Hexa­kis­(N,N′-dimethyl­thio­urea-κS)nickel(II) nitrate

Asif, I.; Mahmood, R.; Stoeckli-Evans, H.; Mateen, M.; Ahmad, S.

doi:10.1107/S1600536810040031

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 11| November 2010| Pages m1393-m1394

https://doi.org/10.1107/S1600536810040031

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Hexakis(N,N′-dimethylthiourea-κS)nickel(II) nitrate

Iram Asif,^a Rashid Mahmood,^b Helen Stoeckli-Evans,^c Muhammad Mateen ^a and Saeed Ahmad ^a ^*

^aDepartment of Chemistry, University of Engineering and Technology, Lahore 54890, Pakistan, ^bDivision of Science and Technology, University of Education, Township, Lahore, Pakistan, and ^cInstitute of Physics, University of Neuchâtel, rue Emile-Argand 11, CH-2000 Neuchâtel, Switzerland
^*Correspondence e-mail: saeed_a786@hotmail.com

(Received 3 October 2010; accepted 7 October 2010; online 13 October 2010)

The title complex salt, [Ni(C₃H₈N₂S)₆](NO₃)₂, consists of an [Ni(Dmtu)₆]²⁺ (Dmtu is N,N′-dimethylthiourea) dication and two nitrate counter-anions. The Ni^II atom (site symmetry $[\overline{3}]$ ) is coordinated by the S atoms of six Dmtu ligands within a slightly distorted octahedral environment. The crystal structure is characterized by weak intramolecular N—H⋯S interactions and by intermolecular N—H⋯O hydrogen bonds involving the nitrate anion (site symmetry 3.). These intermolecular interactions lead to the formation of two-dimensional networks lying parallel to the ab plane. The networks are linked via non-classical intermolecular C—H⋯O hydrogen bonds, forming a three-dimensional arrangement.

Related literature

For background to nickel(II) complexes of thiourea and its derivatives, see: Ambujam et al. (2006 ); Basso et al. (1969 ); Bentley & Waters (1974 ); Chiesi et al. (1971 ); Crane & Herod (2004 ); Eaton & Zaw (1975 ); El-Bahy et al. (2003 ); Figgis & Reynolds (1986 ); Monim-ul-Mehboob et al. (2010 ); Sonar et al. (1979 ); Weininger et al. (1969 ); Weininger & Amma (1976 ). For the crystal structures of similar nickel(II) complexes, see: Bentley & Waters (1974); El-Bahy et al. (2003); Monim-ul-Mehboob et al. (2010); Weininger et al. (1969).

Experimental

Crystal data

[Ni(C₃H₈N₂S)₆](NO₃)₂
M_r = 807.77
Trigonal, $[R \overline 3c ]$
a = 13.7166 (10) Å
c = 35.332 (3) Å
V = 5756.9 (8) Å³
Z = 6
Mo Kα radiation
μ = 0.88 mm⁻¹
T = 223 K
0.30 × 0.26 × 0.24 mm

Data collection

Stoe IPDS 2 diffractometer
Absorption correction: multi-scan (MULscanABS; Spek, 2009 ) T_min = 0.963, T_max = 1.000
3491 measured reflections
1199 independent reflections
851 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.029
wR(F²) = 0.056
S = 1.00
1199 reflections
79 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯S1ⁱ	0.86 (2)	2.520 (19)	3.367 (2)	168.6 (17)
N2—H2N⋯O1ⁱⁱ	0.83 (2)	2.14 (2)	2.947 (3)	163.4 (18)
C3—H3B⋯O1ⁱⁱⁱ	0.97	2.41	3.180 (3)	136
Symmetry codes: (i) $[x-y+{\script{1\over 3}}, -y+{\script{2\over 3}}, -z+{\script{1\over 6}}]$ ; (ii) -x+y, -x, z; (iii) y, -x+y, -z.

