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Acta Cryst. (2009). E65, m431    [ doi:10.1107/S1600536809005686 ]

Poly[bis(cyanato-[kappa]N)bis([mu]-pyrazine-[kappa]2N:N')cobalt(II)]

M. Wriedt, I. Jess and C. Näther

Abstract top

In the crystal structure of the title compound, [Co(NCO)2(C4H4N2)2]n, the Co(II) cation is coordinated by four N-bonded pyrazine ligands and two N-bonded cyanate anions in a slightly distorted octahedral geometry. The crystal structure consists of [mu]-N:N' pyrazine-bridged cobalt cyanate chains; these are further linked by additional [mu]-N:N'-bridging pyrazine ligands into layers, which are stacked perpendicular to the crystallographic a axis. The C and O atoms in both crystallographic independent cyanate anions are disordered in two orientations and were refined using a split model with site occupation factor ratios of 0.75/0.25 and 0.7/0.3.

Comment top

In our investigations we have recently demonstrated that new ligand deficient coordination polymers with interestic magnetic properties can be prepared by thermal decomposition of suitable ligand rich precursor compounds (Näther & Greve, 2003; Wriedt et al., 2009). In order to prepare additional ligand rich precursor compounds we have reacted cobalt(II) nitrate hexahydrate and potassium cyanate with pyrazine in a methanol water mixture. In this reaction single crystals of the title compound were obtained in an inhomogenous mixture containing additional unknown phases.

In the crystal structure of the 1:2 title compound [Co(OCN)2(pyrazine)2]n the cobalt(II) cations are coordinated by four pyrazine ligands and two thiocyanate anions within slightly distorted octahedra (Fig. 1). The cobalt cations are µ-1,4-(N,N) bridged by the pyrazine ligands forming layers, which are stacked perpendicular to the crystallographic a-axis (Fig. 2). The cyanate anions do not act as bridging ligands and are only terminal N-bonded to the metal center. A similar structural motif is observed in the structures of the 1:2 thiocyanate compounds of composition [M(SCN)2(pyrazine)2]n (M = Mn, Fe, Co, Ni) reported recently (Lloret et al., 1999; Real et al., 1991; Lu et al.., 1997; Wriedt et al., 2009). The Co—NCO distances amount to 2.039 (3) and 2.059 (3) Å and are significantly shorter as the Co—Npyrazine distances, which range from 2.191 (3) to 2.200 (3) Å. The angles around the cobalt cations range between 89.23 (12) and 179.58 (12)° (Tab. 1). The shortest intra- and interchain Co···Co distances amount to 7.1721 (4) and 8.2170 (5) Å, respectively.

Related literature top

For related pyrazine structures, see: Lloret et al. (1999); Real et al. (1991); Lu et al. (1997); Wriedt et al. (2009). For general background, see: Näther & Greve (2003); Näther et al. (2003); Wriedt et al. (2008, 2009); Näther et al. (2007); Näther & Jeß (2004).

Experimental top

Co(NO3)2.6H2O, pyrazine and methanol were obtained from Alfa Aesar as well as KOCN was obtained from Fluka. 0.5 mmol (145.5 mg) Co(NO3)2.6H2O, 1 mmol (81.1 mg) KOCN, 0.5 mmol (40.1 mg) pyrazine, 0.5 mL methanol and 0.5 mL water were transfered in a closed test-tube. The mixture was heated at 120 °C for three days. After cooling yellow block-shaped single crystals of the title compound were obtained in a heterogenous mixture.

Refinement top

All H atoms were located in a difference map but they were positioned with idealized geometry and were refined with Ueq(H) = 1.2 Ueq(C) using a riding model with C—H = 0.95 Å.

