A multicomponent Kröhnke reaction of chalcones with 1-(3,3,3-trifluoro-2-oxopropyl)pyridin-1-ium bromide and ammonium acetate is described. This strategy allows efficiently construction of a series of 2-trifluoromethyl pyridines with broad functional groups.
Stereoselective Synthesis of Atropisomeric Bipyridine <i>N,N′</i>-Dioxides by Oxidative Coupling
作者:Yasuaki Fukazawa、Vladimir Yu. Vaganov、Sergei A. Shipilovskikh、Aleksandr E. Rubtsov、Andrei V. Malkov
DOI:10.1021/acs.orglett.9b01687
日期:2019.6.21
Bipyridine N,N′-dioxide is a structural fragment found in many bioactive compounds. Furthermore, chiral analogues secured their place as powerful Lewis base catalysts. The scope of the existing methods for the synthesis of atropisomeric bipyridine N,N′-dioxides is limited. Herein, we present a practical, highly chemo- and stereoselective method for oxidative dimerization of chiral pyridine N-oxides using