Manganese-Catalyzed C−H Amidation of Heteroarenes in Water
作者:Xianqiang Kong、Long Lin、Bo Xu
DOI:10.1002/adsc.201800544
日期:2018.8.6
We have developed an efficient manganese‐catalyzed amidation of various heteroarenes via C−H bond activation using readily available sulfonyl azides. The key step is heteroarene directed electrophilic aromatic metalation using MnBr(CO)5 as catalyst. This method offers excellent chemical yields and regioselectivity with good functional group tolerance. This base metal catalyzed reaction proceeds efficiently
We first report the direct ortho C–Hamidation of arenes with azides by using a novel and inexpensive RuHCl(CO)(PPh3)3 catalyst. The reaction proceeds efficiently in high yield over a broad range of substrates without requirement of any additional silver salt or additive.
A copper-catalyzed C-H amidation process, with azides as amino sources under oxidant-free conditions, has been developed. When N-heterocycles were employed as directing groups, sulfonylazide and benzoylazide could be used as amidating reagents to provide corresponding N-arylamides. When amidines or imine were used, tandem C-N/N-N bond formation occurred to afford indazole derivatives in one pot.