of formation of the corresponding salts or the addition of any additive has been
reported using Ir/(R)-BTFM-Garphos catalyst (ees up to 96%, Fig. 39) [252]. A
highly enantioselective hydrogenation of heteroaromatics bearing a hydroxyl group,
3-hydroxypyridinium salts, has been successfully developed using Ir/(S,S)-fbinaphane catalyst, providing a direct access to trans 6-substituted piperidin-3-ols
Fig. 38 Iridium-catalyzed enantioselective hydrogenation of cyclic imines using Ir/(R)-SynPhos
catalyst
Fig. 39 Representative examples of iminium salts successfully hydrogenated
188
J. Margalef et al.