Photo by nickkarvounis from unsplash
Abstract We have developed a transition-metal-free, practical route to benzimidazole-fused 1,4-benzoxazepines. Operationally, the protocol involves a K2CO3-mediated intermolecular ring opening of terminal epoxides by 2-(2-fluorophenyl)benzimidazole, followed by an intramolecular nucleophilic… Click to show full abstract
Abstract We have developed a transition-metal-free, practical route to benzimidazole-fused 1,4-benzoxazepines. Operationally, the protocol involves a K2CO3-mediated intermolecular ring opening of terminal epoxides by 2-(2-fluorophenyl)benzimidazole, followed by an intramolecular nucleophilic aromatic substitution (SNAr) reaction of the resulting products in the presence of NaH. We have also achieved an 11-step synthesis of a chroman-linked benzimidazole-fused 1,4-benzoxazepine using a phenoxide-ion induced 6-exo intramolecular epoxide ring-opening and an alkoxide-ion induced intramolecular SNAr reaction as key steps.
Journal Title: Tetrahedron Letters
Year Published: 2020
Link to full text (if available)
Share on Social Media: Sign Up to like & get
recommendations!