Crystal structure of (tert-butyl­dimethyl­sil­yl)tri­phenyl­germane, Ph3Ge-SiMe2(t-Bu)

Kirill V Zaitsev; Galina S Zaitseva; Sergey S Karlov; Alexander A Korlyukov

doi:10.1107/S2056989015022872

. 2015 Dec 6;71(Pt 12):o1015–o1016. doi: 10.1107/S2056989015022872

Crystal structure of (tert-butyldimethylsilyl)triphenylgermane, Ph₃Ge-SiMe₂(t-Bu)

Kirill V Zaitsev ^a, Galina S Zaitseva ^a, Sergey S Karlov ^a,^*, Alexander A Korlyukov ^b

PMCID: PMC4719953 PMID: 26870472

Abstract

In the title compound, Ph₃Ge-SiMe₂(t-Bu) or C₂₄H₃₀GeSi, the Si and Ge atoms both possess a tetrahedral coordination environment with C—E—C (E = Si, Ge) angles in the range 104.47 (5)–114.67 (5)°. The molecule adopts an eclipsed conformation, with three torsion angles less than 29.5°. In the crystal, neighbouring molecules are combined to dimers by six T-shaped C—H⋯π interactions, forming sixfold phenyl embraces (6PE).

Keywords: catenated compounds, silagermanes, C—H⋯π interactions, 6PE interactions, crystal structure

Related literature

For general background to the chemistry of Group 14 element catenated compounds, see: Marschner & Hlina (2013 ▸); Amadoruge & Weinert (2008 ▸); Párkányi et al. (1986 ▸); Leigh et al. (1997 ▸). As apart of our studies of the chemistry of oligogermanium compounds (Zaitsev et al. 2012 ▸, 2013 ▸, 2014a ▸,b ▸), the title compound was obtained and studied. For related crystal structures of silagermanes, see: Zaitsev et al. (2015 ▸). The 6PE interactions are intensively discussed in Scudder & Dance (2000 ▸); Steiner (2000 ▸); Churakov et al. (2005 ▸).

Experimental

Crystal data

C₂₄H₃₀GeSi
M _r = 419.16
Monoclinic,
a = 13.5332 (6) Å
b = 14.9825 (7) Å
c = 22.7179 (13) Å
β = 106.2048 (10)°
V = 4423.3 (4) Å³
Z = 8
Mo Kα radiation
μ = 1.44 mm⁻¹
T = 120 K
0.32 × 0.29 × 0.24 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2013 ▸) T _min = 0.720, T _max = 0.862
32242 measured reflections
7990 independent reflections
6137 reflections with I > 2σ(I)
R _int = 0.043

Refinement

R[F ² > 2σ(F ²)] = 0.033
wR(F ²) = 0.071
S = 1.01
7990 reflections
240 parameters
H-atom parameters constrained
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.37 e Å⁻³

Data collection: APEX2 (Bruker, 2013 ▸); cell refinement: SAINT (Bruker, 2013 ▸); data reduction: SAINT; program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015 ▸); molecular graphics: OLEX2 (Dolomanov et al., 2009 ▸); software used to prepare material for publication: OLEX2.

Supplementary Material

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989015022872/im2474sup1.cif

e-71-o1015-sup1.cif^{(606KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015022872/im2474Isup2.hkl

e-71-o1015-Isup2.hkl^{(671.1KB, hkl)}

Click here for additional data file.^{(3KB, mol)}

Supporting information file. DOI: 10.1107/S2056989015022872/im2474Isup3.mol

Click here for additional data file.^{(7.5KB, cml)}

Supporting information file. DOI: 10.1107/S2056989015022872/im2474Isup4.cml

Click here for additional data file.^{(1.9MB, tif)}

. DOI: 10.1107/S2056989015022872/im2474fig1.tif

Molecular structure of the title compound, with displacement ellipsoids shown at the 50% probability level.

Click here for additional data file.^{(1.2MB, tif)}

. DOI: 10.1107/S2056989015022872/im2474fig2.tif

Dimers formed by 6PE interactions between adjacent molecules.

CCDC reference: 1439529

Additional supporting information: crystallographic information; 3D view; checkCIF report

Acknowledgments

This work was supported financially by the Russian President Grant for Young Russian Scientists (MK-1790.2014.3)

supplementary crystallographic information

S1. Structural commentary

In the title compound, Ph₃Ge-SiMe₂(t-Bu), both Si and Ge atoms possess tetrahedral coordination environments with C—E—C angles ranging within 104.47 (5)- 114.67 (5) °. The Ge—Si bond length (2.4026 (4) Å) is slightly longer than in the closely related compound Ph₃Ge-SiMe₃ (2.384 (1) Å (Párkányi et al., 1986). The molecule adopts an eclipsed conformation with three torsion angles less than 29.5°.

In the crystal, neighbouring molecules are combined to dimers by six T-shaped C—H···π interactions forming sixfold phenyl embraces (6PE, Steiner, 2000; Churakov et al., 2005). As expected for 6PE-bonded molecules, the C_ax—Ge···Ge angle is almost linear − 175.9° (Fig. 2; Scudder & Dance, 2000).

The title compound is isostructural with the corresponding silicon complex Ph₃Si-SiMe₂(t-Bu) (Leigh et al., 1997).

S2. Synthesis and crystallization

The synthetic procedure leading to the title compound was reported by us earlier (Zaitsev et al., 2014b) to give a white crystalline material in good yield (86%) by the reaction of Ph₃GeLi (generated in situ from equimolar amounts of Ph₃GeH and n-BuLi at room temperature in Et₂O) with t-BuMe₂SiCl in diethyl ether. Solvent-free crystals of the title compound suitable for X-Ray analysis were obtained after recrystallization from n-hexane at room temperature.

S3. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. A l l non-hydrogen atoms were refined with anisotropic thermal parameters.

All hydrogen atoms were placed in calculated positions and refined using a riding model, with C—H = 0.93–0.96 Å, and with U_iso(H) = 1.2 U_eq(C) for aromatic H atoms or 1.5 U_eq(C) for methyl H atoms. A rotating model was applied to the methyl groups.