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The structure of the title compound, [Ta2O(C2B9H11)2(C4H9­N2)4]·0.5CH2Cl2, contains two (C2B9H11)Ta[NC(Me)NMe2]2 units bridged by a nearly linear [Ta—O—Ta 163.4 (4)°] μ-oxo ligand. The dichloromethane molecule lies on a twofold axis.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S010827010100436X/gd1146sup1.cif
Contains datablocks global, III

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S010827010100436X/gd1146IIIsup2.hkl
Contains datablock III

CCDC reference: 166970

Comment top

Treating tantalum-tris(N,N-dimethylamide)-1,2-dicarbaundecaborate, (C2B9H11)Ta(NMe2)3, (I), with MeCN results in insertion of the nitrile into the metal-amide bond to give mainly tantalum-tris(N,N-dimethylacetamidinate)-1,2-dicarbaundecaborate, (C2B9H11)Ta[NC(Me)NMe2]3, (II), whose structure has been described by Broder et al. (2000). The title complex, (III), was identified as a minor product and results from hydrolysis of (II) by adventitious water. Following recrystallization, the poor solubility of (III), {(C2B9H11)Ta[NC(Me)NMe2]2}2(µ-O), in all common laboratory solvents hampered attempts to obtain supporting spectroscopic data, but the crystals proved suitable for a diffraction study. \sch

The asymmetric unit of (III) comprises two Ta atoms, each ligated by two monodentate N,N-dimethylacetamidinate ligands, [NC(Me)NMe2], and tethered by a µ-oxo bridge, plus a half-occupancy dichloromethane solvent molecule. The two Ta units are oriented mutually trans to each other to minimize the considerable steric interactions between the amidinate ligands. These factors are reflected in the almost linear [163.4 (4)°] Ta—O—Ta bond. The N,N-dimethylacetamidinate ligands are close to planar, with the mean deviations from planarity of the N—C-(C)NC2 units varying from 0.011 to 0.038 Å (s.u.s?), and the Me2N—C(Me)N bonds in the amidinate are shorter than typical N—C single bonds. The Ta—N bonds [1.855 (6) to 1.881 (6) Å] are intermediate between tantalum amido, Ta—NR2 [CSD (Allen & Kennard, 1993) mean 1.99 Å], and tantalum imido, Ta—NR (CSD mean 1.79 Å), distances.

These structural features reflect a delocalized π-bonding framework over the entire amidinate ligand and a balance between tantalum amide and tantalum imide canonical forms. The strong π-donation to the metal atom from the amidinate ligands results in a competitive weakening of the carborane to metal π-donation, and the C2B3 ring-centroid-metal distances of 2.050 (8) Å to TaA and 2.037 (7) Å to TaB are intermediate between those of the parent amide complex, (I) [2.019 (6) and 2.003 (6) Å; Batsanov et al., 1999], with moderate π-donor amide ligands, and the tris(acetamidinate), (II) [2.097 (5) Å]. There is often an orientational preference displayed by C2B9H11 ligands with respect to other ligands, as previously noted in amido (Batsanov et al., 1999, 2000), indenyl (Grädler et al., 1996; Smith & Welch, 1986), pyrollyl (Teixidor et al., 1997; Gómez et al., 1997) and carbonyl (Cowie et al., 1990) complexes. This can be described as a strong trans influence of the C2 unit of the dicarbollide, and arises from the non-equivalence of the two π-donor orbitals of the ligand. In the case of (III), the mid-point of the C—C bond of the dicarbollide is preferentially located approximately over the Ta—O vector, as quantified by the (C2 midpoint)-(C2B3 centroid)-Ta—O torsion angles, which are 11.4° to TaA and 4.6° to TaB (s.u.s?).

Related literature top

For related literature, see: Allen & Kennard (1993); Batsanov et al. (1999, 2000); Broder et al. (2000); Cowie et al. (1990); Flack (1983); Gómez et al. (1997); Grädler et al. (1996); Smith & Welch (1986); Teixidor et al. (1997).

Experimental top

MeCN containing a trace of water was added to a toluene solution of tantalum-tris(N,N-dimethylamide)-1,2-dicarbaundecaborate and brought to reflux, and heating was continued for 24 h. This solution was cooled and layered with pentane. Interdiffusion of the two solvents over a period of 2 weeks afforded bright yellow crystals of (III).

Refinement top

H atoms were included as riding atoms, with B—H = 1.12 Å and C—H = 0.98–1.00 Å. The Flack parameter (Flack, 1983) indicates racemic twinning.

Computing details top

Data collection: SMART-NT (Bruker, 1998); cell refinement: SMART-NT; data reduction: SAINT-NT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-NT (Bruker, 1998).

