Crystal structure of bis­(azido-κN)bis[2,5-bis(pyridin-2-yl)-1,3,4-thia­diazole-κ2N2,N3]cobalt(II)

Laachir, A.; Bentiss, F.; Guesmi, S.; Saadi, M.; El Ammari, L.

doi:10.1107/S2056989015006544

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ISSN: 2056-9890

Volume 71| Part 5| May 2015| Pages 452-454

https://doi.org/10.1107/S2056989015006544

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Crystal structure of bis(azido-κN)bis[2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole-κ²N²,N³]cobalt(II)

Abdelhakim Laachir,^a Fouad Bentiss,^b Salaheddine Guesmi,^a ^* Mohamed Saadi ^c and Lahcen El Ammari ^c

^aLaboratoire de Chimie de Coordination et d'Analytique (LCCA), Faculté des Sciences, Université Chouaib Doukkali, BP 20, M-24000 El Jadida, Morocco, ^bLaboratoire de Catalyse et de Corrosion de Matériaux (LCCM), Faculté des Sciences, Université Chouaib Doukkali, BP 20, M-24000 El Jadida, Morocco, and ^cLaboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V, Avenue Ibn Battouta, BP 1014, Rabat, Morocco
^*Correspondence e-mail: salaheddine_guesmi@yahoo.fr

Edited by C. Rizzoli, Universita degli Studi di Parma, Italy (Received 19 March 2015; accepted 31 March 2015; online 9 April 2015)

In the mononuclear title complex, [Co(N₃)₂(C₁₂H₈N₄S)₂], the cobalt(II) atom is located on an inversion centre and displays an axially weakly compressed octahedral coordination geometry. The equatorial positions are occupied by the N atoms of two 2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole ligands, whereas the axial positions are occupied by N atoms of the azide anions. The thiadiazole and pyridine rings linked to the metal are almost coplanar, with a maximum deviation from the mean plane of 0.0273 (16) Å. The cohesion of the crystal is ensured by weak C—H⋯N hydrogen bonds and by π–π interactions between pyridine rings [intercentroid distance = 3.6356 (11) Å], forming a layered arrangement parallel to (001). The structure of the title compound is isotypic with that of the analogous nickel(II) complex [Laachir et al. (2013 ). Acta Cryst. E69, m351–m352].

Keywords: crystal structure; transition metal; 2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole ligand; azide compounds; hydrogen bonding; π–π interactions.

CCDC reference: 1057234

1. Chemical context

In recent years, the use of the ligand 2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole has been studied for the synthesis of numerous complexes with transition-metal salts. An interesting feature of the metal–ligand chemistry of these compounds is that the resulting complexes can be mononuclear (Bentiss et al., 2011a ; 2012 ; Kaase et al., 2014 ) or binuclear (Bentiss et al., 2004 ; Laachir et al., 2013). Another preparation method involves the use of the organic ligand and pseudohalide ions, especially the azide ion which is known to exhibit different coordination modes (Nath & Baruah, 2012 ; Ray et al., 2011 ).

2. Structural commentary

The structure of the title compound (Fig. 1) is isotypic with its nickel(II) analogue (Laachir et al., 2015 ) and similar to that of the homologous compound, [Co(C₁₂H₈N₄S)₂(H₂O)₂]·2BF₄, in which the water molecules are substituted by azide ions which at the same time neutralize the positive charge of Co²⁺ (Bentiss et al., 2011b ). The main difference between the two structures lies in the values of the dihedral angle between the two pyridine rings: this is 18.72 (6)° in the hydrated molecule, whereas it is 3.03 (2)° in the title molecule, (I). The dihedral angles formed by the thiadiazole ring and the pyridine rings N1/C1–C4 and N2/C8–C11 in (I) are 2.87 (9) and 1.1 (2)°, respectively. The cobalt cation, which is located on an inversion centre, shows an axially weakly compressed octahedral coordination geometry with the equatorial plane provided by four nitrogen atoms belonging to the pyridine and thiadiazole rings of two organic ligands [Co1—N3 = 2.1301 (14) and Co1—N4 = 2.1535 (14) Å] and the axial positions occupied by two nitrogen atoms from azide anions [Co1—N5 = 2.1132 (17) Å].

Figure 1
The molecular structure of the title compound with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as spheres of arbitrary radius. [Symmetry code: (i) −x, −y, −z.]

3. Supramolecular features

In the crystal, the molecules are linked by π–π interactions between pyridine rings [intercentroid distance = 3.6356 (11) Å] and by weak C—H⋯N hydrogen bonds (Table 1), forming a layered arrangement parallel to (001) (Fig. 2). The layers are connected by further C—H⋯N hydrogen bonds into a three-dimensional network.

