Indane-Fused Spiropentadiene Chromanones: A Pd-Catalyzed Spiroannulation Followed by Cyclization via C-H Activation
Abhilash Sharma1,2, Hemanta Hazarika1,2, Manashi Sarmah1
1Applied Organic Chemistry Group, Chemical Science and Technology Division, CSIR-North East Institute of Science and Technology, Jorhat 785006, India.
Abstract:
Pd-catalyzed spiroannulation of 4-bromocoumarin with alkynes has been illustrated. The reaction highlights an interesting process for cascade formation of two five-membered rings through spiroannulation followed by cyclization via C-H activation. This method offers an attractive platform for the synthesis of a broad range of indane-fused spiropentadiene chromanones in good yields.
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