Rhodium(III)-Catalyzed Directed C−H Amidation of <i>N</i>
-Nitrosoanilines and Subsequent Formation of 1,2-Disubstituted Benzimidazoles
作者:Yanyu Chen、Rong Zhang、Qiujun Peng、Lanting Xu、XianHua Pan
DOI:10.1002/asia.201701287
日期:2017.11.2
An efficient rhodium‐catalyzeddirectC−Hamidation of N‐nitrosoanilines with 1,4,2‐dioxazol‐5‐ones as amidating agents has been developed. This method featured mild reaction conditions, a wide substrate scope and satisfactory yields. Besides, the amidated products could be readily converted to pharmaceutically valuable 1,2‐disubstituted benzimidazoles via an HCl‐mediated deprotection/cyclization process
Palladium-catalyzed decarboxylative ortho-acylation of N-nitrosoanilines with α-oxocarboxylic acids
作者:Jia-Ping Yao、Guan-Wu Wang
DOI:10.1016/j.tetlet.2016.03.009
日期:2016.4
A palladium-catalyzed efficient C–H acylation reaction of N-nitrosoanilines with α-oxocarboxylic acids has been developed. The reaction proceeded smoothly with potassiumpersulfate as the oxidant to afford acylated N-nitrosoanilines in moderate to good yields with a broad substrate scope and good regioselectivity.
An efficient and mild protocol for regioselective synthesis of N-Nitroso aryl ketones by palladium-catalyzed directacylation of arenes using N-Nitroso as directing groups is described. This reaction proceeded smoothly and could tolerate a variety of functional groups. Moreover, this chemistry offers a convenient access to a range of indazoles.
Rhodium-catalyzed tandem acylmethylation/annulation of <i>N</i>-nitrosoanilines with sulfoxonium ylides for the synthesis of substituted indazole <i>N</i>-oxides
作者:Xin-Feng Cui、Guo-Sheng Huang
DOI:10.1039/d0ob00723d
日期:——
ylides through the rhodium(III)-catalyzed C–H activation and cyclization reaction is described here. This protocol employs nitroso as a traceless directing group. The transformation features powerful reactivity, tolerates various functional groups, and proceeds with moderate to good yields under an ambient atmosphere, providing a straightforward approach to access structurally diverse and valuable indazole
C–H Activation-Based Traceless Synthesis via Electrophilic Removal of a Directing Group. Rhodium(III)-Catalyzed Entry into Indoles from <i>N</i>-Nitroso and α-Diazo-β-keto Compounds
A distinct C–H activation-based traceless synthetic protocol viaelectrophilic removal of a directing group is reported, complementing the currently exclusively used nucleophilic strategy. Rh(III)-catalyzed, N-nitroso-directed C–H activation allows the development of a traceless, atom- and step-economic, cascade approach for the synthesis of indole skeletons, starting from readily available N-nitroso