Figures top
[Figure 1] Fig. 1. The molecular structure of (III), with displacement ellipsoids drawn at the 40% probability level and H atoms shown as small spheres of arbitrary radii.
µ-Oxo-bis[(η5-1,2-dicarbaundecaborato)bis(N,N-dimethylacetamidinato) tantalum] dichloromethane hemisolvate top
Crystal data top
[Ta2O(C2B9H11)2(C4H9N2)4]·0.5CH2Cl2F(000) = 998
Mr = 1025.69Dx = 1.554 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
a = 11.414 (3) ÅCell parameters from 616 reflections
b = 10.769 (3) Åθ = 13.7–19.1°
c = 17.863 (5) ŵ = 5.08 mm1
β = 93.303 (6)°T = 150 K
V = 2192.1 (11) Å3Rectangular prism, colourless
Z = 20.22 × 0.12 × 0.08 mm
Data collection top
Bruker SMART CCD area-detector
diffractometer
10933 independent reflections
Radiation source: fine-focus sealed tube9396 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.042
ω scansθmax = 30.4°, θmin = 1.1°
Absorption correction: integration
(XPREP in SHELXTL-NT; Bruker, 1998)
h = 1515
Tmin = 0.381, Tmax = 0.690k = 1514
26944 measured reflectionsl = 2524
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)] = 0.035H-atom parameters constrained
wR(F2) = 0.095 w = 1/[σ2(Fo2) + (0.0485P)2 + 0.8328P]
where P = (Fo2 + 2Fc2)/3
S = 1.10(Δ/σ)max < 0.001
10933 reflectionsΔρmax = 1.34 e Å3
470 parametersΔρmin = 0.76 e Å3
3 restraintsAbsolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.41 (1)
Crystal data top
[Ta2O(C2B9H11)2(C4H9N2)4]·0.5CH2Cl2V = 2192.1 (11) Å3
Mr = 1025.69Z = 2
Monoclinic, P21Mo Kα radiation
a = 11.414 (3) ŵ = 5.08 mm1
b = 10.769 (3) ÅT = 150 K
c = 17.863 (5) Å0.22 × 0.12 × 0.08 mm
β = 93.303 (6)°
Data collection top
Bruker SMART CCD area-detector
diffractometer
10933 independent reflections
Absorption correction: integration
(XPREP in SHELXTL-NT; Bruker, 1998)
9396 reflections with I > 2σ(I)
Tmin = 0.381, Tmax = 0.690Rint = 0.042
26944 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.035H-atom parameters constrained
wR(F2) = 0.095Δρmax = 1.34 e Å3
S = 1.10Δρmin = 0.76 e Å3
10933 reflectionsAbsolute structure: Flack (1983)
470 parametersAbsolute structure parameter: 0.41 (1)
3 restraints
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*/UeqOcc. (<1)
C1A0.0730 (8)0.3083 (8)0.1802 (5)0.0332 (17)
H1A0.01370.30760.19200.040*
C2A0.1586 (7)0.2868 (7)0.2444 (5)0.0336 (17)
H2A0.12770.27290.29730.040*
TaA0.12318 (2)0.51696 (3)0.235286 (16)0.02870 (8)
B4A0.1295 (8)0.4024 (9)0.1140 (6)0.038 (2)
H4A0.07670.46530.07900.046*
B5A0.1197 (10)0.2407 (10)0.0969 (6)0.042 (2)
H5A0.06290.20100.05380.051*
B6A0.1345 (10)0.1637 (10)0.1843 (6)0.046 (2)
H6A0.08790.07490.19940.055*
B7A0.2769 (10)0.1989 (11)0.2129 (7)0.052 (3)
H7A0.32540.13090.24700.063*
B8A0.2822 (8)0.3601 (10)0.2291 (6)0.043 (2)
H8A0.33750.39240.27520.051*
B9A0.2704 (8)0.4365 (10)0.1411 (6)0.039 (2)
H9A0.31990.52270.12400.047*
B10A0.2505 (10)0.3215 (10)0.0734 (6)0.044 (3)
H10A0.28130.33530.01340.053*
B11A0.2575 (11)0.1754 (11)0.1168 (6)0.052 (3)
H11A0.29440.09190.08650.063*
B12A0.3490 (9)0.2961 (10)0.1431 (7)0.048 (3)
H12A0.44620.29340.13030.058*
N1A0.2063 (5)0.5866 (6)0.3110 (4)0.0355 (15)
C3A0.2782 (6)0.6204 (8)0.3613 (5)0.0366 (18)
C4A0.3103 (7)0.5348 (9)0.4230 (5)0.049 (2)
H4A10.28260.45070.41250.074*
H4A20.39570.53390.42600.074*
