supplementary materials


jj2114 scheme

Acta Cryst. (2012). E68, o215-o216    [ doi:10.1107/S1600536811054560 ]

Dibromidochlorido{2-[(dimethylamino)methyl]phenyl-[kappa]2N,C1}tellurium(IV)

P. Rakesh, H. B. Singh and R. J. Butcher

Abstract top

The title compound, C9H13Br2ClNTe, was synthesized by reacting [2-(dimethylaminomethyl)phenyl]tellurium(II) chloride with Br2. As a consequence, the Cl and Br atoms are not well ordered but distributed over the three possible positions such that the overall stiochiometry is two Br atoms and one Cl atom. The scrambling of the Br and Cl atoms indicates a small energy barrier for the exchange process between the apical and equatorial positions. Overall, the Te atom geometry is slightly distorted square pyramidal ([tau] = 0.052 for the major component). However, there is a weak secondary interaction between the Te atoms and the disordered Br/Cl atoms of a nearby molecule. The Te-Br and Te-Cl distances in both disorder components fall into two groups; a longer distance for the Br/Cl involved in this secondary interaction [2.6945 (17) Å for Br and 2.601 (9)Å for Cl] and shorter bond distances to the remaining halogen atoms, indicating that this interaction has slightly weakened the Te-X bond, as is the case in the previously reported tribromido structure [Singh et al. (1990). J. Chem. Soc. Dalton Trans. pp. 907-913]. Otherwise, the metrical parameters in the two structures are not significantly different. An intermolecular C-H...Br interaction occurs.

Comment top

Unlike their selenium analogues, simple aryltellurenyl halides are thermally unstable and polymeric in nature. However, it has been shown that they can be stabilized by intramolecular coordination and thus be isolated and structurally characterized (Singh & McWhinnie, 1985; Singh et al., 1990; Singh et al., 1992; Panda et al., 1999). Previously the structures {2-[(S)-1-(dimethylamino)ethyl]phenyl}tellurium(IV) trichloride (Singh et al. 1992) and 2-(dimethylaminomethyl)phenyl]tellurium(IV) tribromide (Singh et al. 1990) have been published. In this report the structure of 2-(dimethylaminomethyl)phenyl]tellurium(IV)dibromide chloride is presented in which the 2Br's and Cl are distributed over the three possible sites. The scrambling of the Br/Cl position indicates a small energy barrier for the exchange process between the axial and equatorial positions. The synthesis of similar dibromochloro derivatives of Te have been reported previously although no crystal structures were completed (Cobbledick et al., 1979; Rivkin et al., 1991).

Overall the molecule is slightly distorted square pyramidal [τ = 0.052 for the major component (Addison et al., 1984]. However there is a weak secondary interaction between the Te and Br/Cl of an adjoining molecule. The Te—Br and Te—Cl distances in both molecules fall into two groups; a longer distance for the Br/Cl involved in this secondary interaction (2.6945 (17)Å for Br and 2.601 (9)Å for Cl) and shorter bond distances to the remaining halogens, indicating that this interaction has slightly weakened the Te—X bond, as is the case in the previously reported polymorph. Otherwise, the metrical parameters in both polymorphs are not significantly different.

Related literature top

For related structures, see: Panda et al. (1999); Singh & McWhinnie (1985); Singh et al. (1992); Singh et al. (1990). For the synthesis of similar dibromidochlorido derivatives of tellurium, see: Rivkin et al. (1991); Cobbledick et al. (1979). For the asymmetry parameter, see: Addison et al. (1984). For the preparation of bis[2-(dimethylaminomethyl)phenyl]ditelluride, see: Kaur et al. (1995).

Experimental top

As shown in the reaction scheme (scheme 2), a stirred solution of bis[2-(dimethylaminomethyl)phenyl]ditelluride, 1, (Kaur et al., 1995) (0.5 g, 0.94 mmol) in diethylether (10 ml) was treated with HCl (3 ml in 20 ml distilled water). The reaction mixture was further stirred for 10 min. The resulting reaction mixture was evaporated to one third of its original volume and ethanol (5 ml) was added to get a yellow solid. It was redissolved in ethanol and stored in the refrigerator to get yellow needles of the monochloride, 2.

