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Acta Crystallogr Sect E Struct Rep Online. 2010 January 1; 66(Pt 1): m19.
Published online 2009 December 4. doi:  10.1107/S1600536809051782
PMCID: PMC2980142

Dimethano­lbis[4,4,5,5-tetra­methyl-2-(5-methyl­imidazol-4-yl)-2-imidazoline-1-oxyl-3-oxide-κ2 O,N]cobalt(II) diperchlorate

Abstract

In the mononuclear title complex, [Co(C11H17N4O2)2(CH3OH)2](ClO4)2, the cobalt(II) atom lies on a symmetry centre and is coordinated by two O,N-bidentate ligands and two trans-arranged O atoms of the methanol mol­ecules in a slightly distorted octa­hedral geometry. In the crystal structure, cations and anions are linked by N—H(...)O and O—H(...)O hydrogen bonds into layers parallel to the bc plane.

Related literature

For the use of organic radicals as building blocks for the construction of new materials, see: Marvilliers et al. (1999 [triangle]); Yamamoto et al. (2001 [triangle]). For related structures, see: Chang et al. (2009 [triangle]); Zhang et al. (2007 [triangle]); Omata et al. (2001 [triangle]); Fokin et al. (2004 [triangle]); Wang et al. (2005 [triangle]). For the synthesis of the title compound, see: Ullman et al. (1970 [triangle], 1972 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-00m19-scheme1.jpg

Experimental

Crystal data

  • [Co(C11H17N4O2)2(CH4O)2](ClO4)2
  • M r = 796.49
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-00m19-efi1.jpg
  • a = 8.761 (3) Å
  • b = 9.030 (3) Å
  • c = 11.819 (4) Å
  • α = 88.470 (8)°
  • β = 85.260 (11)°
  • γ = 66.638 (7)°
  • V = 855.4 (5) Å3
  • Z = 1
  • Mo Kα radiation
  • μ = 0.73 mm−1
  • T = 295 K
  • 0.21 × 0.10 × 0.06 mm

Data collection

  • Bruker SMART APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996 [triangle]) T min = 0.862, T max = 0.959
  • 7639 measured reflections
  • 3880 independent reflections
  • 2629 reflections with I > 2σ(I)
  • R int = 0.035

Refinement

  • R[F 2 > 2σ(F 2)] = 0.058
  • wR(F 2) = 0.169
  • S = 1.02
  • 3880 reflections
  • 229 parameters
  • H-atom parameters constrained
  • Δρmax = 1.11 e Å−3
  • Δρmin = −0.70 e Å−3

Data collection: SMART (Bruker, 2002 [triangle]); cell refinement: SAINT (Bruker, 2002 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: publCIF (Westrip, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809051782/rz2401sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809051782/rz2401Isup2.hkl

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

Acknowledgments

This work was supported by the Natural Science Foundation and Basic Research Program of Henan province (No. 092300410195)

supplementary crystallographic information

Comment

Engineering of molecular magnets constitutes a major research goal and has spawned interest in organic radicals as building blocks for construction of new materials (Marvilliers et al., 1999; Yamamoto et al., 2001). In this field, nitronyl nitroxides acting as useful paramagnetic building blocks have been extensively used to assemble molecular magnetic materials, because many of them are good stable spin carriers even when coordinated to metal ions. Various substitutions on radical ligands can lead to large change in not only coordination modes but also electronic behaviours, so a large number of investigations on various properties of metal-radicals complexes have been carried out and aroused intense interest and far-ranging studies (Chang et al., 2009; Zhang et al., 2007; Omata et al., 2001; Fokin et al., 2004; Wang et al., 2005). In this article, we report the synthesis and crystal structure of a novel cobalt(II) complex with the nitronyl nitroxide radical.

The crystal structure of the title compound is shown in Figure. 1. The cobalt(II) ion lies on a symmetry centre and is six-coordinate in a slightly distorted octahedral CoN4O2 environment provided by two O,N-bidentate ligands and two trans-arranged oxygen atoms of methanol molecules. The Co1/O1/N3/C4/C1/N1 six-membered chelatating ring assumes a half-boat conformation, with atoms O1 and C1 displaced by 0.402 (3) and 0.195 (3) Å, respectively, from the mean plane of the other atoms. In the crystal structure, cations and anions are linked by N—H···O and O—H···O hydrogen bonds (Table 1) into layers parallel to the bc plane.

