Selectively Tunable Synthesis of α-Trifluoromethyl Ketones.

A cross-coupling of aldehydes and α-trifluoromethyl alkyl bromides was developed via dual nickel/photoredox catalysis system. A wide variety of substrates bearing a diverse set of functional groups were compatible to afford α-trifluoromethyl ketones under very mild conditions (visible light, ambient temperature, no strong base). Selectively tunable access to these ketones with the trifluoromethyl group on any one side can be smoothly obtained by simply modulating different reagents. Meanwhile, the asymmetric pattern was also investigated.