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Updated: Jun 5, 2025

Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
Temperature-Dependent Diastereodivergent [4 + 3] Annulation: Synthesis of Ferrocene-Fused Azepines via Rh(III)
Raviraj Ananda Thorat1, Devendra Parganiha1, Saket Jain1
1Department of Chemistry, Indian Institute of Science Education and Research (IISER) Bhopal, Bhopal By-Pass Road, Bhopal, Madhya Pradesh 462066, India.
Abstract:
Herein, we disclose the first temperature-dependent diastereodivergent [4 + 3] annulation of ferrocene-p-tosylamides via C-H activation with allenes by a Rh catalyst. At room temperature, Rh-catalyzed [4 + 3] annulation selectively offered a kinetically controlled diastereomer [>20:1 diastereomeric ratio (dr)], whereas at 60 °C, a thermodynamically controlled diastereomer was obtained exclusively with >20:1 dr.
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