H4A30.27340.56370.47070.074*
N2A0.3222 (6)0.7322 (7)0.3610 (5)0.0476 (19)
C5A0.4113 (8)0.7723 (9)0.4141 (6)0.052 (3)
H5A10.47950.71700.40910.079*
H5A20.43600.85760.40240.079*
H5A30.37690.76850.46560.079*
C6A0.2883 (9)0.8237 (9)0.3042 (6)0.054 (2)
H6A10.22570.78890.27530.080*
H6A20.26020.89980.32940.080*
H6A30.35650.84300.27040.080*
N3A0.0867 (6)0.6596 (7)0.1824 (5)0.0410 (17)
C7A0.0746 (8)0.7447 (9)0.1302 (5)0.044 (2)
C8A0.1663 (10)0.7564 (13)0.0671 (7)0.071 (3)
H8A10.22430.68980.07080.106*
H8A20.12920.74990.01910.106*
H8A30.20540.83710.07010.106*
N4A0.0170 (7)0.8239 (7)0.1370 (4)0.0478 (19)
C9A0.0369 (10)0.9218 (11)0.0832 (6)0.067 (3)
H9A10.03780.94500.05730.101*
H9A20.09110.89200.04650.101*
H9A30.07090.99430.10950.101*
C10A0.1015 (9)0.8145 (10)0.1998 (6)0.054 (3)
H1A10.11480.72680.21230.082*
H1A20.07160.85760.24300.082*
H1A30.17560.85260.18670.082*
O10.0213 (4)0.4767 (6)0.2862 (3)0.0365 (14)
C1B0.0807 (6)0.6582 (7)0.3969 (5)0.0325 (17)
H1B0.01920.68010.35690.039*
C2B0.0695 (6)0.5361 (8)0.4452 (4)0.0317 (16)
H2B0.00100.47900.43640.038*
TaB0.17936 (2)0.48489 (3)0.331441 (15)0.02563 (7)
B4B0.2228 (7)0.6943 (8)0.3848 (5)0.0271 (17)
H4B0.25570.74570.33570.033*
B5B0.1388 (8)0.7777 (8)0.4510 (5)0.0328 (19)
H5B0.11780.87880.44380.039*
B6B0.0377 (8)0.6775 (9)0.4857 (6)0.040 (2)
H6B0.05120.71030.50060.048*
B7B0.1146 (8)0.5579 (10)0.5361 (5)0.038 (2)
H7B0.07730.51130.58550.045*
B8B0.1987 (7)0.4748 (9)0.4723 (4)0.0319 (17)
H8B0.21560.37400.48400.038*
B9B0.3036 (7)0.5770 (8)0.4350 (5)0.0285 (18)
H9B0.39420.54710.42190.034*
B10B0.2825 (7)0.7262 (8)0.4759 (5)0.0304 (18)
H10B0.35760.79230.48590.036*
B11B0.1636 (8)0.7138 (9)0.5390 (6)0.040 (2)
H11B0.16040.77080.59130.047*
B12B0.2668 (8)0.5888 (9)0.5297 (6)0.038 (2)
H12B0.33260.56390.57630.045*
N1B0.2222 (6)0.3181 (6)0.3383 (4)0.0373 (15)
C3B0.2489 (7)0.1997 (8)0.3463 (5)0.0386 (19)
C4B0.1524 (8)0.1068 (9)0.3386 (6)0.052 (2)
H4B10.15380.05450.38350.079*
H4B20.16300.05470.29450.079*
H4B30.07680.14990.33270.079*
N2B0.3569 (6)0.1652 (7)0.3604 (5)0.0450 (18)
C5B0.3932 (9)0.0381 (9)0.3676 (7)0.067 (3)
H5B10.32430.01470.37280.100*
H5B20.44690.02900.41210.100*
H5B30.43330.01340.32290.100*
C6B0.4538 (7)0.2565 (9)0.3611 (7)0.055 (3)
H6B10.44530.31590.40190.083*
H6B20.45120.30090.31310.083*
H6B30.52900.21310.36850.083*
N3B0.2642 (5)0.5332 (6)0.2491 (3)0.0338 (14)
C7B0.3439 (6)0.5639 (8)0.2044 (5)0.0353 (17)
C8B0.4616 (7)0.6033 (12)0.2364 (6)0.058 (3)
H8B10.46110.60530.29120.087*
H8B20.47990.68620.21770.087*
H8B30.52120.54420.22130.087*
N4B0.3213 (6)0.5667 (8)0.1314 (4)0.0451 (18)
C9B0.4117 (9)0.5870 (15)0.0789 (5)0.077 (4)
H9B10.45930.65890.09490.115*
H9B20.37500.60230.02880.115*
H9B30.46190.51320.07750.115*
C10B0.2081 (7)0.5310 (11)0.0991 (5)0.056 (2)
H1B10.15160.52890.13830.083*
H1B20.21340.44850.07640.083*
H1B30.18220.59130.06050.083*
Cl10.4259 (6)0.9397 (6)0.1466 (4)0.087 (2)0.50
C110.3818 (11)1.0709 (10)0.0995 (7)0.053 (5)0.50
H1110.34021.04580.05180.063*0.50
H1120.45271.11760.08680.063*0.50
Cl20.2922 (4)1.1695 (6)0.1456 (3)0.0652 (15)0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C1A0.039 (4)0.034 (4)0.027 (4)0.005 (3)0.001 (3)0.008 (3)
C2A0.041 (4)0.030 (4)0.030 (4)0.008 (3)0.002 (3)0.004 (3)
