trans-Dimethanolbis(1,1,1-trifluoro-5,5-dimethylhexane-2,4-dionato)cobalt(II)

The Co atom of the title compound, [Co(C₈H₁₀F₃O₂)₂(CH₃OH)₂], which is located on a crystallographic inversion center, exhibits a distorted octa­hedral geometry. The bidentate acetyl­acetonate-like ligands are in a trans arrangement. The plane through the acetyl­acetonate unit is tilted with respect to the CoO₄ plane by 17.41 (7)°, which is in the same range as observed for similar Co(acac)₂OR₂ derivatives. Via the methanol hydr­oxy groups, each mol­ecule participates in two pairs of inter­molecular hydrogen bonds that create a network of hydrogen-bonded chains along the direction of the a axis.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.043
• wR factor = 0.114
• Data-to-parameter ratio = 17.7

checkCIF/PLATON results

No syntax errors found



Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.572     0.934
            Tmin(prime) and Tmax expected:      0.653     0.934
            RR(prime) =      0.876
            Please check that your absorption correction is appropriate.
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.96
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.87
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)        200 Deg.

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Co1         (2)       2.19
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   5 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

β-Diketones such as acetylacetonate (acac), and the metal complexes of their anions, have been used as in a variety of areas including catalysis in sol-gel synthesis (Mayo et al., 2000), carbon nanotube formation (Katok et al., 2006) and also as precursors for metal organic chemical vapor deposition (MOCVD) (Bessergenev, 2004). The synthesis of metal-β-diketonates has also been studied thoroughly (Skopenko et al., 2004). We are especially interested in fluorinated metal-β-diketonates, which, due to their increased volatility, are ideally suited as precursors for vapor deposition processes (Fahlmen, 2006) and allow for the detailed study of gas phase metal and ligand association reactions by mass spectrometry (Majer & Perry, 1969; Schildcrout, 1976). Varying the substituent identity and degree of fluorination are some of the routes used to tune the properties of MOCVD precursors and are currently under investigation in the gas phase. In the course of these studies the title compound was prepared by reaction of 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione (tftm) with CoCl₂ in a basic aqueous medium and subsequent recrystallization from methanol.

The β-diketonate ligand, as well as the methanol substituents in this crystal structure, are arranged in a trans geometry with the cobalt atom being localized on a crystallographic inversion center (Fig. 1). The CoO₄ plane, formed by the oxygen atoms of the chelating ligands and the Co atom, is planar. The Co—O bond distances and angles are within the expected range, with the tftm bite angle being the smallest at 89.82 (5)° and Co—O bonds ranging between 2.0338 (14) and 2.0388 (13) Å. The tftm ligands themselves are also nearly planar with an r.m.s. deviation from the mean plane formed by the two oxygen and five carbon atoms of the two ligands of only 0.0729. With respect to the CoO₄ plane however, the tftm ligands are tilted by 17.41 (7)° which compares well to values found for other similar Co compounds such as Co(acac)₂(H₂O)₂ and Co(acac)₂(MeOH)₂, with angles of 16.70° and 9.71° respectively (Bullen, 1959; Werndrup & Kessler, 2001).

The hydroxyl groups of the methanol ligands are involved in O—H···O hydrogen bonds towards O1ⁱ of a tftm ligand in a neighboring molecule (symmetry operator i: x - 1, y, z). Each molecule functions as both H donor and acceptor towards each two neighboring molecules. Chains of H-bound molecules extend along the a axis due to this network of H-bonds (Fig. 2)·Also, each two of the O—H···O bonds are related to each other by an inversion center located between two neighboring molecules, resulting in an R²₂(8) graph set motif (Bernstein et al., 1995).

Related literature

For information regarding the synthesis of various metal-β-diketonates see Skopenko et al. (2004) and Watson & Lin (1966). For similar metal–acetylacetonates refer to Bullen (1959) and Werndrup & Kessler (2001). Varying uses of metal-β-diketonates can be found in Mayo et al. (2000), Katok et al. (2006), Bessergenev (2004) and Fahlmen (2006). The paper by Bernstein et al. (1995) describes graph-set motifs. For related mass spectrometry work see Majer & Perry (1969) and Schildcrout (1976).

S2. Experimental

The synthesis of the title compound was adapted from Watson & Lin (1966). 0.2 ml (1.2 mmol) of the β-diketonate ligand was added to a solution of 0.11 g CoCl₂·6H₂O (0.5 mmol) in 100 ml de-ionized water. Diluted 1:1 (v/v) NH₄OH was added dropwise to the solution until no additional precipitate formed. The solution was stirred for 2 h and the precipitate was isolated by filtration. The desired product was separated from any impurities by extraction with toluene and filtration. Toluene was removed in vacuo and the product was subsequently re-crystallized from methanol.

