Nickel-Catalyzed 1,2-Diarylation of Alkenyl Ketones: A Comparative Study of Carbonyl-Directed Reaction Systems
A conjunctive cross-coupling reaction of alkenyl ketones, aryl iodides, and arylboronic esters under nickel catalysis is reported. The reaction delivers the desired 1,2-diarylated products with moderate to excellent regiocontrol using a diverse array of ketone starting materials, as illustrated across over 40 examples. To showcase the versatility of this method, a representative product is diversified into a wide range of synthetically useful building blocks, that are not readily accessible via existing 1,2-diarylation reactions. Preliminary mechanistic studies shed light on the binding mode of the substrate, and Hammett analysis shows the effect of electronic factors on initial rates. To our knowledge, this method represents the first example of catalytic 1,2-diarylation of an alkene, directed by a native ketone functional group.