Tetra-kis(2,3,5,5-tetra-methyl-hexen-2-yl)silane.

In the title compound, C40H76Si, the Si atom is located on a special position of site symmetry -4. Thus, there is just a quarter of a mol-ecule in the asymmetric unit. The C=C double bonds exhibit a trans configuration.

Electrocyclic reactions of siloles: a combined experimental and theoretical study.

The reaction of 4-chloro-1,2-dimethyl-4-supersilylsila-1-cyclopentene (2 a) with Li[NiPr2] at -78 °C results in the formation of the formal 1,4-addition product of the silacyclopentadiene derivative 3,4-dimethyl-1-supersilylsila-1,3-cyclopentadiene (4 a) with 2,3-dimethyl-4-supersilylsila-1,3-cyclopentadiene (5 a). In addition the respective adducts of the Diels-Alder reactions of 4 a+4 a and 4 a+5 a were obtained. Compound 4 a, which displays an s-cis-silacyclopentadiene configuration, reacts with cyclohexene to form the racemate of the [4+2] cycloadduct of 4 a and cyclohexene (9).

Unexpected disproportionation of tetramethylethylenediamine-supported perchlorodisilane Cl3SiSiCl3.

The addition compound Cl(3)SiSiCl(3)·TMEDA was formed quantitatively by treatment of Cl(3)SiSiCl(3) with tetramethylethylenediamine (TMEDA) in pentane at room temperature. The crystal structure of Cl(3)SiSiCl(3)·TMEDA displays one tetrahedrally and one octahedrally bonded Si atom (monoclinic, P2(1)/n). (29)Si CP/MAS NMR spectroscopy confirms this structure.

trans-Dichloridobis(triphenyl-phosphane-κP)palladium(II) benzene hemisolvate.

The title complex, [PdCl(2)(C(18)H(15)P)(2)]·0.5C(6)H(6), has the Pd(II) ion in a square-planar coordination mode (r.m.

Bromido(2,4,6-trimethyl-phen-yl)mercury(II).

Mol-ecules of the title compound, [HgBr(C(9)H(11))], are located on a crystallographic twofold rotation axis. Due to the mol-ecular symmetry, the Hg(II) atom is linearly coordinated by the ipso-C of the mesityl group and the Br atom. In the crystal, mol-ecules lie in planes parallel to (001).

C-H...pi interactions in cocrystals of bis(trimethylsilyl)acetylene and diphenylacetylene with benzene.

We present here the crystal structures of two acetylene derivatives cocrystallized with benzene, namely bis(trimethylsilyl)acetylene benzene solvate, C(8)H(18)Si(2).C(6)H(6), (I), and diphenylacetylene benzene solvate, C(14)H(10).C(6)H(6), (II).