Experimental

The nitronyl nitroxide radical (4,4,5,5-tetramethyl-2-(5-methylimidazol-4-yl)-2-imidazoline-1-oxyl-3-oxide) was synthesized according to the literature procedures (Ullman et al., 1970; Ullman et al., 1972). The complex was synthesized by mixing 5 ml of a methanol solution of nitronyl nitroxide radical (0.4 mmol) and 5 ml of a methanol solution of Co(ClO4)2.6H2O (0.2 mmol). After stirring for two hours at room temperature, the mixture solution was filtered. The clear deep purple filtrate was diffused with diethyl ether vapour at room temperature for two days, to afford deep purple crystals suitable for X-ray analysis.

Refinement

The H atoms were positioned geometrically and refined using a riding-model approximation, with C—H = 0.93–0.96 Å, N—H = 0.86 Å, O—H = 0.85 Å, and with Uiso(H) = 1.2 Ueq(C, N) or 1.5 Ueq(C, O) for hydroxy and methyl H atoms.

Figures

Fig. 1.
The molecular structure of the title compound with the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. Unlabelled atoms are generated by the symmetry operation (-x+1,-y+1,-z+1).

Crystal data

[Co(C11H17N4O2)2(CH4O)2](ClO4)2Z = 1
Mr = 796.49F(000) = 415
Triclinic, P1Dx = 1.546 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.761 (3) ÅCell parameters from 1879 reflections
b = 9.030 (3) Åθ = 2.5–23.8°
c = 11.819 (4) ŵ = 0.73 mm1
α = 88.470 (8)°T = 295 K
β = 85.260 (11)°Block, purple
γ = 66.638 (7)°0.21 × 0.10 × 0.06 mm
V = 855.4 (5) Å3

Data collection

Bruker SMART APEXII CCD area-detector diffractometer3880 independent reflections
Radiation source: fine-focus sealed tube2629 reflections with I > 2σ(I)
graphiteRint = 0.035
phi and ω scansθmax = 27.5°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)h = −11→11
Tmin = 0.862, Tmax = 0.959k = −11→11
7639 measured reflectionsl = −14→15

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.058Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.169H-atom parameters constrained
S = 1.02w = 1/[σ2(Fo2) + (0.099P)2] where P = (Fo2 + 2Fc2)/3
3880 reflections(Δ/σ)max < 0.001
229 parametersΔρmax = 1.11 e Å3
0 restraintsΔρmin = −0.70 e Å3

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 takeninto account individually in the estimation of e.s.d.'s in distances, anglesand torsion angles; correlations between e.s.d.'s in cell parameters are onlyused 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)

