Synthesis and Characterization of Platinasilsesquioxane Complexes and Their Reaction with Arylboronic Acid

Abstract

Phenyl(iodo)platinum complexes having a 2,2 0bipyridine (bpy) or 1,2-bis(diphenylphosphino)ethane (dppe) ligand react with incompletely condensed silsesquioxane (c-C 5 H 9 ) 7 Si 7 O 9 (OH) 3 in the presence of Ag 2 O to yield platinasilsesquioxane complexes [Pt{(c-C 5 H 9 ) 7 Si 7 O 10 (OH) 2 }(C 6 H 5 )-(L)] (1, L = bpy; 2, L = dppe). NMR spectroscopy revealed their square-planar structures with an O-coordinated silsesquioxanate ligand and O-H 3 3 3 O hydrogen bonds within the ligand. Both complexes undergo transmetalation of p-methoxyphenylboronic acid to afford unsymmetrical diarylplatinum complexes [Pt(C 6 H 4 OCH 3 -p)(C 6 H 5 )(L)] (3, L=bpy; 4, L=dppe).

The first ruthenium-silsesquioxyl complexes – synthesis, structure and mechanistic implications in silylative coupling

“…Polyhedral oligosilsesquioxanes (POSS) of the general formula (RSiO 3/2 ) n and particularly those (n = 8) containing the inorganic cubic core of Si-O-Si bonds form a class of versatile building blocks for the production of inorganic-organic materials thanks to the three-dimensional highly symmetrical nature of the POSS core. 1 The properties of the core permit a wide range of technological applications of silsesquioxanes that can be used as nanofillers for the preparation of nanostructured composites, catalysts, [2][3][4] and dendrimers, 5 as precursors for optoelectronic materials, [6][7][8][9] as dry resists in microelectronics 10 and as precursors for SiO deposition. 11 Mono-and octa-functionalized silsesquioxanes and spherosilicates have been synthesized by TM catalyzed reactions such as hydrosilylation by Si-H 12 substituted POSS and silylative coupling [13][14][15][16] by vinyl-substituted POSS with olefins, which occurs via intermediates containing a TM-silicon bond.…”