3,3'-disubstituted BINAP ligands: synthesis, resolution, and applications in asymmetric hydrogenation.
A novel family of BINAP ligands were prepared with alkoxy- and acetoxy-derived substituents in the 3,3'-positions. They were prepared through a convergent synthesis starting from readily available 4-bromo-2-naphthol. These ligands afforded excellent enantioselectivities in the asymmetric hydrogenation of substituted olefins. The presence of the 3,3'-substituents was shown to be beneficial by a direct comparison with the parent unsubstituted BINAP. [reaction: see text]
Hopkins
J Matthew
JM
Department of Chemistry, University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada.
Dalrymple
Sean A
SA
Parvez
Masood
M
Keay
Brian A
BA