1809609-53-7Relevant articles and documents
Development of Chiral Spiro P-N-S Ligands for Iridium-Catalyzed Asymmetric Hydrogenation of β-Alkyl-β-Ketoesters
Bao, Deng-Hui,Wu, Hui-Ling,Liu, Chao-Lun,Xie, Jian-Hua,Zhou, Qi-Lin
supporting information, p. 8791 - 8794 (2015/11/27)
The chiral tridentate spiro P-N-S ligands (SpiroSAP) were developed, and their iridium complexes were prepared. Introduction of a 1,3-dithiane moiety into the ligand resulted in a highly efficient chiral iridium catalyst for asymmetric hydrogenation of β-alkyl-β-ketoesters, producing chiral β-alkyl-β-hydroxyesters with excellent enantioselectivities (95-99.9 % ee) and turnover numbers of up to 355 000. Bulkyness is the key: New chiral tridentate spiro P-N-S ligands (SpiroSAP) bearing a conformationally constrained 1,3-dithiane moiety were developed. Their iridium catalysts showed excellent enantioselectivities and activity (TON up to 355 000) for asymmetric hydrogenation of β-alkyl-β-ketoesters.