Iridium-Catalyzed Enantioselective Vinylogous and Bisvinylogous Allenylic Substitution.

ABSTRACT: Compared to the widely explored enol silanes, the applicability of their extended variants especially as bisvinylogous nucleophiles in enantioselective catalysis has been sparse. Herein, we describe the first enantioselective vinylogous and bisvinylogous allenylic substitution using silyl dienol and trienol ethers, respectively, as a nucleophile. With racemic allenylic alcohols as the electrophile, these enantioconvergent reactions are cooperatively catalyzed by an Ir(I)/(phosphoramidite,olefin) complex and Lewis acidic La(OTf)₃ and display remarkable regio- and diastereoselectivity in most cases. The ability of such extended silyl enol ethers in distant functionalization and creation of remote stereocenters is evident from the resulting γ- and ε-allenylic unsaturated ketones, b

SUBMITTER: Mitra S 

PROVIDER: S-EPMC11600155 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature