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Updated: Oct 29, 2025

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Published on: August 16, 2018
Catalytic (3 + 2) annulation of donor-acceptor aminocyclopropane monoesters and indoles
Vincent Pirenne1, Emma G L Robert1, Jerome Waser1
1Laboratory of Catalysis and Organic Synthesis, Institut des Sciences et Ingénierie Chimique, Ecole Polytechnique Fédérale de Lausanne Ch-1015 Lausanne Switzerland jerome.waser@epfl.ch.
Abstract:
The efficient catalytic activation of donor-acceptor aminocyclopropanes lacking the commonly used diester acceptor is reported here in a (3 + 2) dearomative annulation with indoles. Bench-stable tosyl-protected aminocyclopropyl esters were converted into cycloadducts in 46-95% yields and up to 95 : 5 diastereomeric ratio using catalytic amounts of triethylsilyl triflimide. Tricyclic indoline frameworks containing four stereogenic centers including all-carbon quaternary centers were obtained.
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