Carbene-catalyzed atroposelective annulation and desymmetrization of urazoles

An NHC-catalyzed atroposelective reaction between ynals and urazoles is disclosed. The reaction establishes a chiral C-N axis via an atroposelective [3 + 2] annulation/desymmetrization process. Our reaction allows efficient access to axially chiral and heteroatom-rich urazole derivatives with potential applications in bioactive molecules and catalysis.Agency for Science, Technology and Research (A*STAR)Economic Development Board (EDB)Ministry of Education (MOE)Nanyang Technological UniversityNational Research Foundation (NRF)We acknowledge financial support from the National Natural Science Foundation of China (21772029, 21801051, 21961006, 22001173), The 10 Talent Plan (Shicengci) of Guizhou Province ([2016]5649), the Guizhou Province Returned Oversea Student Science and Technology Activity Program [(2014)-2], the Science and Technology Department of Guizhou Province ([2018]2802, [2019]1020, Qiankehejichu-ZK[2021]Key033), the Program of Introducing Talents of Discipline to Universities of China (111 Program, D20023) at Guizhou University, Frontiers Science Center for Asymmetric Synthesis and Medicinal Molecules, Department of Education, Guizhou Province [Qianjiaohe KY (2020)004], the Basic and Applied Research Foundation of Guangdong Province (2019A1515110906), the Guizhou Province FirstClass Disciplines Project [(Yiliu Xueke Jianshe Xiangmu)- GNYL(2017)008], Guizhou University of Traditional Chinese Medicine, and Guizhou University (China). Singapore National Research Foundation under its NRF Investigatorship (NRF-NRFI2016-06), the Ministry of Education, Singapore, under its MOE AcRF Tier 1 Award (RG108/16, RG5/19, RG1/18), MOE AcRF Tier 3 Award (MOE2018-T3-1-003), the Agency for Science, Technology and Research (A*STAR) under its A*STAR AME IRG Award (A1783c0008, A1783c0010), GSK-EDB Trust Fund, and Nanyang Research Award Grant, Nanyang Technological University