Department of Chemistry, Yale University , 225 Prospect Street, New Haven, Connecticut 06520-8107, United States.
J Am Chem Soc. 2018 Feb 14;140(6):2062-2066. doi: 10.1021/jacs.7b13189. Epub 2018 Feb 5.
We report a total synthesis of the pyridine-containing limonoid alkaloid (-)-xylogranatopyridine B in 11 steps from commercially available dihydrocarvone. The central pyridine ring was assembled by a late-stage fragment coupling approach employing a modified Liebeskind pyridine synthesis. One fragment was prepared by an allyl-palladium catalyzed oxidative enone β-stannylation, in which the key bimetallic β-stannyl palladium enolate intermediate undergoes a β-hydride elimination. This methodology also allowed introduction of alkyl and silyl groups to the β-position of enones.
我们报道了从商业可得的二氢大马酮出发，经 11 步反应全合成含吡啶的柠檬苦素生物碱（-）-木菠萝酮 B。通过晚期的片段偶联方法，使用改良的 Liebeskind 吡啶合成，组装了中心吡啶环。一个片段通过烯丙基钯催化的氧化烯酮β-锡化反应制备，其中关键的双金属β-锡基钯烯醇化物中间体经历β-氢消除。这种方法还允许将烷基和硅烷基引入到烯酮的β-位。