S3. Refinement

The hydroxyl H atom was located in a difference density Fourier map. The O—H distance was restrained to 0.84 (2) Å. The other H atoms were placed in calculated positions with C—H distances of 0.980 (methyl) and 0.950 Å (CH). The methyl and hydroxyl H's were refined with an isotropic displacement parameter U_iso of 1.5 times U_eq of the adjacent carbon or oxygen atom, and the C—H hydrogen atom with U_iso = 1.2 U_eq(C). Methyl hydrogen atoms were allowed to rotate to best fit the experimental electron density.

Computing details

Data collection: SMART (Bruker, 2003); cell refinement: SAINT-Plus (Bruker, 2003); data reduction: SAINT-Plus (Bruker, 2003); program(s) used to solve structure: SHELXTL (Bruker, 2003); program(s) used to refine structure: SHELXTL (Bruker, 2003); molecular graphics: SHELXTL (Bruker, 2003); software used to prepare material for publication: SHELXTL (Bruker, 2003).

Figures

	Fig. 1. ORTEP representation of the title compound, with anisotropic displacement parameters for the non-H atoms of 50% probability.
	Fig. 2. Packing diagram showing the H-bonding network down the b axis at 50% probability.

trans-Dimethanolbis(1,1,1-trifluoro-5,5-dimethylhexane-2,4-dionato)cobalt(II)

Crystal data

[Co(C8H10F3O2)2(CH4O)2]	Z = 1
Mr = 513.33	F(000) = 265
Triclinic, P1	Dx = 1.546 Mg m^−3
a = 5.4390 (7) Å	Mo Kα radiation, λ = 0.71073 Å
b = 8.7181 (11) Å	Cell parameters from 3517 reflections
c = 12.0169 (15) Å	θ = 2.4–30.4°
α = 78.835 (2)°	µ = 0.86 mm^−1
β = 80.571 (2)°	T = 100 K
γ = 87.946 (2)°	Plate, red
V = 551.47 (12) Å^3	0.49 × 0.23 × 0.08 mm

Data collection

Bruker SMART APEX CCD diffractometer	2637 independent reflections
Radiation source: fine-focus sealed tube	2380 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
ω scans	θmax = 28.3°, θmin = 1.8°
Absorption correction: multi-scan (SADABS in SAINT-Plus; Bruker, 2003)	h = −7→7
Tmin = 0.572, Tmax = 0.934	k = −11→11
4542 measured reflections	l = −15→15

