[μ-N1,N2-Bis(pyridin-2-yl)hydrazine-1,2-dicarbothio­amidato]bis­[chlorido­copper(II)]

Liu, Y.; Zhang, B.; Deng, K.

doi:10.1107/S1600536812048659

metal-organic compounds

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Volume 69| Part 1| January 2013| Page m45

https://doi.org/10.1107/S1600536812048659

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[μ-N¹,N²-Bis(pyridin-2-yl)hydrazine-1,2-dicarbothioamidato]bis[chloridocopper(II)]

Yang Liu,^a Bingguang Zhang ^a ^* and Kejian Deng ^a

^aCollege of Chemistry and Material Science, South-Central University for Nationalities, Wuhan, Hubei 430074, People's Republic of China
^*Correspondence e-mail: zhangbg68@yahoo.com

(Received 16 March 2012; accepted 27 November 2012; online 12 December 2012)

The binuclear title compound, [Cu₂(C₁₂H₁₀N₆S₂)Cl₂], possesses twofold rotational symmetry. The Cu^II atom occupies a four-coordinate pseudo-tetrahedral environment bound to one S atom, one imine N atom and one pyridine N atom from the N¹,N²-bis(pyridin-2-yl)hydrazine-1,2-dicarbothioamidate ligand, and one Cl⁻ anion. The metal atoms are connected via the bis-tridentate ligand into a binuclear structure. The molecule is bow-shaped with the pyridine rings inclined to one another by 51.56 (14)°. In the crystal, N—H⋯Cl hydrogen bonds lead to the formation of ribbons propagating along [001]. These ribbons are connected via C—H⋯Cl, C—H⋯S and π–π interactions [centroid–centroid distance = 3.6146 (19) Å], leading to the formation of a three-dimensional structure.

Related literature

For the biological activity of thiosemicarbazides and their metal complexes, see: West et al. (1993 ). For related structures, see: Wang et al. (2011 ); Yamin & Yusof (2003 ); Akinchan et al. (2002 ). For the synthesis of the ligand, see: Szecsenyi et al. (2006 ).

Experimental

Crystal data

[Cu₂(C₁₂H₁₀N₆S₂)Cl₂]
M_r = 500.36
Monoclinic, C 2/c
a = 15.825 (3) Å
b = 7.6190 (13) Å
c = 15.082 (4) Å
β = 118.179 (2)°
V = 1602.9 (6) Å³
Z = 4
Mo Kα radiation
μ = 3.26 mm⁻¹
T = 293 K
0.32 × 0.28 × 0.27 mm

Data collection

Bruker SMART APEX CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2003 ) T_min = 0.422, T_max = 0.474
4270 measured reflections
1561 independent reflections
1445 reflections with I > 2σ(I)
R_int = 0.018

Refinement

R[F² > 2σ(F²)] = 0.024
wR(F²) = 0.068
S = 1.07
1561 reflections
110 parameters
H-atom parameters constrained
Δρ_max = 0.73 e Å⁻³
Δρ_min = −0.34 e Å⁻³

Table 1
Selected bond lengths (Å)

Cu1—Cl1	2.2619 (10)
Cu1—S2	2.2295 (9)
Cu1—N1	1.986 (2)
Cu1—N3ⁱ	1.961 (3)
Symmetry code: (i) $[-x, y, -z+{\script{1\over 2}}]$ .

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2A⋯Cl1ⁱⁱ	0.86	2.70	3.507 (2)	156
C2—H2⋯Cl1ⁱⁱⁱ	0.93	2.77	3.482 (3)	134
C5—H5⋯S2^iv	0.93	2.82	3.425 (3)	124
Symmetry codes: (ii) $[x, -y+1, z+{\script{1\over 2}}]$ ; (iii) $[x-{\script{1\over 2}}, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 2003); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812048659/su2393sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812048659/su2393Isup2.hkl

checkCIF report

Comment top

Thiosemicarbazide and their metal complexes have attracked considerable interest due to their biological activities, such as antiviral, antibacterial, antimalarial, antifungal, and antitumoral activities (West et al., 1993). Thiosemicarbazide are versatile ligands that can coordinate as neutral ligands or in the deprotonated form. They can also be used as flexible spacers with potential multiple binding sites to construct coordination polymers with multiple dimensions and various topologies. In the present paper, the synthesis and crystal structure of the title thiosemicarbazide binuclear copper(II) compound is reported.

