Organophotoredox-Catalyzed Intermolecular Formal Grob Fragmentation of Cyclic Alcohols with Activated Allylic Acetates.

We have developed an efficient method that employs organophotoredox-catalyzed relay Grob fragmentation to facilitate the smooth ring-opening allylation of cyclic alcohols in an environmentally friendly manner. This protocol directly incorporates a wide spectrum of cyclic alcohols and activated allylic acetates into the cross-coupling reaction, eliminating the need for metal catalysts. The process yields a variety of distally unsaturated ketones with good to excellent outcomes and stereoselectivity, while acetic acid is the sole byproduct.

Visible-Light-Induced Trifluoromethylation of Allylic Alcohols.

An organic photoredox-catalyzed dehydroxylative trifluoromethylation of allylic alcohols was developed in an environmentally benign manner. In this reaction, the readily available CF3SO2Na was selected as the trifluoromethylation reagent. The in situ generated byproduct SO2 was reutilized to activate C-OH bond, which enabled this dehydroxylative trifluoromethylation to be performed conveniently. A variety of multifunctionalized CF3-allylic compounds were obtained in high yields and excellent stereoselectivity.