fac-Tris(pyridine-2-carboxyl­ato-κ2N,O)cobalt(III)

Golenia, I.A.; Boyko, A.N.; Kotova, N.V.; Haukka, M.; Kalibabchuk, V.A.

doi:10.1107/S1600536811043303

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 11| November 2011| Pages m1596-m1597

doi:10.1107/S1600536811043303

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fac-Tris(pyridine-2-carboxylato-κ²N,O)cobalt(III)

Irina A. Golenia,^a Alexander N. Boyko,^a Natalia V. Kotova,^a Matti Haukka ^b and Valentina A. Kalibabchuk ^c ^*

^aDepartment of Chemistry, Kiev National Taras Shevchenko University, Volodymyrska Street 64, 01601 Kiev, Ukraine, ^bDepartment of Chemistry, University of Joensuu, PO Box 111, FI-80101 Joensuu, Finland, and ^cDepartment of General Chemistry, O. O. Bohomolets National Medical University, Shevchenko Boulevard 13, 01601 Kiev, Ukraine
^*Correspondence e-mail: kalibabchuk@ukr.net

(Received 11 October 2011; accepted 19 October 2011; online 29 October 2011)

In the title compound, [Co(C₆H₄NO₂)₃], the Co^III ion lies on a threefold rotation axis and is in a distorted octahedral environment defined by three N and three O donor atoms from three fac-disposed pyridine-2-carboxylate ligands. The ligands are coordinated in a chelate fashion, forming three five-membered rings. In the crystal, translationally related complex molecules are organized into columns along [001] via C—H⋯O hydrogen bonds.

Related literature

For the use of hydroxamate ligands in the synthesis of polynuclear compounds, see: Dobosz et al. (1999 ); Fritsky et al. (1998 ); Sachse et al. (2008 ). For hydrolytic destruction of hydroxamate ligands upon complex formation, see: Świątek-Kozłowska et al. (2000 ). For related structures, see: Fritsky et al. (2001 ); Fu & Wang (2005 ); Kovbasyuk et al. (2004 ); Krämer & Fritsky (2000 ); Mokhir et al. (2002 ); Moroz et al. (2010 ); Pelizzi & Pelizzi (1981 ); Sliva et al. (1997 ); Wörl, Fritsky et al. (2005 ); Wörl, Pritzkow et al. (2005 ). For the synthesis of pyridine-2-hydroxamic acid, see: Hynes (1970 ).

Experimental

Crystal data

[Co(C₆H₄NO₂)₃]
M_r = 425.24
Hexagonal, P 6
a = 12.8617 (12) Å
c = 6.2122 (9) Å
V = 890.0 (2) Å³
Z = 2
Mo Kα radiation
μ = 1.01 mm⁻¹
T = 120 K
0.23 × 0.08 × 0.03 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997 ) T_min = 0.800, T_max = 0.970
5635 measured reflections
978 independent reflections
893 reflections with I > 2σ(I)
R_int = 0.043

Refinement

R[F² > 2σ(F²)] = 0.068
wR(F²) = 0.197
S = 1.16
978 reflections
86 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 1.05 e Å⁻³
Δρ_min = −0.59 e Å⁻³
Absolute structure: Flack (1983 ), 400 Friedel pairs
Flack parameter: −0.02 (7)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O2ⁱ	0.95	2.60	3.212 (14)	123
Symmetry code: (i) x-y+1, x, z-1.

Data collection: COLLECT (Nonius, 1998 ); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: DIAMOND (Brandenburg, 1999 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811043303/hy2479sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811043303/hy2479Isup2.hkl

checkCIF report

Comment top

Hydroxamic groups and their derivatives are often used in syntheses of polynuclear metal complexes (Dobosz et al., 1999; Fritsky et al., 1998; Sachse et al., 2008). However, functionalized hydroxamate ligands having additional donor functions often undergo hydrolytic destruction when complex formation with 3d-metal ions takes place (Dobosz et al., 1999; Świątek-Kozłowska et al., 2000). As a result, a carboxylic group is formed. The title compound was obtained as a result of hydrolytic decomposition of pyridine-2-hydroxamic acid during the reaction of complex formation with cobalt(II) perchlorate.