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯N6ⁱ	0.93	2.59	3.432 (3)	151
C11—H11⋯N7ⁱⁱ	0.93	2.60	3.528 (3)	173
C10—H10⋯N1ⁱⁱⁱ	0.93	2.63	3.438 (2)	146
Symmetry codes: (i) x+1, y+1, z; (ii) x-1, y, z; (iii) $[-x, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Figure 2
Partial crystal packing of the title compound, showing intermolecular π–π interactions between pyridine rings (dashed green lines) and intermolecular C—H⋯N hydrogen bonds (dashed blue lines).

4. Synthesis and crystallization

The ligand 2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole (noted L) was synthesized as described previously by Lebrini et al. (2005 ). The complex [CoL₂(N₃)₂] was synthesized in bulk quantity by dropwise addition with constant stirring at room temperature of an aqueous solution of NaN₃ (0.4 mmol, 26 mg) to an ethanol/water solution (1:1 v/v) of L (0.1 mmol, 24 mg) and CoCl₂·6H₂O (0.1 mmol, 24 mg). The red-coloured solid precipitated was filtered and washed with cold ethanol. Single crystals of the title compound suitable for X-ray data collection were obtained by slow interdiffusion of a solution of CoCl₂·6H₂O and L in acetonitrile into NaN₃ dissolved in water. Red block-shaped single crystals appeared after one month. The crystals were washed with water and dried under vacuum (yield 60%). Analysis calculated for C₂₄H₁₆N₁₄CoS₂: C, 46.23; H, 2.59; N, 31.45 S, 10.28. Found: C, 46.42; H, 2.63; N, 31.35; S, 10.51.

CAUTION! Azide compounds are potentially explosive. Only a small amount of material should be prepared and handled with care.

5. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were located in a difference Fourier map and treated as riding, with C—H = 0.93 Å, and with U_iso(H) = 1.2 U_eq(C). Two outliers (002 and $[\overline{2}]$ 24) were omitted in the last cycles of refinement.

Table 2
Experimental details

Crystal data
Chemical formula	[Co(N₃)₂(C₁₂H₈N₄S)₂]
M_r	623.56
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	296
a, b, c (Å)	7.8004 (3), 8.2439 (3), 20.3222 (8)
β (°)	92.910 (2)
V (Å³)	1305.15 (9)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	0.86
Crystal size (mm)	0.39 × 0.31 × 0.18

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2009 )
T_min, T_max	0.640, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	27415, 3667, 2884
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.694

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.088, 1.03
No. of reflections	3667
No. of parameters	187
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.70, −0.26
Computer programs: APEX2 and SAINT (Bruker, 2009), SHELXS97 and SHELXL97 (Sheldrick, 2008 ), ORTEP-3 for Windows and WinGX (Farrugia, 2012 ).

Supporting information

CCDC reference: 1057234

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015006544/rz5153sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015006544/rz5153Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: WinGX (Farrugia, 2012).

Bis(azido-κN)bis[2,5-bis(pyridin-2-yl)-1,3,4-thiadiazole-κ²N²,N³]cobalt(II) top

Crystal data top

[Co(N₃)₂(C₁₂H₈N₄S)₂]	F(000) = 634
M_r = 623.56	D_x = 1.587 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3667 reflections
a = 7.8004 (3) Å	θ = 2.6–29.6°
b = 8.2439 (3) Å	µ = 0.86 mm⁻¹
c = 20.3222 (8) Å	T = 296 K
β = 92.910 (2)°	Block, red
V = 1305.15 (9) Å³	0.39 × 0.31 × 0.18 mm
Z = 2

Data collection top

Bruker APEXII CCD diffractometer	3667 independent reflections
Radiation source: fine-focus sealed tube	2884 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.043
φ and ω scans	θ_max = 29.6°, θ_min = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −8→10
T_min = 0.640, T_max = 0.747	k = −11→11
27415 measured reflections	l = −28→28

