Asymmetric [2+2] photocycloaddition via charge transfer complex for the synthesis of tricyclic chiral ethers
Ana M Martínez-Gualda1, Pablo Domingo-Legarda, Thomas Rigotti
1Organic Chemistry Department, Universidad Autónoma de Madrid, Madrid 28049, Spain. jose.aleman@uam.es.
Abstract:
The asymmetric synthesis of chiral polycyclic ethers by an intramolecular [2+2] photocycloaddition is described. This process proceeded through a photocatalytically active iminium ion-based charge transfer (CT) complex under visible light irradiation. In this way a stereocontrolled [2+2] photocycloaddition is enabled leading to tricyclic products with good enantiomeric ratios.
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