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Cobalt-Catalyzed Chemo- and Stereoselective Arylative Carbocyclization of 1,6-Allenynes
Tao Wang1, Ji-Xun Guan1, Yun-Xuan Tan1
1The Research Center of Chiral Drugs, Shanghai Frontiers Science Center of TCM Chemical Biology, Innovation Research Institute of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, People's Republic of China.
Abstract:
Different from the well-investigated enynes, transition-metal-catalyzed carbocyclization reactions of allenynes are more attractive as a result of the unique structure and versatile reactivity of allenes. Herein, we report the first cobalt-catalyzed highly chemo- and stereoselective arylative carbocyclization of 1,6-allenynes with arylboronic acids, affording five-membered carbocycles and heterocycles with moderate to high yields, broad substrate scope, and wide functional group compatibility. Moreover, several mechanistic experiments were conducted to gain insight into the reaction process.
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