Bis(pyridine-κN)bis­[4,4,4-trifluoro-1-(4-fluoro­phen­yl)butane-1,3-dionato-κ2O,O′]cobalt(II)

Fan, L.; Wang, D.; Peng, L.; Ke, X.

doi:10.1107/S1600536807067955

metal-organic compounds

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Volume 64| Part 2| February 2008| Page m347

doi:10.1107/S1600536807067955

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Bis(pyridine-κN)bis[4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dionato-κ²O,O′]cobalt(II)

Ling Fan,^a Dunjia Wang,^a ^* Lihong Peng ^b and Xiaocui Ke ^b

^aHubei Key Laboratory of Bioanalytical Techniques, Department of Chemistry and Environmental Engineering, Hubei Normal University, Huangshi 435002, People's Republic of China, and ^bDepartment of Chemistry and Environmental Engineering, Hubei Normal University, Huangshi 435002, People's Republic of China
^*Correspondence e-mail: dunjiawang@163.com

(Received 1 November 2007; accepted 20 December 2007; online 16 January 2008)

In the structure of the title compound, [Co(C₁₀H₅F₄O₂)₂(C₅H₅N)₂], cobalt(II) forms a complex with two 4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dionate anions and two pyridine molecules in an octahedral coordination environment, where the two dionate ligands are in equatorial positions and the two pyridine molecules in axial positions. The complex is located on a crystallographic inversion centre.

Related literature

For related literature, see: Fan et al. (2007 ); Feng (2002 ); Lu et al. (2003 ); Sloopa et al. (2002 ).

Experimental

Crystal data

[Co(C₁₀H₅F₄O₂)₂(C₅H₅N)₂]
M_r = 683.41
Monoclinic, P 2₁ /c
a = 8.5181 (6) Å
b = 17.0379 (13) Å
c = 10.0150 (7) Å
β = 90.374 (2)°
V = 1453.45 (18) Å³
Z = 2
Mo Kα radiation
μ = 0.68 mm⁻¹
T = 293 (2) K
0.40 × 0.10 × 0.10 mm

Data collection

Bruker SMART 4K CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2001 ) T_min = 0.772, T_max = 0.935
16450 measured reflections
3299 independent reflections
2136 reflections with I > 2σ(I)
R_int = 0.063

Refinement

R[F² > 2σ(F²)] = 0.059
wR(F²) = 0.138
S = 1.09
3299 reflections
205 parameters
H-atom parameters constrained
Δρ_max = 0.44 e Å⁻³
Δρ_min = −0.29 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Co1—O1	2.055 (2)
Co1—O2	2.033 (2)
Co1—N1	2.195 (3)

O1—Co1—O2	88.35 (8)
O1—Co1—N1	93.58 (9)
O2—Co1—N1	90.24 (9)

Data collection: SMART (Bruker, 1997 ); cell refinement: SAINT (Bruker, 1999 ); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536807067955/kj2078sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536807067955/kj2078Isup2.hkl

checkCIF report

Comment top

The chelating group 1,3-diketone, widely used in coordination chemistry for a long time (Fan et al., 2007; Lu et al., 2003; Feng, 2002), has been increasingly encountered as a constituent of polydentate ligands in the context of metallo-supramolecular chemistry. In this paper, we report the crystal structure of the title compound, Co(C₁₀H₅O₂F₄)₂(C₅H₅N)₂. The Co(II) ion is located on a crystallographic inversion centre and is coordinated by two 4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dione oxygen atoms and two nitrogen atoms of pyridines, forming a distorted octahedron coordination geometry (Fig. 1). The chelate fragment is planar and the both lengths imply strong conjugation in chelate rings (Table 1).

Related literature top

For related literature, see: Fan et al. (2007); Feng (2002); Lu et al. (2003); Sloopa et al. (2002).

Experimental top

The ligand 4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dione was synthesized according to the reported literature (Sloopa et al., 2002). The coordination compound was prepared according to the following procedure: a mixture of ligand (0.328 g, 1.4 mmol) and pyridine (0.111 g, 1.4 mmol), dissolved in hot acetone (20 ml) was added slowly to a solution of Co(CH₃COO)₂ ˙4H₂O (0.174 g, 0.7 mmol) in water (10 ml). The mixture was stirred for 3 h. After filtration, the red solution was allowed to stand at room temperature. Brown block-shaped crystals suitable for X-ray analysis were obtained in several days. C, H and N content analyses were performed on a Perkin Elmer 2400 analytical instrument. Anal. Calcd. (%) for C₃₀H₂₀CoF₈N₂O₄: C, 52.72; H, 2.95; N, 4.10. Found (%): C, 53.01; H, 2.72; N, 4.20.