In the title compound, the Co^III ion lies on a threefold rotation axis and is in a distorted octahedral environment of three N and three O donor atoms from three pyridine-2-carboxylate ligands (Fig. 1). Unlike in the case of earlier reported tris(pyridine-2-carboxylato)cobalt(III) monohydrate, in which the realization of mer-isomer is observed, in the title complex three pyridine-2-carboxylate ligands are disposed in a fac-fashion (Fu & Wang, 2005; Pelizzi & Pelizzi, 1981). The ligands are coordinated in a chelate mode, forming three five-membered rings. The Co—N and Co—O bond lengths are consistent with the values typically quoted for the octahedral cobalt(III) complexes with N,O-mixed donor ligands (Mokhir et al., 2002; Sliva et al., 1997). The C—O bond lengths in the deprotonated carboxylate groups of the ligands differ significantly [1.232 (14) and 1.339 (15) Å], which is typical for monodentately coordinated carboxylates (Wörl, Fritsky et al., 2005; Wörl, Pritzkow et al., 2005). The C—C and C—N bond lengths in the pyridine rings are normal for 2-substituted pyridine derivatives (Fritsky et al., 2001; Kovbasyuk et al., 2004; Krämer & Fritsky, 2000; Moroz et al., 2010).

In the crystal, the translational complex molecules are organized into columns along the c axis (Fig. 2). The neighboring molecules are united by C—H···O hydrogen bonds (Table 1).

Related literature top

For the use of hydroxamate ligands in the synthesis of polynuclear compounds, see: Dobosz et al. (1999); Fritsky et al. (1998); Sachse et al. (2008). For hydrolytic destruction of hydroxamate ligands upon complex formation, see: Świątek-Kozłowska et al. (2000). For related structures, see: Fritsky et al. (2001); Fu & Wang (2005); Kovbasyuk et al. (2004); Krämer & Fritsky (2000); Mokhir et al. (2002); Moroz et al. (2010); Pelizzi & Pelizzi (1981); Sliva et al. (1997); Wörl, Fritsky et al. (2005); Wörl, Pritzkow et al. (2005). For the synthesis of pyridine-2-hydroxamic acid, see: Hynes (1970).

Experimental top

Cobalt(II) perchlorate hexahydrate (0.0365 g, 0.1 mmol) was dissolved in water (3 ml) and mixed with a solution of pyridine-2-hydroxamic acid (0.0414 g, 0.3 mmol) (Hynes, 1970) in methanol (3 ml). The resulting clear red solution was set aside for crystallization by slow diffusion of diethyl ether into the formed solution. The pink crystals formed in 5–7 days were filtered off, washed with diethyl ether and air-dried (yield: 83%).

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR2004 (Burla et al., 2005); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure of the title compound. Displacement ellipsoids are shown at the 50% probability level. [Symmetry codes: (i) -x+y, 1-x, z; (ii) 1-y, 1+x-y, z.]
	Fig. 2. A packing diagram of the title compound. H atoms have been omitted for clarity.

fac-Tris(pyridine-2-carboxylato-κ²N,O)cobalt(III) top

Crystal data top

[Co(C₆H₄NO₂)₃]	D_x = 1.587 Mg m⁻³
M_r = 425.24	Mo Kα radiation, λ = 0.71073 Å
Hexagonal, P6	Cell parameters from 713 reflections
Hall symbol: P 6	θ = 3.2–24.5°
a = 12.8617 (12) Å	µ = 1.01 mm⁻¹
c = 6.2122 (9) Å	T = 120 K
V = 890.0 (2) Å³	Block, pink
Z = 2	0.23 × 0.08 × 0.03 mm
F(000) = 432

Data collection top

Nonius KappaCCD diffractometer	978 independent reflections
Radiation source: fine-focus sealed tube	893 reflections with I > 2σ(I)
Horizontally mounted graphite crystal monochromator	R_int = 0.043
Detector resolution: 9 pixels mm^-1	θ_max = 25.0°, θ_min = 3.2°
ϕ and ω scans with κ offset	h = −15→15
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997)	k = −15→15
T_min = 0.800, T_max = 0.970	l = −7→7
5635 measured reflections

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)] = 0.068	H-atom parameters constrained
wR(F²) = 0.197	w = 1/[σ²(F_o²) + (0.1316P)² + 0.9442P] where P = (F_o² + 2F_c²)/3
S = 1.16	(Δ/σ)_max < 0.001
978 reflections	Δρ_max = 1.05 e Å⁻³
86 parameters	Δρ_min = −0.59 e Å⁻³
1 restraint	Absolute structure: Flack (1983), 400 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.02 (7)