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.114	H atoms treated by a mixture of independent and constrained refinement
S = 1.07	w = 1/[σ^2(Fo^2) + (0.0734P)^2 + 0.1036P] where P = (Fo^2 + 2Fc^2)/3
2637 reflections	(Δ/σ)max < 0.001
149 parameters	Δρmax = 0.89 e Å^−3
1 restraint	Δρmin = −0.79 e Å^−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	0.6715 (4)	1.2223 (2)	0.26390 (17)	0.0224 (4)
C2	0.5746 (3)	1.0953 (2)	0.21029 (16)	0.0187 (4)
C3	0.4063 (4)	0.9910 (2)	0.27916 (17)	0.0209 (4)
H3	0.3564	1.0027	0.3566	0.025*
C4	0.3002 (3)	0.8652 (2)	0.24211 (17)	0.0190 (4)
C5	0.1482 (3)	0.7401 (2)	0.33239 (17)	0.0198 (4)
C6	−0.0258 (4)	0.8130 (2)	0.42237 (18)	0.0246 (4)
H6A	−0.1322	0.8919	0.3836	0.037*
H6B	0.0738	0.8624	0.4666	0.037*
H6C	−0.1302	0.7313	0.4744	0.037*
C7	−0.0022 (4)	0.6457 (3)	0.27254 (19)	0.0277 (4)
H7A	0.1114	0.5960	0.2178	0.042*
H7B	−0.1169	0.7155	0.2314	0.042*
H7C	−0.0977	0.5652	0.3300	0.042*
C8	0.3351 (4)	0.6316 (2)	0.39236 (19)	0.0255 (4)
H8A	0.2446	0.5499	0.4508	0.038*
H8B	0.4352	0.6923	0.4290	0.038*
H8C	0.4449	0.5832	0.3355	0.038*
C9	0.2186 (4)	1.3202 (2)	0.0062 (2)	0.0283 (4)
H9A	0.2177	1.3465	0.0820	0.042*
H9B	0.0805	1.3743	−0.0284	0.042*
H9C	0.3768	1.3530	−0.0433	0.042*
Co1	0.5000	1.0000	0.0000	0.01756 (13)
F1	0.9170 (2)	1.20843 (16)	0.26299 (12)	0.0330 (3)
F2	0.6323 (3)	1.36435 (15)	0.20402 (13)	0.0374 (3)
F3	0.5676 (3)	1.22055 (17)	0.37246 (12)	0.0377 (4)
O1	0.6700 (2)	1.10554 (15)	0.10421 (12)	0.0201 (3)
O2	0.3314 (3)	0.84840 (16)	0.13993 (12)	0.0208 (3)
O3	0.1904 (3)	1.15484 (17)	0.01845 (13)	0.0244 (3)
H3A	0.042 (4)	1.134 (3)	0.049 (2)	0.037*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0234 (9)	0.0219 (9)	0.0237 (10)	−0.0037 (7)	−0.0007 (7)	−0.0108 (8)
C2	0.0193 (9)	0.0174 (9)	0.0216 (9)	−0.0001 (7)	−0.0033 (7)	−0.0091 (7)
C3	0.0212 (9)	0.0228 (9)	0.0202 (9)	−0.0023 (7)	−0.0007 (7)	−0.0094 (7)
C4	0.0170 (8)	0.0184 (9)	0.0222 (9)	0.0001 (7)	−0.0012 (7)	−0.0073 (7)
C5	0.0188 (9)	0.0193 (9)	0.0222 (9)	−0.0032 (7)	0.0003 (7)	−0.0083 (7)
C6	0.0220 (9)	0.0249 (10)	0.0253 (10)	−0.0023 (8)	0.0040 (8)	−0.0064 (8)
C7	0.0262 (10)	0.0320 (11)	0.0258 (10)	−0.0128 (8)	−0.0009 (8)	−0.0082 (8)
C8	0.0242 (10)	0.0216 (10)	0.0293 (11)	−0.0016 (8)	−0.0014 (8)	−0.0039 (8)
C9	0.0318 (11)	0.0192 (10)	0.0339 (11)	0.0005 (8)	−0.0016 (9)	−0.0087 (8)
Co1	0.0185 (2)	0.0168 (2)	0.0188 (2)	−0.00344 (13)	−0.00057 (13)	−0.00835 (14)
F1	0.0239 (6)	0.0389 (7)	0.0430 (8)	−0.0064 (5)	−0.0069 (5)	−0.0221 (6)
F2	0.0544 (9)	0.0184 (6)	0.0456 (8)	−0.0014 (6)	−0.0175 (7)	−0.0132 (6)
F3	0.0436 (8)	0.0443 (8)	0.0287 (7)	−0.0183 (6)	0.0080 (6)	−0.0242 (6)
O1	0.0195 (6)	0.0202 (7)	0.0223 (7)	−0.0038 (5)	−0.0002 (5)	−0.0101 (5)
O2	0.0228 (7)	0.0193 (7)	0.0214 (7)	−0.0041 (5)	0.0003 (5)	−0.0091 (5)
O3	0.0197 (7)	0.0202 (7)	0.0340 (8)	−0.0015 (5)	−0.0003 (6)	−0.0104 (6)

Geometric parameters (Å, º)

