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Updated: Feb 13, 2026

Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
Allenylic Carbonates in Enantioselective Iridium-Catalyzed Alkylations
David A Petrone1, Mayuko Isomura1, Ivan Franzoni2
1ETH Zürich , Vladimir-Prelog-Weg 3, HCI , 8093 Zürich , Switzerland.
Abstract:
An enantioconvergent C(sp3)-C(sp3) coupling between racemic allenylic electrophiles and alkylzinc reagents has been developed. An Ir/(phosphoramidite,olefin) catalyst provides access to highly enantioenriched allenylic substitution products (93-99% ee) with complete regiocontrol (>50:1 rr in all cases) over the corresponding 1,3-diene isomers which are obtained predominantly when other metal catalysts are emplyed. The synthetic utility of the products obtained was highlighted in a variety of stereoselective transition metal-catalyzed difunctionalization reactions. Furthermore, a combination of experimental and theoretical studies provide support for a putative reaction mechanism wherein enantiodetermining C-C coupling occurs via nucleophilic attack on a highly planarized aryl butadienylium π-system that is coordinated to the Ir center in an η2-fashion.
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