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Acta Cryst. (2007). E63, m1815    [ doi:10.1107/S1600536807026761 ]

Bis(acetylacetonato-[kappa]2O,O')[2,2'-methylenebis(4,6-xylenolato)-[kappa]2O,O']titanium(IV)

M. S. Balakrishna, R. Panda and J. T. Mague

Abstract top

The title compound, [Ti(C5H7O2)2(C17H18O2)], was synthesized by the reaction of Ti(acac)2Cl2 (acac = acetylacetonate) with one equivalent of the diol {[HOC6H2(Me)2]([mu]-CH2)[(Me)2C6H2OH]} in the presence of sodium acetate. The coordination about the Ti atom is slightly distorted octahedral and the bisphenoxo ligand adopts an `open book' conformation.

Comment top

Titanium complexes containing aryloxides with bulky substituents are of interest in homogeneous catalysis, particularly in relation to polymerization processes (Priya et al., 2004; Fokken et al.,1996; Groysman et al., 2003). When bulky phenolate ligands are employed instead of metallocenes better results were obtained in polymerization of olefins (Hanava et al., 2003). The utility of titanium aryloxides in catalytic reactions such as olefin polymerization, oxidation, epoxidation and carbon-carbon coupling reactions are well documented (Chuck et al., 2006). Here, we report the mixed ligand complex [(–OC(CH3)CHC(CH3)O–)2Ti{(–OC6H2(Me)2)(µ-CH2) ((Me)2C6H2O–)}].

The coordination about the titanium(IV) center is distorted octahedral (Table 1). The acetylacetonate ligands are planar within 0.01 Å but are not coplanar with the metal. Instead, the O1, O2, C1, C2, C3 plane makes a dihedral angle of 16.1 (2)° with the Ti1 O1 O2 plane while the corresponding angle for the other acetylacetonate ligand is 14.0 (1)°. The bisphenoxo ligand adopts a open book conformation with the dihedral angle between the two aromatic rings being 106.79 (8)°. The two Ti—O—C angles associated with this ligand differ significantly (Table 1). This is attributed to packing considerations since the rings containing C20 through C26 in two adjacent molecules are parallel, partially interleaved and separated by 3.74 Å while C12 and C13 in the other ring make contacts, respectively, with H8 (2.88 Å) and H10B (2.89 Å) in the molecule at x,-1 + y,z. The former interaction tends to open up the Ti—O6—C20 angle while the latter acts to decrease the Ti—O5—C11 angle.

Related literature top

For related literature, see: Chuck et al. (2006); Fokken et al. (1996); Groysman et al. (2003); Hanava et al. (2003); Priya et al. (2004).

Experimental top

To a solution of Ti(acac)2Cl2 (0.225 g, 0.71 mmol) in CH3CN (15 ml), a mixture of diol (0.181 g, 0.71 mmol) and sodium acetate (0.116 g, 1.42 mmol) in the same solvent (15 ml) was added dropwise at 300 K and the mixture was refluxed for 8 h. The reaction mixture was cooled to room temperature and filtered through celite. The filtrate was concentrated to a small volume (3 ml) and hexane was added (2 ml). Storage of the solution at 263 K yielded dark red blocks of the title compound (0.237 g, 67%; m.p.: 419–421 K). Analysis, calculated for C27H32O6Ti: C 64.77, H 6.45; found: C 64.62, H 6.46%. Spectroscopic analysis: 1H NMR (300 MHz, 298 K, CDCl3, δ, p.p.m.): 7.12–7.26 (m, 4 H, phenyl), 5.95 (s, 1 H, CH, acac), 4.41 (s, 2 H, CH2), 2.08 (m, 6 H, CH3), 1.42 (s, 18 H, tert-butyl).

Refinement top

H atoms were placed in calculated positions (C—H = 0.95–0.98 Å) and included as riding contributions with isotropic displacement parameters 1.2–1.5 times those of the attached carbon atoms.

