1,3-Difunctionalization of Propargyl Silanes with Concomitant 1,2-Silyl Shift: Synthesis of Allyl Functionalized Vinyl Silanes.

Rūdolfs Beļaunieks, Mikus Puriņš, Rebeka Anna Līpiņa, Anatoly Mishnev, Māris Turks

Organic letters 2023 Jun 30

filter terms:

Terminal alkynes with a silyl group at the propargylic position upon activation with electrophiles such as N-bromosuccinimide undergo (E)-selective 1,2-silyl group migration. Subsequently, an allyl cation is formed that is intercepted by an external nucleophile. This approach provides allyl ethers and esters with stereochemically defined vinyl halide and silane handles for further functionalization. The scope of propargyl silanes and electrophile-nucleophile pairs are investigated, and various trisubstituted olefins are prepared in up to 78% yield. The obtained products have been demonstrated to serve as building blocks for transition-metal-catalyzed cross-couplings of vinyl halides, silicon-halogen exchange, and allyl acetate functionalization reactions.

Citation

Rūdolfs Beļaunieks, Mikus Puriņš, Rebeka Anna Līpiņa, Anatoly Mishnev, Māris Turks. 1,3-Difunctionalization of Propargyl Silanes with Concomitant 1,2-Silyl Shift: Synthesis of Allyl Functionalized Vinyl Silanes. Organic letters. 2023 Jun 30;25(25):4627-4631