An efficient and broadly applicable process is reported for the direct alkylation of heteroarene C–H bonds, based on the copper-catalyzed addition of alkyl radicals generated from activated secondary and tertiary alkyl bromides to a range of arenes, and their benzo-fused derivatives.
A palladium catalyst in combination with two types of phosphine ligands efficiently catalyzes direct C–H alkylation of heteroarenes with secondary and tertiary alkyl bromides under irradiation conditions. Irradiation of blue light-emitting diodes (blue LEDs) effectively excites phosphine-ligated palladium catalyst to facilitate oxidative addition with alkyl bromides, and also excites the alkylpalladium species to enable the generation of alkyl radicals to react with heteroarenes.
Copper-catalyzed direct alkylation of heteroarenes
