Asymmetric Hydrogenation of Unsaturated Ureas with the BIPI Ligands
作者:Carl A. Busacca、Jon C. Lorenz、Nelu Grinberg、Nizar Haddad、Heewon Lee、Zhibin Li、Mary Liang、Diana Reeves、Anjan Saha、Rich Varsolona、Chris H. Senanayake
DOI:10.1021/ol7028542
日期:2008.1.1
structure has led to the development of chiral rhodium catalysts capable of producing the targets with >99% ee. The critical phosphine borane SNAr reaction needed for ligand synthesis has been optimized to give the adducts in high yield at ambient temperature with no racemization. An extremely concise, economical, and scalable sequence to these importantnew ligands for catalysis of asymmetric hydrogenation