TaA0.02339 (13)0.03408 (17)0.02845 (15)0.00003 (10)0.00009 (10)0.00364 (12)
B4A0.042 (5)0.038 (5)0.033 (5)0.000 (4)0.002 (4)0.002 (4)
B5A0.048 (6)0.044 (6)0.034 (6)0.009 (4)0.003 (4)0.007 (4)
B6A0.061 (6)0.036 (5)0.039 (6)0.007 (5)0.003 (5)0.005 (4)
B7A0.052 (6)0.052 (7)0.054 (7)0.019 (5)0.011 (5)0.008 (5)
B8A0.028 (4)0.047 (6)0.054 (7)0.009 (4)0.010 (4)0.005 (5)
B9A0.028 (4)0.051 (6)0.037 (5)0.009 (4)0.007 (4)0.006 (4)
B10A0.057 (6)0.046 (6)0.028 (5)0.016 (5)0.013 (5)0.001 (4)
B11A0.067 (7)0.055 (7)0.034 (6)0.020 (6)0.008 (5)0.010 (5)
B12A0.038 (5)0.049 (6)0.056 (7)0.013 (4)0.010 (5)0.003 (5)
N1A0.027 (3)0.041 (4)0.039 (4)0.005 (3)0.003 (3)0.009 (3)
C3A0.027 (4)0.039 (4)0.043 (5)0.003 (3)0.010 (3)0.001 (4)
C4A0.047 (5)0.043 (5)0.058 (6)0.008 (4)0.010 (4)0.014 (4)
N2A0.042 (4)0.049 (5)0.051 (5)0.002 (3)0.004 (3)0.012 (4)
C5A0.047 (5)0.034 (5)0.079 (8)0.003 (4)0.027 (5)0.022 (5)
C6A0.061 (6)0.036 (5)0.065 (7)0.004 (4)0.016 (5)0.009 (5)
N3A0.041 (4)0.042 (4)0.039 (5)0.005 (3)0.001 (3)0.004 (3)
C7A0.047 (5)0.047 (5)0.037 (5)0.001 (4)0.004 (4)0.001 (4)
C8A0.057 (7)0.092 (9)0.062 (8)0.001 (6)0.006 (6)0.016 (7)
N4A0.067 (5)0.035 (4)0.042 (5)0.002 (3)0.009 (4)0.007 (3)
C9A0.082 (7)0.065 (7)0.057 (7)0.004 (6)0.022 (6)0.034 (6)
C10A0.057 (6)0.045 (6)0.059 (7)0.018 (5)0.013 (5)0.008 (5)
O10.023 (2)0.050 (4)0.035 (3)0.002 (2)0.0056 (19)0.013 (3)
C1B0.030 (4)0.029 (4)0.038 (5)0.008 (3)0.001 (3)0.007 (3)
C2B0.024 (3)0.039 (4)0.032 (4)0.004 (3)0.001 (3)0.004 (3)
TaB0.02190 (12)0.02607 (14)0.02867 (15)0.00134 (10)0.00085 (10)0.00454 (11)
B4B0.032 (4)0.028 (4)0.021 (4)0.006 (3)0.002 (3)0.001 (3)
B5B0.040 (5)0.028 (4)0.030 (5)0.005 (3)0.005 (4)0.005 (4)
B6B0.033 (5)0.043 (5)0.045 (6)0.005 (4)0.010 (4)0.004 (4)
B7B0.035 (4)0.053 (6)0.025 (4)0.011 (4)0.002 (3)0.001 (4)
B8B0.035 (4)0.032 (4)0.028 (4)0.010 (4)0.002 (3)0.001 (4)
B9B0.022 (4)0.028 (4)0.035 (5)0.001 (3)0.009 (3)0.003 (3)
B10B0.031 (4)0.029 (4)0.032 (5)0.001 (3)0.005 (4)0.003 (4)
B11B0.038 (5)0.041 (5)0.040 (6)0.007 (4)0.010 (4)0.001 (4)
B12B0.037 (5)0.036 (5)0.039 (5)0.007 (4)0.003 (4)0.004 (4)
N1B0.040 (4)0.032 (4)0.040 (4)0.003 (3)0.001 (3)0.006 (3)
C3B0.043 (5)0.035 (4)0.038 (5)0.005 (3)0.007 (4)0.006 (4)
C4B0.046 (5)0.039 (5)0.073 (7)0.016 (4)0.004 (5)0.001 (5)
N2B0.040 (4)0.033 (4)0.062 (5)0.006 (3)0.001 (4)0.001 (3)
C5B0.068 (6)0.038 (5)0.095 (9)0.021 (5)0.010 (6)0.017 (6)
C6B0.031 (4)0.043 (5)0.092 (8)0.002 (4)0.004 (5)0.005 (5)
N3B0.031 (3)0.040 (4)0.030 (3)0.001 (3)0.004 (2)0.006 (3)
C7B0.031 (4)0.041 (4)0.035 (4)0.012 (3)0.007 (3)0.001 (3)
C8B0.035 (5)0.092 (8)0.048 (6)0.005 (5)0.000 (4)0.011 (6)
N4B0.035 (3)0.073 (5)0.027 (4)0.012 (3)0.000 (3)0.000 (3)
C9B0.050 (6)0.155 (13)0.027 (5)0.029 (7)0.013 (4)0.017 (6)
C10B0.048 (5)0.075 (7)0.042 (5)0.002 (5)0.007 (4)0.003 (5)
Cl10.103 (5)0.074 (4)0.078 (4)0.004 (4)0.035 (4)0.002 (3)
C110.055 (10)0.070 (12)0.033 (9)0.053 (10)0.005 (8)0.009 (8)
Cl20.047 (3)0.090 (4)0.060 (3)0.013 (3)0.013 (2)0.002 (3)
Geometric parameters (Å, º) top
C1A—C2A1.565 (12)C1B—B4B1.694 (11)
C1A—B4A1.660 (13)C1B—B6B1.701 (13)
C1A—B6A1.712 (13)C1B—B5B1.720 (12)
C1A—B5A1.714 (13)C1B—TaB2.504 (7)
C1A—TaA2.531 (8)C1B—H1B1.0001
C1A—H1A1.0001C2B—B8B1.663 (11)
C2A—B8A1.626 (13)C2B—B7B1.691 (11)