Data collection: X-AREA (Stoe & Cie, 2009 ); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97, PLATON and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536810040031/wm2412sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810040031/wm2412Isup2.hkl

checkCIF report

Comment top

Several studies have been focused on the synthesis and structural characterization of nickel(II) complexes with thiourea type ligands. These studies showed that nickel(II) can adopt a variety of coordination geometries (octahedral, tetragonal, square-planar and tetrahedral) both in the solid state and in solution, which were prepared by varying the ligands or the anions (Ambujam et al., 2006; Bentley et al., 1974; Chiesi et al., 1971; Eaton & Zaw, 1975; El-Bahy et al., 2003; Figgis & Reynolds, 1986; Monim-ul-Mehboob et al., 2010; Sonar et al., 1979; Weininger et al. 1969, Weininger & Amma, 1976). When the anion is chloride, bromide or iodide, the predominant coordination about the nickel(II) atom in the crystalline solid state is tetragonal with the halide anions in the apical positions, leading to [NiL₄]X₂ complexes (Ambujam et al., 2006; Chiesi et al., 1971; Crane et al., 2004; Figgis & Reynolds, 1986; Weininger & Amma, 1976), although [NiL₆]X₂ complexes are also formed (El-Bahy et al., 2003; Weininger et al., 1969). The formation (in the solid state) of the octahedral species NiL₆²⁺ is ascribed to crystal packing forces and extensive hydrogen bonding (Ambujam et al., 2006; El-Bahy et al., 2003; Monim-ul-Mehboob et al., 2010; Weininger et al., 1969). The coordination of nickel(II) in nitrate and the perchlorate salts is generally homoleptic octahedral in the solid state (Bentley et al., 1974; Monim-ul-Mehboob et al., 2010), but also can give such species as [NiL₂(NO₃)₂] (Basso et al., 1969). We have recently reported on the crystal structure of a thiourea (Tu) complex of nickel(II) nitrate, [Ni(Tu)₆](NO₃)₂ (Monim-ul-Mehboob et al., 2010). Herein, we report on the crystal structure of the title nickel(II) nitrate complex of dimethylthiourea, [Ni(Dmtu)₆](NO₃)₂.

The molecular structure of the title complex is illustrated in Fig. 1. It is ionic and consists of a [Ni(Dmtu)₆]²⁺ cationic unit (site symmetry 3) and two nitrate counter ions (site symmetry 3.). Atom Ni1 assumes a slightly distorted octahedral geometry, due to coordination with six sulfur atoms of the Dmtu ligands. In the cation there are weak N—H···S interactions linking adjacent ligand molecules (Table 1). The values of the bond lengths and bond angles observed in the title complex are comparable to those reported for related complexes (Ambujam et al., 2006; El-Bahy et al., 2003; Monim-ul-Mehboob et al., 2010; Weininger et al., 1969). In the only previously reported nickel(II) complex of N,N'-dimethylthiourea, [Ni(Dmtu)₄]Br₂ (Weininger & Amma, 1976), the nickel(II) atom is 4-coordinate, while in the title complex having the same ligand the nickel(II) atom is 6-coordinate, suggesting that in the presence of nitrate an octahedral coordination is preferred.

In the crystal of the title compound the [Ni(Dmtu)₆]⁺² cations and the NO₃^- ions are connected via N—H···O hydrogen bonds (Table 1) to form two-dimensional networks lying parallel to the ab-plane (Fig. 2). These two-dimensional sheets are linked via C—H···O hydrogen bonds (Table 1), resulting in the formation of a three-dimensional network.

Related literature top

For background to nickel(II) complexes of thiourea and its derivatives, see: Ambujam et al. (2006); Basso et al. (1969); Bentley & Waters (1974); Chiesi et al. (1971); Crane & Herod (2004); Eaton & Zaw (1975); El-Bahy et al. (2003); Figgis & Reynolds (1986); Monim-ul-Mehboob et al. (2010); Sonar et al. (1979); Weininger et al. (1969); Weininger & Amma (1976). For the crystal structures of similar nickel(II) complexes, see: Bentley & Waters (1974); El-Bahy et al. (2003); Monim-ul-Mehboob et al. (2010); Weininger et al. (1969).

Experimental top

The title compound was prepared by adding 2 equivalents of N,N'-dimethylthiourea in 15 ml methanol to 0.29 g (1 mmol) of nickel(II) nitrate hexahydrate in 10 ml methanol. After stirring the mixture for 30 min the solution was filtered. The filtrate on slow evaporation yielded pale-green crystals, suitable for X-ray diffraction analysis.

