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Acta Cryst. (2007). E63, m2563    [ doi:10.1107/S1600536807044832 ]

[mu]-Oxido-bis[dichlorido(diethylamido-[kappa]N)(diethylamine-[kappa]N)titanium(IV)]

N. A. Straessler, M. T. Caudle and T. L. Groy

Abstract top

In the title compound, [Ti2(C4H10N)2Cl4O(C4H11N)2], the bridging O atom resides on an inversion center, resulting in a 180° Ti-O-Ti bond angle.

Comment top

The structure of I was determined as part of an investigation into the effects of water on the synthesis of Ti(IV) complexes derived from secondary amines. Because the two titanium atoms in I are related by an inversion center on the bridging oxygen atom, the Ti—O—Ti bond angle is 180° indicating complete sp hybridization of the oxygen atom. This arises from dπpπ bonding through overlap of the px and py orbitals on oxygen with titanium dxy and dyz orbitals. Perfectly linear Ti—O—Ti complexes with oxygen as an inversion center have been reported (Krug & Müller, 1990; Thewalt & Schomburg, 1977). However, µ-oxo homodinuclear titanium species with Ti—O—Ti bond angles slightly less than 180° appear to be more common. (Honzíček et al., 2004; Levason et al., 2003; Mahrwald et al., 2001; Schormann, 2003)

In addition to the bridging oxygen in I, there is one diethylamido (N2) and one diethylamino (N1) group, as well as two chlorides (Cl1 and Cl2) coordinated to the titanium. Each titanium atom is best viewed as having distorted square pyramidal coordination geometry as judged by the τ-descriptor (Addison et al., 1984) which is 0.13 for this molecule. The amido group occupies the axial position, and Cl1, Cl2, N1 and O1 create the equatorial pseudo-square base. One chloride (Cl2) is trans to the bridging oxygen and the other chloride (Cl1) is trans to the amino group.

The diethylamido N atoms are nearly planar (N2 deviates from the Ti–C21–C23 plane by 0.077 (6) Å) as a result of strong pi interactions with the d0 Ti4+. Three of the four bond angles making up the base of the square pyramid in I are smaller than the ideal 90° (O1—Ti1—N1 = 82.49 (10)°, N1—Ti1—Cl2 = 83.20 (11)°, Cl2—Ti1—Cl1 = 89.73 (7)°). The four bond angles from the respective equatorial positions to the axial nitrogen are all larger than the ideal 90° and range from 102.09 (17)° to 108.65 (11)°. Deviation from ideal square pyramidal geometry can be attributed to electrostatic repulsions, particularly from the diethylamido nitrogen, and significant steric crowding around the Ti4+ centers.

Related literature top

For related literature, see: Addison et al. (1984); Honzíček et al. (2004); Krug & Müller (1990); Levason et al. (2003); Mahrwald et al. (2001); Schormann (2003); Thewalt & Schomburg (1977).

Experimental top

While stirring under a nitrogen atmosphere, 2 ml (18.24 mmol) of TiCl4 were added to approximately 60 ml of n-hexane in a Schlenk flask. Next, 0.16 ml (8.90 mmol) of distilled water mixed with 7.54 ml (72.90 mmol) of diethylamine was added dropwise to the solution. After 16 h of stirring, solid white diethylammonium chloride was removed by no-air filtration. The orange filtrate was evaporated to a minimal volume over a period of two days with a slow stream of nitrogen yielding X-ray quality crystals of I.

Refinement top

Hydrogen atoms were positioned geometrically and allowed to ride on their bonding partners with C—H distances = 0.96 Å and Uiso(H) = 1.5Ueq(C) for the methyl H atoms, C—H distances = 0.97 Å and Uiso(H) = 1.2Ueq(C) for the methylene H atoms, and N—H distance = 0.91 Å and Uiso(H) = 1.2Ueq(N) for the amino hydrogen.

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 2003b); software used to prepare material for publication: SHELXTL (Sheldrick, 2003b).

