New Functionalized Borasilsesquioxanes Obtained via Metathetical Transformation of 4‐Vinylphenylborasilsesquioxanes

Abstract

We report here functionalizing borasilsesquioxanes in a cross‐metathesis reaction in the presence of a ruthenium catalyst. The procedure provides new, silsesquioxanes containing boron atoms in their structure, which may find potential application in the preparation of special materials, e.g. flame retardants for polymers, organoboron Lewis acids for catalysts and scavengers, or molecular probes. The most attractive aspect of this study was obtaining hybrid silsesquioxane systems in the metathesis reaction of styrylborasilsesquioxane with mono‐ and octavinylsilsesquioxanes as well as diborate systems with vinylborate derivatives. Most of the compounds were obtained in good yields (> 75 %) and were characterized by spectroscopic methods (NMR, MALDI‐TOF‐MS).

Silane‐Bearing Borasilsesquioxanes: Synthetic Protocol and Unsuspected Redistribution Reactions

“…Compounds A and B were obtained by a condensation reaction of Disilanolisobuthyl POSS and Tetrasilanolphenyl POSS, respectively, with 4‐vinylphenylboronic acid with azeotropic elimination of stoichiometrically formed water. This preparation strategy provides quantitative yields, details being described in our previous work [15,32] …”

“…In our previous work, we have performed cross-metathesis of borasilsesquioxanes with a variety of unsaturated silanes and boranes. [15] Hydrosilylation of unsaturated organoborane compounds bearing functional groups such as vinyl, allyl and acetylene has been reported in many publications. [34][35][36] In our previous research, we studied the reactions of obtaining silsesquioxane derivatives from unsaturated boranes in a form of vinyl-and allylboronates by hydrosilylation with SiÀ H moiety-bearing mono-and octaspherosilicates catalyzed by Karstedt's catalyst.…”

“…Their preparation is carried out using a simple hydrolytic condensation reaction of such compounds as trichlorosilanes or trialkoxysilanes. [12][13] Functionalization is most often carried out by catalytic reactions, for example, hydrosilylation, [14] metathesis, [15][16] sililative coupling. [17] Cage silsesquioxanes, due to their molecular structure and nanometric dimensions, are characterized by high dispersion properties, and their properties can be modified in a wide range by functional substituents attached to the inorganic siloxane core.…”

“…However, none of the above‐mentioned works has attempted for further modification of heterosilsesquioxanes. In our previous work, we have performed cross‐metathesis of borasilsesquioxanes with a variety of unsaturated silanes and boranes [15] …”

Silsesquioxanes in the Cosmetics Industry—Applications and Perspectives

“…The methods of modification of silsesquioxanes systems can be divided into two main groups: catalytic and non-catalytic reactions. The catalytic reactions include mainly hydrosilylation of alkene systems [ 28 ], which is commonly used in industry but also silylative coupling [ 40 ], and cross-metathesis [ 41 ], Heck coupling [ 42 ], Friedel–Crafts reaction [ 43 ], thiol-ene reaction [ 44 ], nucleophilic reactions [ 31 ], or even thermal dehydrative condensation [ 45 ]. The most common reactions for the post-functionalization of silsesquioxanes from the above mentioned are nucleophilic reactions and catalytic hydrosilylation.…”