C2A—B7A1.717 (13)C2B—B6B1.733 (12)
C2A—B6A1.737 (13)C2B—TaB2.510 (7)
C2A—TaA2.518 (8)C2B—H2B1.0001
C2A—H2A1.0001TaB—N1B1.863 (7)
TaA—N1A1.855 (6)TaB—N3B1.881 (6)
TaA—N3A1.862 (8)TaB—B9B2.473 (8)
TaA—O11.887 (5)TaB—B4B2.487 (8)
TaA—B9A2.466 (9)TaB—B8B2.515 (8)
TaA—B8A2.477 (9)B4B—B10B1.761 (12)
TaA—B4A2.491 (10)B4B—B9B1.777 (12)
B4A—B9A1.746 (14)B4B—B5B1.805 (12)
B4A—B10A1.754 (13)B4B—H4B1.1200
B4A—B5A1.772 (14)B5B—B6B1.722 (14)
B4A—H4A1.1200B5B—B11B1.724 (14)
B5A—B10A1.758 (16)B5B—B10B1.764 (12)
B5A—B11A1.778 (16)B5B—H5B1.1200
B5A—B6A1.785 (16)B6B—B11B1.722 (14)
B5A—H5A1.1200B6B—B7B1.774 (14)
B6A—B7A1.772 (17)B6B—H6B1.1200
B6A—B11A1.801 (15)B7B—B11B1.770 (14)
B6A—H6A1.1200B7B—B8B1.774 (13)
B7A—B11A1.761 (17)B7B—B12B1.779 (12)
B7A—B8A1.762 (16)B7B—H7B1.1200
B7A—B12A1.792 (17)B8B—B12B1.752 (12)
B7A—H7A1.1200B8B—B9B1.783 (12)
B8A—B9A1.787 (15)B8B—H8B1.1200
B8A—B12A1.812 (15)B9B—B12B1.771 (14)
B8A—H8A1.1200B9B—B10B1.788 (12)
B9A—B10A1.753 (15)B9B—H9B1.1200
B9A—B12A1.760 (14)B10B—B12B1.780 (13)
B9A—H9A1.1200B10B—B11B1.819 (13)
B10A—B12A1.746 (16)B10B—H10B1.1200
B10A—B11A1.758 (16)B11B—B12B1.803 (14)
B10A—H10A1.1200B11B—H11B1.1200
B11A—B12A1.748 (18)B12B—H12B1.1200
B11A—H11A1.1200N1B—C3B1.318 (11)
B12A—H12A1.1200C3B—N2B1.298 (11)
N1A—C3A1.303 (10)C3B—C4B1.489 (11)
C3A—N2A1.305 (11)C4B—H4B10.9800
C3A—C4A1.499 (12)C4B—H4B20.9800
C4A—H4A10.9800C4B—H4B30.9800
C4A—H4A20.9800N2B—C5B1.433 (11)
C4A—H4A30.9800N2B—C6B1.480 (11)
N2A—C6A1.481 (13)C5B—H5B10.9800
N2A—C5A1.494 (11)C5B—H5B20.9800
C5A—H5A10.9800C5B—H5B30.9800
C5A—H5A20.9800C6B—H6B10.9800
C5A—H5A30.9800C6B—H6B20.9800
C6A—H6A10.9800C6B—H6B30.9800
C6A—H6A20.9800N3B—C7B1.288 (9)
C6A—H6A30.9800C7B—N4B1.315 (10)
N3A—C7A1.320 (12)C7B—C8B1.491 (12)
C7A—N4A1.349 (12)C8B—H8B10.9800
C7A—C8A1.499 (14)C8B—H8B20.9800
C8A—H8A10.9800C8B—H8B30.9800
C8A—H8A20.9800N4B—C10B1.436 (11)
C8A—H8A30.9800N4B—C9B1.450 (11)
N4A—C10A1.440 (12)C9B—H9B10.9800
N4A—C9A1.453 (12)C9B—H9B20.9800
C9A—H9A10.9800C9B—H9B30.9800
C9A—H9A20.9800C10B—H1B10.9800
C9A—H9A30.9800C10B—H1B20.9800
C10A—H1A10.9800C10B—H1B30.9800
C10A—H1A20.9800Cl1—C111.705 (9)
C10A—H1A30.9800C11—Cl21.718 (9)
O1—TaB1.936 (4)C11—H1110.9900
C1B—C2B1.582 (11)C11—H1120.9900
C2A—C1A—B4A112.3 (7)C2B—C1B—B5B110.9 (6)
C2A—C1A—B6A63.8 (6)B4B—C1B—B5B63.8 (5)
B4A—C1A—B6A116.3 (7)B6B—C1B—B5B60.5 (5)
C2A—C1A—B5A113.4 (7)C2B—C1B—TaB71.8 (4)
B4A—C1A—B5A63.4 (6)B4B—C1B—TaB69.6 (4)
B6A—C1A—B5A62.8 (6)B6B—C1B—TaB133.5 (5)
C2A—C1A—TaA71.5 (4)B5B—C1B—TaB130.7 (5)
B4A—C1A—TaA69.4 (4)C2B—C1B—H1B120.6
B6A—C1A—TaA133.5 (6)B4B—C1B—H1B119.5
B5A—C1A—TaA130.4 (6)B6B—C1B—H1B114.1
C2A—C1A—H1A119.7B5B—C1B—H1B117.2
B4A—C1A—H1A119.6TaB—C1B—H1B99.1
B6A—C1A—H1A112.8C1B—C2B—B8B113.0 (6)
B5A—C1A—H1A115.7C1B—C2B—B7B112.3 (6)
TaA—C1A—H1A99.7B8B—C2B—B7B63.9 (5)
C1A—C2A—B8A112.2 (7)C1B—C2B—B6B61.5 (5)
C1A—C2A—B7A110.7 (7)B8B—C2B—B6B115.5 (6)
B8A—C2A—B7A63.5 (6)B7B—C2B—B6B62.4 (6)
C1A—C2A—B6A62.2 (6)C1B—C2B—TaB71.4 (4)
B8A—C2A—B6A115.7 (7)B8B—C2B—TaB70.8 (4)
B7A—C2A—B6A61.7 (6)B7B—C2B—TaB132.0 (5)
C1A—C2A—TaA72.4 (4)B6B—C2B—TaB131.1 (5)
B8A—C2A—TaA69.7 (4)C1B—C2B—H2B120.9
B7A—C2A—TaA130.4 (6)B8B—C2B—H2B118.3
B6A—C2A—TaA132.8 (6)B7B—C2B—H2B115.3
C1A—C2A—H2A120.9B6B—C2B—H2B115.2
B8A—C2A—H2A119.1TaB—C2B—H2B99.2