Crystal data top

[Co(C₆H₄NO₂)₃]	Z = 2
M_r = 425.24	Mo Kα radiation
Hexagonal, P6	µ = 1.01 mm⁻¹
a = 12.8617 (12) Å	T = 120 K
c = 6.2122 (9) Å	0.23 × 0.08 × 0.03 mm
V = 890.0 (2) Å³

Data collection top

Nonius KappaCCD diffractometer	978 independent reflections
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997)	893 reflections with I > 2σ(I)
T_min = 0.800, T_max = 0.970	R_int = 0.043
5635 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.068	H-atom parameters constrained
wR(F²) = 0.197	Δρ_max = 1.05 e Å⁻³
S = 1.16	Δρ_min = −0.59 e Å⁻³
978 reflections	Absolute structure: Flack (1983), 400 Friedel pairs
86 parameters	Absolute structure parameter: −0.02 (7)
1 restraint

Special details top

Experimental. The final structural refinement was performed by using the twin law -1 -1 0 0 1 0 0 0 -1 with the final BASF parameter refining to 0.80178.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Co1	0.3333	0.6667	0.3408 (2)	0.0379 (5)
O1	0.4550 (7)	0.7860 (7)	0.5147 (11)	0.0514 (18)
O2	0.6490 (9)	0.8907 (8)	0.5627 (16)	0.083 (3)
N1	0.4619 (6)	0.6785 (6)	0.1705 (12)	0.0332 (15)
C1	0.4622 (10)	0.6303 (9)	−0.0009 (17)	0.051 (2)
H1	0.3875	0.5756	−0.0656	0.061*
C2	0.5687 (9)	0.6533 (9)	−0.1037 (17)	0.050 (2)
H2	0.5659	0.6145	−0.2355	0.061*
C3	0.6747 (10)	0.7308 (9)	−0.0138 (18)	0.052 (2)
H3	0.7483	0.7480	−0.0795	0.062*
C4	0.6729 (9)	0.7796 (9)	0.159 (2)	0.052 (3)
H4	0.7469	0.8358	0.2241	0.062*
C5	0.5690 (8)	0.7548 (9)	0.2577 (18)	0.048 (2)
C6	0.5660 (11)	0.8159 (9)	0.4512 (18)	0.057 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0513 (7)	0.0513 (7)	0.0111 (8)	0.0256 (3)	0.000	0.000
O1	0.067 (4)	0.066 (4)	0.018 (4)	0.031 (4)	−0.007 (3)	−0.008 (3)
O2	0.105 (7)	0.067 (5)	0.054 (6)	0.027 (4)	−0.036 (5)	0.004 (4)
N1	0.045 (4)	0.047 (4)	0.014 (3)	0.028 (3)	−0.001 (3)	0.007 (3)
C1	0.065 (5)	0.056 (5)	0.034 (5)	0.031 (4)	0.006 (4)	0.008 (4)
C2	0.061 (5)	0.058 (5)	0.041 (6)	0.036 (5)	0.010 (4)	0.006 (4)
C3	0.060 (6)	0.059 (6)	0.046 (6)	0.038 (5)	0.014 (5)	0.016 (5)
C4	0.042 (5)	0.067 (6)	0.055 (7)	0.033 (4)	0.012 (5)	0.023 (6)
C5	0.048 (5)	0.057 (5)	0.042 (6)	0.029 (4)	−0.005 (4)	0.021 (5)
C6	0.071 (7)	0.052 (6)	0.036 (6)	0.021 (5)	−0.027 (6)	0.010 (5)

Geometric parameters (Å, º) top

Co1—O1ⁱ	1.889 (7)	C1—C2	1.402 (14)
Co1—O1	1.889 (7)	C1—H1	0.9500
Co1—O1ⁱⁱ	1.889 (7)	C2—C3	1.344 (16)
Co1—N1ⁱ	1.904 (7)	C2—H2	0.9500
Co1—N1ⁱⁱ	1.904 (7)	C3—C4	1.251 (15)
Co1—N1	1.904 (7)	C3—H3	0.9500
O1—C6	1.339 (15)	C4—C5	1.354 (14)
O2—C6	1.232 (14)	C4—H4	0.9500
N1—C1	1.233 (14)	C5—C6	1.447 (15)
N1—C5	1.343 (12)