xyzUiso*/Ueq
Co10.50000.50000.50000.0314 (2)
O10.7069 (3)0.5395 (3)0.44273 (19)0.0368 (6)
O20.6974 (3)0.6104 (4)0.0527 (2)0.0508 (7)
O30.1971 (5)0.1192 (5)0.3303 (3)0.0772 (10)
O40.3181 (5)0.0497 (4)0.1465 (3)0.0735 (10)
O50.0366 (5)0.1057 (6)0.1857 (4)0.1136 (16)
O60.2364 (6)−0.1310 (4)0.2532 (3)0.0897 (13)
O80.3412 (3)0.7434 (3)0.4682 (2)0.0479 (7)
H8D0.32540.78100.40150.072*
N10.4844 (3)0.4351 (3)0.3332 (2)0.0343 (6)
N20.4676 (4)0.2834 (4)0.1975 (3)0.0405 (7)
H20.43570.21950.16280.049*
N30.7304 (3)0.5838 (3)0.3387 (2)0.0303 (6)
N40.7347 (3)0.6110 (4)0.1542 (2)0.0373 (7)
C10.5901 (4)0.4399 (4)0.2393 (3)0.0314 (7)
C20.5821 (4)0.3431 (4)0.1536 (3)0.0347 (7)
C30.4138 (4)0.3410 (4)0.3035 (3)0.0396 (8)
H30.33590.31680.34980.048*
C40.6842 (4)0.5387 (4)0.2443 (3)0.0313 (7)
C50.7972 (4)0.7126 (4)0.3165 (3)0.0357 (8)
C60.8510 (5)0.6844 (5)0.1892 (3)0.0425 (9)
C70.6485 (6)0.8712 (5)0.3436 (5)0.0623 (12)
H7A0.56040.88080.29700.094*
H7B0.68170.95970.32870.094*
H7C0.60980.87310.42220.094*
C80.9369 (5)0.6878 (5)0.3931 (3)0.0502 (10)
H8A0.89040.71590.46980.075*
H8B0.99450.75510.36800.075*
H8C1.01360.57680.38980.075*
C90.8249 (7)0.8374 (6)0.1205 (4)0.0746 (15)
H9A0.86360.80890.04260.112*
H9B0.88630.89290.15060.112*
H9C0.70840.90650.12530.112*
C101.0289 (5)0.5579 (7)0.1667 (4)0.0648 (13)
H10A1.03820.45900.20350.097*
H10B1.10590.59600.19600.097*
H10C1.05440.53930.08640.097*
C110.6750 (5)0.2887 (5)0.0407 (3)0.0468 (9)
H11A0.66250.19350.01700.070*
H11B0.79110.26500.04620.070*
H11C0.63130.3726−0.01390.070*
C120.2019 (5)0.8318 (5)0.5434 (4)0.0537 (10)
H12A0.12200.78330.54540.081*
H12B0.15160.94100.51760.081*
H12C0.23750.83100.61810.081*
Cl10.19354 (13)0.03724 (13)0.22937 (9)0.0534 (3)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
Co10.0307 (3)0.0365 (4)0.0318 (4)−0.0185 (3)−0.0037 (2)0.0074 (3)
O10.0374 (12)0.0511 (15)0.0307 (12)−0.0268 (11)−0.0057 (10)0.0070 (11)
O20.0599 (17)0.0717 (19)0.0359 (14)−0.0412 (15)−0.0107 (12)0.0100 (13)
O30.099 (3)0.089 (3)0.061 (2)−0.056 (2)0.0030 (19)−0.0138 (19)
O40.088 (2)0.094 (3)0.063 (2)−0.064 (2)0.0018 (18)0.0024 (18)
O50.071 (2)0.141 (4)0.137 (4)−0.044 (3)−0.049 (3)0.023 (3)
O60.156 (4)0.072 (2)0.071 (2)−0.073 (3)−0.032 (2)0.0274 (18)
O80.0429 (14)0.0436 (14)0.0524 (16)−0.0128 (12)−0.0051 (12)0.0156 (12)
N10.0322 (14)0.0399 (16)0.0360 (16)−0.0196 (13)−0.0053 (12)0.0038 (12)
N20.0428 (16)0.0409 (16)0.0486 (18)−0.0268 (14)−0.0100 (14)0.0006 (14)
N30.0323 (13)0.0363 (14)0.0296 (14)−0.0213 (12)−0.0038 (11)0.0062 (11)
N40.0393 (16)0.0487 (17)0.0331 (15)−0.0267 (14)−0.0072 (12)0.0069 (13)
C10.0313 (16)0.0322 (17)0.0339 (17)−0.0157 (14)−0.0055 (13)0.0052 (13)
C20.0319 (16)0.0374 (18)0.0395 (19)−0.0177 (15)−0.0094 (14)0.0042 (15)
C30.0339 (17)0.044 (2)0.048 (2)−0.0229 (16)−0.0082 (15)0.0094 (17)
C40.0309 (16)0.0363 (17)0.0315 (17)−0.0185 (14)−0.0022 (13)0.0035 (14)
C50.0372 (18)0.0408 (19)0.0399 (19)−0.0267 (16)−0.0063 (14)0.0053 (15)
C60.048 (2)0.057 (2)0.039 (2)−0.0388 (19)−0.0089 (16)0.0105 (17)
C70.061 (3)0.044 (2)0.088 (3)−0.027 (2)−0.003 (2)−0.005 (2)
C80.053 (2)0.067 (3)0.050 (2)−0.043 (2)−0.0154 (18)0.008 (2)
C90.108 (4)0.085 (3)0.069 (3)−0.076 (3)−0.032 (3)0.040 (3)
C100.049 (2)0.095 (4)0.058 (3)−0.039 (3)0.010 (2)−0.017 (3)
C110.049 (2)0.052 (2)0.042 (2)−0.0218 (19)−0.0002 (17)−0.0075 (17)
C120.050 (2)0.043 (2)0.062 (3)−0.0106 (19)−0.012 (2)−0.0047 (19)
Cl10.0628 (6)0.0628 (6)0.0512 (6)−0.0409 (5)−0.0164 (5)0.0139 (5)

