Asymmetric Hydrogenation of 2,4-Disubstituted 1,5-Benzodiazepines Using Cationic Ruthenium Diamine Catalysts: An Unusual Achiral Counteranion Induced Reversal of Enantioselectivity

摘要

Benzodiazepines form an important class of heterocycles with pharmacological activities and are considered as "privileged scaffolds in medicinal chemistry. 1,5-Benzodiazepines and their derivatives belong to this family, and have recently attracted much attention. Recent medical research has shown that the sense of chirality of the 1,5-benzodiazepine core of these molecules can play a very important role in determining their bioactivity. However, the asymmetric synthesis of enantiomerically pure 1,5-benzo-diazepine derivatives has been less investigated, and to the best of our knowledge, there is only one report describing the synthesis of 2,4-substituted 2,3,4,5-tetrahydro-lZ7-l,5-benzodiazepines.