Palladium-catalyzed asymmetric allenylic alkylation: construction of multiple chiral thiochromanone derivatives
Li-Xia Liu1,2, Yu-Qing Bai1,2, Xiang Li1
1State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences Dalian 116023 China cbyu@dicp.ac.cn ygzhou@dicp.ac.cn.
Abstract:
The development of a new strategy for the construction of chiral cyclic sulfide-containing multiple stereogenic centers is highly desirable. Herein, by the combination of base-promoted retro-sulfa-Michael addition and palladium-catalyzed asymmetric allenylic alkylation, the streamlined synthesis of chiral thiochromanones containing two central chiralities (including a quaternary stereogenic center) and an axial chirality (allene unit) was successfully realized with up to 98% yield, 49.0 : 1 dr and >99% ee.
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