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Updated: Jul 15, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Synthesis of (±)-Angustatin A: Assembly of the Phenanthrene Moiety Despite Increasing Ring Strain
Hoang D Doan1, Christian Rugen1, Christopher Golz1
1Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen, 37077 Göttingen, Germany.
Abstract:
The synthesis of (±)-angustatin A, a phenanthrene-containing cyclophane that possesses conformational chirality, is reported. Key steps include a Pd-catalyzed Negishi coupling to assemble the necessary terphenyl intermediate, its closure into a 14-membered macrocycle via a catalytic-in-phosphine Wittig olefination, and finally a Pt-catalyzed alkyne hydroarylation, which is able to assemble the phenanthrene unit despite the thermodynamic cost of significantly bending arene A from the ideal plane.
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