Chiral organometallic complexes were immobilized in silica supported thin films of ionic liquid. The heterogenized catalysts were tested in the hydrogenation of acetophenone, which was chosen as test reaction for the enantioselective reduction of prochiral ketones. High enantioselectivities (up to 74% ee) were achieved in supported ionic liquids using a catalyst/substrate pair, which showed no enantioselectivity in methanol. This is attributed to the unique solvent properties of ionic liquids including the formation of solvent cages of ionic liquid molecules around the complexes. Within these cages, transition states are modified and chemical transformations follow alternative reaction pathways.
- Ionic liquid
- Two-phase catalysis
ASJC Scopus subject areas
- Process Chemistry and Technology
- Physical and Theoretical Chemistry