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures top
[Figure 1] Fig. 1. Perspective view of the title compound. Displacement ellipsoids are drawn at the 50% level and H-atoms are drawn as spheres of arbitrary radius.
Bis(acetylacetonato-κ2O,O')[2,2'-methylenebis(4,6-xylenolato)-κ2O,O'] titanium(IV) top
Crystal data top
[Ti(C5H7O2)2(C17H18O2)]Z = 2
Mr = 500.43F000 = 528
Triclinic, P1Dx = 1.272 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 8.3605 (9) ÅCell parameters from 25 reflections
b = 9.3419 (7) Åθ = 18.2–23.1º
c = 17.652 (1) ŵ = 0.37 mm−1
α = 92.472 (5)ºT = 298 (2) K
β = 95.599 (7)ºBlock, red
γ = 107.209 (7)º0.46 × 0.40 × 0.26 mm
V = 1306.9 (2) Å3
Data collection top
Enraf–Nonius CAD-4
diffractometer		Rint = 0.021
Radiation source: fine-focus sealed tubeθmax = 25.1º
Monochromator: graphiteθmin = 2.3º
T = 298(2) Kh = 0→9
θ/2θ scansk = −11→10
Absorption correction: empirical (using intensity measurements)
ψ scans (North et al., 1968)		l = −21→20
Tmin = 0.850, Tmax = 0.9112 standard reflections
4973 measured reflections every 2 min
4628 independent reflections intensity decay: <1%
3123 reflections with I > 2σ(I)
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H-atom parameters constrained
wR(F2) = 0.127  w = 1/[σ2(Fo2) + (0.063P)2 + 0.4456P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.001
4628 reflectionsΔρmax = 0.23 e Å−3
314 parametersΔρmin = −0.34 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[Ti(C5H7O2)2(C17H18O2)]γ = 107.209 (7)º
Mr = 500.43V = 1306.9 (2) Å3
Triclinic, P1Z = 2
a = 8.3605 (9) ÅMo Kα
b = 9.3419 (7) ŵ = 0.37 mm−1
c = 17.652 (1) ÅT = 298 (2) K
α = 92.472 (5)º0.46 × 0.40 × 0.26 mm
β = 95.599 (7)º
Data collection top
Enraf–Nonius CAD-4
diffractometer		3123 reflections with I > 2σ(I)
Absorption correction: empirical (using intensity measurements)
ψ scans (North et al., 1968)		Rint = 0.021
Tmin = 0.850, Tmax = 0.9112 standard reflections
4973 measured reflections every 2 min
4628 independent reflections intensity decay: <1%
Refinement top
R[F2 > 2σ(F2)] = 0.040314 parameters
wR(F2) = 0.127H-atom parameters constrained
S = 1.02Δρmax = 0.23 e Å−3
4628 reflectionsΔρmin = −0.34 e Å−3
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. H-atoms were placed in calculated positions (C—H = 0.95 − 0.98 Å) and included as riding contributions with isotropic displacement parameters 1.2 − 1.5 times those of the attached carbon atoms.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Ti10.83024 (6)0.95224 (5)0.68559 (3)0.04474 (16)
O10.7004 (3)0.8836 (2)0.57985 (11)0.0600 (5)
O21.0249 (2)0.9282 (2)0.63419 (10)0.0541 (5)
O30.8816 (2)1.1664 (2)0.65189 (10)0.0516 (5)
O40.6234 (2)0.9907 (2)0.71662 (11)0.0531 (5)
O50.7537 (2)0.7554 (2)0.70880 (10)0.0508 (5)
O60.9587 (2)1.02024 (19)0.77511 (10)0.0476 (4)
C10.7354 (5)0.8132 (4)0.52428 (17)0.0732 (10)
