Eosin, blue LEDs and DIPEA are employed in a simple synthesis of (poly)cyclic O,O- and N,O-acetals
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Updated: Jun 27, 2025

Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Ioannis Papadopoulos1, Artemis Bosveli1, Tamsyn Montagnon1
1Department of Chemistry, University of Crete, Vasilika Vouton, 71003, Iraklion, Crete, Greece. vasil@uoc.gr.
Abstract:
A simple procedure for the synthesis of (poly)cyclic O,O- and N,O-acetals from various enol ethers, N-acyl enamines or Boc-protected enamines has been developed. The key step is a photocatalytic Stork-Ueno-type cylization using the very simple metal-free conditions of catalytic eosin, diisopropylamine in the green solvent ethanol with blue LED irradition.
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