Amines with free N–H groups have long posed a tremendous challenge in transition metal-catalysed amination reactions. Now, use of a bidentate phosphorus ligand enables the palladium-catalysed oxidative amination of simple olefins with Lewis basic amines, with no prefunctionalization, forming both alkyl and aryl allylamines.

Now, writing in Nature Chemistry, Huanfeng Jiang and co-workers have developed a catalyst-controlled solution to prevent poisoning by Lewis basic nitrogen atoms in the oxidative amination of terminal alkenes3. Bidentate phosphine ligands were proposed as having a dual function — inhibiting the deactivation of the palladium catalyst and accelerating the C–H bond activation to enable the oxidative amination of terminal olefins. The novel system uses Pd(OAc)2, 1,3-diphenylphosphinopropane (DPPP), and 2,6-dimethyl-1,4-benzoquinone (2,6-DMBQ), and was proposed to proceed through an allylic C–H bond activation, followed by isomerization of the resulting η1-σ-Pd(allyl) complex to an η3-π-Pd(allyl) complex. The amine then attacks the palladium complex and is subsequently deprotonated to form the allylamine products.