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Acta Cryst. (2013). E69, m88    [ doi:10.1107/S1600536812051707 ]

Tetrabromido[4-(triphenylphosphanyloxy)butyl]tellurium acetonitrile monosolvate

S. M. Närhi, R. Oilunkaniemi and R. S. Laitinen

Abstract top

In the title compound, [TeBr4(C22H23OP)]·CH3CN, the Te atom exhibits a square-pyramidal coordination with an apical Te-C bond and four basal Te-Br bonds. The conformation of the aliphatic C-C-C-C chain is gauche [torsion angle = -67.7 (8)°]. A weak C-H...Br interaction helps to establish the conformation. In the crystal, there is a weak secondary bonding interaction [Te...N = 3.456 (11) Å] between the Te atom and the N atom of the solvent molecule, which completes a distorted TeNCBr4 octahedron. Inversion dimers linked by pairs of C-H...Br interactions are also observed.

Comment top

The formation of Ph3PO(CH2)4TeBr4 has been reported earlier by us (Kunnari et al. 2001). The formally zwitterionic compound was isolated by treating TeBr4 with an equimolar amount of triphenylphosphine in tetrahydrofuran. The compound was crystallized from dichloromethane and its molecular structure was determined as a dichloromethane solvate. The title compound was recrystallized from acetonitrile and consequently contains acetonitrile solvent molecules. It is isomorphic with the CH2Cl2 solvate.

The molecular structure of the title compound indicating the numbering of the atoms is shown in Fig. 1. The Te—Br bond lengths range from 2.6652 (10) to 2.7201 (10) Å. The Te—C bond length is 2.176 (7) Å and the P—O bond length is 1.568 (5) Å. These can be compared to the bond lengths in the corresponding CH2Cl2 solvate in which the Te—Br bond lengths range 2.6776 (8) - 2.6952 (9) Å, Te—C bond length is 2.177 (6) Å, and P—O bond length is 1.581 (4) Å (Kunnari et al. 2001).

The closest internuclear contact from tellurium atom to the nitrogen atom of the solvent molecule is 3.456 (11) Å expanding the square pyramidal coordination polyhedron into a distorted octahedron. This is typical for Te···N secondary bonding interactions (Cozzolino et al. 2011). Interestingly, the Te..N interaction is stronger [Pauling (1960) bond order is 0.15] compared to the Te..Cl interaction in the CH2Cl2 solvate (Kunnari et al. 2001), for which the contact is 4.175 (3) Å corresponding to the Pauling bond order of only 0.09. This is also reflected in the C—Te—E (E = N, Cl) bond angles which are 165.0 (3) and 144.0 (1) °, respectively.

Intra- and intermolecular hydrogen bonds link the zwitterions into a three- dimensional network, as shown in Fig. 2. The shortest intermolecular C—H···Br contacts span a range of 2.75 (1)–2.96 (1) Å and the short C—H..N contacts are 2.68 (1) and 2.96 (1) Å.

Related literature top

For the formation of Ph3PO(CH2)4TeBr4 and the structure of the dichloromethane monosolvate see Kunnari et al. (2001). For Te···N interactions, see: Cozzolino et al. (2011); Pauling (1960).

Experimental top

Yellow plates of the title compound were obtained from the acetonitrile solution of Ph3PO(CH2)4TeBr4 by slow evaporation of the solvent.

Refinement top

H atoms were positioned geometrically and refined using a riding model with C—H = 0.99 Å and with Uiso(H) = 1.2 Ueq(C), 0.98 Å and Uiso(H) = 1.5 Ueq(C) and 0.95 Å and Uiso(H) = 1.2 Ueq(C)for the methylene, methyl and aromatic H atoms, respectively.

Computing details top

Data collection: COLLECT (Bruker, 2008); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: WinGX (Farrugia, 2012).

