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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Asymmetric Synthesis of Fluorinated Cyclobutenes Containing Quaternary Carbon Stereocenters by Rh-Catalyzed
Fushan Yuan1, Jie Jia1, Hui-Ru Jin1
1West China School of Public Health and West China Fourth Hospital, and State Key Laboratory of Biotherapy, Sichuan University, Chengdu, 610041, China.
Abstract:
Fluorinated four-membered rings represent valuable structural motifs in bioactive molecules and pharmaceuticals; however, the asymmetric synthesis of such fluorinated frameworks bearing chiral quaternary carbon centers has not yet been achieved. Herein, we report a Rh-catalyzed enantioselective defluoroarylation of gem-difluorinated cyclobutenes with aryl boronates, enabling the asymmetric construction of fluorinated cyclobutenes bearing chiral quaternary carbon centers with high enantioselectivity via an addition/β-fluoride elimination process. In situ treatment with an additional distinct aryl boronate enables one-pot bis-defluoroarylation to give unsymmetrical diarylated cyclobutenes.
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