Access to α-Pyrones via an NHC-Catalyzed Formal [3 + 3] Cycloaddition/Elimination
Minjie Bi1, Feiyang Li1, Mengjie Qi1
1College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China.
None:
α-Pyrones, which serve as core structures in many natural products and important biomolecules, exhibit promising biological activities. Herein, we report an efficient N-heterocyclic carbene (NHC)-catalyzed formal [3 + 3] cycloaddition/elimination reaction that directly converts readily available α-bromocinnamaldehydes and pyridinium salts into diverse α-pyrones under mild conditions. This method exhibits broad functional group tolerance and delivers a wide range of substituted α-pyrone derivatives in high yields.
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