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1.
An efficient copper catalyst system, Cu2O/β-ketoimine L1, for the N-arylation of nitrogen-containing heterocycles with aryl iodides and bromides has been developed. The system works well with the electron-rich, -neutral, and -deficient aryl bromides to afford the products in good to excellent yields. 相似文献
2.
New (S)-pyrrolidinylmethylimidazole ligands (4a-c) have been readily synthesized in a straightforward fashion from least expensive starting materials in short steps in high yields. Relatively mild and highly efficient CuI-catalyzed N-arylation procedures for imidazoles with aryl and heteroaryl bromides or chlorides have been developed in the presence of 4a and Cs2CO3. It is important to note that the protocol could tolerate functional groups such as ester, nitrile, nitro, ketone, free hydroxyl, and free primary amine on the aryl halide. The protocol could also be applicable to other pi-electron-rich nitrogen heterocycles (pyrrole, pyrazole, indole, benzimidazole, and triazole), affording the N-arylazoles in good to excellent yields. 相似文献
3.
Huiqing Yin Ming Jin Wei Chen Chen Chen Likang Zheng Ping Wei Shiqing Han 《Tetrahedron letters》2012,53(10):1265-1270
A simple and mild method for the coupling of aryl halides with amino alcohols and diamines is described. The reactions can be performed under ligand-free and solvent-free conditions, and generate the products in good yield. 相似文献
4.
Fui-Fong YongYong-Chua Teo Guan-Leong ChuaGina Shiyun Lim Yizhen Lin 《Tetrahedron letters》2011,52(11):1169-1172
A convenient and efficient protocol has been developed for the cross-coupling of amides and aryl iodides using a ligand-free copper(I) oxide catalyst in water. A variety of amide derivatives afforded the corresponding N-arylated products in moderate to good yields (up to 88%). 相似文献
5.
Yi-Zheng Huang 《Tetrahedron letters》2008,49(6):948-951
Cu2O/ninhydrin was found to be an efficient catalyst system for the N-arylation of nitrogen-containing heterocycles with aryl and heteroaryl iodides, bromides and even unactivated chlorides to give the products in moderate to excellent yields. 相似文献
6.
Tetrazole-1-acetic acid was found to serve as a superior ligand for CuI-catalyzed N-arylation of imidazoles with aryl iodides under a low catalyst loading (5 mol% of CuI). A variety of aryl iodides could be aminated to provide the N-arylated products in good to excellent yields without the need of an inert atmosphere. 相似文献
7.
Relatively mild and highly efficient CuI-catalyzed N-arylation procedures for nitrogen-containing heterocycles (e.g., imidazoles, benzimidazoles, pyrroles, pyrazoles, indoles, triazoles, etc.) with aryl and heteroaryl halides have been developed. The protocols can be performed easily and tolerate a number of functional groups, such as ester, nitrile, nitro, ketone, free hydroxyl, and free primary amine on the aryl halide. 相似文献
8.
Two simple and inexpensive systems for copper-catalyzed N-arylations of sulfoximines with aryl bromides and aryl iodides have been developed. Using 10 mol % of a copper(I) salt in combination with 20 mol % of a 1,2-diamine and Cs2CO3 provides N-arylated sulfoximines in high yields. Various functional groups and heteroatoms are tolerated. The method is complementary to the known protocols for N-arylations of sulfoximines, which require stoichiometric quantities of copper salts or cost-intensive palladium/BINAP catalysts. 相似文献
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10.
《Tetrahedron letters》2014,55(51):7121-7123
An efficient protocol for ligand-free Cu-catalyzed N-arylation of heteroarylamines has been developed. With the use of 1% CuI, a wide range of aryl iodides and bromides coupled with heteroarylamines to afford the corresponding products in high yields. Further, this protocol is particularly suitable for reactions of the most hindered aryl iodides with 2-aminopyridines. 相似文献
11.
A practical copper-catalyzed N-arylation of NH-containing heterocycles with arenediazonium tetrafluoroborates has been developed using CuCl as catalyst and K2CO3 as additive under ligand-free conditions. This reaction system has wide substrate scope including imides, 1H-pyrazole, 1H-tetrazoles, 1,2-benzisothiazol-3(2H)-one, and related sulfonamides and gives moderate to excellent yields (up to 95%) of the desired products. This strategy is very general, simple, environmentally friendly, and tolerant of oxygen. 相似文献
12.
10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-deficient functional groups can be well tolerated under this mild reaction conditions. 相似文献
13.
A practical and promising protocol was developed for N-arylations of various amines with differently substituted aryl halides. The processes are efficiently promoted by the catalyst system involving the environmentally benign Fe2O3 and the universal ligand L-proline. The versatility, convenient operation, low cost, and environmental friendliness, in combination with the high yields, render this method viable for use in both laboratory research and larger industrial scales. 相似文献
14.
Akhilesh Kumar Verma Jaspal Singh V. Kasi Sankar Ritu Chaudhary Ramesh Chandra 《Tetrahedron letters》2007,48(24):4207-4210
Benzotriazole (BtH) is an efficient ligand for the Cu-catalyzed N-arylation of imidazoles with aryl and heteroaryl halides. A combination of CuI/BtH was found to be an efficient and inexpensive catalyst system to carry out the N-arylation of imidazoles affording the corresponding products in good to excellent yields. 相似文献
15.
Xiang Wang Anil Guram Michael Ronk Jacqueline E. Milne Jason S. Tedrow Margaret M. Faul 《Tetrahedron letters》2012,53(1):7-10
This Letter describes a copper catalyzed sulfonamide coupling reaction with aryl bromides to form N-aryl sulfonamides under mild conditions, including the first examples of Cu-catalyzed sulfonamide coupling at room temperature. The reaction protocol tolerates a broad range of substrates including a variety of primary and secondary sulfonamides and challenging heteroaryl bromides such as 2-bromothiazole. 相似文献
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17.
A ligand free, copper-catalyzed N-arylation reaction of amines with diheteroaryl halides in heterogeneous medium at room temperature has been developed. The protocol is very effective for low boiling amines and useful for amines available in aqueous solution. The reaction gives chemospecific arylation of amines with diheteroaryl halides in the mixture monoheteroaryl halides, diheteroaryl halides and carbocyclic aryl halides. The reaction is also chemospecific with respect to arylation of aliphatic amines. Monoarylated piperazines were also synthesized at room temperature following this protocol. 相似文献
18.
Mark Kuil Gerben M. Visser Jan Willem Terpstra Piet W.N.M. van Leeuwen 《Tetrahedron letters》2005,46(14):2405-2409
A highly efficient copper(I)-catalyzed N-arylation of azaheterocycles with various aryl halides is reported. The N-arylation reaction can be carried out using as low as 0.5 mol % of (Cu(I)OTf)2·PhH and 1.0 mol % of 4,7-dichloro-1,10-phenanthroline as the ligand. Furthermore, cheap and stable copper precursors like Cu(I)I and Cu(II)(OAc)2·H2O and the cheap and mild base K2CO3 can be used. 相似文献
19.
With the growing demand of environmentally friendly reagents for organic reactions, for the first time the utility of D-glucose as a ligand in its direct form has been described using a typical example of copper-catalyzed coupling reaction for phenol synthesis with a high degree of selectivity and easy catalyst removal. 相似文献
20.
Intra- and intermolecular palladium-catalyzed cross-coupling of cyclopropanols with aryl halides can be achieved in good yields under mild conditions. 相似文献