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Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
Reagent- and Ligand-Dependent Mechanistic Trichotomy in Fe-Catalyzed Borylative Cyclizations of Enynes
Fabian Rami1, Benedict Klinnert2, Jan Nowak1
1Institut für Organische Chemie, Fakultät Chemie, Universität Stuttgart, Pfaffenwaldring 55, DE-70569 Stuttgart, Germany.
Abstract:
Based on some very recent results on Fe-catalyzed boron-source-dependent regiodivergent hydroborations of internal alkynes, we report here a boron-source-dependent but also ligand-dependent mechanistic trichotomy in borylative cyclizations. The choice of ligand plus boron source allows the synthesis of three isomeric borylative cyclization products starting from a common substrate and using the same precatalyst ((Ph3P)2Fe(CO)(NO)H) and sets the stage for the development of a unifying concept in Fe-catalyzed borylative cyclizations.
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