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.088	H-atom parameters constrained
S = 1.03	w = 1/[σ²(F_o²) + (0.0381P)² + 0.5683P] where P = (F_o² + 2F_c²)/3
3667 reflections	(Δ/σ)_max < 0.001
187 parameters	Δρ_max = 0.70 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.7907 (3)	0.4986 (3)	0.07266 (12)	0.0486 (5)
H1	0.8731	0.5035	0.0412	0.058*
C2	0.8166 (3)	0.5770 (3)	0.13200 (13)	0.0540 (6)
H2	0.9169	0.6353	0.1416	0.065*
C3	0.6910 (3)	0.5672 (3)	0.17662 (13)	0.0568 (6)
H3	0.7097	0.6203	0.2167	0.068*
N1	0.5445 (2)	0.4873 (2)	0.16646 (9)	0.0448 (4)
C5	0.5212 (2)	0.4114 (2)	0.10851 (9)	0.0316 (4)
C6	0.3585 (2)	0.3225 (2)	0.10077 (8)	0.0298 (4)
C7	0.0891 (2)	0.1991 (2)	0.11550 (8)	0.0285 (3)
C8	−0.0761 (2)	0.1314 (2)	0.13257 (8)	0.0276 (3)
C9	−0.1510 (2)	0.1627 (2)	0.19143 (8)	0.0338 (4)
H9	−0.0963	0.2283	0.2233	0.041*
C10	−0.3087 (2)	0.0943 (2)	0.20186 (9)	0.0369 (4)
H10	−0.3623	0.1133	0.2410	0.044*
C11	−0.3856 (2)	−0.0022 (2)	0.15379 (10)	0.0382 (4)
H11	−0.4920	−0.0493	0.1599	0.046*
C12	−0.3022 (2)	−0.0285 (2)	0.09601 (9)	0.0348 (4)
H12	−0.3547	−0.0941	0.0637	0.042*
C4	0.6406 (2)	0.4123 (2)	0.06039 (10)	0.0383 (4)
H4	0.6204	0.3565	0.0210	0.046*
N2	0.30958 (18)	0.23430 (19)	0.05046 (7)	0.0314 (3)
N3	0.15296 (18)	0.16405 (19)	0.05884 (7)	0.0307 (3)
N4	−0.14945 (18)	0.03680 (18)	0.08497 (7)	0.0285 (3)
N5	0.1294 (2)	−0.1959 (2)	0.04761 (8)	0.0425 (4)
N6	0.1687 (2)	−0.1872 (2)	0.10472 (8)	0.0394 (4)
N7	0.2046 (3)	−0.1805 (3)	0.16093 (9)	0.0650 (6)
S1	0.21579 (6)	0.32700 (6)	0.16328 (2)	0.03604 (12)
Co1	0.0000	0.0000	0.0000	0.02677 (10)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0316 (10)	0.0552 (13)	0.0600 (14)	−0.0009 (10)	0.0134 (9)	0.0183 (11)
C2	0.0366 (11)	0.0422 (12)	0.0829 (17)	−0.0157 (10)	0.0016 (11)	0.0003 (12)
C3	0.0475 (13)	0.0543 (14)	0.0687 (15)	−0.0162 (11)	0.0041 (11)	−0.0261 (12)
N1	0.0358 (9)	0.0484 (10)	0.0508 (10)	−0.0103 (8)	0.0086 (8)	−0.0184 (8)
C5	0.0270 (8)	0.0304 (9)	0.0371 (9)	−0.0022 (7)	0.0009 (7)	0.0008 (7)
C6	0.0269 (8)	0.0349 (9)	0.0278 (8)	−0.0020 (7)	0.0028 (7)	0.0002 (7)
C7	0.0292 (8)	0.0349 (9)	0.0213 (7)	−0.0025 (7)	0.0004 (6)	−0.0024 (6)
C8	0.0277 (8)	0.0330 (9)	0.0223 (7)	−0.0009 (7)	0.0028 (6)	0.0013 (6)
C9	0.0368 (9)	0.0432 (10)	0.0216 (8)	−0.0008 (8)	0.0040 (7)	−0.0026 (7)
C10	0.0371 (9)	0.0468 (11)	0.0280 (9)	0.0032 (9)	0.0118 (7)	0.0033 (8)
C11	0.0308 (9)	0.0445 (11)	0.0403 (10)	−0.0032 (8)	0.0112 (8)	0.0055 (8)
C12	0.0310 (9)	0.0393 (10)	0.0342 (9)	−0.0060 (8)	0.0042 (7)	−0.0026 (7)
C4	0.0353 (9)	0.0443 (11)	0.0355 (10)	0.0012 (8)	0.0029 (8)	0.0038 (8)
N2	0.0284 (7)	0.0407 (8)	0.0252 (7)	−0.0078 (6)	0.0032 (6)	−0.0028 (6)
N3	0.0281 (7)	0.0411 (8)	0.0229 (7)	−0.0064 (6)	0.0028 (6)	−0.0027 (6)
N4	0.0283 (7)	0.0340 (7)	0.0235 (7)	−0.0032 (6)	0.0034 (6)	−0.0012 (6)
N5	0.0489 (10)	0.0472 (10)	0.0316 (8)	0.0043 (8)	0.0037 (7)	0.0004 (7)
N6	0.0301 (8)	0.0476 (10)	0.0404 (9)	−0.0064 (7)	0.0010 (7)	0.0125 (7)
N7	0.0610 (13)	0.0935 (17)	0.0391 (10)	−0.0169 (12)	−0.0125 (9)	0.0198 (10)
S1	0.0322 (2)	0.0481 (3)	0.0282 (2)	−0.0092 (2)	0.00487 (17)	−0.01202 (19)
Co1	0.02599 (16)	0.03633 (19)	0.01818 (15)	−0.00561 (14)	0.00290 (11)	−0.00329 (13)

