Transition-metal-catalyzed silylene expulsion from, and/or rearrangement of, oligosilanes

Synthesis and Properties of Intramolecularly Base-Stabilized (Disilanyl−silylene)ruthenium and -iron Complexes

“…Isolation of the products was unsuccessful because they were extremely sensitive to air. However, if we take into account the photolysis of CpFe(CO) 2 SiMe 2 SiMe 2 SiMe 2 SiMe 3 leading to rearrangement into CpFe(CO) 2 Si(SiMe 3 ) 3 , reported by Pannell et al,10a the result implies that the photolysis of 6 yielded several intramolecularly methoxy-stabilized silylene complexes accompanied by the extensive scrambling of substituents.…”

“…Pannell et al. reported the photochemical rearrangement of linear polysilanyl groups in CpFe(CO) 2 (SiMe 2 ) n Me ( n ≥ 3) into branched ones . They explained the results reasonably by 1,3-migration of substituents on (polysilanyl−silylene)iron intermediates formed via a mechanism analogous to mechanism A.…”

“…In contrast to the case for disilanyl complexes, the photoreactions of complexes having trisilanyl or longer polysilanyl ligands have scarcely been investigated. Pannell et al extensively studied the photochemical rearrangement of linear polysilanyl complexes to branched ones, but isolation or stabilization of the proposed intermediates, i.e., polysilanyl−silylene complexes, has never been accomplished. We report herein the photolysis of (methoxytrisilanyl)ruthenium and -iron complexes giving intramolecularly base-stabilized (disilanyl−silylene)ruthenium and -iron complexes, and the X-ray crystal structure of one of them.…”

Ruthenium-Catalyzed Demethanative Coupling of HGeMe3: A High Yield Route to Polygermanes

“…16 As an alternative, Ge-Ge bond formation could be accomplished by the reverse of an R-migration step: germyl to germylene migration. An analogous process, silyl to silylene migration, has been proposed in the photolysis of transition metal substituted disilanes 17 and in the reversible scrambling of a CD 3 group between silicon atoms in (dcpe)Pt(H)(SiMe 2 SiMe 3 ). 18 In addition, the migration of a silyl group from a tantalum center to an alkylidene has been observed.…”

The tris(trimethylsilyl)silyl group in organic, coordination and organometallic chemistry

“…208 This reaction occurs via the formation of silyl-silylene complexes (Z 5 -Cp)Fe(CO)(=SiMe 2 )(Si n Me 2n+1 ) with subsequent migration of the silyl and methyl groups. The photochemical isomerisation of nonamethyltetrasilane, H(SiMe 2 ) 4 Me, in the presence of catalytic amounts of (Z 5 -Cp)Fe(CO) 2 SiMe 3 or carbonyls Fe(CO) 5 , W(CO) 6 initially results in (Me 3 Si) 3 SiH, which is further converted into the dimethylsilylene insertion product with insertion into the Si7H bond, (Me 3 Si) 3 SiSiMe 2 H. 209 Thermal isomerisation in the presence of catalytic amounts of (Z 5 -Cp)Fe. .…”