Partially carbonized chiral polymer with Cu-bis(oxazoline) as an efficient heterogeneous catalyst for asymmetric Henry reaction†
Abstract
Herein, we report the design and synthesis of a novel chiral heterogeneous catalyst by condensation polymerization of 1,4-phthalaldehyde and amine-containing chiral bis(oxazoline) ligands, followed by partial carbonization and coordination with copper. The catalyst exhibited high activity, superior enantioselectivity (even better than the homogeneous catalyst) and outstanding recyclability in heterogeneous asymmetric Henry reaction.