Nickel-Catalyzed Alkenylation of N-Heteroarenes with Fluorinated Alcohols: Direct Access to CF3-Embedded Olefins
Shuvojit Haldar1, Atanu Bera1, Adrija Ghosh1
1Laboratory of Catalysis and Organic Synthesis, Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India.
Abstract:
Herein, a sequential Ni-catalyzed acceptorless dehydrogenation followed by condensation of bench-stable fluorinated alcohols with 2-oxindoles or methyl N-heteroarenes to CF3-embedded olefins is reported. The protocol is tolerant to a series of 2-oxindoles, methyl azaarenes, and primary and secondary fluorinated alcohols, and the late-stage functionalization of a vitamin derivative is a key highlight (>21 examples and up to 89% yield). Preliminary mechanistic studies and control experiments were performed to understand the reaction pathways.
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