Synthesis of chiral fluorine-containing compounds via Pd-catalyzed asymmetrical allylations of dimethyl 2-fluoromalonate using sulfonamide-pyridine ligands

• A set of new chiral sulfonamide-pyridine ligands has been synthesized from a new chiral sulfoxide.
• The Pd/sulfonamide-pyridine ligand catalyst provided the monofluorinated allylic products with high ee.
• The sulfonamide moiety on the ligand has a significant effect on the enantiocontrol.

Chiral o-aniline sulfoxides serving as chiral sulfurous source were synthesized, from which new sulfonamide-pyridine ligands were made in three-steps. These compounds proved to be efficient S,N-ligands for enantiocontrol of palladium-catalyzed allylic substitutions of dimethyl 2-fluoromalonate. The induced effect of the Pd/S,N-ligand catalyst on the enantioselectivity depends on the steric demand of the substituent on the sulfoxide moiety. This method provided the fluorine-containing allylic products with up to 94% ee.