A palladium‐catalyzed highly stereoselective sulfonylation of vinylethylene carbonates for the precise synthesis of structurally diverse (Z)‐allylic sulfones was achieved with excellent regioselectivity and stereoselectivity (Z/E ratio, up to 99 : 1). This protocol used inexpensive sodium sulfinates as sulfonyl sources to construct valuable (Z)‐allylic sulfones in good to excellent yields. The controlling
Pd-Catalyzed Enantio- and Regioselective Formation of Allylic Aryl Ethers
作者:Jianing Xie、Wusheng Guo、Aijie Cai、Eduardo C. Escudero-Adán、Arjan W. Kleij
DOI:10.1021/acs.orglett.7b03247
日期:2017.12.1
A general methodology for the synthesis of enantioenriched tertiary allylic aryl ethers through Pd-catalyzed decarboxylative reactions of vinyl cyclic carbonates and phenols is presented. Switching of the regioselectivity toward the formation of linear products by a judicious choice of the ligand is also reported.
Palladium-Catalyzed Asymmetric Decarboxylative Cycloaddition of Vinylethylene Carbonates with Michael Acceptors: Construction of Vicinal Quaternary Stereocenters
作者:Ajmal Khan、Lei Yang、Jing Xu、Long Yi Jin、Yong Jian Zhang
DOI:10.1002/anie.201407013
日期:2014.10.13
An efficient method for the diastereo‐ and enantioselective construction of vicinal all‐carbon quaternarystereocenters through palladium‐catalyzed decarboxylativecycloaddition of vinylethylenecarbonates with activated Michaelacceptors was developed. By using a palladium complex generated in situ from [Pd2(dab)3]⋅CHCl3 and a phosphoramidite ligand as a catalyst under mild reaction conditions, the
An efficient method for the enantioselective construction of β‐substituted β‐vinylglycinol derivatives through palladium‐catalyzed decarboxylative cycloaddition of vinylethylene carbonates with isocyanates was developed. By using a palladium complex generated in situ from [Pd2(dba)3]⋅CHCl3 (dba=dibenzylideneacetone) and (S)‐Segphos as a catalyst under mild reaction conditions, the process provided
A diastereoselective (3 + 2) cycloaddition of N-sulfonyl ketimines with vinylethylene carbonates (VECs) in the presence of Pd2dba3·CHCl3 and PPh3 has been developed. The reaction of various substituted VECs and diverse cyclic N-sulfonyl ketimines proceeded smoothly under mild conditions, giving highly functionalized oxazolidine frameworks in good to excellent yields with moderate to good diastereoselectivities