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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Bi(OTf)3-catalyzed addition of isocyanides to 2H-chromene acetals: an efficient pathway for accessing
Longyun Lyu1, Ming Yu Jin, Qijie He
1Department of Chemistry, South University of Science and Technology of China, Shenzhen, Guangdong 518055, China. wang.j@sustc.edu.cn.
Abstract:
Bismuth triflate (Bi(OTf)3) is identified as an efficient catalyst for the direct addition of isocyanides to 2H-chromene acetals. The large scope of isocyanides and chromene acetals makes them suitable substrates in this catalytic system. By this synthetic strategy, a polyfunctional molecular scaffold, 2-carboxamide-2H-chromenes could be prepared efficiently in one step up to 95% yield. In addition, this efficient and practical protocol proceeded smoothly in the gram scale even when the catalytic loading was reduced to 2 mol%.
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