Computing details top

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Figures top

Fig. 1. View of the title compound, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 30% probability level. H-atoms are represented by circles of arbitrary size. Symmetry codes: a: (2 - x, 2 - y, 2 - z).

Bis(pyridine-κN)bis[4,4,4-trifluoro-1-(4-fluorophenyl)butane-1,3-dionato-\ κ²O,O']cobalt(II) top

Crystal data top

[Co(C₁₀H₅F₄O₂)₂(C₅H₅N)₂]	F(000) = 690
M_r = 683.41	D_x = 1.562 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P2ybc	Cell parameters from 1950 reflections
a = 8.5181 (6) Å	θ = 2.4–20.8°
b = 17.0379 (13) Å	µ = 0.68 mm⁻¹
c = 10.0150 (7) Å	T = 293 K
β = 90.374 (2)°	Block, brown
V = 1453.45 (18) Å³	0.40 × 0.10 × 0.10 mm
Z = 2

Data collection top

Bruker SMART 4K CCD area-detector diffractometer	3299 independent reflections
Radiation source: fine-focus sealed tube	2136 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.063
ϕ and ω scans	θ_max = 27.5°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	h = −11→11
T_min = 0.772, T_max = 0.935	k = −22→21
16450 measured reflections	l = −12→13

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)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.138	H-atom parameters constrained
S = 1.10	w = 1/[σ²(F_o²) + (0.059P)² + 0.1443P] where P = (F_o² + 2F_c²)/3
3299 reflections	(Δ/σ)_max < 0.001
205 parameters	Δρ_max = 0.44 e Å⁻³
0 restraints	Δρ_min = −0.29 e Å⁻³

Crystal data top

[Co(C₁₀H₅F₄O₂)₂(C₅H₅N)₂]	V = 1453.45 (18) Å³
M_r = 683.41	Z = 2
Monoclinic, P2₁/c	Mo Kα radiation
a = 8.5181 (6) Å	µ = 0.68 mm⁻¹
b = 17.0379 (13) Å	T = 293 K
c = 10.0150 (7) Å	0.40 × 0.10 × 0.10 mm
β = 90.374 (2)°

Data collection top

Bruker SMART 4K CCD area-detector diffractometer	3299 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	2136 reflections with I > 2σ(I)
T_min = 0.772, T_max = 0.935	R_int = 0.063
16450 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.059	0 restraints
wR(F²) = 0.138	H-atom parameters constrained
S = 1.10	Δρ_max = 0.44 e Å⁻³
3299 reflections	Δρ_min = −0.29 e Å⁻³
205 parameters

