Rh(III)-catalyzed oxidative synthesis of pyrazoles from azomethines and acrylamides

A cationic Rh(III) complex has been developed to catalyze the oxidative coupling of azomethine imines to acrylamides, to give trisubstituted pyrazoles in moderate yield. In this process, the olefinic C–H bond of the acrylamide undergoes C–H activation, and the reaction subsequently proceeds via a different selectivity to that reported for the coupling of acrylate esters.

摘要将三价铑离子配合物用于催化甲亚胺内盐与取代的丙烯酰胺之间的氧化偶联反应, 14;实现了三取代的吡唑化合物的合成. 在这个过程中, 14;取代的丙烯酰胺的烯烃发生了C–H键活化. 此类反应和用丙烯酸酯时的反应具有不同的选择性.

Graphical abstractRh(III)-catalyzed oxidative coupling of azomethine imines with acrylamides has been achieved to give trisubstituted pyrazoles. The reaction proceeds via C-H activation of the acrylamide substrate.Figure optionsDownload full-size imageDownload as PowerPoint slide