O1ⁱ—Co1—O1	90.6 (3)	N1—C1—C2	122.4 (10)
O1ⁱ—Co1—O1ⁱⁱ	90.6 (3)	N1—C1—H1	118.8
O1—Co1—O1ⁱⁱ	90.6 (3)	C2—C1—H1	118.8
O1ⁱ—Co1—N1ⁱ	85.4 (3)	C3—C2—C1	119.3 (10)
O1—Co1—N1ⁱ	92.1 (2)	C3—C2—H2	120.4
O1ⁱⁱ—Co1—N1ⁱ	175.1 (3)	C1—C2—H2	120.4
O1ⁱ—Co1—N1ⁱⁱ	92.1 (2)	C4—C3—C2	117.6 (10)
O1—Co1—N1ⁱⁱ	175.1 (3)	C4—C3—H3	121.2
O1ⁱⁱ—Co1—N1ⁱⁱ	85.4 (3)	C2—C3—H3	121.2
N1ⁱ—Co1—N1ⁱⁱ	92.1 (3)	C3—C4—C5	122.2 (11)
O1ⁱ—Co1—N1	175.1 (3)	C3—C4—H4	118.9
O1—Co1—N1	85.4 (3)	C5—C4—H4	118.9
O1ⁱⁱ—Co1—N1	92.1 (2)	N1—C5—C4	121.4 (11)
N1ⁱ—Co1—N1	92.1 (3)	N1—C5—C6	115.8 (10)
N1ⁱⁱ—Co1—N1	92.1 (3)	C4—C5—C6	122.5 (11)
C6—O1—Co1	113.3 (7)	O2—C6—O1	116.2 (13)
C1—N1—C5	117.1 (9)	O2—C6—C5	130.0 (13)
C1—N1—Co1	131.3 (7)	O1—C6—C5	113.8 (10)
C5—N1—Co1	111.5 (7)

O1ⁱ—Co1—O1—C6	179.0 (6)	C1—C2—C3—C4	−0.2 (14)
O1ⁱⁱ—Co1—O1—C6	88.4 (8)	C2—C3—C4—C5	1.2 (15)
N1—Co1—O1—C6	−3.7 (7)	C1—N1—C5—C4	1.3 (13)
O1—Co1—N1—C1	−175.4 (8)	Co1—N1—C5—C4	−177.9 (7)
O1ⁱⁱ—Co1—N1—C1	94.2 (9)	C1—N1—C5—C6	176.1 (7)
N1ⁱ—Co1—N1—C1	−83.4 (7)	Co1—N1—C5—C6	−3.1 (8)
N1ⁱⁱ—Co1—N1—C1	8.8 (8)	C3—C4—C5—N1	−1.8 (14)
O1—Co1—N1—C5	3.7 (6)	C3—C4—C5—C6	−176.3 (8)
O1ⁱⁱ—Co1—N1—C5	−86.7 (6)	Co1—O1—C6—O2	−177.8 (7)
N1ⁱ—Co1—N1—C5	95.7 (7)	Co1—O1—C6—C5	2.9 (9)
N1ⁱⁱ—Co1—N1—C5	−172.1 (6)	N1—C5—C6—O2	−179.0 (10)
C5—N1—C1—C2	−0.3 (13)	C4—C5—C6—O2	−4.2 (13)
Co1—N1—C1—C2	178.7 (6)	N1—C5—C6—O1	0.2 (9)
N1—C1—C2—C3	−0.2 (14)	C4—C5—C6—O1	174.9 (9)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O2ⁱⁱⁱ	0.95	2.60	3.212 (14)	123

Symmetry code: (iii) x−y+1, x, z−1.

Experimental details

Crystal data
Chemical formula	[Co(C₆H₄NO₂)₃]
M_r	425.24
Crystal system, space group	Hexagonal, P6
Temperature (K)	120
a, c (Å)	12.8617 (12), 6.2122 (9)
V (Å³)	890.0 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	1.01
Crystal size (mm)	0.23 × 0.08 × 0.03

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997)
T_min, T_max	0.800, 0.970
No. of measured, independent and observed [I > 2σ(I)] reflections	5635, 978, 893
R_int	0.043
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.068, 0.197, 1.16
No. of reflections	978
No. of parameters	86
No. of restraints	1
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.05, −0.59
Absolute structure	Flack (1983), 400 Friedel pairs
Absolute structure parameter	−0.02 (7)

Computer programs: COLLECT (Nonius, 1998), DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O2ⁱ	0.95	2.60	3.212 (14)	123

Symmetry code: (i) x−y+1, x, z−1.

Acknowledgements

Financial support from the State Fund for Fundamental Research of Ukraine (grant No. F40.3/041) and the Swedish Institute (Visby Program) is gratefully acknowledged.

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