SilverCatalyzed Cascade Carboxylation and Cyclization of Trimethyl(2-methylenebut-3-yn-1-yl)silane Derivatives
摘要:
C-C bond forming carboxylation, and cyclization: of trimethyl(2-rnethylenbut-3,7yl)silaile derivatives and carbon dioxide was developed. Silver catalysts and CsF promoted the reaction to afford the:corresponding 2-furanone and 2-pyrone derivatives in good-to-high yields. The structure of the 2:furanone was confirmed by single-crystal X-ray crystallography, which revealed that the geometry of the exo-olefin was that of a Z-isomer. When an aromatic ring substituted alkyne was used, 2-furanone derivatives were selectively obtained via 5-exo-dig-cyclization, whereas the reaction of alkyl-substituted alkynes produced 2-pyrone derivatives with high selectivity.