Condensation of Laterally Lithiated o-Methyl and o-Ethyl Benzamides with Imines Mediated by (−)-Sparteine. Enantioselective Synthesis of Tetrahydroisoquinolin-1-ones
摘要:
The first asymmetric synthesis of tetrahydroisoquinolin-1-ones using a (-)-sparteine-mediated lateral metalation-imine addition sequence to furnish 3-phenyl tetrahydroisoquinolinones 3a with enantioselectivities up to 81% ee is described (Scheme 4). For amide 7b, imine addition products 10 and 11 have been obtained with high diastereoselectivities (91-97% de) and enantioselectivities (91-98% ee) (Scheme 8).