Figures top
[Figure 1] Fig. 1. The molecular structure with displacement ellipsoids drawn at 50% probability.
[Figure 2] Fig. 2. The packing of the zwitterions and the solvent indicating the short inter- and intramolecular contacts < 3.00 Å.
Tetrabromo[4-(triphenylphosphanyloxy)butyl]tellurium acetonitrile monosolvate top
Crystal data top
[TeBr4(C22H23OP)]·C2H3NF(000) = 1568
Mr = 822.67Dx = 1.928 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3714 reflections
a = 9.3195 (19) Åθ = 2.3–25.0°
b = 13.899 (3) ŵ = 6.76 mm−1
c = 21.962 (4) ÅT = 150 K
β = 94.92 (3)°Plate, yellow
V = 2834.3 (10) Å30.10 × 0.10 × 0.05 mm
Z = 4
Data collection top
Bruker–Nonius KappaCCD
diffractometer		4684 independent reflections
Radiation source: fine-focus sealed tube3714 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.073
φ scans, and ω scans with κ offsetsθmax = 25.0°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)		h = −11→10
Tmin = 0.551, Tmax = 0.729k = −15→16
11187 measured reflectionsl = −24→26
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)] = 0.048H-atom parameters constrained
wR(F2) = 0.135 w = 1/[σ2(Fo2) + (0.0606P)2 + 8.1058P]
where P = (Fo2 + 2Fc2)/3
S = 1.07(Δ/σ)max < 0.001
4684 reflectionsΔρmax = 0.88 e Å−3
291 parametersΔρmin = −0.79 e Å−3
0 restraintsExtinction correction: SHELXS97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0024 (3)
Crystal data top
[TeBr4(C22H23OP)]·C2H3NV = 2834.3 (10) Å3
Mr = 822.67Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.3195 (19) ŵ = 6.76 mm−1
b = 13.899 (3) ÅT = 150 K
c = 21.962 (4) Å0.10 × 0.10 × 0.05 mm
β = 94.92 (3)°
Data collection top
Bruker–Nonius KappaCCD
diffractometer		4684 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2008)		3714 reflections with I > 2σ(I)
Tmin = 0.551, Tmax = 0.729Rint = 0.073
11187 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.048H-atom parameters constrained
wR(F2) = 0.135Δρmax = 0.88 e Å−3
S = 1.07Δρmin = −0.79 e Å−3
4684 reflectionsAbsolute structure: ?
291 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
Te10.55868 (5)0.29462 (3)−0.09855 (2)0.02466 (19)
Br10.40006 (9)0.21866 (6)−0.19512 (3)0.0335 (2)
Br20.50893 (9)0.14024 (6)−0.03152 (4)0.0356 (2)
Br30.59404 (9)0.45190 (6)−0.16944 (4)0.0388 (2)
Br40.71342 (9)0.37800 (6)−0.00436 (4)0.0380 (2)
P10.0720 (2)0.26347 (14)0.10968 (8)0.0248 (4)
O10.0848 (5)0.2852 (3)0.0403 (2)0.0275 (11)
C10.1193 (8)0.3822 (5)0.0189 (3)0.0288 (17)
H1A0.21670.40170.03610.035*
H1B0.04880.42950.03210.035*
C20.1130 (8)0.3783 (6)−0.0504 (3)0.0303 (17)
H2A0.12020.4447−0.06600.036*
H2B0.01770.3527−0.06600.036*
C30.2297 (7)0.3172 (5)−0.0764 (3)0.0269 (16)
H3A0.23020.2520−0.05820.032*
H3B0.20900.3108−0.12120.032*
