Sustainable ppm level palladium-catalyzed aminations in nanoreactors under mild, aqueous conditions
作者:Yitao Zhang、Balaram S. Takale、Fabrice Gallou、John Reilly、Bruce H. Lipshutz
DOI:10.1039/c9sc03710a
日期:——
Greening-up aminations: a well-defined palladium pre-catalyst enables ppm-level Pd-catalyzed C–N cross couplings in water under very mild conditions. Comparisons using this protocol vs. traditional amination conditions for preparing key medicinal intermediates are demonstrated.
Dialkylterphenyl Phosphine‐Based Palladium Precatalysts for Efficient Aryl Amination of
<i>N</i>
‐Nucleophiles
作者:Raquel J. Rama、Celia Maya、M. Carmen Nicasio
DOI:10.1002/chem.201903279
日期:2020.1.22
in arylamination reactions. Cationic complexes bearing the phosphines PiPr2 ArXyl2 and PCyp2 ArXyl2 were the most active of the series. These precatalysts have demonstrated a high versatility and efficiency in the coupling of a variety of nitrogen nucleophiles, including secondary amines, alkyl amines, anilines, and indoles, with electronically deactivated and ortho-substituted arylchlorides at low
amines and nucleobases have also been used, affording the corresponding coupling products in good to excellent yields. Moreover, this method has been employed for chemoselective C–N arylation of aminophenols and further utilized for the synthesis of carbazole natural products, avoiding the protection and deprotection steps.
environmentally friendly and economically favorable approach to the formation of C–N bonds is presented. The methodology is particularly interesting in that the reaction is realized under both solvent- and ligand-free conditions and involves the use of a low loading of a palladium catalyst dispersed with the reactants on a suitable solid support. The reaction proceeds rapidly under microwave irradiation. An environmentally
Combined experimental/theoretical study of <scp>d</scp>-glucosamine promoted Ullmann-type C–N coupling catalyzed by copper(<scp>i</scp>): does amino really count?
作者:Xin Ge、Xinzhi Chen、Chao Qian、Shaodong Zhou
DOI:10.1039/c6ra03015g
日期:——
type C–N coupling reaction catalyzed by copper(I) with D-glucosamine derivatives as promoters was studied by means of combinedexperimental/theoretical investigation. The catalytic role of D-glucosamine was addressed. In contrast with previous speculations, the amino group may not count in the catalytic cycle in which the oxidative addition/reductive elimination mechanism works. Experimental results