Geometric parameters (Å, º) top

C1—C2	1.374 (3)	C9—H9	0.9300
C1—C4	1.382 (3)	C10—C11	1.374 (3)
C1—H1	0.9300	C10—H10	0.9300
C2—C3	1.371 (3)	C11—C12	1.388 (3)
C2—H2	0.9300	C11—H11	0.9300
C3—N1	1.326 (3)	C12—N4	1.337 (2)
C3—H3	0.9300	C12—H12	0.9300
N1—C5	1.338 (2)	C4—H4	0.9300
C5—C4	1.384 (3)	N2—N3	1.3704 (19)
C5—C6	1.467 (2)	N3—Co1	2.1301 (14)
C6—N2	1.297 (2)	N4—Co1	2.1535 (14)
C6—S1	1.7317 (16)	N5—N6	1.187 (2)
C7—N3	1.310 (2)	N5—Co1	2.1132 (17)
C7—C8	1.462 (2)	N6—N7	1.164 (2)
C7—S1	1.7128 (17)	Co1—N5ⁱ	2.1132 (17)
C8—N4	1.347 (2)	Co1—N3ⁱ	2.1301 (14)
C8—C9	1.382 (2)	Co1—N4ⁱ	2.1535 (14)
C9—C10	1.380 (3)

C2—C1—C4	119.10 (19)	N4—C12—C11	122.64 (17)
C2—C1—H1	120.5	N4—C12—H12	118.7
C4—C1—H1	120.5	C11—C12—H12	118.7
C3—C2—C1	118.31 (19)	C1—C4—C5	118.00 (19)
C3—C2—H2	120.8	C1—C4—H4	121.0
C1—C2—H2	120.8	C5—C4—H4	121.0
N1—C3—C2	124.4 (2)	C6—N2—N3	111.59 (13)
N1—C3—H3	117.8	C7—N3—N2	113.40 (14)
C2—C3—H3	117.8	C7—N3—Co1	113.97 (11)
C3—N1—C5	116.54 (18)	N2—N3—Co1	132.53 (10)
N1—C5—C4	123.60 (17)	C12—N4—C8	117.54 (15)
N1—C5—C6	113.95 (15)	C12—N4—Co1	126.96 (12)
C4—C5—C6	122.44 (17)	C8—N4—Co1	115.44 (11)
N2—C6—C5	125.69 (15)	N6—N5—Co1	119.66 (14)
N2—C6—S1	114.57 (12)	N7—N6—N5	178.7 (2)
C5—C6—S1	119.72 (13)	C7—S1—C6	86.85 (8)
N3—C7—C8	120.22 (15)	N5—Co1—N5ⁱ	180.0
N3—C7—S1	113.57 (13)	N5—Co1—N3ⁱ	90.73 (6)
C8—C7—S1	126.20 (12)	N5ⁱ—Co1—N3ⁱ	89.27 (6)
N4—C8—C9	123.13 (16)	N5—Co1—N3	89.27 (6)
N4—C8—C7	113.46 (14)	N5ⁱ—Co1—N3	90.73 (6)
C9—C8—C7	123.40 (16)	N3ⁱ—Co1—N3	180.0
C10—C9—C8	118.44 (17)	N5—Co1—N4	90.35 (6)
C10—C9—H9	120.8	N5ⁱ—Co1—N4	89.65 (6)
C8—C9—H9	120.8	N3ⁱ—Co1—N4	103.24 (5)
C11—C10—C9	119.22 (16)	N3—Co1—N4	76.76 (5)
C11—C10—H10	120.4	N5—Co1—N4ⁱ	89.65 (6)
C9—C10—H10	120.4	N5ⁱ—Co1—N4ⁱ	90.34 (6)
C10—C11—C12	119.01 (17)	N3ⁱ—Co1—N4ⁱ	76.76 (5)
C10—C11—H11	120.5	N3—Co1—N4ⁱ	103.24 (5)
C12—C11—H11	120.5	N4—Co1—N4ⁱ	180.0

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···N6ⁱⁱ	0.93	2.59	3.432 (3)	151
C11—H11···N7ⁱⁱⁱ	0.93	2.60	3.528 (3)	173
C10—H10···N1^iv	0.93	2.63	3.438 (2)	146

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

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements and Chouaib Doukkali University, El Jadida, Morocco, for financial support.

References

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