The title compound possesses twofold rotational symmetry (Fig.1). Each Cu^II center occupies a four-coordinated pseudotetrahedral environment bound to one sulfur atom, one imine nitrogen atom, and one pyridine nitrogen atom from one N,N'-di(pyridin-2-yl)hydrazine-1,2-bis(carbothioamide) ligand, and one chlorine anion. The metal centres are connected via the hexadentate ligand into a binuclear structure. The molecule is bow-shaped. The thiosemicarbazide moiety (S2/N2(N3/N6) is twisted by 20.14 (13)° from the pyridine ring to which it is attached. The two thiosemicarbazide moieties, (S2/N2/N3/N6) and (S2A/N2A/N3A/N6A), are inclined to one another by 23.36 (13) °, while the pyrdine rings make a dihedral angle of 51.56 (14)°.

The Cu—S distance is 2.2295 (9) Å, and the Cu—N distances vary between 1.961 (3)–1.986 (2) Å. The C—S bond distances of 1.711 (3) Å are within the normal range for a C—S single bond, indicating that the thiosemicarbazide moieties adopt the thiol tautomeric form, acting as a doubly charged negative ligand. The C6—N distances of 1.311 (3)–1.366 (3) Å and the N3—N3A distance of 1.399 (3) Å are intermediate between formal single and double bonds, pointing to extensive electron delocalization over the entire ligand skeleton. This agrees well with the same distances observed in related compounds (Wang et al., 2011; Yamin & Yusof, 2003; Akinchan et al., 2002).

In the crystal, there are N-H···Cl hydrogen bonds, leading to the formation of ribbons propagating along [001], and C-H···Cl and C-H···S interactions (Table 1). The latter link the ribbons and together with π–π interactions lead to the formation of a three-dimensional structure [Cg1···Cg1ⁱ 3.6146 (19) Å; perpendicular separation 3.5312 (11) Å; slippage 0.772 Å; Cg1 is the centroid of pyrdine ring N1/C1-C5; symmetry code: (i) -x, -y+2, -z].

Related literature top

For the biological activity of thiosemicarbazides and their metal complexes, see: West et al. (1993). For related structures, see: Wang et al. (2011); Yamin & Yusof (2003); Akinchan et al. (2002). For the synthesis of the ligand, see: Szecsenyi et al. (2006).

Experimental top

The ligand (L), N,N'-di(pyridin-2-yl)hydrazine-1,2-bis(carbothioamide,) was prepared by the literature method (Szecsenyi et al., 2006). L (0.05 mmol) was solved in DMF (5 ml) in a test tube, then an 8 ml solvent mixture of CH₃OH and DMF (v/v = 1:1) was added as a buffer layer. A solution of CuCl₂(0.10 mmol) in CH₃OH (3 ml) was then carefully layered on top. The system was sealed and kept for a week, after which black block-like single crystals, suitable for X-ray analysis, were obtained. Anal. Calcd for C₁₂H₁₀Cl₂Cu₂N₆S₂: C 28.80, H 2.01, N16.80. Found: C 29.23; H, 2.40; N, 16.44.

Structure description top

For the biological activity of thiosemicarbazides and their metal complexes, see: West et al. (1993). For related structures, see: Wang et al. (2011); Yamin & Yusof (2003); Akinchan et al. (2002). For the synthesis of the ligand, see: Szecsenyi et al. (2006).

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of title compound, with the atom numbering. The displacement ellipsoids are drawn at the 50% probability level [symmetry code: (a) - x, y, - z + 1/2].