A stirred solution of 2 (0.2 g, 0.66 mmol) in dry CHCl3 (10 ml) was treated with Br2 (0.37 ml, 2.34 mmol) under N2 at 0° C. The reaction mixture was further stirred for 2 h and then reduced to half volume and kept in freezer to give a yellow crystalline solid, 3, which contained crystals of two morphologies. This is the structure of one of these.

Refinement top

H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms with C—H distances of 0.95 - 0.97 Å [Uiso(H) = 1.2Ueq(OH, CH, CH2) [Uiso(H) = 1.5Ueq(CH3)]. As is discussed above, the 2 Br's and Cl are distributed over the three possible positions. Initially the Br/Cl occupancy in each position was refined as a free variable. These Br and Cl occupancies summed to Br2.03 and Cl0.98. The three free variables were then constrained to match a stoichiometry of Br2 and Cl.

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Diagram of the major component of C9H12Br2ClNTe, showing atom labeling. Atomic displacement parameters are at the 30% level.
[Figure 2] Fig. 2. Diagram showing the formation of a dimer through weak Te···Br interactions. These interactions are shown as dashed lines
[Figure 3] Fig. 3. The molecular packing for C9H12Br2ClNTe viewed along the a axis. Te—Br secondary interactions are shown by dashed lines.
[Figure 4] Fig. 4. The formation of the title compound.
Dibromidochlorido{2-[(dimethylamino)methyl]phenyl- κ2N,C1}tellurium(IV) top
Crystal data top
C9H12Br2ClNTeF(000) = 848
Mr = 457.07Dx = 2.341 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3585 reflections
a = 7.2854 (3) Åθ = 5.1–32.5°
b = 12.4785 (5) ŵ = 8.63 mm1
c = 14.4098 (6) ÅT = 123 K
β = 98.200 (4)°Plate, yellow
V = 1296.61 (9) Å30.63 × 0.50 × 0.10 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur Ruby Gemini
diffractometer
4241 independent reflections
Radiation source: Enhance (Mo) X-ray Source2981 reflections with I > 2σ(I)
graphiteRint = 0.044
Detector resolution: 10.5081 pixels mm-1θmax = 32.6°, θmin = 5.4°
ω scansh = 911
Absorption correction: analytical
[CrysAlis PRO (Oxford Diffraction, 2007), based on expressions derived by Clark & Reid (1995)]
k = 1813
Tmin = 0.042, Tmax = 0.409l = 1620
8229 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.056H-atom parameters constrained
S = 0.96 w = 1/[σ2(Fo2) + (0.0084P)2]
where P = (Fo2 + 2Fc2)/3
4241 reflections(Δ/σ)max = 0.001
141 parametersΔρmax = 0.91 e Å3
1 restraintΔρmin = 0.92 e Å3
Crystal data top
C9H12Br2ClNTeV = 1296.61 (9) Å3
Mr = 457.07Z = 4
Monoclinic, P21/cMo Kα radiation
a = 7.2854 (3) ŵ = 8.63 mm1
b = 12.4785 (5) ÅT = 123 K
c = 14.4098 (6) Å0.63 × 0.50 × 0.10 mm
β = 98.200 (4)°
Data collection top
Oxford Diffraction Xcalibur Ruby Gemini
diffractometer
4241 independent reflections
Absorption correction: analytical
[CrysAlis PRO (Oxford Diffraction, 2007), based on expressions derived by Clark & Reid (1995)]
2981 reflections with I > 2σ(I)
Tmin = 0.042, Tmax = 0.409Rint = 0.044
8229 measured reflectionsθmax = 32.6°
Refinement top
R[F2 > 2σ(F2)] = 0.038H-atom parameters constrained
wR(F2) = 0.056Δρmax = 0.91 e Å3
S = 0.96Δρmin = 0.92 e Å3
4241 reflectionsAbsolute structure: ?
141 parametersFlack parameter: ?
1 restraintRogers parameter: ?
Special details top

Experimental. CrysAlisPro (Oxford Diffraction, 2007) Analytical numeric absorption correction using a multifaceted crystal model based on expressions derived by R.C. Clark & J.S. Reid. (Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887-897)