C20.5923 (6)0.7500 (6)0.4607 (2)0.1285 (19)
H2A0.51360.66180.47620.193*
H2B0.63670.72430.41560.193*
H2C0.53610.82410.44990.193*
C30.8900 (5)0.7935 (5)0.5200 (2)0.0895 (12)
H30.90250.73570.47800.107*
C41.0287 (4)0.8529 (4)0.57311 (17)0.0637 (8)
C51.1956 (5)0.8313 (5)0.5618 (2)0.0929 (13)
H5A1.28450.91370.58790.111*
H5B1.20760.82730.50830.111*
H5C1.20150.73900.58200.111*
C60.8209 (3)1.2722 (3)0.67020 (15)0.0481 (6)
C70.9100 (4)1.4253 (3)0.64689 (19)0.0692 (9)
H7A1.02171.46010.67360.083*
H7B0.84881.49370.65930.083*
H7C0.91641.42010.59290.083*
C80.6801 (3)1.2504 (3)0.70863 (16)0.0529 (7)
H80.64781.33420.72240.063*
C90.5848 (3)1.1124 (3)0.72778 (14)0.0477 (6)
C100.4241 (4)1.0942 (4)0.76311 (19)0.0669 (9)
H10A0.32941.05190.72510.080*
H10B0.42131.19060.78300.080*
H10C0.41911.02860.80380.080*
C110.7272 (3)0.6725 (3)0.77042 (14)0.0434 (6)
C120.5619 (3)0.5910 (3)0.78049 (16)0.0507 (7)
C130.5362 (4)0.5020 (3)0.84165 (17)0.0552 (7)
H130.42640.44850.84880.066*
C140.6676 (4)0.4898 (3)0.89250 (16)0.0499 (6)
C150.8289 (3)0.5727 (3)0.88113 (15)0.0466 (6)
H150.91860.56610.91490.056*
C160.8635 (3)0.6658 (3)0.82145 (14)0.0414 (6)
C170.4165 (4)0.6007 (4)0.7242 (2)0.0755 (10)
H17A0.31350.53070.73560.113*
H17B0.43680.57690.67330.113*
H17C0.40740.70080.72820.113*
C180.6375 (5)0.3883 (4)0.9572 (2)0.0732 (9)
H18A0.74360.38360.98140.088*
H18B0.56940.28930.93760.088*
H18C0.58040.42740.99380.088*
C191.0431 (3)0.7572 (3)0.81441 (15)0.0432 (6)
H19A1.05310.78110.76180.052*
H19B1.11770.69770.82780.052*
C201.0499 (3)1.0264 (3)0.84343 (13)0.0397 (5)
C211.0956 (3)1.1597 (3)0.89035 (15)0.0439 (6)
C221.1872 (3)1.1633 (3)0.96104 (15)0.0480 (6)
H221.21591.25060.99330.058*
C231.2369 (3)1.0433 (3)0.98512 (14)0.0470 (6)
C241.1904 (3)0.9132 (3)0.93643 (15)0.0448 (6)
H241.22270.83090.95190.054*
C251.0974 (3)0.9015 (3)0.86565 (14)0.0399 (5)
C261.0431 (4)1.2922 (3)0.86477 (19)0.0668 (9)
H26A1.08801.37520.90260.080*
H26B0.92231.26590.85820.080*
H26C1.08551.32020.81720.080*
C271.3356 (4)1.0516 (4)1.06257 (16)0.0612 (8)
H27A1.36201.15121.08670.073*
H27B1.43811.02821.05650.073*
H27C1.26930.98071.09370.073*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ti10.0526 (3)0.0502 (3)0.0340 (3)0.0202 (2)0.00336 (19)0.00056 (19)
O10.0672 (13)0.0742 (14)0.0399 (11)0.0279 (11)−0.0059 (9)0.0002 (10)
O20.0589 (12)0.0664 (12)0.0435 (11)0.0275 (10)0.0117 (9)0.0018 (9)
O30.0589 (12)0.0553 (11)0.0485 (11)0.0248 (9)0.0173 (9)0.0113 (9)
O40.0501 (11)0.0556 (11)0.0554 (12)0.0167 (9)0.0127 (9)0.0044 (9)
O50.0581 (11)0.0503 (11)0.0426 (10)0.0164 (9)−0.0002 (8)0.0008 (8)
O60.0576 (11)0.0481 (10)0.0382 (10)0.0195 (9)0.0016 (8)−0.0011 (8)
C10.097 (3)0.085 (2)0.0383 (17)0.036 (2)−0.0102 (16)−0.0087 (16)
C20.140 (4)0.160 (5)0.075 (3)0.055 (4)−0.043 (3)−0.050 (3)
C30.111 (3)0.123 (3)0.0485 (19)0.062 (3)0.0014 (19)−0.024 (2)