C1—F3	1.332 (2)	C7—H7B	0.9800
C1—F1	1.335 (2)	C7—H7C	0.9800
C1—F2	1.336 (2)	C8—H8A	0.9800
C1—C2	1.532 (3)	C8—H8B	0.9800
C2—O1	1.282 (2)	C8—H8C	0.9800
C2—C3	1.368 (3)	C9—O3	1.432 (2)
C3—C4	1.432 (3)	C9—H9A	0.9800
C3—H3	0.9500	C9—H9B	0.9800
C4—O2	1.248 (2)	C9—H9C	0.9800
C4—C5	1.537 (3)	Co1—O2	2.0338 (14)
C5—C7	1.528 (3)	Co1—O2^i	2.0339 (14)
C5—C8	1.535 (3)	Co1—O1^i	2.0388 (13)
C5—C6	1.535 (3)	Co1—O1	2.0388 (13)
C6—H6A	0.9800	Co1—O3	2.1301 (15)
C6—H6B	0.9800	Co1—O3^i	2.1302 (15)
C6—H6C	0.9800	O3—H3A	0.840 (17)
C7—H7A	0.9800
F3—C1—F1	106.65 (17)	C5—C8—H8A	109.5
F3—C1—F2	107.19 (17)	C5—C8—H8B	109.5
F1—C1—F2	106.60 (16)	H8A—C8—H8B	109.5
F3—C1—C2	114.14 (16)	C5—C8—H8C	109.5
F1—C1—C2	111.10 (16)	H8A—C8—H8C	109.5
F2—C1—C2	110.78 (16)	H8B—C8—H8C	109.5
O1—C2—C3	130.15 (17)	O3—C9—H9A	109.5
O1—C2—C1	112.25 (16)	O3—C9—H9B	109.5
C3—C2—C1	117.60 (17)	H9A—C9—H9B	109.5
C2—C3—C4	124.26 (18)	O3—C9—H9C	109.5
C2—C3—H3	117.9	H9A—C9—H9C	109.5
C4—C3—H3	117.9	H9B—C9—H9C	109.5
O2—C4—C3	123.37 (17)	O2—Co1—O2^i	180.00 (6)
O2—C4—C5	117.62 (16)	O2—Co1—O1^i	90.18 (5)
C3—C4—C5	118.97 (17)	O2^i—Co1—O1^i	89.82 (5)
C7—C5—C8	109.26 (17)	O2—Co1—O1	89.82 (5)
C7—C5—C6	110.21 (16)	O2^i—Co1—O1	90.18 (5)
C8—C5—C6	109.09 (17)	O1^i—Co1—O1	180.00 (6)
C7—C5—C4	109.43 (16)	O2—Co1—O3	89.28 (6)
C8—C5—C4	107.12 (15)	O2^i—Co1—O3	90.72 (6)
C6—C5—C4	111.66 (15)	O1^i—Co1—O3	90.09 (6)
C5—C6—H6A	109.5	O1—Co1—O3	89.91 (6)
C5—C6—H6B	109.5	O2—Co1—O3^i	90.72 (6)
H6A—C6—H6B	109.5	O2^i—Co1—O3^i	89.28 (6)
C5—C6—H6C	109.5	O1^i—Co1—O3^i	89.91 (6)
H6A—C6—H6C	109.5	O1—Co1—O3^i	90.09 (6)
H6B—C6—H6C	109.5	O3—Co1—O3^i	179.999 (1)
C5—C7—H7A	109.5	C2—O1—Co1	119.97 (12)
C5—C7—H7B	109.5	C4—O2—Co1	127.11 (13)
H7A—C7—H7B	109.5	C9—O3—Co1	122.65 (12)
C5—C7—H7C	109.5	C9—O3—H3A	107 (2)
H7A—C7—H7C	109.5	Co1—O3—H3A	129 (2)
H7B—C7—H7C	109.5
F3—C1—C2—O1	176.81 (17)	C3—C2—O1—Co1	19.4 (3)
F1—C1—C2—O1	−62.6 (2)	C1—C2—O1—Co1	−160.77 (12)
F2—C1—C2—O1	55.7 (2)	O2—Co1—O1—C2	−23.55 (14)
F3—C1—C2—C3	−3.3 (3)	O2^i—Co1—O1—C2	156.45 (14)
F1—C1—C2—C3	117.3 (2)	O3—Co1—O1—C2	65.73 (14)
F2—C1—C2—C3	−124.4 (2)	O3^i—Co1—O1—C2	−114.27 (14)
O1—C2—C3—C4	0.3 (3)	C3—C4—O2—Co1	−7.2 (3)
C1—C2—C3—C4	−179.48 (18)	C5—C4—O2—Co1	175.20 (12)
C2—C3—C4—O2	−7.8 (3)	O1^i—Co1—O2—C4	−160.79 (16)
C2—C3—C4—C5	169.72 (18)	O1—Co1—O2—C4	19.21 (16)
O2—C4—C5—C7	−17.5 (2)	O3—Co1—O2—C4	−70.70 (16)
C3—C4—C5—C7	164.78 (18)	O3^i—Co1—O2—C4	109.30 (16)
O2—C4—C5—C8	100.8 (2)	O2—Co1—O3—C9	137.10 (16)
C3—C4—C5—C8	−76.9 (2)	O2^i—Co1—O3—C9	−42.90 (16)
O2—C4—C5—C6	−139.84 (19)	O1^i—Co1—O3—C9	−132.72 (16)
C3—C4—C5—C6	42.5 (2)	O1—Co1—O3—C9	47.28 (16)

Symmetry code: (i) −x+1, −y+2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O1^ii	0.84 (2)	2.03 (2)	2.867 (2)	172 (3)

Symmetry code: (ii) x−1, y, z.