Reversal of Regioselectivity in Nucleophilic Difluoroalkylation of α,β-Enones Employing In Situ-Formed Sterically Encumbered Silylium Catalyst
Jinshan Li, Saimei Liu, Rong Zhong, Yaqi Yang, Yuru He, Jianguo Yang, Yongmin Ma, Zhiming Wang
Abstract
An efficient approach for the reversal of regioselectivity in the nucleophilic introduction of difluorinated carbanion into α,β-enones has been developed via a silylium catalysis. The strong electron-withdrawing properties and bulky substituents of in situ-generated silyl triflic imide catalyst is the key for the 1,4-addition reaction to proceed smoothly. The synthetic utility is highlighted by the further use of this method for the synthesis of 2,4,6-triarylsubstituted 3-fluoropyridines in a one-pot manner.
Topics & Concepts
RegioselectivityChemistryCarbanionNucleophileSteric effectsCatalysisIn situNucleophilic additionSilylationCombinatorial chemistryOrganic chemistryFluorine in Organic ChemistryInorganic Fluorides and Related CompoundsAsymmetric Synthesis and Catalysis