Asymmetric synthesis of a-(heteroaryl)alkylamines and a -amino acids via nucleophilic 1,2-addition of lithiated heterocycles to aldehyde SAMP-hydrazones

Authors : Dieter ENDERS, Giuseppe DEL SIGNORE, Gerhard RAABE

Pages : 492-518

Doi:10.3906/kim-1302-71

View : 18 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The asymmetric synthesis of a-insert ignore into journalissuearticles values(heteroaryl);alkylamines was accomplished by employing a diastereoselective nucleophilic 1,2-addition of lithiated aromatic heterocycles to aldehyde SAMP-hydrazones, followed by BH3 . THF or SmI2 promoted removal of the chiral auxiliary. The CBz or benzoyl-protected amines were obtained in good yields insert ignore into journalissuearticles values(40%--78%); and excellent enantiomeric excesses insert ignore into journalissuearticles values(ee = 88%--99%);. The methodology can be applied to the synthesis of highly enantioenriched a-amino acids insert ignore into journalissuearticles values(ee = 90%--99%);.
Keywords : Amines, asymmetric synthesis, SAMP hydrazone, nucleophilic addition, amino acids