Crystal structure of di­chlorido­bis­­(1,3,4,5-tetra­methyl-1H-imidazol-2-ium-2-thiol­ate-κS)nickel(II)

In the mol­ecular structure of the title compound, [NiCl₂(C₇H₁₂N₂S)₂], the Ni^II atom has a distorted tetra­hedral geometry, coordinated by two Cl atoms [Ni—Cl= 2.2336 (6) Å] and two thione S atoms [Ni—S= 2.3024 (6) Å]. The angles at the Ni^II cation, which lies on a twofold rotation axis, are Cl—Ni—Cl = 115.58 (3)° and S—Ni—S = 94.55 (3)°. All other angles at the central Ni^II atom range from 109.46 (2) to 112.96 (2)°. The C—S—Ni angle is 99.91 (6)°. The planes of two imidazolium rings make a dihedral angle of 70.56 (6)°.

1. Related literature

For structures of related Ni complexes, see: Flörke et al. (2014); O'Neill et al. (1981). For the ability of N,N-di­methyl­imidazole­thione derivatives to act as effective anti-oxidants, see: Bhabak & Mugesh (2010); Yamashita & Yamashita (2010). For C—S bond lengths, see: Williams et al. (1997).

2. Experimental

2.1. Crystal data

• [NiCl₂(C₇H₁₂N₂S)₂]

• M_r = 442.10

• Monoclinic, C 2/c

• a = 14.8539 (17) Å

• b = 8.5969 (10) Å

• c = 16.4434 (19) Å

• β = 112.104 (2)°

• V = 1945.5 (4) ų

• Z = 4

• Mo Kα radiation

• μ = 1.49 mm⁻¹

• T = 120 K

• 0.43 × 0.20 × 0.14 mm

2.2. Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Sheldrick, 2004) T_min = 0.567, T_max = 0.819

• 8874 measured reflections

• 2396 independent reflections

• 2050 reflections with I > 2σ(I)

• R_int = 0.033

2.3. Refinement

• R[F² > 2σ(F²)] = 0.035

• wR(F²) = 0.089

• S = 1.09

• 2396 reflections

• 109 parameters

• H-atom parameters constrained

• Δρ_max = 0.56 e Å⁻³

• Δρ_min = −0.27 e Å⁻³

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Supporting information

S1. Structural commentary

We are inter­ested in the chemistry of N,N-di­methyl­imidazole-thione derivatives due to their ability to act as effective anti­oxidants Bhabak et al. (2010); Yamashita et al. (2010). Complexes of the l-methyl derivative of imidazoline-2-thione with Zn(II) and Ni^II have been previously reported Flörke et al. (2014); O Neill et al., (1981). In our group we are inter­ested in this type of compound to be used in the synthesis of biomimetic complexes. Here we report the synthesis of Ni^II chloride complex with 1,3,4,5-tetra-methyl­imidazole-2-thione ligands. The title compound shows the same trans configuration as the di­chloro­biis(1,3-diiso­propyl-methyl-1H-2H.imidazole-2-thione-S)zinc(II) (Flörke et al., 2014). The Ni atom shows a distorted tetra­hedron with two chlorine atoms and two thione ligands, in which the angles at the Nickel cation are Cl—Ni—Cl 115.57 (3)° and S—Ni—S 94.55 (3)° . All other angles at the central Ni atom range from 109.46 (2)° to 112.96 (2)°. The Ni—S bond length is 2.2336 (6) Å. The C—S bond length in the title compound is elongated to 1.719 (2)Å by coordination to Nickel and closer to a single bond 1.81Å than a double bond 1.56Å (Williams et al., 1997). The intra­molecular hydrogen bonds between the chlorine atom and hydrogen atoms of methyl group, H2a—-Cl and H7b—-Cl amount to 3.093 and 3.557.respectively.

S2. Synthesis and crystallization

To a solution of 1,3,4,5-tetra-methyl­imidazoline-2-thione (0.390mg, 2.75mmol) in 40 ml aceto­nitrile, NiCl₂ (0.162 mg, 1.25 mmol) ) was added and the mixture was stirred at room temperature for 24h. After removal of the solvent and subsequent drying in vacuum the residue was crystallized by diffusion of di­ethyl ether into a concentrated aceto­nitrile solution to give green single-crystals of the title complex.