B7A—C2A—H2A117.0N1B—TaB—N3B100.0 (3)
B6A—C2A—H2A114.2N1B—TaB—O1102.6 (3)
TaA—C2A—H2A99.2N3B—TaB—O1101.3 (2)
N1A—TaA—N3A100.1 (3)N1B—TaB—B9B101.5 (3)
N1A—TaA—O1102.2 (3)N3B—TaB—B9B100.1 (3)
N3A—TaA—O1102.7 (3)O1—TaB—B9B144.2 (3)
N1A—TaA—B9A106.4 (3)N1B—TaB—B4B143.4 (3)
N3A—TaA—B9A96.1 (3)N3B—TaB—B4B87.1 (3)
O1—TaA—B9A142.2 (3)O1—TaB—B4B111.2 (3)
N1A—TaA—B8A84.5 (3)B9B—TaB—B4B42.0 (3)
N3A—TaA—B8A136.4 (3)N1B—TaB—C1B144.2 (3)
O1—TaA—B8A118.9 (3)N3B—TaB—C1B115.1 (3)
B9A—TaA—B8A42.4 (3)O1—TaB—C1B78.2 (2)
N1A—TaA—B4A147.6 (3)B9B—TaB—C1B66.8 (3)
N3A—TaA—B4A87.9 (3)B4B—TaB—C1B39.7 (3)
O1—TaA—B4A106.6 (3)N1B—TaB—C2B107.4 (3)
B9A—TaA—B4A41.2 (3)N3B—TaB—C2B151.2 (3)
B8A—TaA—B4A68.9 (3)O1—TaB—C2B81.4 (2)
N1A—TaA—C2A105.1 (3)B9B—TaB—C2B66.3 (3)
N3A—TaA—C2A152.3 (3)B4B—TaB—C2B65.7 (3)
O1—TaA—C2A83.2 (3)C1B—TaB—C2B36.8 (3)
B9A—TaA—C2A66.0 (3)N1B—TaB—B8B83.4 (3)
B8A—TaA—C2A38.0 (3)N3B—TaB—B8B140.8 (3)
B4A—TaA—C2A64.7 (3)O1—TaB—B8B116.2 (2)
N1A—TaA—C1A141.2 (3)B9B—TaB—B8B41.9 (3)
N3A—TaA—C1A118.2 (3)B4B—TaB—B8B69.6 (3)
O1—TaA—C1A76.8 (3)C1B—TaB—B8B65.2 (3)
B9A—TaA—C1A65.4 (3)C2B—TaB—B8B38.6 (3)
B8A—TaA—C1A63.9 (3)C1B—B4B—B10B104.4 (6)
B4A—TaA—C1A38.6 (3)C1B—B4B—B9B104.2 (6)
C2A—TaA—C1A36.1 (3)B10B—B4B—B9B60.7 (5)
C1A—B4A—B9A104.9 (7)C1B—B4B—B5B58.8 (5)
C1A—B4A—B10A104.8 (7)B10B—B4B—B5B59.3 (5)
B9A—B4A—B10A60.1 (6)B9B—B4B—B5B107.6 (6)
C1A—B4A—B5A59.8 (5)C1B—B4B—TaB70.7 (4)
B9A—B4A—B5A108.8 (7)B10B—B4B—TaB126.1 (5)
B10A—B4A—B5A59.8 (6)B9B—B4B—TaB68.6 (4)
C1A—B4A—TaA72.0 (4)B5B—B4B—TaB126.9 (5)
B9A—B4A—TaA68.6 (5)C1B—B4B—H4B125.5
B10A—B4A—TaA126.0 (6)B10B—B4B—H4B119.9
B5A—B4A—TaA129.6 (6)B9B—B4B—H4B124.0
C1A—B4A—H4A124.6B5B—B4B—H4B118.8
B9A—B4A—H4A124.1TaB—B4B—H4B102.5
B10A—B4A—H4A120.4C1B—B5B—B6B59.2 (5)
B5A—B4A—H4A117.2C1B—B5B—B11B104.5 (7)
TaA—B4A—H4A101.3B6B—B5B—B11B60.0 (6)
C1A—B5A—B10A102.4 (7)C1B—B5B—B10B103.2 (6)
C1A—B5A—B4A56.8 (5)B6B—B5B—B10B110.2 (7)
B10A—B5A—B4A59.6 (6)B11B—B5B—B10B62.9 (5)
C1A—B5A—B11A103.2 (8)C1B—B5B—B4B57.4 (5)
B10A—B5A—B11A59.6 (6)B6B—B5B—B4B108.5 (6)
B4A—B5A—B11A106.8 (8)B11B—B5B—B4B109.5 (6)
C1A—B5A—B6A58.5 (5)B10B—B5B—B4B59.1 (5)
B10A—B5A—B6A108.4 (8)C1B—B5B—H5B126.1
B4A—B5A—B6A107.2 (7)B6B—B5B—H5B120.5
B11A—B5A—B6A60.7 (6)B11B—B5B—H5B121.0
C1A—B5A—H5A126.6B10B—B5B—H5B121.6
B10A—B5A—H5A122.9B4B—B5B—H5B121.8
B4A—B5A—H5A122.5C1B—B6B—B11B105.4 (7)
B11A—B5A—H5A122.7C1B—B6B—B5B60.3 (5)
B6A—B5A—H5A120.8B11B—B6B—B5B60.1 (5)
C1A—B6A—C2A54.0 (5)C1B—B6B—C2B54.9 (5)
C1A—B6A—B7A101.7 (7)B11B—B6B—C2B104.0 (6)
C2A—B6A—B7A58.6 (6)B5B—B6B—C2B103.8 (6)
C1A—B6A—B5A58.7 (6)C1B—B6B—B7B102.9 (6)
C2A—B6A—B5A102.2 (7)B11B—B6B—B7B60.8 (5)
B7A—B6A—B5A106.7 (8)B5B—B6B—B7B108.4 (6)
C1A—B6A—B11A102.3 (7)C2B—B6B—B7B57.6 (5)
C2A—B6A—B11A102.4 (8)C1B—B6B—H6B125.0
B7A—B6A—B11A59.1 (7)B11B—B6B—H6B122.4
B5A—B6A—B11A59.4 (6)B5B—B6B—H6B121.5
C1A—B6A—H6A126.6C2B—B6B—H6B126.2
C2A—B6A—H6A126.4B7B—B6B—H6B122.5
B7A—B6A—H6A123.0C2B—B7B—B11B103.7 (7)
B5A—B6A—H6A122.6C2B—B7B—B6B60.0 (5)
B11A—B6A—H6A124.2B11B—B7B—B6B58.1 (6)
C2A—B7A—B11A104.9 (8)C2B—B7B—B8B57.3 (5)
C2A—B7A—B8A55.7 (5)B11B—B7B—B8B108.4 (6)
B11A—B7A—B8A108.0 (9)B6B—B7B—B8B108.1 (7)
C2A—B7A—B6A59.7 (6)C2B—B7B—B12B102.0 (6)
B11A—B7A—B6A61.3 (7)B11B—B7B—B12B61.1 (5)
B8A—B7A—B6A107.4 (7)B6B—B7B—B12B106.8 (7)
C2A—B7A—B12A103.1 (7)B8B—B7B—B12B59.1 (5)
