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Updated: Jan 18, 2026

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Catalytic Asymmetric (ene-endo)-Carbonyl-Ene Type Cyclizations
Lixia Shi1, Nobuya Tsuji2, Chendan Zhu1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Mülheim an der Ruhr, Germany.
None:
The carbonyl-ene reaction between aldehydes and olefins constitutes a perfectly atom economic approach to homoallylic alcohols with concomitant C-C bond formation. However, the scope of catalytic asymmetric intermolecular versions is currently limited to activated substrates, while of the two intramolecular types only catalytic asymmetric (ene-exo)-carbonyl-ene type cyclizations can be considered mature. The corresponding (ene-endo)-cyclizations would arguably find equal utility in chemical synthesis but remain underdeveloped. Herein, we report an efficient regio- and enantioselective catalytic asymmetric (ene-endo)-carbonyl-ene type cyclization of unbiased alkenyl aldehydes using a strong and confined IDPi Brønsted acid catalyst. High enantioselectivities of up to 98:2 e.r. were obtained for a range of homoallylic alcohols.
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