(十)-樟脑缩苄胺体系的不对称羰基加成反应

Asymmetric Carbonyl Addition Reaction of (+)-Camphor Imine Derived from Benzylamine

本文通过(+)-樟脑缩苄胺(1)与不同醛、酮韵不对称加成,经转氨合成了1,2取代-2-氨基乙醇(2)。反应的非对映选择性经NMR测定为16—70％de.;苏式、赤式异构体的含量比由HPLC法测定,其值接近1。由于立体位阻的原因加成反应发生在锂化物3的Re面。

The 1, 2-substituted-2-aminoethanol derivatives (2a—2f) were synthesized from the asymmetric addition of (+)-camphor imine (1) derived from benzylamine to a variety of aldehydes or ketones (4). The diastereoselectivities ranging from 16—70％ were determined by NMR spectra of addition products (5a—5f) and the ratios (about 1) of the threo and erythro isomers with HPLC. For steric reasons, the lithium compound (3) derived from imine (1) requires carbonyl addition to occur from the Reface.