scholarly journals Effect of imidazolinium salts bearing hydroxy substituents on palladium-catalysed Suzuki–Miyaura and Heck coupling reactions

2016 ◽  
Vol 4 (1) ◽  
pp. 76-84
Author(s):  
Adam Morel ◽  
Anna Trzeciak

Palladium anionic complexes with imidazolinium cations containing hydroxyl substituents were used as catalyst precursors in the Suzuki–Miyaura and the Heck cross-coupling. High activity of anionic complexes was noted in the Suzuki–Miyaura reaction of 2-bromotoluene with phenylboronic acid at 40 oC in 2-propanol and a 2-propanol/water mixture using conventional heating or microwaves. Similarly, bromonaphtalene and iodonaphtalene reacted efficiently with naphtylboronic acid and 4-methylnaphtylboronic acid. A remarkably lower activity was noted when anionic palladium complexes were employed in the Heck coupling of 2,3-dihydrofuran with iodobenzene. An increase in conversion in the Heck reaction was achieved when Pd(OAc)2 was used as a catalyst precursor together with imidazolinium salts as co-catalysts.

ChemInform ◽  
2005 ◽  
Vol 36 (27) ◽  
Author(s):  
Rhett C. Smith ◽  
Christina R. Bodner ◽  
Meredith J. Earl ◽  
Nathaniel C. Sears ◽  
Nicholas E. Hill ◽  
...  

2010 ◽  
Vol 63 (2) ◽  
pp. 315 ◽  
Author(s):  
Kai Xu ◽  
Xin-Qi Hao ◽  
Jun-Fang Gong ◽  
Mao-Ping Song ◽  
Yang-Jie Wu

Two new palladium complexes with pyrazole derived ligands 2a–2b have been easily prepared and well characterized by elemental analysis, 1H NMR, 13C NMR, and IR spectra. Their detailed structures are determined by a single-crystal X-ray analysis of 2a. The two compounds were successfully applied to the Suzuki coupling reactions of aryl bromides with phenylboronic acid, in aqueous solution at room temperature under air, giving the desired coupled products in good to excellent yields with catalyst loadings as low as 0.01–0.05 mol-%.


2010 ◽  
Vol 88 (2) ◽  
pp. 99-103 ◽  
Author(s):  
Earl Cook ◽  
Jason D. Masuda ◽  
Aibing Xia

Palladium complexes containing 8-quinolylphosphinite ligands have been synthesized and characterized. Their solid state structures were determined by single-crystal X-ray diffraction. They were found to be active catalysts for Suzuki coupling reactions of phenylboronic acid and various aryl halides.


2017 ◽  
Vol 95 (10) ◽  
pp. 1041-1044 ◽  
Author(s):  
Christina Jones ◽  
Matthew Timm ◽  
Jason D. Masuda ◽  
Aibing Xia

Two palladium complexes containing bis(aminophosphine) ligands have been prepared and characterized. Their solid structures were determined by X-ray single crystal diffraction studies. They were successfully employed in the Suzuki coupling reactions of phenylboronic acid and various aryl chlorides.