C40.3740 (8)0.3632 (5)−0.0625 (3)0.0285 (17)
H4A0.39300.3671−0.01750.034*
H4B0.36800.4300−0.07810.034*
C11−0.0254 (8)0.1540 (5)0.1093 (3)0.0281 (16)
C12−0.0930 (9)0.1166 (6)0.0554 (4)0.041 (2)
H12−0.08530.14850.01760.049*
C13−0.1719 (10)0.0320 (6)0.0577 (4)0.049 (2)
H13−0.22020.00650.02140.059*
C14−0.1801 (9)−0.0147 (6)0.1125 (4)0.042 (2)
H14−0.2315−0.07370.11340.050*
C15−0.1146 (9)0.0226 (6)0.1663 (4)0.0385 (19)
H15−0.1236−0.00980.20390.046*
C16−0.0364 (9)0.1066 (5)0.1656 (3)0.0329 (18)
H160.00930.13230.20240.039*
C21−0.0209 (8)0.3556 (5)0.1456 (3)0.0284 (17)
C22−0.1690 (8)0.3508 (5)0.1482 (3)0.0304 (17)
H22−0.22040.29600.13230.036*
C23−0.2421 (9)0.4246 (6)0.1736 (3)0.0371 (19)
H23−0.34320.42020.17580.045*
C24−0.1682 (9)0.5055 (6)0.1959 (3)0.0356 (19)
H24−0.21890.55700.21280.043*
C25−0.0214 (9)0.5113 (6)0.1936 (4)0.039 (2)
H250.02880.56650.20960.046*
C260.0539 (9)0.4379 (5)0.1684 (3)0.0340 (18)
H260.15510.44280.16650.041*
C310.2498 (8)0.2506 (5)0.1460 (3)0.0294 (17)
C320.2787 (9)0.2633 (6)0.2092 (3)0.0364 (19)
H320.20410.28090.23390.044*
C330.4197 (9)0.2496 (6)0.2351 (4)0.040 (2)
H330.44150.25930.27770.048*
C340.5280 (9)0.2221 (6)0.1991 (4)0.042 (2)
H340.62330.21320.21720.050*
C350.4976 (9)0.2076 (6)0.1372 (4)0.045 (2)
H350.57090.18670.11280.054*
C360.3595 (8)0.2239 (6)0.1110 (4)0.0371 (19)
H360.33970.21650.06810.044*
N10.8684 (11)0.1649 (8)−0.1169 (5)0.075 (3)
C50.7977 (12)0.1025 (8)−0.1349 (5)0.052 (2)
C60.7060 (13)0.0250 (8)−0.1577 (6)0.073 (3)
H6A0.6813−0.0153−0.12350.110*
H6B0.7565−0.0139−0.18640.110*
H6C0.61770.0515−0.17880.110*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Te10.0209 (3)0.0284 (3)0.0246 (3)0.00017 (19)0.00156 (19)−0.00170 (19)
Br10.0357 (5)0.0387 (5)0.0257 (4)−0.0025 (3)0.0001 (3)−0.0071 (3)
Br20.0376 (5)0.0335 (5)0.0356 (4)0.0018 (3)0.0013 (3)0.0055 (3)
Br30.0325 (5)0.0403 (5)0.0441 (5)−0.0040 (4)0.0061 (3)0.0102 (4)
Br40.0295 (5)0.0459 (5)0.0370 (4)−0.0024 (4)−0.0062 (3)−0.0085 (4)
P10.0229 (10)0.0277 (10)0.0240 (9)−0.0022 (8)0.0038 (7)0.0036 (8)
O10.029 (3)0.027 (3)0.026 (3)0.000 (2)0.001 (2)0.004 (2)
C10.034 (4)0.027 (4)0.026 (4)−0.001 (3)0.003 (3)0.007 (3)
C20.030 (4)0.034 (4)0.027 (4)−0.002 (3)0.002 (3)0.002 (3)
C30.023 (4)0.036 (4)0.023 (4)0.000 (3)0.008 (3)−0.002 (3)
C40.024 (4)0.029 (4)0.033 (4)0.001 (3)0.005 (3)−0.001 (3)
C110.032 (4)0.025 (4)0.027 (4)−0.001 (3)0.003 (3)0.002 (3)
C120.048 (5)0.043 (5)0.029 (4)−0.010 (4)−0.008 (4)0.003 (4)
C130.055 (6)0.044 (5)0.046 (5)−0.015 (4)−0.017 (4)0.000 (4)
C140.027 (5)0.030 (4)0.067 (6)−0.005 (3)0.001 (4)−0.001 (4)
C150.043 (5)0.032 (4)0.043 (5)−0.008 (4)0.014 (4)0.000 (4)
C160.040 (5)0.034 (4)0.026 (4)−0.004 (4)0.009 (3)−0.001 (3)
C210.031 (4)0.031 (4)0.022 (4)0.003 (3)−0.002 (3)−0.003 (3)
