Ligand-Enabled Sequential C(sp(3))-H and C(sp(2))-H Diolefination Reaction via Palladium Catalyst

Palladium-catalyzed sequential C(sp(3))-H and C(sp(2))-H bond diolefination reaction of o-toluidine has been realized for the first time using acetyl-protected aminoethyl phenyl thioether ligands. This novel reaction allows for preparation of the conjugated diene structure via an immediate second olefination on the basis of the first C(sp(3))-H olefination in one pot. Various triflyl-protected anilines and acrylates were used as coupling partners elegantly. Furthermore, the unpurified diolefination products can be easily converted to tetrahydroquinoline derivatives.