Busacca Carl A, Lorenz Jon C, Grinberg Nelu, Haddad Nizar, Lee Heewon, Li Zhibin, Liang Mary, Reeves Diana, Saha Anjan, Varsolona Rich, Senanayake Chris H
Department of Chemical Development, Boehringer-Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, Connecticut 06877, USA.
Org Lett. 2008 Jan 17;10(2):341-4. doi: 10.1021/ol7028542. Epub 2007 Dec 21.
Asymmetric hydrogenation of unsaturated urea esters with the BIPI Ligands has been examined. Optimization of the P-N ligand 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 important new ligands for catalysis of asymmetric hydrogenation has been developed.
已对使用BIPI配体进行不饱和脲酯的不对称氢化反应进行了研究。对P-N配体结构的优化已导致开发出能够以>99%的对映体过量（ee）生产目标产物的手性铑催化剂。配体合成所需的关键膦硼烷亲核芳香取代反应（SNAr）已得到优化，可在室温下高产率地得到加合物且无消旋化。已开发出一种极其简洁、经济且可扩展的方法来合成这些用于催化不对称氢化的重要新配体。