C220.026 (4)0.036 (4)0.029 (4)−0.004 (3)0.001 (3)0.001 (3)
C230.037 (5)0.043 (5)0.033 (4)0.004 (4)0.012 (4)0.008 (4)
C240.053 (6)0.033 (4)0.022 (4)0.014 (4)0.009 (4)0.001 (3)
C250.047 (5)0.031 (4)0.036 (4)−0.001 (4)−0.002 (4)−0.001 (4)
C260.039 (5)0.029 (4)0.035 (4)0.002 (3)0.007 (4)0.003 (3)
C310.027 (4)0.026 (4)0.034 (4)−0.003 (3)−0.002 (3)0.009 (3)
C320.040 (5)0.039 (5)0.029 (4)0.003 (4)−0.004 (3)0.004 (4)
C330.036 (5)0.036 (5)0.045 (5)−0.006 (4)−0.008 (4)0.013 (4)
C340.030 (5)0.049 (5)0.045 (5)−0.003 (4)−0.006 (4)0.014 (4)
C350.028 (5)0.058 (6)0.051 (5)−0.008 (4)0.006 (4)0.004 (4)
C360.024 (4)0.047 (5)0.040 (4)−0.001 (4)0.002 (3)0.005 (4)
N10.071 (7)0.074 (7)0.084 (7)0.010 (6)0.031 (6)−0.015 (6)
C50.054 (6)0.050 (6)0.054 (6)0.021 (5)0.015 (5)0.006 (5)
C60.071 (8)0.057 (7)0.088 (8)0.016 (6)−0.016 (6)−0.019 (6)
Geometric parameters (Å, º) top
Te1—C42.176 (7)C15—H150.9500
Te1—Br22.6652 (10)C16—H160.9500
Te1—Br42.6814 (11)C21—C221.387 (11)
Te1—Br12.6944 (11)C21—C261.410 (10)
Te1—Br32.7201 (10)C22—C231.375 (11)
P1—O11.568 (5)C22—H220.9500
P1—C211.769 (7)C23—C241.386 (11)
P1—C111.772 (7)C23—H230.9500
P1—C311.785 (8)C24—C251.375 (12)
O1—C11.473 (8)C24—H240.9500
C1—C21.518 (10)C25—C261.380 (11)
C1—H1A0.9900C25—H250.9500
C1—H1B0.9900C26—H260.9500
C2—C31.529 (10)C31—C361.382 (11)
C2—H2A0.9900C31—C321.403 (10)
C2—H2B0.9900C32—C331.399 (11)
C3—C41.497 (10)C32—H320.9500
C3—H3A0.9900C33—C341.388 (12)
C3—H3B0.9900C33—H330.9500
C4—H4A0.9900C34—C351.380 (12)
C4—H4B0.9900C34—H340.9500
C11—C121.394 (10)C35—C361.383 (11)
C11—C161.412 (10)C35—H350.9500
C12—C131.390 (11)C36—H360.9500
C12—H120.9500N1—C51.140 (14)
C13—C141.375 (12)C5—C61.438 (15)
C13—H130.9500C6—H6A0.9800
C14—C151.384 (12)C6—H6B0.9800
C14—H140.9500C6—H6C0.9800
C15—C161.378 (11)
C4—Te1—Br288.4 (2)C13—C14—H14119.4
C4—Te1—Br485.4 (2)C15—C14—H14119.4
Br2—Te1—Br491.68 (3)C16—C15—C14120.2 (8)
C4—Te1—Br193.5 (2)C16—C15—H15119.9
Br2—Te1—Br190.55 (3)C14—C15—H15119.9
Br4—Te1—Br1177.46 (3)C15—C16—C11118.9 (7)
C4—Te1—Br389.7 (2)C15—C16—H16120.5
Br2—Te1—Br3176.86 (3)C11—C16—H16120.5
Br4—Te1—Br390.61 (3)C22—C21—C26119.2 (7)
Br1—Te1—Br387.11 (3)C22—C21—P1120.7 (6)
O1—P1—C21112.0 (3)C26—C21—P1120.0 (6)
O1—P1—C11104.1 (3)C23—C22—C21120.7 (7)
C21—P1—C11110.7 (4)C23—C22—H22119.7
O1—P1—C31107.9 (3)C21—C22—H22119.7
C21—P1—C31110.2 (4)C22—C23—C24120.0 (8)
C11—P1—C31111.8 (3)C22—C23—H23120.0
C1—O1—P1121.6 (4)C24—C23—H23120.0
O1—C1—C2107.2 (6)C25—C24—C23120.0 (7)
O1—C1—H1A110.3C25—C24—H24120.0
C2—C1—H1A110.3C23—C24—H24120.0
O1—C1—H1B110.3C24—C25—C26120.9 (8)
C2—C1—H1B110.3C24—C25—H25119.5
H1A—C1—H1B108.5C26—C25—H25119.5
C1—C2—C3115.3 (6)C25—C26—C21119.3 (8)
C1—C2—H2A108.5C25—C26—H26120.4
C3—C2—H2A108.5C21—C26—H26120.4
