Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA.
Org Lett. 2011 Oct 7;13(19):5136-9. doi: 10.1021/ol202002r. Epub 2011 Aug 31.
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.
三组分偶联反应将 t-BuOAc 的锂烯醇盐、硅基乙二醛酸酯和α,β-不饱和酮结合在一起,从而快速构建了 Trachyspic 酸的碳骨架。利用 3,4-二取代异恶唑来掩蔽 C7/C9 二羰基。新的烯基硅烷/硝酮环加成反应可以制备各种 3,4-二取代异恶唑,这些异恶唑用其他方法难以获得。