New vinylgermanium cubic derivatives of silsesquioxanes (i.e., monovinylhepta(alkyl, phenyl)-germasilsesqiuoxanes and (dimethylvinylgermoxy)-heptaisobutylsilsesquioxanes) were synthesized and characterized by spectroscopic methods. The first ruthenium− germasilsesquioxyl complexes were also prepared via stoichiometric reaction of RuHCl(CO)(PPh 3 ) 3 with the abovementioned vinylgermanium derivatives of silsesquioxanes, and their structures were determined by spectroscopic and X-ray analyses. The initial ruthenium complex as well as the above-mentioned Ge−Ru complexes were tested as catalysts, in the germylative coupling with olefins, and proved to be active in the case of (dimethylvinyl)-germoxyheptaisobutylsilsesquioxane but showed no activity toward vinylgermasilsesquioxanes. A general mechanism for the germylative coupling of the two vinylgermanium derivatives of silsesquioxanes is presented.

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Fort he first time,o lefin cross metathesis has been developed for vinylgermanium compounds. This paper also marks the first case of transition metal-catalyzed functionalization of heterosilsesquioxanes,w hich in our case are cubic vinylgermasilsesquioxanes and newly synthesizedd i(vinylgermyl)substituted double-decker silsesquioxane.T hese processes leadt oaseries of new molecular, unsaturated mono-a nd divinyl-substituted germasilsesquioxanes, which can be potentially applied as precursors for optoelectronics and for the synthesis of new advanced materials.A dditionally,p reliminary tests of metathetic copolymerization of divinylsubstituted double-deckerd igermasilsesquioxanes (DDSQ-2ViGe) with selected diolefins provedt ob ev ery promising and resulted in the synthesis of novels tereoregular trans-germasilsesquioxyl-vinylene-phenylene macromolecular derivatives.A ll newly obtained compounds were isolated andc haracterized by mass and spectroscopic methods.Scheme5.Cross-metathesis of DDSQ-2ViGe with olefins.

We report herein an efficient procedure for the synthesis of new polyhedral oligomeric silsesquioxane (POSS) derivatives as multifunctional reagents. This study concerns the incompletely condensed silsesquioxanes and germasilsesquioxanes with vinyl‐substituted silyl and germyl functional groups, which allow further modification. Furthermore, our experiments have been extended to the synthesis of a new subclass of completely condensed vinylgermasilsesquioxanes. These hybrid building blocks were obtained selectively within a few hours and isolated with excellent yields.

Hydrosilylation of a wide group of mono- and disubstituted (symmetrical and nonsymmetrical) alkynes with 1-dimethylsiloxy-3,5,7,9,11,13,15-heptaisobutylpentacyclo-[9.5.1.1.1.1]octasiloxane ((HSiMeO)(i-Bu)SiO, 1) in the presence of Karstedt's catalyst (Pt(dvs)) has been performed for the first time. A series of new 1,2-(E)-disubstituted and 1,1,2-(E)-trisubstituted ethenes with a silsesquioxane moiety were selectively afforded and fully characterized. On the basis of nuclear magnetic resonance (NMR) and infrared spectroscopy (in situ FT-IR and/or FT-IR), the influence of alkyne structure and reaction conditions on the stereoselectivity as well as on the progress of triple bond hydrosilylation catalyzed by Pt(dvs) was explained. The results of the studies clearly indicated for which reagents the developed procedures lead to alkenylsilsesquioxanes with almost stoichiometric yields in short time, and for which other catalytic systems or methods should be considered.