7022-20-0Relevant articles and documents
Para-Selective C-H Borylation of Common Arene Building Blocks Enabled by Ion-Pairing with a Bulky Countercation
Mihai, Madalina T.,Williams, Benjamin D.,Phipps, Robert J.
supporting information, p. 15477 - 15482 (2019/10/11)
The selective functionalization of C-H bonds at the arene para position is highly challenging using transition metal catalysis. Iridium-catalyzed borylation has emerged as a leading technique for arene functionalization, but there are only a handful of strategies for para-selective borylation, which operate on specific substrate classes and use bespoke ligands or catalysts. We describe a remarkably general protocol which results in para-selectivity on some of the most common arene building blocks (anilines, benzylamines, phenols, benzyl alcohols) and uses standard borylation ligands. Our strategy hinges upon the facile conversion of the substrates into sulfate or sulfamate salts, wherein the anionic arene component is paired with a tetrabutylammonium cation. We hypothesize that the bulk of this cation disfavors meta-C-H borylation, thereby promoting the challenging para-selective reaction.
Synthesis of Phenanthridines through Palladium-Catalyzed Cascade Reaction of 2-Halo-N-Ms-arylamines with Benzyl Halides/Sulfonates
Yang, Si-Yi,Han, Wen-Yong,Zhang, Ding-Lei,Zhou, Xiao-Jian,Bai, Mei,Cui, Bao-Dong,Wan, Nan-Wei,Yuan, Wei-Cheng,Chen, Yong-Zheng
, p. 996 - 1003 (2017/02/15)
An efficient palladium-catalyzed nucleophilic substitution/C–H activation/aromatization cascade reaction between readily available 2-halo-N-Ms-arylamines (Ms = methanesulfonyl) and benzyl halides/sulfonates has been described. A wide variety of phenanthridines were synthesized in a one-pot fashion in moderate to high yields (37–86 %). Notably, this method provides a straightforward, facile approach for the synthesis of phenanthridines. The practicality was further substantiated by successfully carrying out a gram-scale preparation.
Low catalyst loadings for ligand-free copper(I)-oxide-catalyzed N-arylation of methanesulfonamide in water
Tan, Bryan Yong-Hao,Teo, Yong-Chua,Seow, Ai-Hua
, p. 1541 - 1546 (2014/03/21)
A simple and practical protocol for the cross-coupling of methanesulfonamide and aryl iodides under ligand-free copper(I)-oxide-catalyzed conditions in water is reported. The method allows the preparation of a wide variety of synthetically useful N-arylated methanesulfonamides in good to excellent yields (up to 90 %) under the optimized conditions. A convenient and efficient ligand-free method using a copper(I) oxide catalyst at 130 °C in water was developed for the N-arylation of methanesulfonamide with aryl iodides. A variety of functionalized aliphatic and cyclic sulfonamides were coupled with different substituted aryl halides to give the corresponding N-arylated products in good to excellent yields under the optimized conditions. Copyright
