Ruthenium(II)-Enabled para-Selective C–H Difluoromethylation of Anilides and their Derivatives
Yingsheng Zhao presents the Ru(II)-enabled C–H difluoromethylation of anilides.
Highly regioselective functionalization of a C–H bond to construct complex synthetic structural units is an important and attractive process in synthetic chemistry. Especially, the highly site-selective introduction of fluorine atom(s) into aromatic rings is of particular value, because it can cause significant changes in the chemical and physical properties of biologically active compounds. However, effective strategies to achieve selective para-C–H functionalization of aniline derivatives are still limited in comparison with ortho-chelation cyclometalation processes, due to the large distance between the C–H bond and the transition-metal center. Recently, the research group of Professor Yingsheng Zhao at Soochow University (P. R. of China) developed a general approach for accomplishing the para-selective C–H difluoromethylation of anilides, indolines, and quinolines by employing a ruthenium catalyst.