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)
Te0.51999 (3)0.349798 (17)0.583822 (16)0.01724 (6)
Br10.2864 (3)0.39052 (12)0.42535 (11)0.0262 (2)0.6585 (4)
Br20.7403 (2)0.28626 (15)0.73580 (13)0.0228 (2)0.6374 (13)
Br30.7448 (2)0.26391 (13)0.47988 (10)0.0291 (2)0.7041 (13)
Cl10.2892 (15)0.4029 (7)0.4363 (6)0.0262 (2)0.3415 (4)
Cl20.7179 (11)0.2938 (7)0.7271 (6)0.0228 (2)0.3626 (13)
Cl30.7337 (15)0.2589 (9)0.4931 (7)0.0291 (2)0.2959 (13)
N10.3019 (4)0.4005 (2)0.6881 (2)0.0190 (6)
C10.3619 (4)0.2094 (2)0.5943 (2)0.0153 (7)
C20.3578 (5)0.1257 (3)0.5303 (3)0.0212 (8)
H2A0.42920.12940.48010.025*
C30.2486 (5)0.0371 (3)0.5405 (3)0.0266 (9)
H3A0.24630.02120.49800.032*
C40.1421 (5)0.0337 (3)0.6134 (3)0.0253 (9)
H4A0.06730.02730.62030.030*
C50.1438 (5)0.1179 (3)0.6758 (3)0.0238 (8)
H5A0.06950.11480.72490.029*
C60.2551 (4)0.2077 (3)0.6667 (2)0.0180 (7)
C70.2670 (5)0.2987 (3)0.7364 (3)0.0210 (8)
H7A0.14950.30410.76320.025*
H7B0.36890.28520.78830.025*
C80.3833 (5)0.4816 (3)0.7561 (3)0.0258 (8)
H8A0.29790.49580.80140.039*
H8B0.40490.54790.72290.039*
H8C0.50140.45490.78920.039*
C90.1283 (5)0.4418 (3)0.6349 (3)0.0268 (9)
H9A0.04220.46130.67850.040*
H9B0.07190.38640.59180.040*
H9C0.15540.50520.59910.040*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Te0.02085 (12)0.01446 (11)0.01669 (11)0.00383 (10)0.00360 (9)0.00064 (9)
Br10.0431 (3)0.0156 (5)0.0177 (5)0.0027 (3)0.0030 (3)0.0001 (3)
Br20.0143 (5)0.0283 (4)0.0240 (5)0.0002 (3)0.0033 (3)0.0020 (3)
Br30.0366 (4)0.0252 (3)0.0299 (6)0.0057 (3)0.0193 (3)0.0062 (3)
Cl10.0431 (3)0.0156 (5)0.0177 (5)0.0027 (3)0.0030 (3)0.0001 (3)
Cl20.0143 (5)0.0283 (4)0.0240 (5)0.0002 (3)0.0033 (3)0.0020 (3)
Cl30.0366 (4)0.0252 (3)0.0299 (6)0.0057 (3)0.0193 (3)0.0062 (3)
N10.0209 (16)0.0156 (14)0.0207 (16)0.0032 (12)0.0037 (13)0.0001 (11)
C10.0146 (17)0.0139 (16)0.0159 (17)0.0063 (14)0.0032 (14)0.0001 (12)
C20.0176 (18)0.0156 (18)0.028 (2)0.0011 (14)0.0056 (15)0.0009 (14)
C30.027 (2)0.0149 (18)0.034 (2)0.0026 (16)0.0091 (17)0.0010 (15)
C40.0190 (19)0.0184 (18)0.035 (2)0.0076 (16)0.0087 (17)0.0080 (15)
C50.0184 (19)0.025 (2)0.026 (2)0.0041 (16)0.0018 (16)0.0085 (15)
C60.0157 (18)0.0150 (17)0.0209 (19)0.0015 (14)0.0055 (14)0.0028 (13)
C70.0185 (19)0.0224 (19)0.023 (2)0.0002 (15)0.0047 (15)0.0055 (14)
C80.025 (2)0.026 (2)0.027 (2)0.0069 (16)0.0057 (17)0.0086 (15)
C90.021 (2)0.025 (2)0.034 (2)0.0042 (16)0.0018 (17)0.0005 (16)
Geometric parameters (Å, °) top
Te—C12.114 (3)C2—H2A0.9500
Te—N12.421 (3)C3—C41.393 (5)
Te—Cl22.446 (8)C3—H3A0.9500
Te—Cl32.450 (11)C4—C51.381 (5)
Te—Cl12.601 (9)C4—H4A0.9500
Te—Br32.6027 (15)C5—C61.400 (4)
Te—Br22.6454 (15)C5—H5A0.9500
Te—Br12.6945 (17)C6—C71.511 (5)
Te—Cl1i3.414 (9)C7—H7A0.9900
Te—Br1i3.5441 (17)C7—H7B0.9900
N1—C81.473 (4)C8—H8A0.9800
N1—C91.476 (4)C8—H8B0.9800
N1—C71.488 (4)C8—H8C0.9800
C1—C61.387 (4)C9—H9A0.9800
C1—C21.391 (4)C9—H9B0.9800
C2—C31.382 (5)C9—H9C0.9800