Structure description top

For background to nickel(II) complexes of thiourea and its derivatives, see: Ambujam et al. (2006); Basso et al. (1969); Bentley & Waters (1974); Chiesi et al. (1971); Crane & Herod (2004); Eaton & Zaw (1975); El-Bahy et al. (2003); Figgis & Reynolds (1986); Monim-ul-Mehboob et al. (2010); Sonar et al. (1979); Weininger et al. (1969); Weininger & Amma (1976). For the crystal structures of similar nickel(II) complexes, see: Bentley & Waters (1974); El-Bahy et al. (2003); Monim-ul-Mehboob et al. (2010); Weininger et al. (1969).

Computing details top

Data collection: X-AREA (Stoe & Cie, 2009); cell refinement: X-AREA (Stoe & Cie, 2009); data reduction: X-RED32 (Stoe & Cie, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. The molecular structure of the title compound with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level [Only one of the nitrate anions is shown; Symmetry codes: a = 1 - y,x-y,z; b = 1 - x + y,1 - x,z; c = 1/3 + y,-1/3 + x,1/6 - z; d = 4/3 - x,2/3 - x + y,1/6 - z; e = 1/3 + x-y,2/3 - y,1/6 - z; f = -y,x-y,z; g = -x + y,-x,z].
	Fig. 2. The crystal packing of the title compound viewed along the c axis (the N—H···O and N—H···S hydrogen bonds are shown as dashed lines - see Table 1 for details; H-atoms not involved in hydrogen bonding have been omitted for clarity).

Hexakis(N,N'-dimethylthiourea-κS)nickel(II) dinitrate top

Crystal data top

[Ni(C₃H₈N₂S)₆](NO₃)₂	D_x = 1.398 Mg m⁻³
M_r = 807.77	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3c	Cell parameters from 2717 reflections
Hall symbol: -R 3 2"c	θ = 2.9–26.1°
a = 13.7166 (10) Å	µ = 0.88 mm⁻¹
c = 35.332 (3) Å	T = 223 K
V = 5756.9 (8) Å³	Block, pale green
Z = 6	0.30 × 0.26 × 0.24 mm
F(000) = 2556

Data collection top

Stoe IPDS 2 diffractometer	1199 independent reflections
Radiation source: fine-focus sealed tube	851 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.028
φ + ω scans	θ_max = 25.6°, θ_min = 2.9°
Absorption correction: multi-scan (MULscanABS; Spek, 2009)	h = −4→14
T_min = 0.963, T_max = 1.000	k = −16→9
3491 measured reflections	l = −42→40

Refinement top

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)] = 0.029	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.056	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.0271P)²] where P = (F_o² + 2F_c²)/3
1199 reflections	(Δ/σ)_max = 0.001
79 parameters	Δρ_max = 0.17 e Å⁻³
2 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

[Ni(C₃H₈N₂S)₆](NO₃)₂	Z = 6
M_r = 807.77	Mo Kα radiation
Trigonal, R3c	µ = 0.88 mm⁻¹
a = 13.7166 (10) Å	T = 223 K
c = 35.332 (3) Å	0.30 × 0.26 × 0.24 mm
V = 5756.9 (8) Å³

Data collection top

Stoe IPDS 2 diffractometer	1199 independent reflections
Absorption correction: multi-scan (MULscanABS; Spek, 2009)	851 reflections with I > 2σ(I)
T_min = 0.963, T_max = 1.000	R_int = 0.028
3491 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.029	2 restraints
wR(F²) = 0.056	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.17 e Å⁻³
1199 reflections	Δρ_min = −0.18 e Å⁻³
79 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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 (Å²) top