[µ-N¹,N²-Bis(pyridin-2-yl)hydrazine-1,2- dicarbothioamidato]bis[chloridocopper(II)] top

Crystal data top

[Cu₂(C₁₂H₁₀N₆S₂)Cl₂]	F(000) = 992
M_r = 500.36	D_x = 2.073 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 253 reflections
a = 15.825 (3) Å	θ = 2.9–29.5°
b = 7.6190 (13) Å	µ = 3.26 mm⁻¹
c = 15.082 (4) Å	T = 293 K
β = 118.179 (2)°	Block, black
V = 1602.9 (6) Å³	0.32 × 0.28 × 0.27 mm
Z = 4

Data collection top

Bruker SMART APEX CCD diffractometer	1561 independent reflections
Radiation source: fine-focus sealed tube	1445 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.018
φ and ω scans	θ_max = 26.0°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2003)	h = −19→18
T_min = 0.422, T_max = 0.474	k = −9→7
4270 measured reflections	l = −18→17

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.024	H-atom parameters constrained
wR(F²) = 0.068	w = 1/[σ²(F_o²) + (0.0374P)² + 2.3083P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
1561 reflections	Δρ_max = 0.73 e Å⁻³
110 parameters	Δρ_min = −0.34 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0018 (3)

Crystal data top

[Cu₂(C₁₂H₁₀N₆S₂)Cl₂]	V = 1602.9 (6) Å³
M_r = 500.36	Z = 4
Monoclinic, C2/c	Mo Kα radiation
a = 15.825 (3) Å	µ = 3.26 mm⁻¹
b = 7.6190 (13) Å	T = 293 K
c = 15.082 (4) Å	0.32 × 0.28 × 0.27 mm
β = 118.179 (2)°

Data collection top

Bruker SMART APEX CCD diffractometer	1561 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2003)	1445 reflections with I > 2σ(I)
T_min = 0.422, T_max = 0.474	R_int = 0.018
4270 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.024	0 restraints
wR(F²) = 0.068	H-atom parameters constrained
S = 1.07	Δρ_max = 0.73 e Å⁻³
1561 reflections	Δρ_min = −0.34 e Å⁻³
110 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 esds 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
Cu1	0.12780 (2)	0.63445 (4)	0.20890 (2)	0.0266 (1)
Cl1	0.25399 (4)	0.50248 (9)	0.20491 (5)	0.0355 (2)
S2	0.18501 (4)	0.59737 (10)	0.37400 (5)	0.0336 (2)
N1	0.07304 (14)	0.7259 (3)	0.06931 (14)	0.0267 (6)
N2	0.08612 (15)	0.6577 (3)	0.46876 (15)	0.0297 (6)
N3	−0.00303 (14)	0.6631 (3)	0.29480 (15)	0.0258 (6)
C1	−0.02056 (17)	0.7259 (3)	0.00390 (18)	0.0265 (7)
C2	−0.05668 (19)	0.7912 (4)	−0.09283 (19)	0.0356 (8)
C3	0.0058 (2)	0.8611 (4)	−0.1223 (2)	0.0452 (10)
C4	0.1031 (2)	0.8622 (4)	−0.0559 (2)	0.0434 (10)
C5	0.13323 (19)	0.7951 (4)	0.03822 (19)	0.0340 (8)
C6	0.07986 (17)	0.6433 (3)	0.37555 (18)	0.0248 (7)
H2	−0.12210	0.78770	−0.13690	0.0430*
H2A	0.13840	0.61870	0.51760	0.0360*
H3	−0.01690	0.90740	−0.18660	0.0540*
H4	0.14670	0.90750	−0.07490	0.0520*
H5	0.19850	0.79710	0.08320	0.0410*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0178 (2)	0.0406 (2)	0.0238 (2)	0.0017 (1)	0.0118 (1)	0.0002 (1)
Cl1	0.0250 (3)	0.0472 (4)	0.0381 (3)	0.0039 (3)	0.0181 (3)	−0.0055 (3)
S2	0.0188 (3)	0.0567 (4)	0.0270 (3)	0.0091 (3)	0.0123 (3)	0.0067 (3)
N1	0.0221 (10)	0.0354 (12)	0.0249 (10)	−0.0031 (8)	0.0131 (8)	−0.0023 (9)
N2	0.0190 (10)	0.0477 (13)	0.0217 (10)	0.0072 (9)	0.0090 (9)	0.0026 (9)
N3	0.0191 (10)	0.0392 (12)	0.0213 (9)	−0.0001 (8)	0.0113 (8)	0.0005 (8)
C1	0.0251 (12)	0.0323 (13)	0.0260 (11)	−0.0019 (10)	0.0152 (10)	−0.0031 (10)
C2	0.0294 (13)	0.0508 (17)	0.0245 (12)	−0.0022 (12)	0.0109 (11)	0.0020 (11)
C3	0.0462 (18)	0.064 (2)	0.0302 (14)	−0.0015 (14)	0.0221 (14)	0.0078 (13)
C4	0.0428 (17)	0.0564 (19)	0.0422 (16)	−0.0074 (13)	0.0294 (15)	0.0031 (13)
C5	0.0268 (13)	0.0445 (15)	0.0354 (13)	−0.0062 (11)	0.0186 (12)	−0.0029 (12)
C6	0.0204 (12)	0.0304 (13)	0.0252 (11)	0.0001 (9)	0.0121 (10)	0.0007 (9)

