Medium-Ring Nitrogen Heterocycles through Migratory Ring Expansion of Metalated Ureas
作者:Jessica E. Hall、Johnathan V. Matlock、John W. Ward、Katharine V. Gray、Jonathan Clayden
DOI:10.1002/anie.201605714
日期:2016.9.5
benzo‐fused nitrogen heterocycles (indolines, tetrahydroquinolines, and their homologues) undergo migratory ring expansion through deprotonation of their benzylic urea derivatives with lithium diisopropylamide (LDA) in the presence of N,N′‐dimethylpropylideneurea (DMPU). The products of the reactions are benzodiazepines, benzodiazocines, and their homologues, with ring sizes of 8–12. The reactions tolerate a
简单的苯并稠合的氮杂环(二氢吲哚,四氢喹啉及其同系物)在N,N'-二甲基丙稀酰胺(DMPU)的存在下,通过其苄基脲衍生物与二异丙基氨基化锂(LDA)的去质子化而经历迁移环扩展。反应的产物是苯并二氮杂,、苯并二氮杂s及其同系物,环大小为8-12。该反应容许一定范围的取代基图案和类型,并且可以表现出对映特异性或非对映选择性。这些难以获得的中环氮杂环的有效合成迅速产生了相当大的复杂性。