S3. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. All H-atoms were clearly identified in difference syntheses and then refined at idealized positions riding on the carbon atoms with isotropic displacement parameters Uiso(H) = 1.5U(-CH₃) and C–H 0.98 Å. All CH₃ hydrogen atoms were allowed to rotate but not to tip.

Related literature

For structures of related Ni complexes, see: Flörke et al. (2014); O'Neill et al. (1981). For the ability of N,N-dimethylimidazolethione derivatives to act as effective anti-oxidants, see: Bhabak & Mugesh (2010); Yamashita & Yamashita (2010). For C—S bond lengths, see: Williams et al. (1997).

Structure description

We are inter­ested in the chemistry of N,N-di­methyl­imidazole-thione derivatives due to their ability to act as effective anti­oxidants Bhabak et al. (2010); Yamashita et al. (2010). Complexes of the l-methyl derivative of imidazoline-2-thione with Zn(II) and Ni^II have been previously reported Flörke et al. (2014); O Neill et al., (1981). In our group we are inter­ested in this type of compound to be used in the synthesis of biomimetic complexes. Here we report the synthesis of Ni^II chloride complex with 1,3,4,5-tetra-methyl­imidazole-2-thione ligands. The title compound shows the same trans configuration as the di­chloro­biis(1,3-diiso­propyl-methyl-1H-2H.imidazole-2-thione-S)zinc(II) (Flörke et al., 2014). The Ni atom shows a distorted tetra­hedron with two chlorine atoms and two thione ligands, in which the angles at the Nickel cation are Cl—Ni—Cl 115.57 (3)° and S—Ni—S 94.55 (3)° . All other angles at the central Ni atom range from 109.46 (2)° to 112.96 (2)°. The Ni—S bond length is 2.2336 (6) Å. The C—S bond length in the title compound is elongated to 1.719 (2)Å by coordination to Nickel and closer to a single bond 1.81Å than a double bond 1.56Å (Williams et al., 1997). The intra­molecular hydrogen bonds between the chlorine atom and hydrogen atoms of methyl group, H2a—-Cl and H7b—-Cl amount to 3.093 and 3.557.respectively.

For structures of related Ni complexes, see: Flörke et al. (2014); O'Neill et al. (1981). For the ability of N,N-dimethylimidazolethione derivatives to act as effective anti-oxidants, see: Bhabak & Mugesh (2010); Yamashita & Yamashita (2010). For C—S bond lengths, see: Williams et al. (1997).

Synthesis and crystallization

To a solution of 1,3,4,5-tetra-methyl­imidazoline-2-thione (0.390mg, 2.75mmol) in 40 ml aceto­nitrile, NiCl₂ (0.162 mg, 1.25 mmol) ) was added and the mixture was stirred at room temperature for 24h. After removal of the solvent and subsequent drying in vacuum the residue was crystallized by diffusion of di­ethyl ether into a concentrated aceto­nitrile solution to give green single-crystals of the title complex.

Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 1. All H-atoms were clearly identified in difference syntheses and then refined at idealized positions riding on the carbon atoms with isotropic displacement parameters Uiso(H) = 1.5U(-CH₃) and C–H 0.98 Å. All CH₃ hydrogen atoms were allowed to rotate but not to tip.

Computing details

Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and local programs.

Figures

Fig. 1. Molecular structure of the title compound with anisotropic displacement parameters drawn at the 50% probability level.

Dichloridobis(1,3,4,5-tetramethyl-1H-imidazol-2-ium-2-thiolate-κS)nickel(II)

Crystal data

[NiCl2(C7H12N2S)2]	F(000) = 920
Mr = 442.10	Dx = 1.509 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 14.8539 (17) Å	Cell parameters from 2710 reflections
b = 8.5969 (10) Å	θ = 2.7–28.3°
c = 16.4434 (19) Å	µ = 1.49 mm^−1
β = 112.104 (2)°	T = 120 K
V = 1945.5 (4) Å^3	Prism, green
Z = 4	0.43 × 0.20 × 0.14 mm

