330682-30-9Relevant articles and documents
Streamlined Synthesis of Diaminopyridines by Pd-Catalyzed Ammonia Coupling with Deactivated Amino-Chloropyridines
Bourriquen, Florian,Bruneau-Voisine, Antoine,Jeandin, Aliénor,Stihle, Etienne,Fantasia, Serena
supporting information, p. 9006 - 9011 (2019/06/24)
An efficient and cost-effective two-step synthesis of diaminopyridines, fundamental building blocks of biologically active compounds, is reported. The advantages over previously reported routes include cost and wider availability of the bromo-chloropyridine starting materials and the straightforward accessibility to an extended array of diaminopyridine regioisomers. The key enabler of this synthetic strategy is the development of an unprecedented palladium-catalyzed coupling reaction of ammonia with chloropyridines deactivated by the presence of an alkylamino substituent. The coupling reaction was accomplished with very low catalyst loadings under remarkably mild reaction conditions, making the system particularly suitable for both academic and industrial applications. The utility of this methodology is exemplified by the application to the synthesis of highly relevant scaffolds, including the synthetic intermediates of the marketed drugs Ribociclib and Palbociclib.
Negishi cross-coupling reactions catalyzed by an aminophosphine-based nickel system: A reliable and general applicable reaction protocol for the high-yielding synthesis of biaryls
Gerber, Roman,Frech, Christian M.
experimental part, p. 11893 - 11904 (2011/11/29)
Treatment of NMP solutions of NiCl2 with 1,1′,1″- (phosphanetriyl)tripiperidine (≈2.05 equiv), dissolved in THF, in air at 25°C forms a highly active catalytic system for the cross-coupling of a large variety of electronically activated, non-activated, deactivated, and ortho-substituted, heterocyclic, and functionalized aryl bromides and aryl chlorides with diarylzinc reagents. Very high levels of conversion and yields were obtained within 2 h at 60°C in the presence of only 0.1 mol% of catalyst (based on nickel) and thus at catalyst loadings far lower than typically reported for nickel-catalyzed versions of the Negishi reaction. Various aryl halides-which may contain trifluoromethyl groups, fluorides, or other functional groups such as acetals, ketones, ethers, esters, lactones, amides, imines, anilines, alkenes, pyridines, quinolines, and pyrimidines-were successfully converted into the corresponding biaryls. Electronic and steric variations are tolerated in both reaction partners. Experimental observations indicate that a molecular (NiI/NiIII) mechanism is operative.
Transition metal-free amination of aryl halides-A simple and reliable method for the efficient and high-yielding synthesis of N-arylated amines
Bolliger, Jeanne L.,Frech, Christian M.
experimental part, p. 1180 - 1187 (2009/04/10)
A simple and reliable reaction protocol for the clean, fast, and high-yielding synthesis of various N-arylated amines derived from reactions of aryl halides with various (also sterically hindered) amines under transition metal-free reaction conditions is presented. Dioxane and KN(Si(CH3)3)2 were found to be the ideal solvent and base for this transformation. The conversion rates and yields observed are excellent and in the majority of the reactions performed significantly higher than that obtained in their catalyzed versions. Furthermore, the selective synthesis of 6-halopyridin-2-amines and asymmetric pyridine-2,6-diamines (derived from consecutive reactions of 2,6-dibromopyridine and 2,6-dichloropyridine, respectively, with different amines) is possible in almost quantitative yields (relative to 2,6-dihalopyridine) within very short reaction times. Purification of the 6-halopyridin-2-amine intermediates is not necessary, allowing the synthesis of pyridine-2,6-diamines in 'one-pot'. However, catalysts are in many cases not required to efficiently and selectively couple aryl halides with amines, making transition metal-free versions of the Buchwald-Hartwig reaction extremely attractive for the synthesis of N-arylated amines with substrates containing substituents on the aryl halide, which either promote regioselectivity and/or do not require regioselective aminations.
Nickel-catalysed synthesis of 3-chloroanilines and chloro aminopyridines via cross-coupling reactions of aryl and heteroaryl dichlorides with amines
Desmarets, Christophe,Schneider, Rapha?l,Fort, Yves
, p. 247 - 250 (2007/10/03)
Selective monoamination of aryl and heteroaryl dichlorides has been carried out using a catalyst combination of Ni(0) associated to 2,2′-bipyridine. The synthesis of novel 3-chloroanilines and chloro aminopyridines in good to excellent yields is allowed u
Nickel-mediated amination chemistry. Part 1: Efficient aminations of (het)aryl 1,3-di and 1,3,5-trichlorides
Desmarets, Christophe,Schneider, Rapha?l,Fort, Yves
, p. 2875 - 2879 (2007/10/03)
The first Ni-catalysed synthesis of di- and triamino substituted benzenes and diamino substituted pyridines from the corresponding aryl chlorides and amines is described. (C) 2000 Elsevier Science Ltd.
