Experimental and Computational Studies on the Directing Ability of Chalcogenoethers in Palladium‐Catalyzed Atroposelective C−H Olefination and Allylation
Gang Liao, Tao Zhang, Liang Jin, Bing‐Jie Wang, Cheng‐Kai Xu, Yu Lan, Yu Zhao, Bing‐Feng Shi
Abstract
We present herein our experimental and DFT computational studies on the directing ability of chalcogenoether motifs in Pd-catalyzed atroposelective C-H functionalization. The thioether motif was found to be a superior directing group compared to the corresponding ether and selenoether in terms of reactivity and enantiocontrol. Remarkably, DFT calculation provided a predictive model for the optimization of reaction conditions and the interpretation of the origin of enantioselectivity. Both Pd-catalyzed enantioselective C-H olefination and allylation reactions were successfully developed using chiral phosphoric acids as efficient ligands, providing a broad range of axially chiral biaryls in good yields with excellent enantioselectivities. The highly enantio- and diastereoselective construction of polyaryls bearing multiple stereogenic axes, gram-scale reaction and various chemical transformations make this protocol more attractive and significant.