Figures top
[Figure 1] Fig. 1. Thermal ellipsoid plot of I shown at the 30% probability level. Hydrogen atoms have been omitted for clarity. Square pyramidal coordination geometry around the titanium atoms shown inset. [Symmetry operation (i): −x + 1/2, −y + 1/2, −z + 1/2].
µ-Oxo-bis[dichlorido(diethylamido-κN)(diethylamine-κN)titanium(IV)] top
Crystal data top
[Ti2(C4H10N)2Cl4O(C4H11N)2]F000 = 1144
Mr = 544.14Dx = 1.319 Mg m−3
Monoclinic, I2/aMo Kα radiation
λ = 0.71073 Å
Hall symbol: -I 2yaCell parameters from 3400 reflections
a = 13.204 (3) Åθ = 4.5–49.2º
b = 10.131 (2) ŵ = 0.99 mm−1
c = 20.795 (5) ÅT = 298 (2) K
β = 99.973 (3)ºBlock, orange
V = 2739.7 (10) Å30.40 × 0.35 × 0.20 mm
Z = 4
Data collection top
Bruker SMART APEX
diffractometer		2421 independent reflections
Radiation source: fine-focus sealed tube1446 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.093
T = 298(2) Kθmax = 25.0º
ω scansθmin = 2.0º
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003a)		h = −15→15
Tmin = 0.693, Tmax = 0.827k = −12→12
10591 measured reflectionsl = −24→24
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)] = 0.058H-atom parameters constrained
wR(F2) = 0.153  w = 1/[σ2(Fo2) + (0.0883P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.93(Δ/σ)max = 0.004
2421 reflectionsΔρmax = 0.45 e Å−3
128 parametersΔρmin = −0.29 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
[Ti2(C4H10N)2Cl4O(C4H11N)2]V = 2739.7 (10) Å3
Mr = 544.14Z = 4
Monoclinic, I2/aMo Kα
a = 13.204 (3) ŵ = 0.99 mm−1
b = 10.131 (2) ÅT = 298 (2) K
c = 20.795 (5) Å0.40 × 0.35 × 0.20 mm
β = 99.973 (3)º
Data collection top
Bruker SMART APEX
diffractometer		2421 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2003a)		1446 reflections with I > 2σ(I)
Tmin = 0.693, Tmax = 0.827Rint = 0.093
10591 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.058128 parameters
wR(F2) = 0.153H-atom parameters constrained
S = 0.93Δρmax = 0.45 e Å−3
2421 reflectionsΔρmin = −0.29 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Ti10.21205 (5)0.21280 (9)0.32732 (4)0.0574 (3)
Cl10.12134 (10)0.02633 (18)0.28158 (7)0.0953 (6)
Cl20.09047 (11)0.24341 (17)0.39498 (9)0.1030 (6)
O10.25000.25000.25000.0595 (11)
N10.2372 (3)0.4269 (4)0.34308 (18)0.0729 (12)
H1A0.28790.44790.32020.087*
C110.1437 (4)0.4984 (6)0.3087 (3)0.0835 (16)
H11A0.11420.44680.27070.100*
H11B0.09350.50040.33770.100*
C120.1579 (6)0.6342 (7)0.2870 (4)0.128 (3)
H12A0.19320.68500.32300.192*
H12B0.09200.67320.27130.192*
H12C0.19780.63300.25260.192*
C130.2737 (5)0.4784 (10)0.4096 (3)0.144 (3)
H13A0.23160.55440.41550.173*
H13B0.25930.41150.44010.173*
N20.3284 (2)0.1426 (4)0.37576 (16)0.0595 (10)
C210.3131 (4)0.0542 (6)0.4290 (2)0.0805 (17)
H21A0.24330.06460.43690.097*
H21B0.35920.08060.46840.097*
C220.3315 (5)−0.0908 (7)0.4159 (3)0.111 (2)
H22A0.2891−0.11680.37570.166*
H22B0.3145−0.14330.45100.166*
H22C0.4025−0.10390.41290.166*
C230.4344 (3)0.1478 (7)0.3616 (2)0.0812 (16)
H23A0.43770.21510.32890.097*
H23B0.45050.06370.34350.097*
C240.5138 (4)0.1774 (8)0.4206 (3)0.116 (2)
H24A0.49750.25940.43950.175*
H24B0.58020.18390.40800.175*
H24C0.51460.10770.45200.175*
C140.3706 (6)0.5140 (10)0.4276 (4)0.163 (4)
H14A0.41430.45260.41030.244*
H14B0.38760.51450.47440.244*
H14C0.38040.60080.41120.244*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Ti10.0338 (4)0.0910 (7)0.0502 (5)0.0052 (4)0.0148 (3)0.0161 (4)
Cl10.0633 (8)0.1336 (14)0.0909 (10)−0.0350 (8)0.0190 (7)0.0076 (9)
Cl20.0806 (10)0.1190 (13)0.1287 (12)0.0258 (8)0.0724 (9)0.0354 (10)
