Photocatalyzed Cascade Reactions of Cyclopropanols and α-Trifluoromethyl-Substituted Olefins for the Synthesis of Fused gem-Difluorooxetanes

Fluorinated fused rings are challenging to construct from simple starting materials. Herein, we report the first photocatalyzed cascade reactions of readily available cyclopropanols and alpha-trifluoromethyl-substituted olefins for the synthesis of fused gem-difluorooxetanes. Two rings and three bonds were efficiently constructed in one reaction. The reaction showed broad substrate scope and the downstream transformations of the products demonstrated the synthetic potential of the reaction. The mechanistic study supported the presence of cascade photoredox catalysis and energy transfer catalysis/direct photo-excitation processes.

Automated summary

In this study, photocatalyzed cascade reactions between readily available cyclopropanols and alpha-trifluoromethyl-substituted olefins were reported for the synthesis of fused gem-difluorooxetanes. Two rings and three bonds were efficiently constructed in one reaction. The reaction demonstrated broad substrate scope and the downstream transformations of the products highlighted the synthetic potential. Mechanistic study supported the presence of cascade photoredox catalysis and energy transfer catalysis/direct photo-excitation processes.