B11A—B7A—B12A58.9 (7)C2B—B7B—H7B125.9
B8A—B7A—B12A61.3 (7)B11B—B7B—H7B122.4
B6A—B7A—B12A108.5 (8)B6B—B7B—H7B121.7
C2A—B7A—H7A126.0B8B—B7B—H7B121.6
B11A—B7A—H7A122.0B12B—B7B—H7B123.4
B8A—B7A—H7A122.2C2B—B8B—B12B104.4 (7)
B6A—B7A—H7A120.5C2B—B8B—B7B58.8 (5)
B12A—B7A—H7A122.6B12B—B8B—B7B60.6 (5)
C2A—B8A—B7A60.7 (6)C2B—B8B—B9B104.5 (6)
C2A—B8A—B9A105.2 (7)B12B—B8B—B9B60.1 (5)
B7A—B8A—B9A107.7 (8)B7B—B8B—B9B109.2 (6)
C2A—B8A—B12A106.0 (7)C2B—B8B—TaB70.5 (4)
B7A—B8A—B12A60.1 (7)B12B—B8B—TaB124.4 (5)
B9A—B8A—B12A58.5 (6)B7B—B8B—TaB127.0 (5)
C2A—B8A—TaA72.4 (4)B9B—B8B—TaB67.8 (4)
B7A—B8A—TaA130.3 (6)C2B—B8B—H8B125.4
B9A—B8A—TaA68.5 (4)B12B—B8B—H8B120.2
B12A—B8A—TaA124.7 (6)B7B—B8B—H8B117.5
C2A—B8A—H8A123.2B9B—B8B—H8B123.8
B7A—B8A—H8A116.9TaB—B8B—H8B103.5
B9A—B8A—H8A125.3B12B—B9B—B4B106.6 (6)
B12A—B8A—H8A120.9B12B—B9B—B8B59.1 (5)
TaA—B8A—H8A101.4B4B—B9B—B8B106.7 (5)
B4A—B9A—B10A60.2 (6)B12B—B9B—B10B60.0 (5)
B4A—B9A—B12A107.7 (8)B4B—B9B—B10B59.2 (5)
B10A—B9A—B12A59.6 (6)B8B—B9B—B10B107.0 (6)
B4A—B9A—B8A105.4 (7)B12B—B9B—TaB125.9 (5)
B10A—B9A—B8A107.5 (8)B4B—B9B—TaB69.4 (4)
B12A—B9A—B8A61.5 (6)B8B—B9B—TaB70.3 (4)
B4A—B9A—TaA70.2 (4)B10B—B9B—TaB125.5 (5)
B10A—B9A—TaA127.4 (6)B12B—B9B—H9B119.5
B12A—B9A—TaA128.0 (6)B4B—B9B—H9B123.8
B8A—B9A—TaA69.1 (4)B8B—B9B—H9B123.3
B4A—B9A—H9A123.9B10B—B9B—H9B119.4
B10A—B9A—H9A118.8TaB—B9B—H9B103.0
B12A—B9A—H9A117.9B4B—B10B—B5B61.6 (5)
B8A—B9A—H9A123.9B4B—B10B—B12B106.9 (6)
TaA—B9A—H9A102.0B5B—B10B—B12B106.0 (6)
B12A—B10A—B9A60.4 (6)B4B—B10B—B9B60.1 (5)
B12A—B10A—B4A108.0 (7)B5B—B10B—B9B109.0 (6)
B9A—B10A—B4A59.7 (5)B12B—B10B—B9B59.5 (5)
B12A—B10A—B5A109.0 (8)B4B—B10B—B11B107.2 (6)
B9A—B10A—B5A109.1 (7)B5B—B10B—B11B57.5 (5)
B4A—B10A—B5A60.6 (6)B12B—B10B—B11B60.1 (5)
B12A—B10A—B11A59.8 (7)B9B—B10B—B11B108.1 (6)
B9A—B10A—B11A108.5 (8)B4B—B10B—H10B121.5
B4A—B10A—B11A108.5 (7)B5B—B10B—H10B122.1
B5A—B10A—B11A60.8 (7)B12B—B10B—H10B122.8
B12A—B10A—H10A121.6B9B—B10B—H10B121.1
B9A—B10A—H10A121.4B11B—B10B—H10B122.6
B4A—B10A—H10A121.8B6B—B11B—B5B60.0 (6)
B5A—B10A—H10A120.6B6B—B11B—B7B61.1 (5)
B11A—B10A—H10A121.4B5B—B11B—B7B108.5 (7)
B12A—B11A—B10A59.7 (7)B6B—B11B—B12B108.0 (7)
B12A—B11A—B7A61.4 (7)B5B—B11B—B12B106.8 (7)
B10A—B11A—B7A108.2 (8)B7B—B11B—B12B59.7 (5)
B12A—B11A—B5A108.0 (8)B6B—B11B—B10B107.7 (7)
B10A—B11A—B5A59.6 (6)B5B—B11B—B10B59.7 (5)
B7A—B11A—B5A107.5 (7)B7B—B11B—B10B107.3 (7)
B12A—B11A—B6A109.1 (7)B12B—B11B—B10B58.9 (5)
B10A—B11A—B6A107.7 (7)B6B—B11B—H11B121.3
B7A—B11A—B6A59.6 (6)B5B—B11B—H11B122.0
B5A—B11A—B6A59.8 (6)B7B—B11B—H11B121.3
B12A—B11A—H11A120.9B12B—B11B—H11B122.6
B10A—B11A—H11A122.1B10B—B11B—H11B122.5
B7A—B11A—H11A121.5B8B—B12B—B9B60.8 (5)
B5A—B11A—H11A122.2B8B—B12B—B7B60.3 (5)
B6A—B11A—H11A121.7B9B—B12B—B7B109.5 (6)
B10A—B12A—B11A60.4 (7)B8B—B12B—B10B108.7 (7)
B10A—B12A—B9A60.0 (6)B9B—B12B—B10B60.4 (5)
B11A—B12A—B9A108.6 (8)B7B—B12B—B10B108.6 (7)
B10A—B12A—B7A107.4 (8)B8B—B12B—B11B107.9 (6)
B11A—B12A—B7A59.7 (7)B9B—B12B—B11B109.5 (7)
B9A—B12A—B7A107.6 (7)B7B—B12B—B11B59.2 (5)
B10A—B12A—B8A106.7 (7)B10B—B12B—B11B61.0 (5)
B11A—B12A—B8A106.4 (7)B8B—B12B—H12B121.5
B9A—B12A—B8A60.0 (6)B9B—B12B—H12B120.5
B7A—B12A—B8A58.5 (6)B7B—B12B—H12B121.5
B10A—B12A—H12A122.0B10B—B12B—H12B121.1
B11A—B12A—H12A121.7B11B—B12B—H12B121.6
