Scientific article
Open access

Primary Anion–π Catalysis of Epoxide‐Opening Ether Cyclization into Rings of Different Sizes: Access to New Reactivity

Published inAngewandte Chemie: International Edition, vol. 59, no. 15, p. 6273-6277
Publication date2020

The concept of anion–π catalysis focuses on the stabilization of anionic transition states on aromatic π surfaces. Recently, we demonstrated the occurrence of epoxide‐opening ether cyclizations on aromatic π surfaces. Although the reaction proceeded through unconventional mechanisms, the obtained products are the same as those from conventional Brønsted acid catalysis, and in agreement with the Baldwin selectivity rules. Different mechanisms, however, should ultimately lead to new products, a promise anion–π catalysis has been reluctant to live up to. Herein, we report non‐trivial reactions that work with anion–π catalysis, but not with Brønsted acids, under comparable conditions. Namely, we show that the anion–π templated autocatalysis and epoxide opening with alcoholate–π interactions can provide access to unconventional ring chemistry. For smaller rings, anion–π catalysis affords anti‐Baldwin oxolanes, 2‐oxabicyclo[3.3.0]octanes, and the expansion of Baldwin oxetanes by methyl migration. For larger rings, anion–π templated autocatalysis is thought to alleviate the entropic penalty of folding to enable disfavored anti‐Baldwin cyclizations into oxepanes and oxocanes.

Research group
Citation (ISO format)
PARAJA, Miguel, MATILE, Stefan. Primary Anion–π Catalysis of Epoxide‐Opening Ether Cyclization into Rings of Different Sizes: Access to New Reactivity. In: Angewandte Chemie: International Edition, 2020, vol. 59, n° 15, p. 6273–6277. doi: 10.1002/anie.202000579
Main files (2)
Article (Published version)
Article (Accepted version)
ISSN of the journal1433-7851

Technical informations

Creation04/02/2020 3:30:00 PM
First validation04/02/2020 3:30:00 PM
Update time03/15/2023 9:27:50 PM
Status update03/15/2023 9:27:49 PM
Last indexation01/17/2024 9:33:21 AM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack