Chelation-assisted iridium-catalyzed hydroalkenylation and hydroarylation/cyclization with conjugated trienes
Yilei Liao1, Cheng Zhang1, Yini Wang1
1College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou, 311121 Zhejiang, China. dingly1987@163.com.
Abstract:
Iridium-catalyzed hydroalkenylation of conjugated trienes by chelation-assisted alkenyl C-H activation of acrylamides has been demonstrated to produce 1,4,6-trienes atom efficiently with excellent regio- and E/Z selectivities. In contrast, the reaction of benzamides and 1,3,5-trienes proceeds by a tandem hydroarylation of the trienes and cyclization via intramolecular 1,2-addition, providing valuable trans-tetrahydroisoquinolinone derivatives. A broad range of aromatic and aliphatic 1,3,5-trienes bearing various functionalities were compatible to deliver target products with high yields and E/Z selectivity. The successful gram-scale preparation and selective hydrogenation to give the alkylation product further demonstrates the practicability of this protocol to potential applications.
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