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
Co1	1.0000	1.0000	1.0000	0.0428 (2)
C1	1.1943 (3)	0.9984 (2)	0.6036 (3)	0.0479 (8)
C2	1.2093 (4)	0.9561 (3)	0.4859 (3)	0.0659 (10)
H2	1.1591	0.9079	0.4765	0.079*
C3	1.2988 (5)	0.9855 (3)	0.3824 (4)	0.0766 (12)
H3	1.3085	0.9574	0.3033	0.092*
C4	1.3713 (4)	1.0548 (3)	0.3971 (4)	0.0754 (12)
C5	1.3597 (4)	1.0991 (2)	0.5103 (4)	0.0732 (11)
H5	1.4099	1.1474	0.5178	0.088*
C6	1.2700 (4)	1.0691 (2)	0.6137 (3)	0.0599 (9)
H6	1.2611	1.0978	0.6922	0.072*
C7	1.0984 (3)	0.97134 (18)	0.7195 (3)	0.0432 (7)
C8	1.0258 (4)	0.89683 (18)	0.7204 (3)	0.0495 (8)
H8	1.0478	0.8627	0.6506	0.059*
C9	0.9242 (3)	0.87138 (17)	0.8183 (3)	0.0442 (7)
C10	0.8602 (4)	0.7887 (2)	0.8059 (3)	0.0568 (9)
C11	0.8337 (4)	1.1450 (2)	0.8834 (4)	0.0673 (10)
H11	0.9344	1.1531	0.8509	0.081*
C12	0.7186 (5)	1.1979 (2)	0.8505 (5)	0.0860 (13)
H12	0.7422	1.2414	0.7983	0.103*
C13	0.5687 (5)	1.1862 (3)	0.8949 (5)	0.0824 (12)
H13	0.4883	1.2206	0.8716	0.099*
C14	0.5405 (4)	1.1228 (3)	0.9741 (4)	0.0757 (11)
H14	0.4404	1.1136	1.0073	0.091*
C15	0.6617 (4)	1.0729 (2)	1.0041 (3)	0.0601 (9)
H15	0.6411	1.0299	1.0584	0.072*
F1	1.4601 (3)	1.08363 (17)	0.2953 (2)	0.1107 (9)
F3	0.8525 (3)	0.76125 (12)	0.6819 (2)	0.0869 (7)
F4	0.7189 (3)	0.78070 (13)	0.8566 (3)	0.1041 (9)
F5	0.9517 (3)	0.73792 (12)	0.8714 (2)	0.0910 (7)
N1	0.8080 (3)	1.08270 (15)	0.9594 (2)	0.0481 (6)
O1	0.8796 (2)	0.90574 (12)	0.9225 (2)	0.0506 (5)
O2	1.0882 (2)	1.01973 (12)	0.8149 (2)	0.0505 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Co1	0.0456 (3)	0.0427 (4)	0.0403 (3)	−0.0036 (3)	0.0131 (2)	−0.0079 (3)
C1	0.0444 (17)	0.062 (2)	0.0373 (17)	0.0143 (16)	0.0035 (13)	0.0043 (15)
C2	0.057 (2)	0.097 (3)	0.043 (2)	0.004 (2)	0.0051 (17)	−0.0090 (19)
C3	0.065 (2)	0.127 (4)	0.037 (2)	0.014 (2)	0.0073 (17)	−0.003 (2)
C4	0.059 (2)	0.115 (4)	0.053 (2)	0.023 (2)	0.0165 (19)	0.035 (2)
C5	0.077 (3)	0.073 (3)	0.070 (3)	0.011 (2)	0.026 (2)	0.022 (2)
C6	0.069 (2)	0.060 (2)	0.051 (2)	0.0100 (18)	0.0191 (17)	0.0066 (17)
C7	0.0398 (16)	0.0505 (18)	0.0393 (18)	0.0114 (14)	0.0037 (13)	−0.0001 (14)
C8	0.0566 (19)	0.0513 (19)	0.0408 (18)	0.0110 (15)	0.0085 (15)	−0.0100 (14)
C9	0.0413 (17)	0.0419 (17)	0.0494 (19)	0.0061 (14)	0.0017 (14)	−0.0087 (14)
C10	0.060 (2)	0.049 (2)	0.061 (2)	−0.0014 (17)	0.0095 (17)	−0.0132 (17)
C11	0.059 (2)	0.056 (2)	0.088 (3)	−0.0057 (18)	0.0111 (19)	0.011 (2)
C12	0.086 (3)	0.055 (2)	0.117 (4)	0.007 (2)	−0.001 (3)	0.019 (2)
C13	0.072 (3)	0.071 (3)	0.105 (3)	0.023 (2)	−0.005 (2)	−0.013 (3)
C14	0.051 (2)	0.091 (3)	0.084 (3)	0.016 (2)	0.0119 (19)	−0.013 (2)
C15	0.056 (2)	0.067 (2)	0.057 (2)	0.0000 (18)	0.0144 (17)	−0.0027 (18)
F1	0.0994 (17)	0.166 (3)	0.0678 (15)	0.0212 (17)	0.0392 (13)	0.0496 (15)
F3	0.1210 (19)	0.0674 (14)	0.0721 (15)	−0.0174 (13)	−0.0008 (13)	−0.0267 (11)
F4	0.0790 (16)	0.0701 (15)	0.164 (2)	−0.0272 (12)	0.0479 (16)	−0.0429 (15)
F5	0.1182 (19)	0.0515 (13)	0.1031 (19)	0.0003 (12)	−0.0169 (15)	0.0079 (12)
N1	0.0459 (15)	0.0505 (16)	0.0479 (15)	−0.0032 (12)	0.0095 (12)	−0.0060 (12)
O1	0.0502 (12)	0.0512 (13)	0.0506 (13)	−0.0053 (10)	0.0154 (10)	−0.0114 (10)
O2	0.0610 (13)	0.0467 (13)	0.0440 (13)	−0.0027 (10)	0.0178 (10)	−0.0046 (9)

