design functionalizedsilsesquioxanes are currently of high importance, herein we report the effective functionalization procedure to obtain mono-, di-, and tetrasilylalkynyl-substituted silsesquioxanes of cubic T8 and DDSQ type. The synthetic methodology is based on Ru-hydride complex that turned out to be an efficient catalyst for silylative coupling of ethynylsiloxysubstituted silsesquioxanes with
A series of double-decker silsesquioxane derivatives with four reactive functional groups were designed, efficiently synthesized, and characterized. These novel inorganic–organichybrids show highly attractive features for applications as buildingblocks with Si–O–Si rigid cores (good thermal properties) with four reactive moieties, which can be functionalized in further processes.
Stereocontrol in radical Mannich equivalents for aminosugar synthesis: haloacetal and 2-(phenylthio)vinyl tethered radical additions to α-hydroxyhydrazones
作者:Gregory K. Friestad、Tao Jiang、Gina M. Fioroni
DOI:10.1016/j.tet.2008.10.013
日期:2008.12
silicon-tethered ethynyl group to the CN bond of hydrazones, affording anti-hydrazino alcohols with a trans-2-(phenylthio)vinyl substituent. The one-pot process occurs under neutral, tin-free radical conditions, and offers stereocontrol which is complementary to the haloacetal method. Synthetic utility of the radical Mannich concept is demonstrated in a brief asymmetric synthesis of N-trifluoroacetyl-l-daunosamine