Chiral C 2 -symmetric 2,3-disubstituted aziridine and 2,6-disubstituted piperidine as chiral ligands in the addition reaction of diethylzinc with arylaldehydes
作者:Min Shi、Jian-Kang Jiang、Yan-Shu Feng
DOI:10.1016/s0957-4166(00)00479-1
日期:2000.12
Chiral C2-symmetric 2,3-disubstituted aziridines and 2,6-disubstituted piperidines having a β-amino alcohol moiety have been successfully synthesized and their catalytic chiral induction properties have been examined in the asymmetric addition reactions of diethylzinc with arylaldehydes in hexane. When N-(2,2-diphenyl-2-hydroxyethyl)-(S,S)-2,3-bis(methoxymethyl)aziridine 11 was used as a catalytic
已经成功地合成了具有β-氨基醇部分的手性C 2对称的2,3-二取代的氮丙啶和2,6-二取代的哌啶,并已在二乙基锌与芳醛在己烷中的不对称加成反应中研究了它们的催化手性诱导性能。当使用N-(2,2-二苯基-2-羟乙基)-(S,S)-2,3-双(甲氧基甲基)氮丙啶11作为催化手性配体时,形成具有(S)-构型的仲醇高产率为86–92%,而对映体过量(ee's)为11–13%。但是,当N-(2,2-二苯基-2-羟乙基)-(R时,R)-2,6-二取代哌啶衍生物16和20在相同反应条件下用作手性配体,相应仲醇的ee分别为20–30和5%–6%,以及配置。提出了这种反演的合理机制。