C40.083 (2)0.074 (2)0.0461 (17)0.0388 (18)0.0187 (16)0.0100 (15)
C50.102 (3)0.126 (3)0.075 (2)0.065 (3)0.031 (2)0.004 (2)
C60.0546 (16)0.0529 (16)0.0370 (14)0.0190 (13)−0.0016 (11)0.0021 (11)
C70.082 (2)0.0534 (18)0.072 (2)0.0177 (16)0.0174 (18)0.0075 (15)
C80.0530 (16)0.0559 (17)0.0537 (17)0.0238 (14)0.0055 (13)−0.0030 (13)
C90.0443 (15)0.0617 (17)0.0366 (14)0.0184 (13)−0.0010 (11)−0.0065 (12)
C100.0517 (18)0.082 (2)0.069 (2)0.0227 (16)0.0139 (15)−0.0076 (17)
C110.0513 (15)0.0360 (13)0.0438 (14)0.0165 (12)0.0031 (12)−0.0059 (11)
C120.0463 (15)0.0465 (15)0.0566 (17)0.0128 (12)0.0025 (12)−0.0093 (13)
C130.0477 (16)0.0434 (15)0.070 (2)0.0061 (12)0.0136 (14)−0.0020 (14)
C140.0574 (17)0.0361 (13)0.0533 (16)0.0089 (12)0.0107 (13)−0.0006 (12)
C150.0558 (16)0.0381 (13)0.0475 (15)0.0187 (12)0.0019 (12)−0.0026 (11)
C160.0461 (14)0.0336 (12)0.0456 (14)0.0146 (11)0.0073 (11)−0.0060 (10)
C170.0539 (19)0.081 (2)0.086 (3)0.0190 (17)−0.0121 (17)0.0027 (19)
C180.084 (2)0.0562 (18)0.077 (2)0.0113 (17)0.0199 (19)0.0170 (16)
C190.0445 (14)0.0425 (14)0.0461 (14)0.0189 (11)0.0053 (11)0.0003 (11)
C200.0351 (13)0.0477 (14)0.0355 (13)0.0114 (11)0.0056 (10)−0.0013 (11)
C210.0365 (13)0.0457 (14)0.0484 (15)0.0122 (11)0.0043 (11)−0.0039 (12)
C220.0387 (14)0.0526 (16)0.0483 (15)0.0096 (12)0.0030 (11)−0.0118 (12)
C230.0361 (13)0.0606 (17)0.0400 (14)0.0088 (12)0.0048 (11)−0.0011 (12)
C240.0378 (13)0.0491 (15)0.0480 (15)0.0127 (11)0.0056 (11)0.0090 (12)
C250.0342 (13)0.0448 (14)0.0414 (13)0.0112 (11)0.0100 (10)0.0027 (11)
C260.0651 (19)0.0509 (17)0.081 (2)0.0219 (15)−0.0137 (16)−0.0161 (16)
C270.0547 (18)0.075 (2)0.0468 (16)0.0123 (15)−0.0026 (13)0.0025 (15)
Geometric parameters (Å, °) top
Ti1—O61.798 (2)C11—C161.400 (4)
Ti1—O51.839 (2)C12—C131.386 (4)
Ti1—O41.989 (2)C12—C171.520 (4)
Ti1—O22.002 (2)C13—C141.385 (4)
Ti1—O12.040 (2)C13—H130.9300
Ti1—O32.046 (2)C14—C151.381 (4)
O1—C11.263 (4)C14—C181.508 (4)
O2—C41.270 (3)C15—C161.393 (4)
O3—C61.280 (3)C15—H150.9300
O4—C91.283 (3)C16—C191.512 (4)
O5—C111.360 (3)C17—H17A0.9600
O6—C201.352 (3)C17—H17B0.9600
C1—C31.367 (5)C17—H17C0.9600
C1—C21.518 (5)C18—H18A0.9600
C2—H2A0.9600C18—H18B0.9600
C2—H2B0.9600C18—H18C0.9600
C2—H2C0.9600C19—C251.515 (3)
C3—C41.376 (5)C19—H19A0.9700
C3—H30.9300C19—H19B0.9700
C4—C51.499 (5)C20—C211.396 (3)
C5—H5A0.9600C20—C251.398 (3)
C5—H5B0.9600C21—C221.392 (4)
C5—H5C0.9600C21—C261.504 (4)
C6—C81.383 (4)C22—C231.376 (4)
C6—C71.500 (4)C22—H220.9300
C7—H7A0.9600C23—C241.390 (4)
C7—H7B0.9600C23—C271.513 (4)
C7—H7C0.9600C24—C251.388 (3)
C8—C91.376 (4)C24—H240.9300
C8—H80.9300C26—H26A0.9600
C9—C101.503 (4)C26—H26B0.9600
C10—H10A0.9600C26—H26C0.9600
C10—H10B0.9600C27—H27A0.9600
C10—H10C0.9600C27—H27B0.9600
C11—C121.399 (4)C27—H27C0.9600
O6—Ti1—O595.80 (8)C12—C11—C16120.8 (2)
O6—Ti1—O496.15 (8)C13—C12—C11118.5 (3)
O5—Ti1—O490.98 (8)C13—C12—C17121.9 (3)