2013 ◽  
Vol 16 (1) ◽  
pp. 79
Author(s):  
A.T. Khabiyev ◽  
B.S. Selenova

<p>This study examined investigation of catalytic activity of aryl-ferrocenyl-phosphine (2-methoxyphenyl diferrocenyl phosphine (cat. 1), 2-tert-butyloxyphenyl diferrocenyl phosphine (cat. 2), 2-methoxynaphtyl diferrocenyl phosphine (cat. 3), 1,1’-bis(diphenylphosphino) ferrocene (cat. 4), phenyl diferrocenyl phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prepare extreme This study examined investigation of catalytic activity of aryl-ferrocenyl-phosphine (2-methoxyphenyl diferrocenyl phosphine (cat. 1), 2-tert-butyloxyphenyl diferrocenyl phosphine (cat. 2), 2-methoxynaphtyl diferrocenyl phosphine (cat. 3), 1,1’-bis(diphenylphosphino) ferrocene (cat. 4), phenyl diferrocenyl phosphine (cat. 5)) ligands with palladium salts as precursors in Suzuki–Miyaura reaction. Suzuki–Miyaura reaction is one of the important cross-coupling reactions and extremely powerful in forming C–C bonds. Aryl-ferrocenyl-phosphine ligands confer unprecedented activity for these processes, allowing reactions to be performed at low catalyst levels, to prepare extremely hindered biaryls and to be carried out, in general, also for reactions of aryl chlorides by temperature 100 ºC and pressure 1 atm. Sterically demanding and strongly Lewis-basic ferrocene-based phosphines are water- and oxygen-resistant. The Suzuki–Miyaura reaction is also an important reaction in the ground and fine organic synthesis, in the production of drugs and intermediates. To analyze the conversion of halogen aryl compounds the <sup>1</sup>H NMR spectroscopy was used. The advantage of Suzuki–Miyaura reaction in comparison with other cross-coupling reactions (Kumada-, Heck-, Heck-Carbonylation-, Murahashi-, Sonogashira-, Negishi-, Stille-reaktion, etc.) is in the usage of low toxic, water- and oxygen-insensitive thermostable organoboron compounds. As boronic acid was used phenylboronic acid and as weak base – potassium phosphate. Catalyst, precursor and weak base were dissolved in toluene. All reactions were performed under an atmosphere of nitrogen or argon. The catalytic cycle of Suzuki–Miyaura reaction typically includes three main steps: oxidative addition of the haloaromatic to catalytic active palladium (0) species, transmetalation, and reductive elimination of the product under back formation of catalytically active species. All used catalysts showed good activity with aryl bromides and weak activity with aryl chlorides.</p>


2007 ◽  
Vol 61 (3) ◽  
Author(s):  
A. Wolfson ◽  
C. Dlugy

AbstractThe Heck coupling of halobenzenes with various alkenes and the Suzuki cross coupling of halobenzenes with phenylboronic acid were successfully performed in glycerol as the reaction solvent using homogeneous and heterogeneous palladium catalysts. Glycerol is a renewable and recyclable green solvent that is able to dissolve organic substrates, inorganic bases, and palladium complexes, and that allows easy isolation of the reaction product by simple extraction with glycerol-immiscible solvents such as diethyl ether, hexane, and dichloromethane.


2005 ◽  
Vol 690 (2) ◽  
pp. 477-481 ◽  
Author(s):  
Rhett C. Smith ◽  
Christina R. Bodner ◽  
Meredith J. Earl ◽  
Nathaniel C. Sears ◽  
Nicholas E. Hill ◽  
...  

2021 ◽  
Vol 25 ◽  
Author(s):  
Réka Henyecz ◽  
György Keglevich

Abstract: Microwave (MW)-assistance may be a powerful tool also in the Hirao P–C coupling reactions of vinyl/aryl halides with dialkyl phosphites in the presence of Pd-catalysts/P-ligands elaborated forty years ago. This review surveys the development of this reaction by showing the expansion of the reagents and catalysts, as well as the information accumulated. The stress was laid on the “green” aspects, the simplification of the catalyst systems, and the reliable mechanistic details in order to be able to establish the optimum conditions. The best protocol involves the use of some excess of the >P(O)H reagent to ensure the PdII→Pd0 reduction and, via its trivalent tautomeric form (>POH) also the P-ligand. The overall rate is the result of two factors, the activity of the catalyst complex formed, and the reactivity of the reactants in the P–C coupling reactions. Both components are influenced by the nature of the aryl substituents in Ar2P(O)H. NiII salts may also be used as the catalyst precursor, however, despite the PdII→Pd0→PdII route, in this case, a NiII→NiIV→NiII sequence was proved.


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