Asymmetric Diels-Alder Reaction Using a Polymer-Supported N-P Type Ligand
H. Nakano*, K. Takahashi, R. Fujita
Tohoku Pharmaceutical University, Japan
21. September 2005 (online)
A cationic palladium complex of a polystyrene-ethyl (PS-Et)-supported chiral phosphinooxazoline ligand provided excellent enantioselectivity (92% ee) in the asymmetric Diels-Alder reaction of cyclopentadiene (2) with acryloyl-1,3-oxazolidine-2-one (3). The polymeric catalyst 1 was recycled with approximately 30% loss in both activity (from 79% to 45% yield) and enantioselectivity (from 92% to 62% ee).