1,3-Bis(3-phenyl­prop­yl)-1H-benz­imidazole-2(3H)-tellurone

Şerife Pınar Yalçın; Mehmet Akkurt; Ülkü Yılmaz; Hasan Küçükbay; Orhan Büyükgüngör

doi:10.1107/S1600536808004893

. 2008 Feb 22;64(Pt 3):o621–o622. doi: 10.1107/S1600536808004893

1,3-Bis(3-phenylpropyl)-1H-benzimidazole-2(3H)-tellurone

Şerife Pınar Yalçın ^a, Mehmet Akkurt ^a,^*, Ülkü Yılmaz ^b, Hasan Küçükbay ^b, Orhan Büyükgüngör ^c

PMCID: PMC2960818 PMID: 21201955

Abstract

The title compound, C₂₅H₂₆N₂Te, was synthesized from bis[1,3-bis(3-phenylpropyl)benzimidazolidin-2-ylidene] and Te in a toluene solution. The molecule possesses a twofold rotation axis passing through the Te atom and the center of the benzimidazole ring system. The benzimidazole ring system makes an angle of 67.9 (4)° with the phenyl rings.

Related literature

For related literature, see: Akkurt et al. (2004a ▶,b ▶, 2005 ▶); Aydın et al. (1999 ▶); Chakravorty et al. (1985 ▶); Karaca et al. (2005 ▶); Lappert (1988 ▶); Lappert et al. (1980 ▶); Roeterdink et al. (1983 ▶); Türktekin et al. (2004 ▶); İngeç et al. (1999 ▶); Närhi et al. (2004 ▶); Sadekov et al. (1998 ▶); Singh et al. (2006 ▶).

Experimental

Crystal data

C₂₅H₂₆N₂Te
M _r = 482.08
Tetragonal,
a = 10.6004 (2) Å
c = 20.4365 (6) Å
V = 2296.42 (9) Å³
Z = 4
Mo Kα radiation
μ = 1.31 mm⁻¹
T = 296 K
0.54 × 0.48 × 0.39 mm

Data collection

Stoe IPDSII diffractometer
Absorption correction: integration (X-RED32; Stoe & Cie, 2002 ▶) T _min = 0.539, T _max = 0.630
28301 measured reflections
2264 independent reflections
2166 reflections with I > 2σ(I)
R _int = 0.049

Refinement

R[F ² > 2σ(F ²)] = 0.037
wR(F ²) = 0.105
S = 1.09
2264 reflections
99 parameters
3 restraints
H-atom parameters constrained
Δρ_max = 0.92 e Å⁻³
Δρ_min = −0.48 e Å⁻³
Absolute structure: Flack (1983 ▶), 889 Friedel pairs
Flack parameter: 0.01 (6)

Data collection: X-AREA (Stoe & Cie, 2002 ▶); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2002 ▶); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808004893/ez2117sup1.cif

e-64-0o621-sup1.cif^{(18.4KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808004893/ez2117Isup2.hkl

e-64-0o621-Isup2.hkl^{(109.1KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Te1—C1

2.058 (4)

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Acknowledgments

The authors acknowledge the Faculty of Arts and Sciences, Ondokuz Mayıs University, Turkey, for the use of the Stoe IPDSII diffractometer (purchased under grant F.279 of the University Research Fund). ÜY and HK also thank the İnönü University Research Fund (BAPB-2006–41) for financial support of this study.

supplementary crystallographic information

Comment

Electron-rich olefins are powerful reducing agents (Lappert, 1988). It is known that the ultimate oxidation products of electron-rich olefins with air are ureas; sulfur and selenium react similarly to form the corresponding analogues (Roeterdink et al., 1983; Lappert et al., 1980). The conversion of an electron-rich olefin into a tellurourea has a parallel in these known olefin reactions (Lappert et al., 1980). There are extensive studies of cyclic ureas containing imidazolidine groups, including their X-ray crystal structures. However, there is no example of an X-ray crystal structure study for the cyclic tellurourea containing a benzimidazole group. The objective of this study was to elucidate the first crystal structure of such a cyclic tellurourea and compare the results to the corresponding analogues contain sulfur (İngeç et al., 1999) and selenium (Aydın et al., 1999; Akkurt et al., 2004a).

The molecular structure of the title compound (I) is shown in Fig. 1. The molecule has a twofold screw axis through the midpoints of the C2—C2a and C4—C4a bonds and containing the atoms Te1 and C1 of the benzimidazole ring. The Te—C single bond length generally varies between 2.120 and 2.170 Å depending on the electron releasing effect of the ligand bonding to Te atom (Lappert et al., 1980; Sadekov et al., 1998; Närhi et al., 2004; Singh et al., 2006). In the title compound (I), the Te—C bond length [2.058 (4) Å] is short, which agrees with the results reported by Lappert et al. (1980). Tellurourea metal complexes may be described in terms of the resonance hybrids as shown in the scheme 2. For this reason, the Te?C bond may have partial double bond character.

All the geometric parameters of (I) are comparable with those in related compounds (Akkurt et al., 2004b; Akkurt et al., 2005; Türktekin et al., 2004, Karaca et al., 2005).

In the title molecule, the benzimidazole ring system (C1—C3/N1/C1a—C3a/N1a) is essentially planar, with maximum deviations of 0.007 (5) Å for C2 and -0.007 (5) Å for C2a. The symmetry-related phenyl rings (C8–C13 and C8a–C13a) are oriented at angles of 67.9 (4)° to the plane of the benzimidazole ring system.

Experimental

A mixture of bis(1,3-di(3-phenylpropyl)benzimidazolidine-2-ylidene) (0.55 g; 0.78 mmol) and tellurium (0.22 g; 1.72 mmol) in toluene (10 ml) was heated under reflux for 2 h. The mixture was then filtered to remove unreacted tellurium and upon cooling the filtrate to 253 K, light yellow crystals of the title compound were obtained. (Yield: 0.54 g, 72%; m.p.: 390–391 K). ¹H-NMR (CDCl₃): δ 2.25 (q, 4H, CH₂), 2.83 (t, 4H, CH₂), 4.53 (t, 4H, N—CH₂), 7.14–7.24 (m, 14H, Ar—H). ¹³C-NMR (CDCl₃): δ 29.74, 32.99, 49.25, 110.26, 123.61, 126.20, 128.38, 128.50, 133.93, 140.73, 144.18. Analysis calculated for C₂₅H₂₆N₂Te: C 62.29, H 5.40, N 5.82%. Found: C 62.52, H 5.50, N 5.82%.