Geometric parameters (Å, º) top

Co1—O1	2.055 (2)	C7—C8	1.412 (4)
Co1—O1ⁱ	2.055 (2)	C8—H8	0.9300
Co1—O2	2.033 (2)	C8—C9	1.382 (4)
Co1—O2ⁱ	2.033 (2)	C9—O1	1.257 (3)
Co1—N1ⁱ	2.195 (3)	C9—C10	1.516 (4)
Co1—N1	2.195 (3)	C10—F3	1.328 (4)
C1—C2	1.388 (4)	C10—F4	1.316 (4)
C1—C6	1.370 (4)	C10—F5	1.334 (4)
C1—C7	1.496 (4)	C11—N1	1.325 (4)
C2—H2	0.9300	C11—H11	0.9300
C2—C3	1.385 (5)	C11—C12	1.370 (5)
C3—H3	0.9300	C12—H12	0.9300
C3—C4	1.339 (6)	C12—C13	1.370 (5)
C4—F1	1.365 (4)	C13—H13	0.9300
C4—C5	1.366 (5)	C13—C14	1.362 (6)
C5—H5	0.9300	C14—H14	0.9300
C5—C6	1.389 (5)	C14—C15	1.370 (5)
C6—H6	0.9300	C15—N1	1.338 (4)
C7—O2	1.266 (3)	C15—H15	0.9300

O1—Co1—N1ⁱ	86.43 (9)	C9—C8—C7	124.3 (3)
O1ⁱ—Co1—N1ⁱ	93.58 (9)	C9—C8—H8	117.9
O1—Co1—O1ⁱ	180	C9—O1—Co1	121.66 (19)
O1—Co1—O2	88.35 (8)	C11—C12—H12	120.2
O1—Co1—N1	93.58 (9)	C11—N1—C15	116.7 (3)
O2ⁱ—Co1—O1	91.65 (8)	C11—N1—Co1	119.7 (2)
O2ⁱ—Co1—O1ⁱ	88.35 (8)	C12—C11—H11	118.5
O2—Co1—N1	90.24 (9)	C12—C13—H13	120.9
O2—Co1—N1ⁱ	89.76 (9)	C13—C12—C11	119.6 (4)
O2ⁱ—Co1—N1ⁱ	90.24 (9)	C13—C12—H12	120.2
O2—Co1—O2ⁱ	180	C13—C14—H14	120.5
N1ⁱ—Co1—N1	180	C13—C14—C15	119.0 (4)
C1—C2—H2	119.9	C14—C13—C12	118.2 (4)
C1—C6—C5	122.0 (3)	C14—C13—H13	120.9
C1—C6—H6	119.0	C14—C15—H15	118.3
C2—C1—C7	123.6 (3)	C15—C14—H14	120.5
C2—C3—H3	120.2	C15—N1—Co1	123.6 (2)
C3—C2—C1	120.1 (4)	O1—C9—C8	129.5 (3)
C3—C2—H2	119.9	O1—C9—C10	113.0 (3)
C3—C4—F1	119.5 (4)	O2—C7—C1	115.2 (3)
C3—C4—C5	122.9 (4)	O2—C7—C8	123.2 (3)
C4—C3—C2	119.5 (4)	F1—C4—C5	117.6 (4)
C4—C3—H3	120.3	F3—C10—C9	114.8 (3)
C4—C5—H5	121.4	F3—C10—F5	104.9 (3)
C4—C5—C6	117.2 (4)	F4—C10—F3	106.5 (3)
C5—C6—H6	119.0	F4—C10—F5	106.1 (3)
C6—C1—C2	118.2 (3)	F4—C10—C9	113.2 (3)
C6—C1—C7	118.2 (3)	F5—C10—C9	110.7 (3)
C6—C5—H5	121.4	N1—C11—H11	118.5
C7—C8—H8	117.9	N1—C11—C12	123.0 (4)
C7—O2—Co1	127.5 (2)	N1—C15—C14	123.5 (4)
C8—C7—C1	121.5 (3)	N1—C15—H15	118.3
C8—C9—C10	117.4 (3)