C1—Te—N176.09 (11)C8—N1—C7110.7 (3)
C1—Te—Cl288.0 (2)C9—N1—C7110.5 (3)
N1—Te—Cl284.9 (2)C8—N1—Te110.8 (2)
C1—Te—Cl392.8 (3)C9—N1—Te111.0 (2)
N1—Te—Cl3167.3 (2)C7—N1—Te103.81 (18)
Cl2—Te—Cl388.6 (3)C6—C1—C2121.7 (3)
C1—Te—Cl188.5 (2)C6—C1—Te115.9 (2)
N1—Te—Cl192.0 (2)C2—C1—Te122.3 (2)
Cl2—Te—Cl1175.8 (3)C3—C2—C1119.2 (3)
Cl3—Te—Cl193.9 (3)C3—C2—H2A120.4
C1—Te—Br395.40 (9)C1—C2—H2A120.4
N1—Te—Br3170.80 (7)C2—C3—C4119.7 (3)
Cl2—Te—Br391.4 (2)C2—C3—H3A120.2
Cl1—Te—Br391.2 (2)C4—C3—H3A120.2
C1—Te—Br287.99 (10)C5—C4—C3120.9 (3)
N1—Te—Br286.50 (8)C5—C4—H4A119.5
Cl3—Te—Br286.9 (3)C3—C4—H4A119.5
Cl1—Te—Br2176.5 (2)C4—C5—C6119.9 (3)
Br3—Te—Br289.75 (6)C4—C5—H5A120.0
C1—Te—Br186.11 (9)C6—C5—H5A120.0
N1—Te—Br194.91 (8)C1—C6—C5118.5 (3)
Cl2—Te—Br1173.9 (2)C1—C6—C7120.2 (3)
Cl3—Te—Br190.4 (3)C5—C6—C7121.2 (3)
Br3—Te—Br187.89 (5)N1—C7—C6109.1 (3)
Br2—Te—Br1173.41 (5)N1—C7—H7A109.9
C1—Te—Cl1i171.06 (19)C6—C7—H7A109.9
N1—Te—Cl1i97.34 (17)N1—C7—H7B109.9
Cl2—Te—Cl1i97.6 (3)C6—C7—H7B109.9
Cl3—Te—Cl1i94.3 (3)H7A—C7—H7B108.3
Cl1—Te—Cl1i85.6 (3)N1—C8—H8A109.5
Br3—Te—Cl1i91.49 (17)N1—C8—H8B109.5
Br2—Te—Cl1i97.76 (16)H8A—C8—H8B109.5
Br1—Te—Cl1i88.46 (16)N1—C8—H8C109.5
C1—Te—Br1i169.81 (9)H8A—C8—H8C109.5
N1—Te—Br1i94.83 (7)H8B—C8—H8C109.5
Cl2—Te—Br1i95.9 (2)N1—C9—H9A109.5
Cl3—Te—Br1i96.7 (2)N1—C9—H9B109.5
Cl1—Te—Br1i87.2 (2)H9A—C9—H9B109.5
Br3—Te—Br1i93.93 (5)N1—C9—H9C109.5
Br2—Te—Br1i96.16 (5)H9A—C9—H9C109.5
Br1—Te—Br1i90.15 (4)H9B—C9—H9C109.5
C8—N1—C9109.9 (3)
C1—Te—N1—C8149.1 (2)Br3—Te—C1—C6161.9 (2)
Cl2—Te—N1—C859.9 (3)Br2—Te—C1—C672.3 (2)
Cl3—Te—N1—C8119.3 (12)Br1—Te—C1—C6110.6 (2)
Cl1—Te—N1—C8123.0 (3)Br1i—Te—C1—C641.9 (7)
Br2—Te—N1—C860.3 (2)N1—Te—C1—C2162.6 (3)
Br1—Te—N1—C8126.2 (2)Cl2—Te—C1—C2112.2 (4)
Cl1i—Te—N1—C837.1 (3)Cl3—Te—C1—C223.7 (4)
Br1i—Te—N1—C835.6 (2)Cl1—Te—C1—C270.1 (3)
C1—Te—N1—C988.6 (2)Br3—Te—C1—C221.0 (3)
Cl2—Te—N1—C9177.7 (3)Br2—Te—C1—C2110.5 (3)
Cl3—Te—N1—C9118.4 (12)Br1—Te—C1—C266.5 (3)
Cl1—Te—N1—C90.6 (3)Br1i—Te—C1—C2135.2 (4)
Br2—Te—N1—C9177.4 (2)C6—C1—C2—C31.9 (5)
Br1—Te—N1—C93.8 (2)Te—C1—C2—C3178.8 (2)
Cl1i—Te—N1—C985.2 (3)C1—C2—C3—C41.2 (5)
Br1i—Te—N1—C986.7 (2)C2—C3—C4—C50.0 (5)
C1—Te—N1—C730.2 (2)C3—C4—C5—C60.6 (5)
Cl2—Te—N1—C759.0 (3)C2—C1—C6—C51.3 (5)
Cl3—Te—N1—C70.4 (13)Te—C1—C6—C5178.4 (2)
Cl1—Te—N1—C7118.2 (3)C2—C1—C6—C7178.4 (3)
Br2—Te—N1—C758.60 (19)Te—C1—C6—C74.5 (4)
Br1—Te—N1—C7114.94 (19)C4—C5—C6—C10.0 (5)
Cl1i—Te—N1—C7156.0 (2)C4—C5—C6—C7177.1 (3)
Br1i—Te—N1—C7154.50 (19)C8—N1—C7—C6158.5 (3)
N1—Te—C1—C614.5 (2)C9—N1—C7—C679.5 (3)
Cl2—Te—C1—C670.7 (3)Te—N1—C7—C639.6 (3)
Cl3—Te—C1—C6159.2 (4)C1—C6—C7—N133.4 (4)
Cl1—Te—C1—C6107.0 (3)C5—C6—C7—N1149.6 (3)
Symmetry codes: (i) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C7—H7A···Br2ii0.992.963.839 (4)149.
Symmetry codes: (ii) x−1, y, z.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
C7—H7A···Br2i0.992.963.839 (4)149.
Symmetry codes: (i) x−1, y, z.
Acknowledgements top