The C and O atoms in both crystallographic independent cyanate anions are disordered in two orientations and were refined using a split model. In one of the two anions, the C and O atoms of lower occupancy were refined only isotropically. They were refined by a split model with site occupation factor ratios of 0.75/0.25 and 0.7/0.3.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2008); cell refinement: X-AREA (Stoe & Cie, 2008); data reduction: X-AREA (Stoe & Cie, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: XCIF in SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Crystal structure of the title compound with labelling and displacement ellipsoids drawn at the 50% probability level. The disorder of the cyanate anions is not show for clarity. [Symmetry codes: (i) x, -y+1, z-1/2; (ii) x, -y+2, z+1/2.]
[Figure 2] Fig. 2. Crystal structure of the title compound with view along the a-axis.
Poly[bis(cyanato-κN)bis(µ-pyrazine-κ2N:N')cobalt(II)] top
Crystal data top
[Co(NCO)2(C4H4N2)2]F(000) = 1224
Mr = 303.15Dx = 1.579 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 8000 reflections
a = 25.5712 (17) Åθ = 14.1–25.9°
b = 10.1230 (8) ŵ = 1.35 mm−1
c = 10.1863 (7) ÅT = 170 K
β = 104.763 (8)°Block, yellow
V = 2549.8 (3) Å30.24 × 0.14 × 0.07 mm
Z = 8
Data collection top
Stoe IPDS-1
diffractometer		2684 independent reflections
Radiation source: fine-focus sealed tube2058 reflections with I > 2σ(I)
graphiteRint = 0.039
φ scansθmax = 27.1°, θmin = 2.9°
Absorption correction: numerical
(X-SHAPE and X-RED32; Stoe & Cie, 2008)		h = −32→32
Tmin = 0.789, Tmax = 0.903k = −12→12
11369 measured reflectionsl = −13→13
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.139H-atom parameters constrained
S = 1.04 w = 1/[σ2(Fo2) + (0.0575P)2 + 18.631P]
where P = (Fo2 + 2Fc2)/3
2684 reflections(Δ/σ)max = 0.001
198 parametersΔρmax = 0.71 e Å−3
0 restraintsΔρmin = −1.17 e Å−3
Crystal data top
[Co(NCO)2(C4H4N2)2]V = 2549.8 (3) Å3
Mr = 303.15Z = 8
Monoclinic, C2/cMo Kα radiation
a = 25.5712 (17) ŵ = 1.35 mm−1
b = 10.1230 (8) ÅT = 170 K
c = 10.1863 (7) Å0.24 × 0.14 × 0.07 mm
β = 104.763 (8)°
Data collection top
Stoe IPDS-1
diffractometer		2684 independent reflections
Absorption correction: numerical
(X-SHAPE and X-RED32; Stoe & Cie, 2008)		2058 reflections with I > 2σ(I)
Tmin = 0.789, Tmax = 0.903Rint = 0.039
11369 measured reflectionsθmax = 27.1°
Refinement top
R[F2 > 2σ(F2)] = 0.051 w = 1/[σ2(Fo2) + (0.0575P)2 + 18.631P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.139Δρmax = 0.71 e Å−3
S = 1.04Δρmin = −1.17 e Å−3
2684 reflectionsAbsolute structure: ?
198 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
H-atom parameters constrained
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
xyzUiso*/UeqOcc. (<1)
Co10.629290 (19)0.75059 (4)0.63502 (4)0.01326 (17)
N10.62838 (13)0.5943 (3)0.7846 (3)0.0162 (6)
C10.66193 (17)0.5983 (3)0.9072 (4)0.0224 (8)
H10.68680.66950.92970.027*
C20.66194 (17)0.5014 (4)1.0044 (3)0.0224 (8)
H20.68640.50881.09160.027*
N20.62829 (13)0.3981 (3)0.9778 (3)0.0171 (6)
C30.59444 (17)0.3935 (4)0.8537 (3)0.0230 (8)
H30.57000.32150.83050.028*
C40.59412 (17)0.4920 (4)0.7578 (4)0.0225 (8)
H40.56900.48640.67140.027*
N110.63140 (13)0.9093 (3)0.4902 (3)0.0163 (6)
C110.67047 (17)0.9151 (4)0.4247 (4)0.0228 (8)
H110.69920.85280.44610.027*
C120.67008 (17)1.0102 (3)0.3260 (4)0.0222 (8)
H120.69841.01100.28100.027*
N120.63094 (13)1.1005 (3)0.2930 (3)0.0167 (6)
C130.59214 (17)1.0958 (4)0.3588 (4)0.0259 (9)
H130.56371.15900.33810.031*
C140.59239 (18)1.0000 (4)0.4575 (4)0.0259 (9)
H140.56410.99930.50250.031*
N210.54684 (14)0.7557 (3)0.5817 (3)0.0238 (7)
C210.5047 (3)0.7083 (8)0.5445 (8)0.0347 (16)0.75
O210.4602 (3)0.6596 (9)0.5110 (10)0.109 (4)0.75
O21'0.4627 (6)0.7506 (17)0.4184 (18)0.052 (4)0.25
C21'0.5054 (9)0.7583 (16)0.498 (2)0.023 (4)0.25
N310.71251 (14)0.7443 (3)0.6873 (3)0.0218 (7)
C310.7539 (3)0.7288 (7)0.7698 (8)0.0250 (15)0.70
O310.7962 (3)0.7135 (8)0.8513 (7)0.074 (3)0.70
