Stereo-divergent synthesis of silyl-enyneviapalladium-catalyzed coupling of alkynes and iodosilanes

Abstract

We report a palladium-catalyzed coupling reaction of alkynes and silicon electrophiles, affording stereodefined silyl-enynes. Either E- or Z-enynes can be formed in high yields and in a highly stereoselective manner...

Metal-free photocatalyzed allylic silylation of allyl acetates and chlorides

“…Furthermore, the generation process of silyl radicals produces CO 2 as the only waste, which renders silacarboxylic acids ideal silyl radical precursors for the synthesis of organosilicon compounds. 19 Continuing our research on the synthesis and reactions of organosilicon compounds, 20 we present a novel metal-free photocatalyzed allylic silylation between silacarboxylic acids and readily available allyl acetates and chlorides. 21 This environmentally benign methodology enables the synthesis of a diverse range of allylsilanes in a highly stereoselective manner (Scheme 1c).…”

Intramolecular 7-endo-dig-Selective Carbosilylation of Internal Alkynes Involving Silylium-Ion Regeneration

“…A syn -selective carbo- or silametalation is typically followed by electrophilic substitution or cross-coupling of the vinylmetal intermediate with a silicon- or carbon-based reagent, respectively. Isomerization of the initially formed syn -adduct can invert the double bond geometry of the vinylsilane product or lead to E / Z mixtures . An alternative approach to arrive at that vinylmetal intermediate is the activation of the alkyne by coordination of a carbophilic metal Lewis acid with a subsequent nucleophilic attack in anti -fashion .…”