1463489-36-2Relevant academic research and scientific papers
Construction of optically active quaternary propargyl amines by highly enantioselective zinc/BINOL-catalyzed alkynylation of ketoimines
Huang, Gaochao,Yin, Zengsheng,Zhang, Xingang
, p. 11992 - 11998 (2013/09/23)
A general and efficient method for the highly enantioselective alkynylation of ketoimines through a zinc/1,1-bi-2-naphthol (BINOL)-catalyzed process has been developed. A variety of ketoimines, including α-fluoroalkyl α-imine esters, α-aryl α-imine esters, and trifluoromethyl aryl ketoimines, are applicable and provide their corresponding quaternary propargyl amines in excellent yields with high ee values (up to 99 % ee). Both the steric and electronic effects of substituents at the 3,3 positions of BINOL are critical for the reaction efficiency and enantioselectivity. To demonstrate the usefulness of the method, (R)-α-CF3 α-proline has been prepared in a highly efficient manner. The notable features of this protocol are its broad substrate scope, high reaction efficiency (up to 99 %) and enantioselectivity (up to 99 % ee), low catalyst loading (5 mol % of BINOL derivative), and mild reaction conditions. Copyright
