Desymmetrization of prochiral phosphanes using derivatives of (-)-cytisine
Journal article, 2004
yHistorically, (-)-sparteine-sec-BuLi has been used to desym-metrize prochiral phosphanes. In this report, derivatives of an alkaloid extracted from the seeds of Laburnum anagyro-ides have been utilized to mimic (+)-sparteine, which is not readily available. In several cases, the enantioselectivities achieved with the (+)-Sparteine surrogates outperformed (-)-sparteine itself in the deprotonation of alkyl-substituted (as well as aryl-substituted) prochiral phosphane derivatives. In addition, use of these surrogates allows a new methodology for a chiral switch in phosphorus chemistry. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).
LIGANDS
lithiation
enantioselectivity
PHOSPHINE BORANES
sparteine
CATALYZED ASYMMETRIC HYDROGENATION
ENANTIOSELECTIVE HYDROGENATION
STRATEGY
asymmetric synthesis
P-CHIRAL DIPHOSPHINES
PHOSPHORUS
phosphanes
Author
M. J. Johansson
University of Gothenburg
Lennart Schwartz
Chalmers
Mohamed Amedjkouh
University of Gothenburg
Nina Kann
Chalmers, Department of Chemistry and Bioscience
European Journal of Organic Chemistry
1434-193X (ISSN) 10990690 (eISSN)
9 1894-1896Subject Categories
Chemical Sciences
DOI
10.1002/ejoc.200400006