Affiliation:
1. Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular Engineering School of Chemistry and Molecular Engineering East China Normal University Shanghai 200062 China
2. Department of Chemistry Fudan University 2005 Songhu Road Shanghai 200438 China
Abstract
AbstractCentral chirality is an important chiral element used in the design of chiral ligands and catalysts. Mostly, the attention of organic chemists is focused on developing of chiral ligands with stable stereogenic centers. However, the N‐chirality in chiral ligand design has been rarely explored due to its flexibility. Here we demonstrate the design, synthesis, and application of a class of simple P,N‐ligands with flexible N‐chirality and their derived iridium complexes with fixed N‐chiral stereocenters. Both fixed configurations of the N‐stereocenter of the iridium complexes could be selectively formed from the same chiral ligand. This pair of diastereoisomeric iridium complexes showed good performance in the enantiodivergent asymmetric hydrogenation of exocyclic α,β‐unsaturated lactams. The N−H group plays an impressive role in catalytic activity. Computational studies emphasized the importance of N‐chirality and N−H group.
Funder
National Natural Science Foundation of China