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Asymmetric Synthesis of Spiropyrazolones through Phosphine‐Catalyzed [4+1] Annulation |
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| Authors: | Dr Xiaoyu Han Dr Weijun Yao Dr Tianli Wang Ziyu Yan Jacek Kwiatkowski Prof Dr Yixin Lu |
| Institution: | 1. Zhejiang Provincial Key Laboratory for Chemical & Biochemical Processing Technology of Farm Products, School of Biological and Chemical Engineering, Zhejiang University of Science and Technology, No. 318 Liuhe Road, Hangzhou, 310023 (China);2. Department of Chemistry & Medicinal Chemistry Program, Life Sciences Institute, National University of Singapore (NUS), 3 Science Drive 3, Singapore 117543 (Singapore) |
| Abstract: | An enantioselective synthesis of spiropyrazolones from allenoate‐derived MBH acetates and pyrazolones through a phosphine‐mediated 4+1] annulation process has been developed. Spiropyrazolones were readily prepared in good chemical yields and good to high enantioselectivities. This is the first asymmetric example in which α‐substituted allenoates were utilized as a C4 synthon for phosphine‐catalyzed 4+1] annulation. |
| Keywords: | [4+1] annulation allenoates chiral phosphines spiro compounds spiropyrazolones |