Assembly of Tetrahydroquinolines and 2-Benzazepines by Pd-Catalyzed Cycloadditions Involving the Activation of C(sp³)–H Bonds

Cycloaddition reactions are among the most practical strategies to assemble cyclic products; however, they usually require presence of reactive functional groups in reactants. Here, we report a palladium-catalyzed formal (4 + 2) cycloaddition that involves activation C(sp3)–H bonds and provides direct, unconventional entry tetrahydroquinoline skeletons. The reaction utilizes amidotolyl precursors allenes as annulation partners, is catalyzed by Pd(II) combination with specific N-acetylated amino acid ligands. reactivity can be extended ortho-methyl benzylamides, which provide for assembly appealing tetrahydro-2-benzazepines (5 process.