Three-Component Coupling Approach to Trachyspic Acid

Three-component coupling of the lithium enolate of t-BuOAc, silyl glyoxylate, and an α,β-unsaturated ketone enables the rapid construction of the trachyspic acid carbon skeleton. A 3,4-disubstituted isoxazole is utilized to mask the C7/C9 dicarbonyl. New enolsilane/nitrile-oxide cycloadditions enable the preparation of various 3,4-disubstituted isoxazoles that are challenging to access by other means.