2084 (2)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	7.79
Crystal size (mm)	0.71 × 0.38 × 0.06

Data collection
Diffractometer	Bruker D8 Quest with Photon II CPADs detector
Absorption correction	Multi-scan (SADABS; Krause et al., 2015 )
T_min, T_max	0.041, 0.627
No. of measured, independent and observed [I > 2σ(I)] reflections	8974, 1946, 1265
R_int	0.139
(sin θ/λ)_max (Å⁻¹)	0.610

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.053, 0.147, 1.00
No. of reflections	1946
No. of parameters	99
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.01, −2.73
Computer programs: APEX3 and SAINT (Bruker, 2017 ), SHELXT2018/2 (Sheldrick, 2015a ), SHELXL2017/1 (Sheldrick, 2015b ), PLATON (Spek, 2020 ) and WinGX (Farrugia, 2012 ).

Supporting information

CCDC reference: 2115100

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989021010549/ey2008sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989021010549/ey2008Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2017); cell refinement: SAINT (Bruker, 2017); data reduction: SAINT (Bruker, 2017); program(s) used to solve structure: SHELXT2018/2 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017/1 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2020); software used to prepare material for publication: WinGX (Farrugia, 2012).

Bis[(ethoxymethanethioyl)sulfanido](N,N,N',N'-\ tetramethylethane-1,2-diamine)mercury(II) top

Crystal data top

[Hg(C₃H₅OS₂)₂(C₆H₁₆N₂)]	D_x = 1.782 Mg m⁻³
M_r = 559.18	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pbcn	Cell parameters from 379 reflections
a = 12.235 (7) Å	θ = 2.0–24.7°
b = 8.017 (5) Å	µ = 7.79 mm⁻¹
c = 21.251 (17) Å	T = 296 K
V = 2084 (2) Å³	Rod, brown
Z = 4	0.71 × 0.38 × 0.06 mm
F(000) = 1088

Data collection top

Bruker D8 Quest with Photon II CPADs detector diffractometer	1946 independent reflections
Radiation source: Incoatec microfocus source	1265 reflections with I > 2σ(I)
Detector resolution: 7.4074 pixels mm^-1	R_int = 0.139
phi and ω scans	θ_max = 25.7°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	h = −14→12
T_min = 0.041, T_max = 0.627	k = −6→9
8974 measured reflections	l = −25→25

Refinement top

Refinement on F²	Primary atom site location: dual
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.053	H-atom parameters constrained
wR(F²) = 0.147	w = 1/[σ²(F_o²) + (0.0768P)²] where P = (F_o² + 2F_c²)/3
S = 1.00	(Δ/σ)_max < 0.001
1946 reflections	Δρ_max = 1.01 e Å⁻³
99 parameters	Δρ_min = −2.73 e Å⁻³
0 restraints

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
Hg1	0.500000	0.59649 (6)	0.750000	0.0605 (2)
S1	0.6620 (2)	0.6747 (4)	0.69202 (12)	0.0807 (9)
S2	0.4722 (2)	0.7975 (5)	0.61444 (14)	0.0815 (8)
O1	0.6840 (6)	0.8337 (10)	0.5917 (3)	0.0753 (19)
N1	0.4366 (6)	0.3441 (10)	0.6885 (3)	0.0580 (18)
C1	0.6025 (8)	0.7760 (12)	0.6290 (4)	0.063 (2)
C6	0.5057 (9)	0.3204 (18)	0.6319 (5)	0.087 (4)
H6A	0.502245	0.418481	0.606101	0.131*
H6B	0.479686	0.226095	0.608454	0.131*
H6C	0.579968	0.301191	0.644595	0.131*
C4	0.4462 (8)	0.1997 (13)	0.7314 (5)	0.069 (2)
H4A	0.441367	0.097608	0.707118	0.083*
H4B	0.385492	0.201216	0.760778	0.083*
C3	0.7614 (16)	0.9572 (16)	0.5016 (5)	0.101 (5)
H3A	0.747525	1.015326	0.462895	0.152*
H3B	0.795996	0.852358	0.492616	0.152*
H3C	0.808505	1.023299	0.527706	0.152*
C5	0.3232 (9)	0.3668 (17)	0.6701 (5)	0.090 (4)
H5A	0.280086	0.390950	0.706757	0.136*
H5B	0.296750	0.266672	0.650617	0.136*
H5C	0.317899	0.457818	0.640942	0.136*
C2	0.6563 (11)	0.9271 (15)	0.5349 (5)	0.091 (4)
H2A	0.621592	1.031988	0.545653	0.109*
H2B	0.606886	0.863221	0.508546	0.109*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg1	0.0589 (4)	0.0689 (4)	0.0536 (3)	0.000	0.0023 (2)	0.000
S1	0.0618 (15)	0.113 (2)	0.0676 (13)	−0.0248 (17)	−0.0088 (11)	0.0231 (15)
S2	0.0674 (17)	0.096 (2)	0.0811 (16)	0.0098 (16)	−0.0023 (13)	0.0141 (16)
O1	0.082 (5)	0.085 (5)	0.059 (3)	−0.011 (4)	0.009 (3)	0.013 (3)
N1	0.056 (5)	0.064 (5)	0.054 (4)	0.000 (4)	0.002 (3)	0.000 (3)
C1	0.075 (6)	0.059 (6)	0.056 (5)	−0.015 (5)	0.004 (4)	0.000 (4)
C6	0.103 (9)	0.088 (9)	0.071 (6)	−0.008 (8)	0.012 (5)	−0.024 (6)
C4	0.057 (6)	0.067 (6)	0.084 (6)	−0.023 (6)	−0.006 (5)	−0.010 (5)
C3	0.142 (13)	0.083 (10)	0.079 (7)	0.005 (8)	0.037 (7)	0.015 (7)
C5	0.075 (8)	0.123 (11)	0.073 (6)	−0.013 (7)	−0.019 (6)	−0.003 (6)
C2	0.115 (10)	0.090 (8)	0.067 (6)	0.005 (8)	0.018 (7)	0.025 (5)

Geometric parameters (Å, º) top

Hg1—S1	2.416 (3)	C6—H6C	0.9600
Hg1—S1ⁱ	2.416 (3)	C4—C4ⁱ	1.53 (2)
Hg1—N1	2.531 (8)	C4—H4A	0.9700
Hg1—N1ⁱ	2.531 (8)	C4—H4B	0.9700
S1—C1	1.727 (9)	C3—C2	1.49 (2)
S2—C1	1.633 (10)	C3—H3A	0.9600
O1—C1	1.355 (11)	C3—H3B	0.9600
O1—C2	1.460 (12)	C3—H3C	0.9600
N1—C5	1.452 (13)	C5—H5A	0.9600
N1—C4	1.479 (13)	C5—H5B	0.9600
N1—C6	1.481 (13)	C5—H5C	0.9600
C6—H6A	0.9600	C2—H2A	0.9700
C6—H6B	0.9600	C2—H2B	0.9700

S1—Hg1—S1ⁱ	149.91 (18)	N1—C4—H4A	109.1
S1—Hg1—N1	101.26 (18)	C4ⁱ—C4—H4A	109.1
S1ⁱ—Hg1—N1	102.70 (19)	N1—C4—H4B	109.1
S1—Hg1—N1ⁱ	102.70 (19)	C4ⁱ—C4—H4B	109.1
S1ⁱ—Hg1—N1ⁱ	101.26 (18)	H4A—C4—H4B	107.8
N1—Hg1—N1ⁱ	73.8 (3)	C2—C3—H3A	109.5
C1—S1—Hg1	99.9 (3)	C2—C3—H3B	109.5
C1—O1—C2	119.2 (9)	H3A—C3—H3B	109.5
C5—N1—C4	109.8 (9)	C2—C3—H3C	109.5
C5—N1—C6	110.1 (8)	H3A—C3—H3C	109.5
C4—N1—C6	110.8 (9)	H3B—C3—H3C	109.5
C5—N1—Hg1	109.3 (7)	N1—C5—H5A	109.5
C4—N1—Hg1	106.4 (5)	N1—C5—H5B	109.5
C6—N1—Hg1	110.3 (6)	H5A—C5—H5B	109.5
O1—C1—S2	124.9 (7)	N1—C5—H5C	109.5
O1—C1—S1	107.7 (7)	H5A—C5—H5C	109.5
S2—C1—S1	127.4 (5)	H5B—C5—H5C	109.5
N1—C6—H6A	109.5	O1—C2—C3	106.0 (11)
N1—C6—H6B	109.5	O1—C2—H2A	110.5
H6A—C6—H6B	109.5	C3—C2—H2A	110.5
N1—C6—H6C	109.5	O1—C2—H2B	110.5
H6A—C6—H6C	109.5	C3—C2—H2B	110.5
H6B—C6—H6C	109.5	H2A—C2—H2B	108.7
N1—C4—C4ⁱ	112.7 (7)

C2—O1—C1—S2	1.9 (13)	C5—N1—C4—C4ⁱ	−162.2 (10)
C2—O1—C1—S1	−179.2 (8)	C6—N1—C4—C4ⁱ	75.9 (12)
Hg1—S1—C1—O1	178.2 (6)	Hg1—N1—C4—C4ⁱ	−44.0 (11)
Hg1—S1—C1—S2	−3.0 (7)	C1—O1—C2—C3	−174.4 (9)

Symmetry code: (i) −x+1, y, −z+3/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4B···S1ⁱⁱ	0.97	2.92	3.845 (11)	160

Symmetry code: (ii) x−1/2, y−1/2, −z+3/2.

Acknowledgements

Author contributions are as follows. Conceptualization, SK, AMQ and ES; synthesis, AMQ; writing (review and editing of the manuscript), SK and AMQ, formal analysis, SK, AMQ and ND, validation, SK, AMQ and ND, project administration, SK, AMQ and ES.

Funding information

Funding for this research was provided by: Ondokuz Mayıs University under Project No. PYO.FEN.1906.19.001.

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