Nickel-Catalyzed [3 + 3] Annulation of 1,3-Dicarbonyl Compounds with Alkynes for the Synthesis of Functionalized
Xiumei Xu1, Shiru Zhao1, Tongtong Ni1
1Engineering Technology Research Center of Henan Province for Solar Catalysis, College of Chemistry and Pharmaceutical Engineering, Nanyang Normal University, Nanyang 473061, China.
Abstract:
An elegant nickel(II)-catalyzed [3 + 3] annulation strategy has been established for the efficient synthesis of pyranones from readily available 1,3-dicarbonyl compounds and alkynes. Mechanistically, this transformation proceeds via a Ni(II)-mediated C-H activation/alkyne insertion/cyclization cascade under redox-neutral conditions, and the oxygen atom of the pyranone core is unambiguously confirmed to originate from the 1,3-dicarbonyl starting material. This protocol features a broad substrate scope and excellent functional group tolerance, which are crucial advantages for its potential application in organic synthesis.
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