An efficient and convenient cobalt(III)‐catalyzed highly diastereoselective strategy was demonstrated for the synthesis of epoxybenzophenanthridinone derivatives. The sp² C−H activation of N‐methoxybenzamides and their annulation reaction with 7‐oxa/aza benzonorbornadienes proceeds under mild conditions and exhibits excellent functional group tolerance. In addition, the products were transformed to biologically relevant phenanthridinones by an acid‐catalyzed ring opening/aromatization sequence.

中文翻译：

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钴（III）催化sp2 CH活化的杂环双烯环[4 + 2]

证明了一种有效且方便的钴（III）催化的高度非对映选择性策略可用于合成环氧苯并菲蒽酮衍生物。N-甲氧基苯甲酰胺的sp ² C H活化及其与7-氧杂/氮杂苯并降冰片二烯的环化反应在温和的条件下进行，并表现出出色的官能团耐受性。此外，通过酸催化的开环/芳构化序列，将产物转化为生物学上相关的菲啶酮。