	x	y	z	U_iso*/U_eq
Ni1	0.66667	0.33333	0.08333	0.0208 (1)
S1	0.50780 (4)	0.25803 (5)	0.03726 (1)	0.0262 (1)
N1	0.35924 (14)	0.17766 (18)	0.09365 (4)	0.0319 (5)
N2	0.29514 (15)	0.09027 (15)	0.03650 (5)	0.0295 (5)
C1	0.37831 (17)	0.16823 (15)	0.05723 (5)	0.0246 (6)
C2	0.25557 (19)	0.10275 (19)	0.11355 (6)	0.0399 (7)
C3	0.3066 (2)	0.0703 (2)	−0.00341 (6)	0.0409 (8)
O1	0.05182 (15)	0.10490 (12)	0.05290 (4)	0.0449 (5)
N3	0.00000	0.00000	0.05255 (7)	0.0300 (6)
H1N	0.4165 (16)	0.2300 (15)	0.1053 (5)	0.029 (6)*
H2A	0.19490	0.11240	0.10370	0.0600*
H2B	0.26520	0.12040	0.14040	0.0600*
H2C	0.23750	0.02540	0.10990	0.0600*
H2N	0.2303 (14)	0.0569 (17)	0.0455 (5)	0.021 (5)*
H3A	0.34410	0.14160	−0.01680	0.0610*
H3B	0.23250	0.02290	−0.01430	0.0610*
H3C	0.35070	0.03320	−0.00570	0.0610*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Ni1	0.0195 (2)	0.0195 (2)	0.0232 (2)	0.0098 (1)	0.0000	0.0000
S1	0.0203 (2)	0.0277 (3)	0.0272 (2)	0.0095 (3)	−0.0019 (2)	−0.0009 (3)
N1	0.0223 (8)	0.0328 (11)	0.0325 (7)	0.0078 (10)	−0.0009 (6)	−0.0031 (9)
N2	0.0180 (9)	0.0281 (10)	0.0382 (8)	0.0084 (8)	−0.0036 (8)	−0.0040 (8)
C1	0.0218 (10)	0.0222 (11)	0.0336 (9)	0.0138 (8)	−0.0037 (7)	0.0011 (7)
C2	0.0299 (12)	0.0453 (15)	0.0373 (10)	0.0133 (11)	0.0033 (9)	0.0028 (9)
C3	0.0376 (14)	0.0439 (15)	0.0398 (11)	0.0193 (12)	−0.0136 (10)	−0.0131 (10)
O1	0.0306 (10)	0.0206 (7)	0.0794 (10)	0.0097 (9)	0.0077 (10)	0.0079 (7)
N3	0.0261 (9)	0.0261 (9)	0.0379 (13)	0.0131 (5)	0.0000	0.0000

Geometric parameters (Å, º) top

Ni1—S1	2.4929 (6)	N2—C3	1.460 (3)
Ni1—S1ⁱ	2.4929 (7)	N2—C1	1.327 (3)
Ni1—S1ⁱⁱ	2.4929 (5)	N1—H1N	0.86 (2)
Ni1—S1ⁱⁱⁱ	2.4929 (5)	N2—H2N	0.83 (2)
Ni1—S1^iv	2.4929 (6)	C2—H2B	0.9700
Ni1—S1^v	2.4929 (7)	C2—H2C	0.9700
S1—C1	1.727 (2)	C2—H2A	0.9700
O1—N3	1.2462 (14)	C3—H3B	0.9700
N1—C1	1.332 (2)	C3—H3C	0.9700
N1—C2	1.453 (3)	C3—H3A	0.9700

