An enantioselective Mannich-type reaction of in situ generated cyclic ketimines with
difluoroenoxysilanes catalyzed by chiral spirocyclic phosphoric acid has been developed.
This methodology provides a facile route to difluoroalkyl-substituted chiral isoindolinones
bearing a quaternary stereogenic center in high yields and up to 96% enantioselectivity.
Key words
enantioselective synthesis - Mannich-type reaction - chiral spirocyclic phosphoric
acid - isoindolinone - difluoroenoxysilane