catena-Poly[[bis­[2-(1H-1,2,4-triazol-1-yl-κN ⁴)pyrazine]cadmium(II)]-di-μ-thio­cyanato-κ² S:N;κ² N:S]

Abstract

The title compound, [Cd(NCS)₂(C₆H₅N₅)₂]_n, is a coordination polymer with the Cd^II centre located on a twofold rotation axis. The Cd^II centre assumes a distorted octa­hedral geometry. The thio­cyanate anions function as bridging ligands between the Cd^II centres, leading to a chain-like arrangement expanding along [001].

Related literature

For a related structure, see: Yang & Shi (2008 ▶).

Experimental

Crystal data

• [Cd(NCS)₂(C₆H₅N₅)₂]

• M _r = 522.86

• Monoclinic,

• a = 25.818 (4) Å

• b = 7.4077 (10) Å

• c = 11.0276 (15) Å

• β = 113.843 (2)°

• V = 1929.1 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 1.38 mm⁻¹

• T = 298 K

• 0.41 × 0.21 × 0.20 mm

Data collection

• Bruker SMART APEX CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 1997 ▶) T _min = 0.602, T _max = 0.770

• 5381 measured reflections

• 2085 independent reflections

• 2005 reflections with I > 2σ(I)

• R _int = 0.022

Refinement

• R[F ² > 2σ(F ²)] = 0.022

• wR(F ²) = 0.058

• S = 1.10

• 2085 reflections

• 133 parameters

• H-atom parameters constrained

• Δρ_max = 0.35 e Å⁻³

• Δρ_min = −0.47 e Å⁻³

Data collection: SMART (Bruker, 1997 ▶); cell refinement: SAINT (Bruker, 1997 ▶); data reduction: SAINT; 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.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

2-(1H-1,2,4-triazol-1-yl)pyrazine is similar to 2-(pyrazol-1-yl)pyrazine (Yang & Shi, 2008) and therefore it should act as a brdiging ligand. We are interested in synthesizing complexes with mixed bridging ligands and selected thiocyanato and 2-(1H-1,2,4-triazol-1-yl)pyrazine as ligands. However, 2-(1H-1,2,4-triazol-1-yl)pyrazine only functions as a terminal ligand.

The coordination geometry of the Cd centres is shown in Fig. 1. The Cd atom is in a distorted octahedral CdN₄S₂ coordination geometry. In the crystal each Cd^II ion is surrounded by two other symmetry-related Cd^II ions with separation with 5.7105 (7) Å and the adjacent Cd^II ions were bridged by two thiocyanato anions and it forms a one-dimensional chain along the c axis. 2-(1H-1,2,4-triazol-1-yl)pyrazine only acts as a monodentate ligand.

Experimental

6 ml methanol solution of 2-(1H-1,2,4-triazol-1-yl)pyrazine (0.0345 g, 0.191 mmol), 5 ml C d(ClO₄)₂.6H₂O (0.0809 g, 0.193 mmol) H₂O solution and 5 ml NaSCN (0.0315 g, 0.389 mmol) H₂O solution were mixed together and stirred for a few minutes. The colorless single crystals were obtained after the filtrate had been allowed to stand at room temperature for two weeks.

Refinement

All H atoms were placed in calculated positions and refined as riding with C—H = 0.93 Å and U_iso(H) = 1.2U_eq(C).

Figures

Fig. 1.

Coordination around the Cd atom with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level. [Symmetry codes: (i) -x + 1, -y, -z + 1 (ii) -x + 1, y, -z + 3/2 (iii) x, -y, z + 1/2 (iv) -x + 1, -y, -z + 2]

Fig. 2.

Packing diagram of the title compound.

