Regiodivergent and Enantioselective Allylic C-H Alkylation of Allyl Ethers: Optimization, Scope, Mechanism and
Hongkai Wang1, Lijuan Song2, Jing Huang1,3
1Institute of Chemical Biology, Shenzhen Bay Laboratory, Shenzhen, 518132, China.
Abstract:
Vinyl ethers and allyl ethers are important motifs in natural products and pharmaceuticals. Among various methods toward their synthesis, direct allylic C-H functionalization of allyl ethers is one of the most efficient approaches. In this study, one of two regioisomers, a vinyl ether or an allyl ether, could be obtained, depending on whether a Lewis acid co-catalyst was present. Furthermore, branched allyl ethers were smoothly prepared in excellent regio- and enantioselectivity (up to 20 : 1 b/l, 99 % ee) by synergistic catalysis with an achiral Pd(0) complex and a chiral Lewis acid catalyst.
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