RJB acknowledges the NSF–MRI program (grant CHE-0619278) for funds to purchase the diffractometer. HBS acknowledges the DST for funding and PR acknowledges the CSIR for a fellowship.

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.

Clark, R. C. & Reid, J. S. (1995). Acta Cryst. A51, 887–897.

Cobbledick, R. E., Einstein, F. W. B., McWhinnie, W. R. & Musa, F. H. (1979). J. Chem. Res. (S), p. 145.

Kaur, R., Singh, H. B. & Butcher, R. J. (1995). Organometallics, 14, 4755–4763.

Oxford Diffraction (2007). CrysAlis PRO, CrysAlis RED and CrysAlis CCD. Oxford Diffraction Ltd, Abingdon, England.

Panda, A., Mugesh, G., Singh, H. B. & Butcher, R. J. (1999). Organometallics, 18, 1986–1993.

Rivkin, B. B., Maksimenko, A. A. & Sadekov, I. D. (1991). Zh. Obshch. Khim. 61, 1154–1162.

Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122.

Singh, H. B. & McWhinnie, W. R. (1985). J. Chem. Soc. Dalton Trans. pp. 821–825.

Singh, H. B., Sudha, N. & Butcher, R. J. (1992). Inorg. Chem. 31, 1431–1435.

Singh, H. B., Sudha, N., West, A. A. & Hamor, T. A. (1990). J. Chem. Soc. Dalton Trans. pp. 907–913.