Geometric parameters (Å, º) top

Cu1—Cl1	2.2619 (10)	N3—N3ⁱ	1.399 (3)
Cu1—S2	2.2295 (9)	N2—H2A	0.8600
Cu1—N1	1.986 (2)	C1—C2	1.384 (4)
Cu1—N3ⁱ	1.961 (3)	C2—C3	1.369 (5)
S2—C6	1.711 (3)	C3—C4	1.385 (4)
N1—C1	1.337 (4)	C4—C5	1.366 (4)
N1—C5	1.352 (4)	C2—H2	0.9300
N2—C6	1.366 (3)	C3—H3	0.9300
N2—C1ⁱ	1.386 (4)	C4—H4	0.9300
N3—C6	1.311 (3)	C5—H5	0.9300

Cl1—Cu1—S2	94.32 (3)	N1—C1—C2	122.7 (3)
Cl1—Cu1—N1	94.39 (7)	N1—C1—N2ⁱ	120.3 (2)
Cl1—Cu1—N3ⁱ	159.80 (7)	C1—C2—C3	118.7 (3)
S2—Cu1—N1	166.41 (7)	C2—C3—C4	119.6 (3)
S2—Cu1—N3ⁱ	85.31 (6)	C3—C4—C5	118.2 (3)
N1—Cu1—N3ⁱ	90.08 (9)	N1—C5—C4	123.3 (3)
Cu1—S2—C6	96.01 (9)	N2—C6—N3	120.1 (3)
Cu1—N1—C1	123.98 (19)	S2—C6—N2	115.6 (2)
Cu1—N1—C5	118.58 (18)	S2—C6—N3	124.3 (2)
C1—N1—C5	117.4 (2)	C1—C2—H2	121.00
C1ⁱ—N2—C6	129.5 (2)	C3—C2—H2	121.00
Cu1ⁱ—N3—C6	124.48 (19)	C2—C3—H3	120.00
N3ⁱ—N3—C6	113.7 (2)	C4—C3—H3	120.00
Cu1ⁱ—N3—N3ⁱ	119.99 (16)	C3—C4—H4	121.00
C6—N2—H2A	115.00	C5—C4—H4	121.00
C1ⁱ—N2—H2A	115.00	N1—C5—H5	118.00
N2ⁱ—C1—C2	117.0 (3)	C4—C5—H5	118.00

