Studies On The Asymmetric Hydrogenation Of Heteroaromatic Compounds, Quinolines And Isoquinolines

In this dissertation, two different strategies have been introduced for the asymmetric hydrogenation of heteroaromatic compounds, quinolines and isoquinolines.1. Developing a highly active catalyst system for the asymmetric hydrogenation of quinolinesThrough optimization of the hydrogenation conditions such as solvent, temperature, hydrogen pressure, chiral ligand, metal precursor, additive, and substrate concentration, 2-substituted quinoline derivatives can be hydrogenated using [Ir(COD)Cl]2/MeO-Biphep/I2 catalyst system with up to 96% ee.Iridium-catalyzed asymmetric hydrogenation of quinolines provides a convenient route to synthesize optically active tetrahydroquinoline derivatives since quinolines are very cheap starting materials. This methodology can be successfully applied to asymmetric synthesis of tetrahydroquinoline alkaloids.In the course of the study, [Ir(COD)Cl]2/(±)-MeO-Biphep/I2 was found to catalyze the dehydrogenation aromatization reactions of 2-substituted 1,2-dihydroquinolines.2. Asymmetric hydrogenation of quinolines and isoquinolines activated by chloroformatesThe above catalyst system [Ir(COD)Cl]2/MeO-Biphep/I2 is effective for...