Ir-catalysed asymmetric hydrogenation: Ligands, substrates and mechanism.
Relatively air and moisture tolerant cationic iridium complexes, with chiral non-racemic N,P-ligands and weakly coordinating counter ions, are efficient catalysts in the asymmetric hydrogenation of olefins. Unfunctionalised olefins are particularly difficult substrates because, in general, a polar group adjacent to the alkene bond is required for high catalytic activity and enantioselectivity. The applicability towards a variety of substrates and choice of ligands reported thus far in the literature, as well as the mechanism, selectivity issues and the importance of the anion are also discussed.
Källström
Klas
K
Uppsala Universitet, Avd. f. Organisk Kemi, Kemiska Institutionen, Box 559, 751 24 Uppsala, Sweden.
Munslow
Ian
I
Andersson
Pher G
PG