Silylated Vinyloxiranes – Recent Advances and Synthetic Applications

Abstract

Stereoselective preparation of α‐silylated α‐quaternary unsaturated aldehydes 2 from variously substituted silylated vinyloxiranes is achieved with the aid of palladium(0) catalysis under smooth experimental conditions. One example of a versatile application of this rearrangement reaction, in the case of the tert‐butyldimethyl(3‐vinyloxiran‐2‐yl)silane derivative 1a, has resulted in one‐pot diastereoselective syntheses of the highly functionalized polysubstituted δ‐lactones 33–39, the reactivity of which has been studied.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

Vinyl Epoxides in Organic Synthesis

“…Under palladium catalysis, 859 reacted to yield the πallylpalladium species 860, and rapid silyl migration ensued to generate 861 in high yield (Scheme 318). 313 This reaction occurred for disubstituted alkenes, even if the alkene were cis to the bulky silyl group. Spirolactone 862 underwent the same rearrangement to afford aldehyde 863 in excellent yield (Scheme 319).…”

Synthesis of 1,2-Dihydropyridines Using Vinyloxiranes as Masked Dienolates in Imino-Aldol Reactions

“…Vinyloxiranes are valuable building blocks for a variety of synthetic transformations and have found wide applications in organic synthesis . In particular, transition metal and Lewis acid catalyzed ring opening of the epoxides, with subsequent rearrangement, gives access to useful products for the synthesis of biologically active compounds. , Recently, our group reported the amphoteric character of 2-vinyloxiranes in the presence of a Lewis acid 4a. The 2-vinyloxiranes are either used as synthetic equivalents for β,γ-unsaturated aldehydes (electrophiles) or dienols (nucleophiles).…”

Synthetic Approaches to α,β‐Unsaturated δ‐Lactones and Lactols

“…After completion of the rearrangement (TLC monitoring), alkylation of the aldehyde with a Grignard reagent proceeds with a complete anti diastereoselectivity, thus providing (when starting from enantiomerically pure silylated vinylepoxides) enantiomerically pure γ-silylated lactones. The desilylation process (KF/DMSO), however, occurred with partial racemization [58] (Scheme 25).…”