Data collection

Bruker SMART CCD area-detector diffractometer	2396 independent reflections
Radiation source: sealed tube	2050 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.033
φ and ω scans	θmax = 28.2°, θmin = 2.8°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −19→19
Tmin = 0.567, Tmax = 0.819	k = −11→10
8874 measured reflections	l = −21→21

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: difference Fourier map
wR(F^2) = 0.089	H-atom parameters constrained
S = 1.09	w = 1/[σ^2(Fo^2) + (0.0492P)^2 + 0.3156P] where P = (Fo^2 + 2Fc^2)/3
2396 reflections	(Δ/σ)max < 0.001
109 parameters	Δρmax = 0.56 e Å^−3
0 restraints	Δρmin = −0.27 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ni1	0.0000	0.47837 (4)	0.2500	0.02273 (12)
Cl1	0.05106 (4)	0.61687 (7)	0.16067 (3)	0.03670 (15)
S1	0.11606 (3)	0.29666 (6)	0.32329 (3)	0.02693 (14)
N1	0.22435 (11)	0.46213 (18)	0.46966 (10)	0.0225 (3)
N2	0.27871 (11)	0.48030 (18)	0.36568 (10)	0.0235 (3)
C1	0.20753 (13)	0.4178 (2)	0.38685 (12)	0.0222 (4)
C2	0.16219 (14)	0.4241 (3)	0.51751 (13)	0.0292 (4)
H2A	0.1144	0.5072	0.5092	0.044*
H2B	0.2020	0.4135	0.5801	0.044*
H2C	0.1283	0.3259	0.4954	0.044*
C3	0.30709 (13)	0.5538 (2)	0.50124 (12)	0.0237 (4)
C4	0.34399 (15)	0.6198 (2)	0.59158 (12)	0.0305 (4)
H4A	0.3994	0.6881	0.5993	0.046*
H4B	0.3646	0.5351	0.6345	0.046*
H4C	0.2923	0.6798	0.6004	0.046*
C5	0.34120 (13)	0.5658 (2)	0.43585 (12)	0.0250 (4)
C6	0.42680 (14)	0.6509 (3)	0.43159 (14)	0.0338 (5)
H6A	0.4624	0.7006	0.4883	0.051*
H6B	0.4046	0.7306	0.3857	0.051*
H6C	0.4697	0.5776	0.4180	0.051*
C7	0.28996 (15)	0.4587 (3)	0.28167 (13)	0.0306 (5)
H7A	0.3421	0.3837	0.2890	0.046*
H7B	0.3063	0.5585	0.2619	0.046*
H7C	0.2290	0.4196	0.2380	0.046*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.02009 (19)	0.0228 (2)	0.02449 (19)	0.000	0.00747 (14)	0.000
Cl1	0.0332 (3)	0.0404 (3)	0.0408 (3)	0.0038 (2)	0.0189 (2)	0.0134 (2)
S1	0.0247 (2)	0.0242 (3)	0.0280 (3)	0.00122 (18)	0.00545 (19)	0.00048 (18)
N1	0.0203 (7)	0.0249 (9)	0.0229 (8)	0.0024 (6)	0.0087 (6)	0.0042 (6)
N2	0.0219 (8)	0.0263 (9)	0.0227 (8)	0.0042 (6)	0.0086 (6)	0.0054 (6)
C1	0.0209 (8)	0.0233 (10)	0.0228 (9)	0.0049 (7)	0.0085 (7)	0.0055 (7)
C2	0.0271 (10)	0.0386 (12)	0.0262 (10)	0.0002 (8)	0.0150 (8)	0.0044 (8)
C3	0.0219 (9)	0.0223 (10)	0.0260 (9)	0.0022 (7)	0.0078 (7)	0.0047 (7)
C4	0.0337 (11)	0.0298 (11)	0.0270 (10)	−0.0017 (8)	0.0101 (8)	0.0010 (8)
C5	0.0219 (9)	0.0253 (10)	0.0260 (9)	0.0015 (7)	0.0071 (7)	0.0057 (8)
C6	0.0275 (10)	0.0394 (12)	0.0354 (11)	−0.0042 (9)	0.0130 (8)	0.0091 (9)
C7	0.0314 (11)	0.0398 (12)	0.0247 (10)	0.0059 (9)	0.0153 (8)	0.0041 (9)

Geometric parameters (Å, º)