O10.054 (2)0.078 (3)0.048 (2)0.004 (2)0.0136 (19)0.009 (2)
N10.052 (2)0.111 (4)0.059 (2)−0.017 (2)0.0183 (18)−0.014 (2)
C110.072 (4)0.083 (4)0.094 (4)−0.006 (3)0.009 (3)0.001 (3)
C120.137 (6)0.090 (6)0.169 (7)0.000 (5)0.060 (5)0.008 (5)
C130.084 (4)0.261 (10)0.092 (5)−0.041 (6)0.023 (4)−0.076 (6)
N20.0385 (18)0.096 (3)0.045 (2)0.0096 (19)0.0109 (15)0.0081 (19)
C210.064 (3)0.116 (5)0.061 (3)0.015 (3)0.010 (2)0.020 (3)
C220.102 (5)0.101 (5)0.123 (5)0.019 (4)0.002 (4)0.022 (4)
C230.038 (2)0.143 (5)0.064 (3)0.009 (3)0.011 (2)0.001 (3)
C240.051 (3)0.188 (8)0.105 (5)−0.003 (4)−0.002 (3)0.001 (5)
C140.127 (7)0.205 (10)0.140 (7)−0.053 (7)−0.024 (6)−0.050 (6)
Geometric parameters (Å, °) top
Ti1—O11.8048 (8)N2—C211.465 (6)
Ti1—N21.828 (3)N2—C231.480 (5)
Ti1—N12.210 (5)C21—C221.521 (8)
Ti1—Cl22.3314 (14)C21—H21A0.9700
Ti1—Cl12.3480 (18)C21—H21B0.9700
O1—Ti1i1.8049 (8)C22—H22A0.9600
N1—C131.479 (7)C22—H22B0.9600
N1—C111.502 (6)C22—H22C0.9600
N1—H1A0.9100C23—C241.499 (7)
C11—C121.470 (9)C23—H23A0.9700
C11—H11A0.9700C23—H23B0.9700
C11—H11B0.9700C24—H24A0.9600
C12—H12A0.9600C24—H24B0.9600
C12—H12B0.9600C24—H24C0.9600
C12—H12C0.9600C14—H14A0.9600
C13—C141.320 (9)C14—H14B0.9600
C13—H13A0.9700C14—H14C0.9600
C13—H13B0.9700
O1—Ti1—N2103.63 (10)H13A—C13—H13B106.9
O1—Ti1—N182.49 (10)C21—N2—C23115.5 (4)
N2—Ti1—N1102.09 (17)C21—N2—Ti1116.2 (3)
O1—Ti1—Cl2146.75 (6)C23—N2—Ti1127.6 (3)
N2—Ti1—Cl2108.65 (11)N2—C21—C22114.1 (4)
N1—Ti1—Cl283.20 (11)N2—C21—H21A108.7
O1—Ti1—Cl190.46 (5)C22—C21—H21A108.7
N2—Ti1—Cl1103.37 (14)N2—C21—H21B108.7
N1—Ti1—Cl1154.52 (11)C22—C21—H21B108.7
Cl2—Ti1—Cl189.73 (7)H21A—C21—H21B107.6
Ti1—O1—Ti1i180.00C21—C22—H22A109.5
C13—N1—C11112.5 (5)C21—C22—H22B109.5
C13—N1—Ti1120.1 (5)H22A—C22—H22B109.5
C11—N1—Ti1108.2 (3)C21—C22—H22C109.5
C13—N1—H1A104.9H22A—C22—H22C109.5
C11—N1—H1A104.9H22B—C22—H22C109.5
Ti1—N1—H1A104.9N2—C23—C24113.4 (4)
C12—C11—N1117.3 (5)N2—C23—H23A108.9
C12—C11—H11A108.0C24—C23—H23A108.9
N1—C11—H11A108.0N2—C23—H23B108.9
C12—C11—H11B108.0C24—C23—H23B108.9
N1—C11—H11B108.0H23A—C23—H23B107.7
H11A—C11—H11B107.2C23—C24—H24A109.5
C11—C12—H12A109.5C23—C24—H24B109.5
C11—C12—H12B109.5H24A—C24—H24B109.5
H12A—C12—H12B109.5C23—C24—H24C109.5
C11—C12—H12C109.5H24A—C24—H24C109.5
H12A—C12—H12C109.5H24B—C24—H24C109.5
H12B—C12—H12C109.5C13—C14—H14A109.5
C14—C13—N1120.3 (6)C13—C14—H14B109.5
C14—C13—H13A107.3H14A—C14—H14B109.5
N1—C13—H13A107.3C13—C14—H14C109.5
C14—C13—H13B107.3H14A—C14—H14C109.5
N1—C13—H13B107.3H14B—C14—H14C109.5
Symmetry codes: (i) −x+1/2, −y+1/2, −z+1/2.
references
References top

Addison, A. W., Rao, T. N., Reedijk, J., van Rijn, J. & Verschoor, G. C. (1984). J. Chem. Soc. Dalton Trans. pp. 1349–1356.

Bruker (2003). SMART (Version 5.632) and SAINT (Version 6.45A). Bruker AXS Inc., Madison, Wisconsin, USA.

Honzíček, J., Vinklárek, J., Erben, M. & Císařová, I. (2004). Acta Cryst. E60, m1090–m1091.

Krug, V. & Müller, U. (1990). Acta Cryst. C46, 547–549.

Levason, W., Popham, M. C., Reid, G. & Webster, M. (2003). J. Chem. Soc. Dalton Trans. pp. 291–294.

Mahrwald, R., Ziemer, B. & Troyanov, S. (2001). Tetrahedron Lett. 42, 6843–6845.

Schormann, M. (2003). Acta Cryst. E59, m674–m675.

Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.

Sheldrick, G. M. (2003a). SADABS. Version 2.10. University of Göttingen, Germany.

Sheldrick, G. M. (2003b). SHELXTL. Version 6.14. Bruker AXS Inc., Madison, Wisconsin, USA.

Thewalt, U. & Schomburg, D. (1977). J. Organomet. Chem. 127, 169–74.