Nickel-Catalyzed Enantio- and Diastereoselective Three-Component Coupling of 1,3-Dienes, Aldehydes, and Silanes Using Chiral N-Heterocyclic Carbenes as Ligands

摘要

Nickel(0)-catalyzed asymmetric three-component coupling of 1,3-dienes, aldehydes, and silanes has been realized utilizing a chiral N-heterocyclic carbene as a ligand. On the basis of the screening of various NHC precursors, an imidazolium salt having 1-(2,4,6-trimethylphenyl)propyl groups on the nitrogen was designed and synthesized. In this reaction, various coupling products were produced in good yields with high regio-, diastereo- (anti selective in the case of the internal 1,3-diene), and enantioselectivities (up to 97% ee).