Phosphinoferrocenylaminophosphines as novel and practical ligands for asymmetric catalysis.
[structure: see text] A new series of ligands with a novel phosphine-aminophosphine ligation design as depicted in structure 1 has been prepared on a ferrocenylethyl backbone. These BoPhoz ligands of structure 2 have afforded exceedingly high activity and enantioselectivity in the rhodium-catalyzed asymmetric hydrogenation of dehydro-alpha-amino acid derivatives, itaconic acids, and alpha-ketoesters. These air-stable ligands are readily prepared from cost-effective and non-pyrophoric intermediates.
Boaz
Neil W
NW
Research Laboratories, Eastman Chemical Company, P.O. Box 1972, Kingsport, Tennessee 37662, USA. nwboaz@eastman.com
Debenham
Sheryl D
SD
Mackenzie
Elaine B
EB
Large
Shannon E
SE