Treatment of methyl 2-(benzylideneamino)propanoate with sodium hydride in THF generates an N-sodioazomethine ylide, which shows a very poor stereoselectivity in the cycloaddition with methyl acrylate. However, addition of such a base as triethylamine or t-butyl alcohol improves the selectivity. Chemical properties of the ylide have been discussed on the basis of the selectivity totally different from that of N-lithio analogue.
将甲基2-(苄亚
氨基)
丙酸酯与
钠氢化物在
四氢呋喃中反应,会生成N-
钠偶氮
亚胺亚胺,后者在与
甲基丙烯酸酯的环加成反应中表现出很差的立体选择性。然而,加入
三乙胺或
叔丁醇等碱性添加剂可以提高选择性。关于这种
亚胺的
化学性质已经根据其选择性进行讨论,该选择性与N-
锂类同分异构体截然不同。