Remote aromatic metalation. An anionic Friedel-Crafts equivalent for the regioselective synthesis of condensed fluorenones from biaryl and m-teraryl 2-amides
摘要:
Remote metalation (t-BuLi, LDA) of m-teraryl and biaryl amides (Scheme I) constitutes a short and convenient route to a variety of substituted and condensed fluorenones, including aza analogues (Table I) and the natural product, dengibsinin (6a, Scheme II).
Directed MetalationCross-Coupling Strategies. Total Syntheses of the Alleged and the Revised Phenanthrene Natural Product Gymnopusin
作者:Xin Wang、Jian-min Fu、Victor Snieckus
DOI:10.1002/hlca.201200564
日期:2012.12
The totalsynthesis of gymnopusin (2) is described. The originally assigned structure for gymnopusin 1a was found to be incorrect by totalsynthesisusing the Directed ortho‐Metalation (DoM)Cross‐CouplingDirected remote Metalation (DreM) sequence, a demonstrable key strategy for the regioselective construction of the 9‐phenanthrol core. The revised structure of gymnopusin (2) was confirmed by synthesis
描述了裸子肌动蛋白(2)的总合成。使用定向邻位金属化(D o M)交叉偶联定向远距离金属化(DreM)序列进行全合成发现,最初为裸藻蛋白1a分配的结构是不正确的,这是9的区域选择性构建的可证明的关键策略菲酚核心。通过采用相同策略但涉及关键的远程阴离子Fries合成方法,通过合成确认了裸藻蛋白(2)的修订结构。重排步骤。两种途径都强调了方法学和概念,这些方法学和概念可能对具体的菲咯啉类的区域控制合成以及通常在复杂的多环芳族化合物中有价值。