Ni/Chiral Sodium Carboxylate Dual Catalyzed Asymmetric O-Propargylation
Xianghong Xu1, Lingzi Peng1, Xihao Chang1
1Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Abstract:
A highly enantioselective O-propargylation catalyzed by combining a phosphine-nickel complex and an axially chiral sodium dicarboxylate has been developed. The transformation features mild reaction conditions, a broad substrate scope, and excellent functional group tolerance, offering an efficient approach to an array of enantioenriched O-propargyl hydroxylamines. Mechanistic studies support the presumed role of the chiral carboxylate as a counterion for nickel catalysis enabling the discovery of highly stereoselective transformations. The power of this reaction is illustrated by its application in the asymmetric total synthesis of potent firefly luciferase inhibitors and (S)-dihydroyashabushiketol.
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