A convenient and practical catalytic method for the preparation of caffeic acid esters is reported. This esterification was carried out with high efficiency in the presence of ytterbium triflate in nitromethane without any other auxiliary reagents. The wide scope of application and especially the higher reactivity and more convenient procedure than previous methods make it a valuable application for the synthesis of caffeic acid esters and other cinnamic acid esters.
报告中介绍了一种方便实用的催化方法来制备咖啡酸酯。这种酯化反应是在硝基甲烷中三酸镱的存在下高效进行的,无需任何其他辅助试剂。与以前的方法相比,该方法应用范围广,特别是反应活性更高,操作过程更简便,因此在合成咖啡酸酯和其他肉桂酸酯方面具有重要的应用价值。