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Palladium-Catalyzed Annulation of Internal Alkynes: Direct Access to π-Conjugated Ullazines
Danyang Wan1, Xiaoyu Li1, Ruyong Jiang1
1Key Laboratory of Green Chemistry and Technology of Ministry of Education, College of Chemistry, and State Key Laboratory of Biotherapy, West China Medical School, Sichuan University , 29 Wangjiang Road, Chengdu 610064, P. R. China.
Abstract:
A palladium-catalyzed cyclization reaction of 1-(2,6-dibromophenyl)-1H-pyrroles with alkynes has been developed to construct various π-conjugated indolizino[6,5,4,3-ija]quinolones (ullazines) with a reactive functional group tolerance. As illustrative examples, three new ullazine-based sensitizers are synthesized, and the performance of these dyes is examined in DSSC devices, which demonstrates the potential of direct C-H functionalization in the construction of organic optoelectronic materials.
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