Carbene-catalyzed enantioselective addition of benzylic carbon to unsaturated acyl azolium for rapid synthesis of pyrrolo[3,2- c]quinolines

• Main Authors: Wang, Jilan, Li, Yongjia, Sun, Jun, Wang, Hong, Jin, Zhichao, Chi, Robin Yonggui
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2020
• Subjects: Science::Chemistry::Organic chemistry; Carbene Organocatalysis; Asymmetric Synthesis
• Online Access: https://hdl.handle.net/10356/138266
• Institution: Nanyang Technological University

A carbene-catalyzed enantioselective addition of benzylic carbon to α,β-unsaturated acyl azolium intermediate generated via N-heterocyclic carbene catalysis is disclosed. This addition is followed by a stereoselective Mannich reaction and a chemo-selective lactam formation cascade to afford pyrrolo[3,2-c]quinolones as the products with excellent yields and optical purities. This work constitutes an effective asymmetric benzyl sp3-carbon functionalization and single-step rapid access to multicyclic heterocycles bearing four contiguous chiral centers.