Copper-catalyzed asymmetric hydrogenation of 2-substituted ketones via dynamic kinetic resolution
Olga V Zatolochnaya1, Sonia Rodríguez1, Yongda Zhang1
1Chemical Development , Boehringer Ingelheim Pharmaceuticals, Inc. , 900 Old Ridgebury Road , Ridgefield , CT 06877 , USA . Email: yongda.zhang@boehringer-ingelheim.com ;
Abstract:
A new class of tunable heterophosphole dimeric ligands have been designed and synthesized. These ligands have enabled the first examples of Cu-catalyzed hydrogenation of 2-substituted-1-tetralones and related heteroaryl ketones via dynamic kinetic resolution, simultaneously creating two contiguous stereogenic centers with up to >99 : 1 dr and 98 : 2 er. The ligand-Cu complexes were isolated and characterized by single crystal X-ray, and DFT calculations revealed a novel heteroligated dimeric copper hydride transition state.
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