Geometric parameters (Å, °)

Co1—O1i2.042 (2)C2—C111.491 (5)
Co1—O12.042 (2)C3—H30.9300
Co1—N1i2.102 (3)C5—C81.524 (5)
Co1—N12.102 (3)C5—C71.526 (6)
Co1—O8i2.127 (3)C5—C61.537 (5)
Co1—O82.127 (3)C6—C91.530 (5)
O1—N31.308 (3)C6—C101.531 (6)
O2—N41.271 (4)C7—H7A0.9600
O3—Cl11.430 (3)C7—H7B0.9600
O4—Cl11.441 (3)C7—H7C0.9600
O5—Cl11.402 (4)C8—H8A0.9600
O6—Cl11.439 (3)C8—H8B0.9600
O8—C121.415 (5)C8—H8C0.9600
O8—H8D0.8501C9—H9A0.9600
N1—C31.302 (4)C9—H9B0.9600
N1—C11.396 (4)C9—H9C0.9600
N2—C31.343 (5)C10—H10A0.9600
N2—C21.376 (4)C10—H10B0.9600
N2—H20.8600C10—H10C0.9600
N3—C41.343 (4)C11—H11A0.9600
N3—C51.504 (4)C11—H11B0.9600
N4—C41.368 (4)C11—H11C0.9600
N4—C61.506 (4)C12—H12A0.9600
C1—C21.380 (5)C12—H12B0.9600
C1—C41.440 (4)C12—H12C0.9600
O1i—Co1—O1180.000 (1)N4—C6—C9109.6 (3)
O1i—Co1—N1i88.12 (10)N4—C6—C10107.2 (3)
O1—Co1—N1i91.88 (10)C9—C6—C10111.2 (4)
O1i—Co1—N191.88 (10)N4—C6—C5100.7 (3)
O1—Co1—N188.12 (10)C9—C6—C5114.9 (4)
N1i—Co1—N1180.0C10—C6—C5112.4 (3)
O1i—Co1—O8i91.60 (10)C5—C7—H7A109.5
O1—Co1—O8i88.40 (10)C5—C7—H7B109.5
N1i—Co1—O8i90.41 (11)H7A—C7—H7B109.5
N1—Co1—O8i89.59 (11)C5—C7—H7C109.5
O1i—Co1—O888.40 (10)H7A—C7—H7C109.5
O1—Co1—O891.60 (10)H7B—C7—H7C109.5
N1i—Co1—O889.59 (11)C5—C8—H8A109.5
N1—Co1—O890.41 (11)C5—C8—H8B109.5
O8i—Co1—O8180.00 (14)H8A—C8—H8B109.5
N3—O1—Co1122.87 (18)C5—C8—H8C109.5
C12—O8—Co1122.0 (2)H8A—C8—H8C109.5
C12—O8—H8D109.8H8B—C8—H8C109.5
Co1—O8—H8D122.5C6—C9—H9A109.5
C3—N1—C1105.6 (3)C6—C9—H9B109.5
C3—N1—Co1126.3 (2)H9A—C9—H9B109.5
C1—N1—Co1125.3 (2)C6—C9—H9C109.5
C3—N2—C2109.0 (3)H9A—C9—H9C109.5
C3—N2—H2125.5H9B—C9—H9C109.5
C2—N2—H2125.5C6—C10—H10A109.5
O1—N3—C4126.8 (3)C6—C10—H10B109.5
O1—N3—C5120.2 (2)H10A—C10—H10B109.5
C4—N3—C5112.6 (3)C6—C10—H10C109.5
O2—N4—C4125.5 (3)H10A—C10—H10C109.5
O2—N4—C6123.4 (3)H10B—C10—H10C109.5
C4—N4—C6111.0 (3)C2—C11—H11A109.5
C2—C1—N1109.8 (3)C2—C11—H11B109.5
C2—C1—C4131.0 (3)H11A—C11—H11B109.5
N1—C1—C4119.2 (3)C2—C11—H11C109.5
N2—C2—C1104.0 (3)H11A—C11—H11C109.5
N2—C2—C11121.3 (3)H11B—C11—H11C109.5
C1—C2—C11134.4 (3)O8—C12—H12A109.5
