A PROCESS FOR SYNTHESIS OF CHIRAL 3-SUBSTITUTED TETRAHYDROQUINOLINE DERIVATIVES

摘要

The present invention relates to novel and concise process for the construction of chiral 3-substituted tetrahydroquinoline derivatives based on proline catalyzed asymmetric alpha-functionalization of aldehyde, followed by in situ reductive cyclization of nitro group under catalytic hydrogenation condition with high optical purities. Further the invention relates to conversion of derived chiral 3-substituted tetrahydroquinoline derivatives into therapeutic agents namely (-)-sumanirole (96% ee) and 1-[(S)-3-(dimethylamino)-3,4-dihydro-6,7-dimethoxy-quinolin-1(2H)-yl]propanone[(S)-903] (92% ee).