Palladium-Catalyzed Cascade Dearomative Spirocyclization and C-H Annulation of Aromatic Halides with Alkynes
Xingrong Liao1, Fulin Zhou1, Zhengyang Bin1
1Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, Sichuan University, 29 Wangjiang Road, Chengdu 610064, P. R. China.
Abstract:
Described herein is a palladium-catalyzed intermolecular dearomative annulation of aryl halides with alkynes, which provides a rapid approach to a class of structurally unique spiroembedded polycyclic aromatic compounds. The cascade process is accomplished by a sequential alkyne migratory insertion, Heck-type dearomatization, and C-H bond annulation. Further optoelectronic study indicated this fused spirocyclic scaffold could be a potential host material for OLEDs, as exemplified by a fabricated red PhOLED device with a maximum external quantum efficiency of 23.0%.
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