Application of P-stereogenic aminophosphine phosphinite ligands in asymmetric hydroformylation |
| |
Authors: | Ewalds Eggeling Hewat Kamer van Leeuwen PW Vogt |
| |
Institution: | Ciba, Division Additives AD 4.21, WS 2093.3.15, Pratteln 1, Switzerland. |
| |
Abstract: | New chiral aminophosphine phosphinite ligands with a stereogenic center at the aminophosphine phosphorus atom were prepared based on (R,S)-ephedrine as the chiral auxiliary and backbone. Substituents at the chiral aminophosphine as well as at the phosphinite phosphorus atom were varied. These new ligands were applied to the rhodium-catalyzed asymmetric hydroformylation of vinyl arenes. The enantiomeric excess reached up to 77%. 1H and 31P NMR studies of the Rh complexes under syngas pressure reveal that HRh(CO)2(PP)] complexes with the NP* moiety in an axial position are responsible for enantioselectivity. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
|