Diversity-Oriented Synthesis of β-Lactams and γ-Lactams by Post-Ugi Nucleophilic Cyclization: Lewis Acids as Regioselective Switch
作者:Zhenghua Li、Upendra Kumar Sharma、Zhen Liu、Nandini Sharma、Jeremy N. Harvey、Erik V. Van der Eycken
DOI:10.1002/ejoc.201500270
日期:2015.6
Heterocyclic fused α-methylene β-lactams were successfully synthesized by a post-Ugi InIII-catalyzed intramolecular addition reaction. Switching from InCl3 to AlCl3 led to the regioselective synthesis of α,β-unsaturated γ-lactams. Moreover, replacing terminal alkynes by substituted alkynes in the Ugi adducts resulted in the exclusive formation of γ-lactams with both catalytic systems.
通过后Ugi InIII催化的分子内加成反应成功合成了杂环稠合α-亚甲基β-内酰胺。从 InCl3 转换为 AlCl3 导致 α,β-不饱和 γ-内酰胺的区域选择性合成。此外,在 Ugi 加合物中用取代的炔烃取代末端炔烃导致两种催化体系均形成 γ-内酰胺。