Dehydrogenative [4 + 2] Annulation of 1-Indanones with Alkynes Enabled by In-Situ-Generated Nickel Hydride
Xu Zhang1, Mengfan Chang1, 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:
A practical and effective nickel-catalyzed dehydrogenative [4 + 2] annulation of 1-indanones with alkynes was reported. In this protocol, nickel-catalyzed desaturation of 1-indanones and nickel hydride catalyzed coupling with alkynes were first incorporated. A cyclopentadiene-type nickel hydride species was generated in situ via β-H elimination, and they subsequently reacted with a wide variety of alkynes to afford various benzo[a]fluorenone derivatives in good yields and regioselectivity.
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