N1—C3—N2111.6 (3)O8—C12—H12B109.5
N1—C3—H3124.2H12A—C12—H12B109.5
N2—C3—H3124.2O8—C12—H12C109.5
N3—C4—N4107.6 (3)H12A—C12—H12C109.5
N3—C4—C1126.3 (3)H12B—C12—H12C109.5
N4—C4—C1126.1 (3)O5—Cl1—O3111.2 (3)
N3—C5—C8109.8 (3)O5—Cl1—O6110.4 (3)
N3—C5—C7105.0 (3)O3—Cl1—O6109.6 (2)
C8—C5—C7111.4 (3)O5—Cl1—O4109.4 (3)
N3—C5—C6100.1 (3)O3—Cl1—O4108.1 (2)
C8—C5—C6115.5 (3)O6—Cl1—O4108.0 (2)
C7—C5—C6113.8 (3)
N1i—Co1—O1—N3−151.2 (2)C5—N3—C4—N48.1 (4)
N1—Co1—O1—N328.8 (2)O1—N3—C4—C14.0 (5)
O8i—Co1—O1—N3118.5 (2)C5—N3—C4—C1−168.7 (3)
O8—Co1—O1—N3−61.5 (2)O2—N4—C4—N3−172.0 (3)
O1i—Co1—O8—C1239.5 (3)C6—N4—C4—N311.4 (4)
O1—Co1—O8—C12−140.5 (3)O2—N4—C4—C14.7 (6)
N1i—Co1—O8—C12−48.7 (3)C6—N4—C4—C1−171.8 (3)
N1—Co1—O8—C12131.3 (3)C2—C1—C4—N3−155.3 (3)
O1i—Co1—N1—C3−25.0 (3)N1—C1—C4—N325.4 (5)
O1—Co1—N1—C3155.0 (3)C2—C1—C4—N428.5 (6)
O8i—Co1—N1—C366.6 (3)N1—C1—C4—N4−150.8 (3)
O8—Co1—N1—C3−113.4 (3)O1—N3—C5—C841.8 (4)
O1i—Co1—N1—C1177.2 (3)C4—N3—C5—C8−145.0 (3)
O1—Co1—N1—C1−2.8 (3)O1—N3—C5—C7−78.0 (4)
O8i—Co1—N1—C1−91.2 (3)C4—N3—C5—C795.2 (4)
O8—Co1—N1—C188.8 (3)O1—N3—C5—C6163.8 (3)
Co1—O1—N3—C4−34.9 (4)C4—N3—C5—C6−23.0 (3)
Co1—O1—N3—C5137.3 (2)O2—N4—C6—C936.9 (5)
C3—N1—C1—C2−1.0 (4)C4—N4—C6—C9−146.5 (4)
Co1—N1—C1—C2160.5 (2)O2—N4—C6—C10−83.8 (4)
C3—N1—C1—C4178.4 (3)C4—N4—C6—C1092.7 (4)
Co1—N1—C1—C4−20.1 (4)O2—N4—C6—C5158.4 (3)
C3—N2—C2—C1−0.7 (4)C4—N4—C6—C5−25.0 (4)
C3—N2—C2—C11174.6 (3)N3—C5—C6—N426.4 (3)
N1—C1—C2—N21.0 (4)C8—C5—C6—N4144.2 (3)
C4—C1—C2—N2−178.3 (3)C7—C5—C6—N4−85.1 (3)
N1—C1—C2—C11−173.3 (4)N3—C5—C6—C9144.0 (3)
C4—C1—C2—C117.4 (6)C8—C5—C6—C9−98.1 (4)
C1—N1—C3—N20.6 (4)C7—C5—C6—C932.5 (4)
Co1—N1—C3—N2−160.7 (2)N3—C5—C6—C10−87.4 (3)
C2—N2—C3—N10.0 (4)C8—C5—C6—C1030.4 (4)
O1—N3—C4—N4−179.2 (3)C7—C5—C6—C10161.1 (3)

Symmetry codes: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N2—H2···O40.862.182.988 (4)156
O8—H8D···O6ii0.851.992.828 (4)167

Symmetry codes: (ii) x, y+1, z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RZ2401).

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