ABSTRACT
Palladium(II)-catalyzed meta-selective C-H allylation of arenes has been developed utilizing synthetically inert unactivated acyclic internal olefins as allylic surrogates. The strong σ-donating and π-accepting ability of pyrimidine-based directing group facilitates the olefin insertion by overcoming inertness of the typical unactivated internal olefins. Exclusive allyl over styrenyl product selectivity as well as Eâ stereoselectivity were achieved with broad substrate scope, wide functional-group tolerance, and good to excellent yields. Late-stage functionalisations of pharmaceuticals were demonstrated. Experimental and computational studies shed light on the mechanism and point to key steric control in the palladacycle, thus determining product selectivities.