O6—Ti1—O292.84 (8)C11—C12—C17119.6 (3)
O5—Ti1—O295.41 (8)C14—C13—C12122.5 (3)
O4—Ti1—O2168.39 (8)C14—C13—H13118.7
O6—Ti1—O1175.50 (9)C12—C13—H13118.7
O5—Ti1—O187.13 (8)C15—C14—C13117.4 (3)
O4—Ti1—O187.20 (8)C15—C14—C18120.9 (3)
O2—Ti1—O183.46 (8)C13—C14—C18121.7 (3)
O6—Ti1—O390.75 (8)C14—C15—C16123.0 (3)
O5—Ti1—O3171.80 (8)C14—C15—H15118.5
O4—Ti1—O383.40 (8)C16—C15—H15118.5
O2—Ti1—O389.17 (8)C15—C16—C11117.7 (2)
O1—Ti1—O386.64 (8)C15—C16—C19119.9 (2)
C1—O1—Ti1129.8 (2)C11—C16—C19122.4 (2)
C4—O2—Ti1130.9 (2)C12—C17—H17A109.5
C6—O3—Ti1130.3 (2)C12—C17—H17B109.5
C9—O4—Ti1132.1 (2)H17A—C17—H17B109.5
C11—O5—Ti1140.2 (2)C12—C17—H17C109.5
C20—O6—Ti1162.5 (2)H17A—C17—H17C109.5
O1—C1—C3123.7 (3)H17B—C17—H17C109.5
O1—C1—C2115.3 (3)C14—C18—H18A109.5
C3—C1—C2121.1 (3)C14—C18—H18B109.5
C1—C2—H2A109.5H18A—C18—H18B109.5
C1—C2—H2B109.5C14—C18—H18C109.5
H2A—C2—H2B109.5H18A—C18—H18C109.5
C1—C2—H2C109.5H18B—C18—H18C109.5
H2A—C2—H2C109.5C16—C19—C25111.9 (2)
H2B—C2—H2C109.5C16—C19—H19A109.2
C1—C3—C4124.9 (3)C25—C19—H19A109.2
C1—C3—H3117.6C16—C19—H19B109.2
C4—C3—H3117.6C25—C19—H19B109.2
O2—C4—C3123.2 (3)H19A—C19—H19B107.9
O2—C4—C5115.7 (3)O6—C20—C21118.5 (2)
C3—C4—C5121.1 (3)O6—C20—C25120.1 (2)
C4—C5—H5A109.5C21—C20—C25121.4 (2)
C4—C5—H5B109.5C22—C21—C20117.8 (2)
H5A—C5—H5B109.5C22—C21—C26122.1 (2)
C4—C5—H5C109.5C20—C21—C26120.1 (2)
H5A—C5—H5C109.5C23—C22—C21122.8 (2)
H5B—C5—H5C109.5C23—C22—H22118.6
O3—C6—C8123.4 (3)C21—C22—H22118.6
O3—C6—C7116.4 (3)C22—C23—C24117.7 (2)
C8—C6—C7120.3 (3)C22—C23—C27121.1 (3)
C6—C7—H7A109.5C24—C23—C27121.2 (3)
C6—C7—H7B109.5C25—C24—C23122.4 (2)
H7A—C7—H7B109.5C25—C24—H24118.8
C6—C7—H7C109.5C23—C24—H24118.8
H7A—C7—H7C109.5C24—C25—C20118.0 (2)
H7B—C7—H7C109.5C24—C25—C19121.7 (2)
C9—C8—C6124.0 (3)C20—C25—C19120.3 (2)
C9—C8—H8118.0C21—C26—H26A109.5
C6—C8—H8118.0C21—C26—H26B109.5
O4—C9—C8123.6 (2)H26A—C26—H26B109.5
O4—C9—C10115.0 (3)C21—C26—H26C109.5
C8—C9—C10121.4 (3)H26A—C26—H26C109.5
C9—C10—H10A109.5H26B—C26—H26C109.5
C9—C10—H10B109.5C23—C27—H27A109.5
H10A—C10—H10B109.5C23—C27—H27B109.5
C9—C10—H10C109.5H27A—C27—H27B109.5
H10A—C10—H10C109.5C23—C27—H27C109.5
H10B—C10—H10C109.5H27A—C27—H27C109.5
O5—C11—C12118.7 (2)H27B—C27—H27C109.5
O5—C11—C16120.4 (2)
Table 1
Selected geometric parameters (Å, °) top
Ti1—O61.798 (2)Ti1—O22.002 (2)
Ti1—O51.839 (2)Ti1—O12.040 (2)
Ti1—O41.989 (2)Ti1—O32.046 (2)
O6—Ti1—O595.80 (8)O4—Ti1—O187.20 (8)
O6—Ti1—O496.15 (8)O2—Ti1—O183.46 (8)
O5—Ti1—O490.98 (8)O6—Ti1—O390.75 (8)
O6—Ti1—O292.84 (8)O5—Ti1—O3171.80 (8)
O5—Ti1—O295.41 (8)O4—Ti1—O383.40 (8)
O4—Ti1—O2168.39 (8)O2—Ti1—O389.17 (8)
O6—Ti1—O1175.50 (9)O1—Ti1—O386.64 (8)
O5—Ti1—O187.13 (8)
Acknowledgements top

The authors thank the Chemistry Department of Tulane University for support of the X-ray laboratory.

references
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