FeCl<sub>3</sub>-Assisted Niobium-Catalyzed Cycloaddition of Nitriles and Alkynes: Synthesis of Alkyl- and Arylpyrimidines Based on Independent Functions of NbCl<sub>5</sub>and FeCl<sub>3</sub>Lewis Acids
作者:Maito Fuji、Yasushi Obora
DOI:10.1021/acs.orglett.7b02708
日期:2017.10.20
NbCl5-catalyzed [2 + 2 + 2] cycloaddition of nitriles with alkynes was used to synthesize pyrimidine derivatives. In this reaction, the use of individual Lewis acids, namely NbCl5 and FeCl3, is a key strategy for achieving the reaction using a catalytic amount of NbCl5. The roles of the two Lewis acids were investigated using FT-IR spectroscopy. The results showed that NbCl5 served as an efficient
NbCl 5催化的炔烃与腈的[2 + 2 + 2]环加成反应用于合成嘧啶衍生物。在该反应中,使用单独的路易斯酸,即NbCl 5和FeCl 3,是使用催化量的NbCl 5实现反应的关键策略。使用FT-IR光谱研究了两种路易斯酸的作用。结果表明,NbCl 5可作为有效的路易斯酸用于腈活化反应,而FeCl 3对路易斯嘧啶显示出更强的路易斯酸度,从而将NbCl 5释放到催化循环中。