Asymmetric Synthesis of α-Branched Primary Amines on Solid Support via Novel Hydrazine Resins
作者:Dieter Enders、Jan H. Kirchhoff、Johannes Köbberling、Thomas H. Peiffer
DOI:10.1021/ol015721x
日期:2001.4.1
[reaction: see text]. Two novel chiral hydrazine resins for asymmetric solid-phase synthesis have been developed. The enantiopure beta-methoxyamino auxiliaries, derived from trans-4-hydroxy-(S)-proline and (R)-leucine, were attached to Merrifield resin and transformed into their corresponding hydrazines. Immobilization of various aldehydes, followed by 1,2-addition of organolithium reagents to the
Further enantioselective syntheses of α-arylalkanamines via intermediate addition of Grignard reagents to a chiral hydrazone derived from (R)-(−)-2-aminobutan-1-ol
作者:Patricia Bataille、Michel Paterne、Eric Brown
DOI:10.1016/s0957-4166(99)00146-9
日期:1999.4
aldehydes with the chiral hydrazine (R)-(−)-2, derived from 2-aminobutan-1-ol (R)-(−)-1, gave the corresponding hydrazones 5–12. Enantioselectiveaddition of EtMgBr or n-BuMgBr to 5–8 gave the trisubstituted hydrazines 13a–f (d.e.s=100%). Catalytic hydrogenolysis (6 bar/Pd–C/110°C/5 h) of the N–N bond of the latter afforded the enantiomerically enriched α-arylalkanamines (R)-(+)-14a–f (e.e.s=90–93%).