C31'0.7530 (9)0.7621 (19)0.734 (2)0.030 (6)*0.30
O31'0.8018 (11)0.771 (2)0.789 (3)0.098 (8)*0.30
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Co10.0272 (3)0.0060 (2)0.0076 (2)−0.00033 (18)0.00627 (18)0.00004 (16)
N10.0307 (18)0.0095 (13)0.0085 (13)−0.0035 (11)0.0050 (13)0.0015 (10)
C10.037 (2)0.0124 (16)0.0150 (16)−0.0096 (15)0.0022 (16)0.0021 (13)
C20.037 (2)0.0160 (17)0.0103 (15)−0.0053 (15)−0.0003 (16)0.0024 (13)
N20.0319 (18)0.0090 (13)0.0093 (13)−0.0019 (11)0.0033 (13)0.0010 (10)
C30.039 (2)0.0161 (17)0.0119 (16)−0.0099 (15)0.0021 (16)0.0006 (13)
C40.036 (2)0.0161 (17)0.0110 (15)−0.0066 (15)−0.0009 (16)0.0028 (13)
N110.0312 (18)0.0083 (13)0.0119 (13)0.0028 (11)0.0100 (13)0.0027 (10)
C110.036 (2)0.0137 (17)0.0241 (18)0.0075 (15)0.0172 (17)0.0096 (14)
C120.036 (2)0.0147 (16)0.0220 (17)0.0080 (15)0.0182 (17)0.0087 (14)
N120.0331 (18)0.0079 (13)0.0129 (14)0.0033 (11)0.0126 (14)0.0015 (10)
C130.041 (2)0.0177 (18)0.0257 (19)0.0137 (16)0.0198 (19)0.0117 (15)
C140.039 (2)0.0179 (18)0.0278 (19)0.0093 (16)0.0216 (18)0.0111 (15)
N210.0311 (18)0.0192 (16)0.0204 (15)−0.0023 (14)0.0056 (16)−0.0001 (12)
C210.034 (4)0.032 (4)0.040 (4)0.000 (3)0.014 (3)−0.027 (3)
O210.041 (4)0.137 (8)0.152 (8)−0.033 (4)0.031 (5)−0.114 (7)
O21'0.027 (7)0.061 (11)0.055 (9)0.012 (7)−0.016 (8)−0.038 (8)
C21'0.040 (12)0.004 (8)0.023 (9)0.001 (7)0.003 (9)0.004 (6)
N310.0318 (18)0.0171 (16)0.0183 (15)0.0012 (13)0.0099 (15)−0.0002 (12)
C310.038 (4)0.018 (3)0.016 (3)0.007 (3)0.001 (3)−0.010 (3)
O310.052 (4)0.089 (5)0.055 (4)0.036 (4)−0.031 (4)−0.053 (4)
Geometric parameters (Å, °) top
Co1—N212.039 (3)N11—C111.337 (5)
Co1—N312.059 (3)C11—C121.390 (5)
Co1—N112.191 (3)C11—H110.9500
Co1—N2i2.193 (3)C12—N121.333 (5)
Co1—N12ii2.197 (3)C12—H120.9500
Co1—N12.200 (3)N12—C131.332 (5)
N1—C11.324 (5)N12—Co1iv2.197 (3)
N1—C41.339 (5)C13—C141.397 (5)
C1—C21.394 (5)C13—H130.9500
C1—H10.9500C14—H140.9500
C2—N21.337 (5)N21—C211.151 (8)
C2—H20.9500N21—C21'1.18 (2)
N2—C31.338 (5)C21—O211.206 (9)
N2—Co1iii2.193 (3)O21'—C21'1.19 (3)
C3—C41.395 (5)N31—C31'1.04 (2)
C3—H30.9500N31—C311.182 (8)
C4—H40.9500C31—O311.195 (9)
N11—C141.334 (5)C31'—O31'1.24 (4)
N21—Co1—N31179.45 (13)N1—C4—H4119.2
N21—Co1—N1190.19 (12)C3—C4—H4119.2
N31—Co1—N1189.76 (12)C14—N11—C11116.8 (3)
N21—Co1—N2i90.23 (12)C14—N11—Co1121.8 (2)
N31—Co1—N2i89.23 (12)C11—N11—Co1121.2 (2)
N11—Co1—N2i90.53 (11)N11—C11—C12121.5 (3)
N21—Co1—N12ii90.19 (12)N11—C11—H11119.2
N31—Co1—N12ii90.35 (12)C12—C11—H11119.2
N11—Co1—N12ii89.45 (10)N12—C12—C11121.6 (3)
N2i—Co1—N12ii179.58 (12)N12—C12—H12119.2
N21—Co1—N190.57 (12)C11—C12—H12119.2
N31—Co1—N189.49 (12)C13—N12—C12117.1 (3)
N11—Co1—N1178.55 (11)C13—N12—Co1iv121.0 (2)
N2i—Co1—N190.70 (10)C12—N12—Co1iv121.9 (2)
N12ii—Co1—N189.32 (10)N12—C13—C14121.3 (3)
C1—N1—C4116.7 (3)N12—C13—H13119.3
C1—N1—Co1120.9 (2)C14—C13—H13119.3
C4—N1—Co1122.5 (2)N11—C14—C13121.6 (3)
N1—C1—C2122.1 (3)N11—C14—H14119.2
N1—C1—H1118.9C13—C14—H14119.2
C2—C1—H1118.9C21—N21—C21'34.7 (8)
N2—C2—C1121.5 (3)C21—N21—Co1153.4 (5)
N2—C2—H2119.3C21'—N21—Co1150.6 (11)
C1—C2—H2119.3N21—C21—O21177.2 (8)
C2—N2—C3116.5 (3)N21—C21'—O21'174 (2)
C2—N2—Co1iii120.1 (2)C31'—N31—C3124.8 (10)
C3—N2—Co1iii123.4 (2)C31'—N31—Co1163.3 (12)
N2—C3—C4121.6 (3)C31—N31—Co1150.1 (5)
N2—C3—H3119.2N31—C31—O31178.7 (10)
C4—C3—H3119.2N31—C31'—O31'174 (2)
N1—C4—C3121.6 (3)
Symmetry codes: (i) x, −y+1, z−1/2; (ii) x, −y+2, z+1/2; (iii) x, −y+1, z+1/2; (iv) x, −y+2, z−1/2.
Table 1
Selected geometric parameters (Å, °) top
Co1—N212.039 (3)Co1—N2i2.193 (3)
Co1—N312.059 (3)Co1—N12ii2.197 (3)
Co1—N112.191 (3)Co1—N12.200 (3)
N21—Co1—N31179.45 (13)N11—Co1—N12ii89.45 (10)
N21—Co1—N1190.19 (12)N2i—Co1—N12ii179.58 (12)
N31—Co1—N1189.76 (12)N21—Co1—N190.57 (12)
N21—Co1—N2i90.23 (12)N31—Co1—N189.49 (12)
N31—Co1—N2i89.23 (12)N11—Co1—N1178.55 (11)
N11—Co1—N2i90.53 (11)N2i—Co1—N190.70 (10)
N21—Co1—N12ii90.19 (12)N12ii—Co1—N189.32 (10)
N31—Co1—N12ii90.35 (12)
Symmetry codes: (i) x, −y+1, z−1/2; (ii) x, −y+2, z+1/2.
Acknowledgements top