Crystal data

[Cd(NCS)2(C6H5N5)2]	F(000) = 1032
Mr = 522.86	Dx = 1.800 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 4306 reflections
a = 25.818 (4) Å	θ = 2.9–28.3°
b = 7.4077 (10) Å	µ = 1.38 mm−1
c = 11.0276 (15) Å	T = 298 K
β = 113.843 (2)°	Block, colourless
V = 1929.1 (5) Å3	0.41 × 0.21 × 0.20 mm
Z = 4

Data collection

Bruker SMART APEX CCD diffractometer	2085 independent reflections
Radiation source: fine-focus sealed tube	2005 reflections with I > 2σ(I)
graphite	Rint = 0.022
φ and ω scans	θmax = 27.0°, θmin = 1.7°
Absorption correction: multi-scan (SADABS; Bruker, 1997)	h = −32→23
Tmin = 0.602, Tmax = 0.770	k = −7→9
5381 measured reflections	l = −10→13

Refinement

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)] = 0.022	H-atom parameters constrained
wR(F2) = 0.058	w = 1/[σ2(Fo2) + (0.0298P)2 + 1.3229P] where P = (Fo2 + 2Fc2)/3
S = 1.10	(Δ/σ)max = 0.002
2085 reflections	Δρmax = 0.35 e Å−3
133 parameters	Δρmin = −0.47 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: 0.0082 (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
C1	0.43493 (9)	0.3626 (3)	0.9002 (2)	0.0392 (5)
H1	0.4636	0.3440	0.9838	0.047*
C2	0.39121 (9)	0.3614 (3)	0.6932 (2)	0.0382 (4)
H2	0.3808	0.3457	0.6027	0.046*
C3	0.56274 (8)	−0.1295 (3)	0.5829 (2)	0.0334 (4)
C4	0.30256 (8)	0.5013 (3)	0.68395 (18)	0.0322 (4)
C5	0.27688 (11)	0.5921 (3)	0.7544 (2)	0.0455 (5)
H5	0.2974	0.6177	0.8437	0.055*
C6	0.22301 (10)	0.5174 (4)	0.4984 (2)	0.0493 (5)
H6	0.2029	0.4949	0.4084	0.059*
C7	0.19638 (11)	0.6044 (3)	0.5671 (3)	0.0505 (6)
H7	0.1586	0.6371	0.5226	0.061*
Cd1	0.5000	0.10030 (3)	0.7500	0.03107 (10)
N1	0.43983 (7)	0.3119 (2)	0.78646 (17)	0.0391 (4)
N2	0.55550 (9)	−0.1113 (3)	0.47410 (19)	0.0455 (5)
N3	0.35900 (7)	0.4377 (2)	0.74783 (16)	0.0317 (3)
N4	0.38687 (8)	0.4394 (2)	0.88241 (17)	0.0377 (4)
N5	0.27701 (8)	0.4642 (3)	0.55708 (17)	0.0422 (4)
N6	0.22297 (9)	0.6433 (3)	0.6954 (2)	0.0535 (5)
S1	0.57240 (3)	−0.15916 (10)	0.73782 (5)	0.05367 (18)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0367 (11)	0.0455 (11)	0.0340 (10)	−0.0001 (9)	0.0129 (9)	−0.0018 (9)
C2	0.0371 (11)	0.0444 (11)	0.0356 (10)	0.0028 (9)	0.0172 (9)	−0.0052 (8)
C3	0.0287 (9)	0.0379 (10)	0.0307 (10)	0.0051 (7)	0.0089 (8)	−0.0017 (7)
C4	0.0329 (9)	0.0331 (9)	0.0335 (10)	0.0004 (7)	0.0162 (8)	0.0008 (7)
C5	0.0460 (13)	0.0563 (14)	0.0358 (11)	0.0117 (10)	0.0181 (10)	−0.0034 (9)
C6	0.0409 (12)	0.0649 (15)	0.0373 (11)	0.0040 (11)	0.0106 (9)	−0.0060 (10)
C7	0.0370 (12)	0.0666 (16)	0.0452 (14)	0.0126 (10)	0.0138 (11)	0.0007 (10)
Cd1	0.03018 (13)	0.03752 (14)	0.02687 (13)	0.000	0.01294 (9)	0.000
N1	0.0349 (9)	0.0439 (10)	0.0404 (9)	0.0014 (7)	0.0171 (7)	−0.0046 (8)
N2	0.0428 (10)	0.0607 (12)	0.0319 (10)	0.0058 (8)	0.0141 (8)	0.0017 (8)
N3	0.0321 (8)	0.0356 (8)	0.0300 (8)	−0.0009 (6)	0.0153 (7)	−0.0026 (6)
N4	0.0367 (9)	0.0465 (9)	0.0302 (9)	0.0006 (7)	0.0138 (7)	−0.0024 (7)
N5	0.0369 (9)	0.0549 (10)	0.0349 (9)	0.0035 (8)	0.0146 (7)	−0.0061 (8)
N6	0.0476 (11)	0.0696 (13)	0.0450 (11)	0.0190 (10)	0.0204 (9)	−0.0017 (10)
S1	0.0699 (4)	0.0614 (4)	0.0296 (3)	0.0323 (3)	0.0201 (3)	0.0093 (2)