S1—Ni1—S1ⁱ	81.98 (2)	C1—N2—H2N	118.9 (13)
S1—Ni1—S1ⁱⁱ	81.98 (2)	C3—N2—H2N	116.8 (13)
S1—Ni1—S1ⁱⁱⁱ	99.78 (2)	O1—N3—O1^vi	119.99 (14)
S1—Ni1—S1^iv	177.39 (2)	O1^vii—N3—O1^vi	119.99 (14)
S1—Ni1—S1^v	96.33 (2)	O1—N3—O1^vii	119.99 (14)
S1ⁱ—Ni1—S1ⁱⁱ	81.98 (2)	N1—C1—N2	118.7 (2)
S1ⁱ—Ni1—S1ⁱⁱⁱ	96.34 (2)	S1—C1—N2	120.83 (15)
S1ⁱ—Ni1—S1^iv	99.78 (2)	S1—C1—N1	120.48 (16)
S1ⁱ—Ni1—S1^v	177.40 (2)	N1—C2—H2B	109.00
S1ⁱⁱ—Ni1—S1ⁱⁱⁱ	177.40 (3)	H2A—C2—H2C	110.00
S1ⁱⁱ—Ni1—S1^iv	96.33 (2)	N1—C2—H2C	109.00
S1ⁱⁱ—Ni1—S1^v	99.78 (2)	H2A—C2—H2B	110.00
S1ⁱⁱⁱ—Ni1—S1^iv	81.98 (2)	N1—C2—H2A	109.00
S1ⁱⁱⁱ—Ni1—S1^v	81.98 (2)	H2B—C2—H2C	109.00
S1^iv—Ni1—S1^v	81.97 (2)	N2—C3—H3C	109.00
Ni1—S1—C1	113.77 (7)	H3A—C3—H3C	109.00
C1—N1—C2	124.68 (19)	H3B—C3—H3C	110.00
C1—N2—C3	123.7 (2)	H3A—C3—H3B	109.00
C1—N1—H1N	113.7 (13)	N2—C3—H3A	110.00
C2—N1—H1N	121.5 (13)	N2—C3—H3B	109.00

S1ⁱ—Ni1—S1—C1	124.24 (8)	Ni1—S1—C1—N2	−154.41 (17)
S1ⁱⁱ—Ni1—S1—C1	−152.79 (8)	C2—N1—C1—S1	−176.58 (19)
S1ⁱⁱⁱ—Ni1—S1—C1	29.15 (8)	C2—N1—C1—N2	4.9 (4)
S1^v—Ni1—S1—C1	−53.76 (8)	C3—N2—C1—S1	2.9 (3)
Ni1—S1—C1—N1	27.1 (2)	C3—N2—C1—N1	−178.6 (2)

Symmetry codes: (i) −y+1, x−y, z; (ii) −x+y+1, −x+1, z; (iii) y+1/3, x−1/3, −z+1/6; (iv) −x+4/3, −x+y+2/3, −z+1/6; (v) x−y+1/3, −y+2/3, −z+1/6; (vi) −x+y, −x, z; (vii) −y, x−y, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···S1^v	0.86 (2)	2.520 (19)	3.367 (2)	168.6 (17)
N2—H2N···O1^vi	0.83 (2)	2.14 (2)	2.947 (3)	163.4 (18)
C3—H3B···O1^viii	0.97	2.41	3.180 (3)	136

Symmetry codes: (v) x−y+1/3, −y+2/3, −z+1/6; (vi) −x+y, −x, z; (viii) y, −x+y, −z.

Experimental details

Crystal data
Chemical formula	[Ni(C₃H₈N₂S)₆](NO₃)₂
M_r	807.77
Crystal system, space group	Trigonal, R3c
Temperature (K)	223
a, c (Å)	13.7166 (10), 35.332 (3)
V (Å³)	5756.9 (8)
Z	6
Radiation type	Mo Kα
µ (mm⁻¹)	0.88
Crystal size (mm)	0.30 × 0.26 × 0.24

Data collection
Diffractometer	Stoe IPDS 2
Absorption correction	Multi-scan (MULscanABS; Spek, 2009)
T_min, T_max	0.963, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	3491, 1199, 851
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.609

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.029, 0.056, 1.00
No. of reflections	1199
No. of parameters	79
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.18

Computer programs: X-AREA (Stoe & Cie, 2009), X-RED32 (Stoe & Cie, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···S1ⁱ	0.86 (2)	2.520 (19)	3.367 (2)	168.6 (17)
N2—H2N···O1ⁱⁱ	0.83 (2)	2.14 (2)	2.947 (3)	163.4 (18)
C3—H3B···O1ⁱⁱⁱ	0.97	2.41	3.180 (3)	136

Symmetry codes: (i) x−y+1/3, −y+2/3, −z+1/6; (ii) −x+y, −x, z; (iii) y, −x+y, −z.

Acknowledgements

We thank the staff of the X-ray Application Lab, CSEM, Neuchâtel, for access to the X-ray diffraction equipement.

References

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