Ni1—Cl1	2.2336 (6)	C2—H2C	0.9800
Ni1—Cl1^i	2.2337 (6)	C3—C5	1.354 (3)
Ni1—S1^i	2.3024 (6)	C3—C4	1.489 (3)
Ni1—S1	2.3024 (6)	C4—H4A	0.9800
S1—C1	1.719 (2)	C4—H4B	0.9800
N1—C1	1.344 (2)	C4—H4C	0.9800
N1—C3	1.386 (2)	C5—C6	1.492 (3)
N1—C2	1.458 (2)	C6—H6A	0.9800
N2—C1	1.343 (2)	C6—H6B	0.9800
N2—C5	1.388 (2)	C6—H6C	0.9800
N2—C7	1.464 (2)	C7—H7A	0.9800
C2—H2A	0.9800	C7—H7B	0.9800
C2—H2B	0.9800	C7—H7C	0.9800
Cl1—Ni1—Cl1^i	115.58 (3)	C5—C3—C4	131.00 (18)
Cl1—Ni1—S1^i	112.96 (2)	N1—C3—C4	122.16 (17)
Cl1^i—Ni1—S1^i	109.46 (2)	C3—C4—H4A	109.5
Cl1—Ni1—S1	109.46 (2)	C3—C4—H4B	109.5
Cl1^i—Ni1—S1	112.96 (2)	H4A—C4—H4B	109.5
S1^i—Ni1—S1	94.55 (3)	C3—C4—H4C	109.5
C1—S1—Ni1	99.91 (6)	H4A—C4—H4C	109.5
C1—N1—C3	109.97 (16)	H4B—C4—H4C	109.5
C1—N1—C2	124.69 (16)	C3—C5—N2	106.67 (17)
C3—N1—C2	125.30 (17)	C3—C5—C6	130.91 (18)
C1—N2—C5	109.99 (16)	N2—C5—C6	122.42 (18)
C1—N2—C7	125.03 (17)	C5—C6—H6A	109.5
C5—N2—C7	124.97 (17)	C5—C6—H6B	109.5
N2—C1—N1	106.54 (16)	H6A—C6—H6B	109.5
N2—C1—S1	127.15 (14)	C5—C6—H6C	109.5
N1—C1—S1	126.23 (15)	H6A—C6—H6C	109.5
N1—C2—H2A	109.5	H6B—C6—H6C	109.5
N1—C2—H2B	109.5	N2—C7—H7A	109.5
H2A—C2—H2B	109.5	N2—C7—H7B	109.5
N1—C2—H2C	109.5	H7A—C7—H7B	109.5
H2A—C2—H2C	109.5	N2—C7—H7C	109.5
H2B—C2—H2C	109.5	H7A—C7—H7C	109.5
C5—C3—N1	106.84 (16)	H7B—C7—H7C	109.5
Cl1^i—Ni1—S1—C1	−63.57 (7)	C1—N1—C3—C5	0.2 (2)
Cl1—Ni1—S1—C1	66.74 (7)	C2—N1—C3—C5	−177.55 (18)
S1^i—Ni1—S1—C1	−176.95 (7)	C1—N1—C3—C4	−179.83 (17)
C5—N2—C1—N1	−0.2 (2)	C2—N1—C3—C4	2.4 (3)
C7—N2—C1—N1	178.56 (17)	N1—C3—C5—N2	−0.3 (2)
C5—N2—C1—S1	−177.22 (14)	C4—C3—C5—N2	179.72 (19)
C7—N2—C1—S1	1.6 (3)	N1—C3—C5—C6	179.12 (19)
C3—N1—C1—N2	0.0 (2)	C4—C3—C5—C6	−0.9 (4)
C2—N1—C1—N2	177.77 (17)	C1—N2—C5—C3	0.3 (2)
C3—N1—C1—S1	177.06 (14)	C7—N2—C5—C3	−178.45 (18)
C2—N1—C1—S1	−5.2 (3)	C1—N2—C5—C6	−179.15 (17)
Ni1—S1—C1—N2	−89.72 (16)	C7—N2—C5—C6	2.1 (3)
Ni1—S1—C1—N1	93.84 (16)

Symmetry code: (i) −x, y, −z+1/2.