MW thanks the Stiftung Stipendien-Fonds des Verbandes der Chemischen Industrie and the Studienstiftung des deutschen Volkes for a PhD scholarship. We gratefully acknowledge financial support by the State of Schleswig-Holstein and we thank Professor Dr Wolfgang Bensch for the opportunity to use his experimental facility.

references
References top

Lloret, F., Julve, M., Cano, J. & Munno, G. D. (1999). Mol. Cryst. Liq. Cryst. 334, 569–585.

Lu, J., Paliwala, T., Lim, S. C., Yu, C., Niu, T. & Jacobson, A. J. (1997). Inorg. Chem. 36, 923–929.

Näther, C., Bhosekar, G. & Je\&s, I. (2007). Eur. J. Inorg. Chem. pp. 5353–5359.

Näther, C. & Greve, J. (2003). J. Solid State Chem. 176, 259–265.

Näther, C. & Je\&s, I. (2004). Eur. J. Inorg. Chem. pp. 2868–2876.

Näther, C., Wriedt, M. & Je\&s, I. (2003). Inorg. Chem. 42, 2391–2397.

Real, J. A., Munno, G. D., Munoz, M. C. & Julve, M. (1991). Inorg. Chem. 30, 2701–2704.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Stoe & Cie (2008). X-AREA, X-RED32 and X-SHAPE. Stoe & Cie, Darmstadt, Germany.

Wriedt, M., Je\&s, I. & Näther, C. (2008). Eur. J. Inorg. Chem. pp. 363–372.

Wriedt, M., Je\&s, I. & Näther, C. (2009). Eur. J. Inorg. Chem. In the press.