B9A—B12A—H12A121.2C3B—N1B—TaB177.0 (7)
B7A—B12A—H12A122.5N2B—C3B—N1B120.6 (8)
B8A—B12A—H12A123.1N2B—C3B—C4B121.0 (8)
C3A—N1A—TaA170.0 (6)N1B—C3B—C4B118.4 (8)
N1A—C3A—N2A120.9 (8)C3B—C4B—H4B1109.5
N1A—C3A—C4A121.7 (8)C3B—C4B—H4B2109.5
N2A—C3A—C4A117.4 (8)H4B1—C4B—H4B2109.5
C3A—C4A—H4A1109.5C3B—C4B—H4B3109.5
C3A—C4A—H4A2109.5H4B1—C4B—H4B3109.5
H4A1—C4A—H4A2109.5H4B2—C4B—H4B3109.5
C3A—C4A—H4A3109.5C3B—N2B—C5B123.9 (8)
H4A1—C4A—H4A3109.5C3B—N2B—C6B120.8 (7)
H4A2—C4A—H4A3109.5C5B—N2B—C6B114.9 (7)
C3A—N2A—C6A120.1 (8)N2B—C5B—H5B1109.5
C3A—N2A—C5A122.7 (8)N2B—C5B—H5B2109.5
C6A—N2A—C5A117.2 (8)H5B1—C5B—H5B2109.5
N2A—C5A—H5A1109.5N2B—C5B—H5B3109.5
N2A—C5A—H5A2109.5H5B1—C5B—H5B3109.5
H5A1—C5A—H5A2109.5H5B2—C5B—H5B3109.5
N2A—C5A—H5A3109.5N2B—C6B—H6B1109.5
H5A1—C5A—H5A3109.5N2B—C6B—H6B2109.5
H5A2—C5A—H5A3109.5H6B1—C6B—H6B2109.5
N2A—C6A—H6A1109.5N2B—C6B—H6B3109.5
N2A—C6A—H6A2109.5H6B1—C6B—H6B3109.5
H6A1—C6A—H6A2109.5H6B2—C6B—H6B3109.5
N2A—C6A—H6A3109.5C7B—N3B—TaB166.0 (6)
H6A1—C6A—H6A3109.5N3B—C7B—N4B121.0 (7)
H6A2—C6A—H6A3109.5N3B—C7B—C8B119.2 (8)
C7A—N3A—TaA165.0 (7)N4B—C7B—C8B119.7 (7)
N3A—C7A—N4A119.2 (8)C7B—C8B—H8B1109.5
N3A—C7A—C8A119.5 (9)C7B—C8B—H8B2109.5
N4A—C7A—C8A121.2 (9)H8B1—C8B—H8B2109.5
C7A—C8A—H8A1109.5C7B—C8B—H8B3109.5
C7A—C8A—H8A2109.5H8B1—C8B—H8B3109.5
H8A1—C8A—H8A2109.5H8B2—C8B—H8B3109.5
C7A—C8A—H8A3109.5C7B—N4B—C10B120.8 (7)
H8A1—C8A—H8A3109.5C7B—N4B—C9B122.6 (7)
H8A2—C8A—H8A3109.5C10B—N4B—C9B116.0 (8)
C7A—N4A—C10A120.4 (8)N4B—C9B—H9B1109.5
C7A—N4A—C9A123.3 (9)N4B—C9B—H9B2109.5
C10A—N4A—C9A116.3 (9)H9B1—C9B—H9B2109.5
N4A—C9A—H9A1109.5N4B—C9B—H9B3109.5
N4A—C9A—H9A2109.5H9B1—C9B—H9B3109.5
H9A1—C9A—H9A2109.5H9B2—C9B—H9B3109.5
N4A—C9A—H9A3109.5N4B—C10B—H1B1109.5
H9A1—C9A—H9A3109.5N4B—C10B—H1B2109.5
H9A2—C9A—H9A3109.5H1B1—C10B—H1B2109.5
N4A—C10A—H1A1109.5N4B—C10B—H1B3109.5
N4A—C10A—H1A2109.5H1B1—C10B—H1B3109.5
H1A1—C10A—H1A2109.5H1B2—C10B—H1B3109.5
N4A—C10A—H1A3109.5Cl1—C11—Cl2116.3 (8)
H1A1—C10A—H1A3109.5Cl1—C11—H111108.2
H1A2—C10A—H1A3109.5Cl2—C11—H111108.2
TaA—O1—TaB163.4 (4)Cl1—C11—H112108.2
C2B—C1B—B4B111.7 (6)Cl2—C11—H112108.2
C2B—C1B—B6B63.6 (5)H111—C11—H112107.4
B4B—C1B—B6B114.9 (6)

Experimental details

Crystal data
Chemical formula[Ta2O(C2B9H11)2(C4H9N2)4]·0.5CH2Cl2
Mr1025.69
Crystal system, space groupMonoclinic, P21
Temperature (K)150
a, b, c (Å)11.414 (3), 10.769 (3), 17.863 (5)
β (°) 93.303 (6)
V3)2192.1 (11)
Z2
Radiation typeMo Kα
µ (mm1)5.08
Crystal size (mm)0.22 × 0.12 × 0.08
Data collection
DiffractometerBruker SMART CCD area-detector
diffractometer
Absorption correctionIntegration
(XPREP in SHELXTL-NT; Bruker, 1998)
Tmin, Tmax0.381, 0.690
No. of measured, independent and
observed [I > 2σ(I)] reflections
26944, 10933, 9396
Rint0.042
(sin θ/λ)max1)0.712
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.095, 1.10
No. of reflections10933
No. of parameters470
No. of restraints3
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.34, 0.76
Absolute structureFlack (1983)
Absolute structure parameter0.41 (1)

Computer programs: SMART-NT (Bruker, 1998), SMART-NT, SAINT-NT (Bruker, 1998), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL-NT (Bruker, 1998).

 

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