New chiral amine ligands in the desymmetrization of prochiral phosphine boranes
Artikel i vetenskaplig tidskrift, 2004

P-chirogenic phosphine ligands can be prepared via desymmetrization of prochiral phosphine boranes using s-BuLi.(-)-sparteine complexes. One limitation of this method, however, has been that (+)-sparteine is not easily accessible. Herein, we show that derivatives of another alkaloid, (-)-cytisine, are useful surrogates for (+)-sparteine in the desymmetrization of prochiral phenyl-, cyclohexyl- and tert-butyl dimethyl phosphine boranes, yielding chiral phosphine boranes in up to 92% ee. Other chiral diamines were also tested but did not give as high enantioselectivity as the (-)-cytisine derivatives.

(-)-CYTISINE

DIPHOSPHINE LIGANDS

ASYMMETRIC-SYNTHESIS

DIAMINES

Författare

M. J. Johansson

Göteborgs universitet

Lennart Schwartz

Chalmers University of Technology

Mohamed Amedjkouh

Göteborgs universitet

Nina Kann

Chalmers, Institutionen för kemi och biovetenskap

Tetrahedron Asymmetry

0957-4166 (ISSN) 1362-511X (eISSN)

Vol. 15 3531-3538

Ämneskategorier

Kemi

DOI

10.1016/j.tetasy.2004.09.023