C6—C1—C2—C3	−0.1 (5)	C12—C13—C14—C15	−1.1 (6)
C7—C1—C2—C3	179.3 (3)	C13—C14—C15—N1	−0.1 (6)
C1—C2—C3—C4	0.4 (5)	C12—C11—N1—C15	0.1 (5)
C2—C3—C4—F1	179.7 (3)	C12—C11—N1—Co1	178.0 (3)
C2—C3—C4—C5	−0.9 (6)	C14—C15—N1—C11	0.7 (5)
C3—C4—C5—C6	1.0 (6)	C14—C15—N1—Co1	−177.2 (3)
F1—C4—C5—C6	−179.6 (3)	O2—Co1—N1—C11	−33.8 (3)
C2—C1—C6—C5	0.2 (5)	O2ⁱ—Co1—N1—C11	146.2 (3)
C7—C1—C6—C5	−179.1 (3)	O1—Co1—N1—C11	−122.2 (3)
C4—C5—C6—C1	−0.6 (5)	O1ⁱ—Co1—N1—C11	57.8 (3)
C6—C1—C7—O2	4.3 (4)	O2—Co1—N1—C15	144.0 (3)
C2—C1—C7—O2	−175.0 (3)	O2ⁱ—Co1—N1—C15	−36.0 (3)
C6—C1—C7—C8	−175.6 (3)	O1—Co1—N1—C15	55.6 (3)
C2—C1—C7—C8	5.1 (5)	O1ⁱ—Co1—N1—C15	−124.4 (3)
O2—C7—C8—C9	6.5 (5)	C8—C9—O1—Co1	−17.9 (4)
C1—C7—C8—C9	−173.6 (3)	C10—C9—O1—Co1	158.9 (2)
C7—C8—C9—O1	−1.7 (5)	O2—Co1—O1—C9	23.5 (2)
C7—C8—C9—C10	−178.3 (3)	O2ⁱ—Co1—O1—C9	−156.5 (2)
O1—C9—C10—F4	33.3 (4)	N1ⁱ—Co1—O1—C9	−66.3 (2)
C8—C9—C10—F4	−149.5 (3)	N1—Co1—O1—C9	113.7 (2)
O1—C9—C10—F3	155.9 (3)	C8—C7—O2—Co1	10.3 (4)
C8—C9—C10—F3	−26.9 (4)	C1—C7—O2—Co1	−169.56 (18)
O1—C9—C10—F5	−85.6 (3)	O1—Co1—O2—C7	−21.1 (2)
C8—C9—C10—F5	91.5 (3)	O1ⁱ—Co1—O2—C7	158.9 (2)
N1—C11—C12—C13	−1.3 (7)	N1ⁱ—Co1—O2—C7	65.4 (2)
C11—C12—C13—C14	1.8 (7)	N1—Co1—O2—C7	−114.6 (2)

Symmetry code: (i) −x+2, −y+2, −z+2.

Experimental details

Crystal data
Chemical formula	[Co(C₁₀H₅F₄O₂)₂(C₅H₅N)₂]
M_r	683.41
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	8.5181 (6), 17.0379 (13), 10.0150 (7)
β (°)	90.374 (2)
V (Å³)	1453.45 (18)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.68
Crystal size (mm)	0.40 × 0.10 × 0.10

Data collection
Diffractometer	Bruker SMART 4K CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2001)
T_min, T_max	0.772, 0.935
No. of measured, independent and observed [I > 2σ(I)] reflections	16450, 3299, 2136
R_int	0.063
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.059, 0.138, 1.10
No. of reflections	3299
No. of parameters	205
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.44, −0.29

Computer programs: SMART (Bruker, 1997), SAINT (Bruker, 1999), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Bruker, 2001).

Selected geometric parameters (Å, º) top

Co1—O1	2.055 (2)	C7—C8	1.412 (4)
Co1—O2	2.033 (2)	C8—C9	1.382 (4)
Co1—N1	2.195 (3)	C9—O1	1.257 (3)
C7—O2	1.266 (3)

O1—Co1—O2	88.35 (8)	O2—Co1—N1	90.24 (9)
O1—Co1—N1	93.58 (9)

Acknowledgements

The authors are grateful to Hubei Normal University and the Natural Science Foundation of the Educational Commission of Hubei Province (grant Nos. J200522002 and Z200622001) for financial support.

References

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