Catalytic Enantioselective Double Carbopalladation/C-H Functionalization with Statistical Amplification of Product Enantiopurity: A Convertible Linker Approach.

Combining a catalytic enantioselective reaction with dimerization in a single operation is an efficient way to upgrade the enantiomeric excesses (ee) of the product. Palladium-catalyzed reaction of N-(2-iodophenyl)-N-methyl methacrylamide derivatives with oxadiazole afforded, by a double enantioselective carbopalladation/intermolecular heteroarene C-H alkylation sequence, homodimers in good yields with excellent ee values. The dimer was subsequently elaborated to the monomer in which the linker (oxadiazole) was incorporated into the target product.

Synthesis of enantioenriched 5,6-dihydrophenanthridine derivatives through retro-carbopalladation of chiral o-bromobenzylamines.

Retro-carbopalladation of aldimines in the presence of a suitable β-hydrogen atom has been observed in the Pd-catalyzed homocoupling reactions of o-bromobenzylamines, providing an expeditious synthetic route to 5,6-dihydrophenanthridine derivatives. Furthermore, a highly enantioselective synthesis of 6-aryl-substituted 5,6-dihydrophenanthridines was achieved in a one-pot manner by taking advantage of Rh and Pd catalysis.