Geometric parameters (Å, °)

C1—N4	1.306 (3)	C6—N5	1.337 (3)
C1—N1	1.363 (3)	C6—C7	1.372 (3)
C1—H1	0.9300	C6—H6	0.9300
C2—N1	1.313 (3)	C7—N6	1.331 (3)
C2—N3	1.334 (3)	C7—H7	0.9300
C2—H2	0.9300	Cd1—N2i	2.3031 (19)
C3—N2	1.145 (3)	Cd1—N2ii	2.3031 (19)
C3—S1	1.639 (2)	Cd1—N1iii	2.3528 (18)
C4—N5	1.312 (3)	Cd1—N1	2.3528 (17)
C4—C5	1.383 (3)	Cd1—S1iii	2.7220 (6)
C4—N3	1.418 (2)	Cd1—S1	2.7220 (6)
C5—N6	1.331 (3)	N2—Cd1ii	2.3031 (19)
C5—H5	0.9300	N3—N4	1.363 (2)
N4—C1—N1	114.71 (19)	N2ii—Cd1—N1	89.56 (7)
N4—C1—H1	122.6	N1iii—Cd1—N1	96.47 (9)
N1—C1—H1	122.6	N2i—Cd1—S1iii	96.54 (5)
N1—C2—N3	109.75 (19)	N2ii—Cd1—S1iii	86.34 (5)
N1—C2—H2	125.1	N1iii—Cd1—S1iii	173.10 (5)
N3—C2—H2	125.1	N1—Cd1—S1iii	87.01 (5)
N2—C3—S1	178.9 (2)	N2i—Cd1—S1	86.34 (5)
N5—C4—C5	123.5 (2)	N2ii—Cd1—S1	96.54 (5)
N5—C4—N3	115.64 (17)	N1iii—Cd1—S1	87.01 (5)
C5—C4—N3	120.82 (18)	N1—Cd1—S1	173.10 (5)
N6—C5—C4	120.5 (2)	S1iii—Cd1—S1	90.16 (4)
N6—C5—H5	119.7	C2—N1—C1	103.22 (18)
C4—C5—H5	119.7	C2—N1—Cd1	122.72 (14)
N5—C6—C7	121.9 (2)	C1—N1—Cd1	130.85 (14)
N5—C6—H6	119.1	C3—N2—Cd1ii	153.59 (19)
C7—C6—H6	119.1	C2—N3—N4	110.16 (17)
N6—C7—C6	122.0 (2)	C2—N3—C4	128.28 (17)
N6—C7—H7	119.0	N4—N3—C4	121.46 (16)
C6—C7—H7	119.0	C1—N4—N3	102.16 (16)
N2i—Cd1—N2ii	175.94 (10)	C4—N5—C6	115.50 (19)
N2i—Cd1—N1iii	89.56 (7)	C7—N6—C5	116.5 (2)
N2ii—Cd1—N1iii	87.73 (7)	C3—S1—Cd1	97.98 (7)
N2i—Cd1—N1	87.73 (7)

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