Cl1—Cu1—S2—C6	−165.43 (8)	C5—N1—C1—N2ⁱ	−179.7 (2)
N3ⁱ—Cu1—S2—C6	−5.68 (11)	Cu1—N1—C5—C4	−179.7 (2)
Cl1—Cu1—N1—C1	138.8 (2)	C1ⁱ—N2—C6—S2	166.0 (2)
Cl1—Cu1—N1—C5	−42.3 (2)	C6ⁱ—N2ⁱ—C1—N1	26.4 (4)
N3ⁱ—Cu1—N1—C1	−21.5 (2)	C6ⁱ—N2ⁱ—C1—C2	−154.0 (3)
N3ⁱ—Cu1—N1—C5	157.5 (2)	C1ⁱ—N2—C6—N3	−14.5 (4)
Cl1—Cu1—N3ⁱ—N3	94.0 (2)	N3ⁱ—N3—C6—N2	173.7 (2)
Cl1—Cu1—N3ⁱ—C6ⁱ	−69.8 (3)	Cu1ⁱ—N3—C6—S2	157.76 (14)
S2—Cu1—N3ⁱ—N3	4.18 (18)	Cu1ⁱ—N3—C6—N2	−21.7 (3)
S2—Cu1—N3ⁱ—C6ⁱ	−159.6 (2)	C6—N3—N3ⁱ—Cu1	0.2 (3)
N1—Cu1—N3ⁱ—N3	−163.03 (19)	C6—N3—N3ⁱ—C6ⁱ	165.6 (2)
N1—Cu1—N3ⁱ—C6ⁱ	33.2 (2)	Cu1ⁱ—N3—N3ⁱ—Cu1	−165.23 (11)
Cu1—S2—C6—N2	−171.77 (17)	N3ⁱ—N3—C6—S2	−6.9 (3)
Cu1—S2—C6—N3	8.8 (2)	N1—C1—C2—C3	−1.0 (4)
C1—N1—C5—C4	−0.7 (4)	N2ⁱ—C1—C2—C3	179.4 (3)
Cu1—N1—C1—C2	179.7 (2)	C1—C2—C3—C4	1.1 (4)
C5—N1—C1—C2	0.8 (4)	C2—C3—C4—C5	−1.0 (5)
Cu1—N1—C1—N2ⁱ	−0.7 (3)	C3—C4—C5—N1	0.8 (5)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···Cl1ⁱⁱ	0.86	2.70	3.507 (2)	156
C2—H2···Cl1ⁱⁱⁱ	0.93	2.77	3.482 (3)	134
C5—H5···S2^iv	0.93	2.82	3.425 (3)	124

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

Experimental details

Crystal data
Chemical formula	[Cu₂(C₁₂H₁₀N₆S₂)Cl₂]
M_r	500.36
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	15.825 (3), 7.6190 (13), 15.082 (4)
β (°)	118.179 (2)
V (Å³)	1602.9 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	3.26
Crystal size (mm)	0.32 × 0.28 × 0.27

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2003)
T_min, T_max	0.422, 0.474
No. of measured, independent and observed [I > 2σ(I)] reflections	4270, 1561, 1445
R_int	0.018
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.024, 0.068, 1.07
No. of reflections	1561
No. of parameters	110
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.73, −0.34

Computer programs: SMART (Bruker, 2003), SAINT-Plus (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top

Cu1—Cl1	2.2619 (10)	Cu1—N1	1.986 (2)
Cu1—S2	2.2295 (9)	Cu1—N3ⁱ	1.961 (3)

Symmetry code: (i) −x, y, −z+1/2.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···Cl1ⁱⁱ	0.86	2.70	3.507 (2)	156
C2—H2···Cl1ⁱⁱⁱ	0.93	2.77	3.482 (3)	134
C5—H5···S2^iv	0.93	2.82	3.425 (3)	124

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

Acknowledgements

This work was sponsored by the National Natural Science Foundation of China (No. 20977115).

References

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