5436-83-9Relevant articles and documents
Buchwald-Hartwig amination of aryl esters and chlorides catalyzed by the dianisole-decorated Pd-NHC complex
Zheng, Di-Zhong,Xiong, Hong-Gang,Song, A-Xiang,Yao, Hua-Gang,Xu, Chang
supporting information, p. 2096 - 2101 (2022/04/01)
A modular and generic method for the Buchwald-Hartwig amination reactions of relatively unreactive aryl esters as acyl electrophiles and aryl chlorides as aryl electrophiles has been developed, leading to the efficient synthesis of amides/amines under air conditions and with low catalyst loadings. The success of this catalytic protocol is mainly attributed to the modification of the Pd-IPr skeleton with sterically hindered and electron-donating anisole groups. This method also features good functional group tolerance and excellent chemoselectivities. In summary, the results presented herein suggest the possibility of developing a versatile and general protocol for diverse electrophiles to undergo the Buchwald-Hartwig amination reactions, avoiding too much consideration of the reaction conditions for the substrate-dependent C-N bond formations.
Amide Bond Formation via the Rearrangement of Nitrile Imines Derived from N-2-Nitrophenyl Hydrazonyl Bromides
Boyle, Mhairi,Livingstone, Keith,Henry, Martyn C.,Elwood, Jessica M. L.,Lopez-Fernandez, J. Daniel,Jamieson, Craig
supporting information, p. 334 - 338 (2022/01/20)
We report how the rearrangement of highly reactive nitrile imines derived from N-2-nitrophenyl hydrazonyl bromides can be harnessed for the facile construction of amide bonds. This amidation reaction was found to be widely applicable to the synthesis of primary, secondary, and tertiary amides and was used as the key step in the synthesis of the lipid-lowering agent bezafibrate. The orthogonality and functional group tolerance of this approach was exemplified by the N-acylation of unprotected amino acids.
Dehydrogenative amide synthesis from alcohols and amines utilizing N-heterocyclic carbene-based ruthenium complexes as efficient catalysts: The influence of catalyst loadings, ancillary and added ligands
Wang, Wan-Qiang,Wang, Zhi-Qin,Sang, Wei,Zhang, Rui,Cheng, Hua,Chen, Cheng,Peng, Da-Yong
, (2021/01/05)
The metal-catalyzed dehydrogenative coupling of alcohols and amines to access amides has been recognized as an atom-economic and environmental-friendly process. Apart from the formation of the amide products, three other kinds of compounds (esters, imines and amines) may also be produced. Therefore, it is of vital importance to investigate product distribution in this transformation. Herein, N-heterocyclic carbene-based Ru (NHC/Ru) complexes [Ru-1]-[Ru-5] with different ancillary ligands were prepared and characterized. Based on these complexes, we selected condition A (without an added NHC precursor) and condition B (with an added NHC precursor) to comprehensively explore the selectivity and yield of the desired amides. After careful evaluation of various parameters, the Ru loadings, added NHC precursors and the electronic/steric properties of ancillary NHC ligands were found to have considerable influence on this catalytic process.