The reaction of aromatic and aliphatic imines derived from (S)-valine methyl ester and (S)-valinol with allyl bromide and zinc in tetrahydrofuran affords homoallylic amines with up to 100% diastereoisomeric excess (d.e.), but in the case of the aromatic imines the diastereoselectivity is lowered by increasing the reaction time, owing to the reversibility of the allylation reaction.
由(S)-缬
氨酸甲酯和(S)-缬
氨醇衍生的芳香族和脂肪族
亚胺与椰基
溴和
锌在
四氢呋喃中反应,生成具有高达100%差异异构体过量(d.e.)的同
烯丙胺,但在芳香族
亚胺的情况下,随着反应时间的增加,差异选择性降低,这是由于烯丙基化反应的可逆性所致。