Benzylidene imidazolones with ortho- secondary aminogroup undergo acid-promoted chemodivergent spirocyclization. Strong Lewis acids provide access to spirocyclic tetrahydroquinolines via [1,5]-hydride shift triggered cyclization despite of the presence of free secondary amino group. Brønsted acids promote unprecedented intramolecular umpolung hydroamination reaction with the formation of spirocyclic indolines
具有邻仲
氨基的亚苄基
咪唑酮经历酸促进的
化学发散螺环化。尽管存在游离的仲
氨基,但强
路易斯酸通过 [1,5]-
氢化物移位触发的环化作用提供了获得螺环
四氢喹啉的途径。布朗斯台德酸促进前所未有的分子内 umpolung 加
氢胺化反应,形成螺环二氢
吲哚。每个过程都以排他的原子经济方式进行。