Chiral Phosphoric Acid Catalyzed Atroposelective C−H Amination of Arenes. (3rd March 2020)

• Record Type: Journal Article
• Authors: Xia, Wang; An, Qian‐Jin; Xiang, Shao‐Hua; Li, Shaoyu; Wang, Yong‐Bin; Tan, Bin
• Is Part Of: Angewandte Chemie. Volume 132:Number 17(2020)
• Page Start: 6841
• Page End: 6845
• Publication Date: 2020-03-03
• Subjects: Aminierungen -- Atropisomerie -- Chirale Phosphorsäuren -- Heterocyclen -- Organokatalyse; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202000585
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: N‐arylcarbazole structures are important because of their prevalence in natural products and functional OLED materials. C−H amination of arenes has been widely recognized as the most efficient approach to access these structures. Conventional strategies involving transition‐metal catalysts suffer from confined substrate generality and the requirement of exogenous oxidants. Organocatalytic enantioselective C–N chiral axis construction remains elusive. Presented here is the first organocatalytic strategy for the synthesis of novel axially chiral N‐arylcarbazole frameworks by the assembly of azonaphthalenes and carbazoles. This reaction accommodates broad substrate scope and gives atropisomeric N‐arylcarbazoles in good yields with excellent enantiocontrol. This approach not only offers an alternative to metal‐catalyzed C–N cross‐coupling, but also brings about opportunities for the exploitation of structurally diverse N‐aryl atropisomers and OLED materials. Abstract : Gerüstbau : Mit der ersten organokatalytischen Strategie wurden neuartige axial‐chirale N ‐Arylcarbazolgerüste durch Zusammenfügen von Azonaphthalinen und Carbazolen synthetisiert. Das Substratspektrum ist breit, und man erhält atropisomere N ‐Arylcarbazole in guten Ausbeuten bei exzellenter Enantiokontrolle. Dieser Ansatz bietet Möglichkeiten zur Erschließung von strukturell unterschiedlichen N ‐Aryl‐Atropisomeren und OLED‐Materialien. CPA=chirale Phosphorsäure.