Chemodivergent Spirocyclization of 2‐Sec‐Aminobenzilidene Imidazolones: Lewis Versus Brønsted Acids Catalysis
作者:Dmitrii S. Ivanov、Elvira R. Zaitseva、Alexander Yu. Smirnov、Dina A. Rustamova、Andrey A. Mikhaylov、Maria A. Sycheva、Darya A. Gluschenko、Nadezhda S. Baleeva、Mikhail S. Baranov
DOI:10.1002/adsc.202200109
日期:2022.4.26
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。