Alkenyl-Functionalized Open-Cage Silsesquioxanes (RSiMe2O)3R′7Si7O9: A Novel Class of Building Nanoblocks

Trifunctional incompletely condensed polyhedral oligomeric silsesquioxanes (RSiMe 2 O) 3 R' 7 Si 7 O 9 ( IC-POSS s) are considered as intriguing building nanoblocks dedicated to constructing highly advanced organic-inorganic molecules and polymers. Up to now, they have been mainly obtained via hydrosilylation of olefins, while the hydrosilylation of the C≡C bonds has not been studied at all, despite the enormous potential of this approach resulting from the possibility of introducing 3, 6, or even more functional groups into the IC-POSS structure. Therefore, in this work, we present a highly selective and efficient synthesis of the first example of tripodal alkenyl-functionalized IC-POSS s, obtained via platinum-catalyzed hydrosilylation of the terminal and internal alkynes, as well as symmetrically and nonsymmetrically 1,4-disubstituted buta-1,3-diynes with silsesquioxanes (HSiMe 2 O) 3 R' 7 Si 7 O 9 (R' = i -C 4 H 9 ( 1a ), (H 3 C) 3 CH 2 C(H 3 C)HCH 2 C ( 1b )). The resulting products are synthetic intermediates that contain C═C bonds and functional groups (e.g., OSiMe 3 , SiR 3 , Br, F, B(O(C(CH 3 ) 2 ) 2 (Bpin)), thienyl), which make them suitable for application in the synthesis of novel, complex, hybrid materials with unique properties.