C1—C2—H2B108.5C36—C31—C32119.7 (7)
C3—C2—H2B108.5C36—C31—P1118.8 (6)
H2A—C2—H2B107.5C32—C31—P1121.4 (6)
C4—C3—C2110.0 (6)C33—C32—C31118.6 (8)
C4—C3—H3A109.7C33—C32—H32120.7
C2—C3—H3A109.7C31—C32—H32120.7
C4—C3—H3B109.7C34—C33—C32120.6 (8)
C2—C3—H3B109.7C34—C33—H33119.7
H3A—C3—H3B108.2C32—C33—H33119.7
C3—C4—Te1117.6 (5)C35—C34—C33120.3 (8)
C3—C4—H4A107.9C35—C34—H34119.9
Te1—C4—H4A107.9C33—C34—H34119.9
C3—C4—H4B107.9C34—C35—C36119.5 (8)
Te1—C4—H4B107.9C34—C35—H35120.3
H4A—C4—H4B107.2C36—C35—H35120.3
C12—C11—C16120.6 (7)C31—C36—C35121.3 (8)
C12—C11—P1121.2 (6)C31—C36—H36119.4
C16—C11—P1118.2 (6)C35—C36—H36119.4
C13—C12—C11119.1 (7)N1—C5—C6178.8 (11)
C13—C12—H12120.4C5—C6—H6A109.5
C11—C12—H12120.4C5—C6—H6B109.5
C14—C13—C12120.0 (8)H6A—C6—H6B109.5
C14—C13—H13120.0C5—C6—H6C109.5
C12—C13—H13120.0H6A—C6—H6C109.5
C13—C14—C15121.1 (8)H6B—C6—H6C109.5
C21—P1—O1—C141.9 (6)C31—P1—C21—C22−148.6 (6)
C11—P1—O1—C1161.5 (5)O1—P1—C21—C26−84.7 (6)
C31—P1—O1—C1−79.6 (6)C11—P1—C21—C26159.7 (6)
P1—O1—C1—C2−176.3 (5)C31—P1—C21—C2635.5 (7)
O1—C1—C2—C3−67.3 (8)C26—C21—C22—C23−1.0 (11)
C1—C2—C3—C4−67.7 (8)P1—C21—C22—C23−176.9 (6)
C2—C3—C4—Te1−176.9 (5)C21—C22—C23—C241.1 (12)
Br2—Te1—C4—C3−62.1 (5)C22—C23—C24—C25−1.0 (11)
Br4—Te1—C4—C3−153.9 (6)C23—C24—C25—C260.9 (12)
Br1—Te1—C4—C328.3 (6)C24—C25—C26—C21−0.8 (12)
Br3—Te1—C4—C3115.4 (5)C22—C21—C26—C250.9 (11)
O1—P1—C11—C12−11.4 (8)P1—C21—C26—C25176.8 (6)
C21—P1—C11—C12109.2 (7)O1—P1—C31—C36−24.5 (7)
C31—P1—C11—C12−127.6 (7)C21—P1—C31—C36−147.1 (6)
O1—P1—C11—C16170.5 (6)C11—P1—C31—C3689.3 (7)
C21—P1—C11—C16−69.0 (7)O1—P1—C31—C32158.1 (6)
C31—P1—C11—C1654.2 (7)C21—P1—C31—C3235.5 (7)
C16—C11—C12—C130.1 (13)C11—P1—C31—C32−88.1 (7)
P1—C11—C12—C13−178.0 (7)C36—C31—C32—C330.9 (11)
C11—C12—C13—C14−1.3 (14)P1—C31—C32—C33178.3 (6)
C12—C13—C14—C152.1 (14)C31—C32—C33—C34−1.3 (12)
C13—C14—C15—C16−1.7 (13)C32—C33—C34—C35−0.1 (13)
C14—C15—C16—C110.5 (12)C33—C34—C35—C362.1 (13)
C12—C11—C16—C150.3 (12)C32—C31—C36—C351.1 (12)
P1—C11—C16—C15178.5 (6)P1—C31—C36—C35−176.3 (6)
O1—P1—C21—C2291.2 (7)C34—C35—C36—C31−2.6 (13)
C11—P1—C21—C22−24.4 (7)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3B···Br10.992.823.450 (7)122
C26—H26···Br3i0.952.753.619 (8)152
Symmetry code: (i) −x+1, −y+1, −z.
Selected bond lengths (Å) top
Te1—C42.176 (7)Te1—Br12.6944 (11)
Te1—Br22.6652 (10)Te1—Br32.7201 (10)
Te1—Br42.6814 (11)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3B···Br10.992.823.450 (7)122
C26—H26···Br3i0.952.753.619 (8)152
Symmetry code: (i) −x+1, −y+1, −z.
Acknowledgements top

Financial support from the Academy of Finland is gratefully acknowledged.

references
References top

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