59115-49-0Relevant articles and documents
C(sp2)-C(sp2) cross coupling reaction catalyzed by a water-stable palladium complex supported onto nanomagnetite particles
Azadbakht, Tahereh,Zolfigol, Mohammad Ali,Azadbakht, Reza,Khakyzadeh, Vahid,Perrin, David M.
, p. 439 - 444 (2015)
A water-stable palladium complex supported onto nanomagnetite particles was prepared and characterized. The nanocatalyst showed excellent reusability and activity in aqueous phase processes including the C(sp2)-C(sp2) cross coupling reactions. The advantages of the protocol are its generality, high yields, short reaction time, a cleaner reaction profile, and simplicity.
Impact of Solvent and Their Contaminants on Pd/C Catalyzed Suzuki-Miyaura Cross-Coupling Reactions
de Lambert de Boisjan, Alexandre,Allemann, Christophe,Fadini, Luca
, (2021/05/17)
The aim of this work was to understand if solvent contaminants can interfere in Suzuki’s cross-coupling reactions and if it can explain the lack of robustness in industrial processes. For this purpose, several parameters were tested on the industrial model reaction between 2-bromonaphthalene and phenylboronic acid catalyzed by Pd/C. Best results were obtained using THF as solvent. Traces of the precursors of the used solvents, such as 2,3-dihydrofurane or maleic anhydride (100–300 ppm related to the solvent) strongly poisoned the reaction, decreasing the conversion significantly. This means that to ensure robust production, solvent quality must be analyzed at the ppm level. Fortunately, addition of triphenylphosphine can circumvent the catalyst poisoning.
The Anionic Pathway in the Nickel-Catalysed Cross-Coupling of Aryl Ethers
Borys, Andryj M.,Hevia, Eva
supporting information, p. 24659 - 24667 (2021/10/20)
The Ni-catalysed cross-coupling of aryl ethers is a powerful method to forge new C?C and C?heteroatom bonds. However, the inert C(sp2)?O bond means that a canonical mechanism that relies on the oxidative addition of the aryl ether to a Ni0 centre is thermodynamically and kinetically unfavourable, which suggests that alternative mechanisms may be involved. Here, we provide spectroscopic and structural insights into the anionic pathway, which relies on the formation of electron-rich hetero-bimetallic nickelates by adding organometallic nucleophiles to a Ni0 centre. Assessing the rich co-complexation chemistry between Ni(COD)2 and PhLi has led to the structures and solution-state chemistry of a diverse family of catalytically competent lithium nickelates being unveiled. In addition, we demonstrate dramatic solvent and donor effects, which suggest that the cooperative activation of the aryl ether substrate by Ni0-ate complexes plays a key role in the catalytic cycle.
Cobalt-Catalyzed Coupling of Aryl Chlorides with Aryl Boron Esters Activated by Alkoxides
Tailor, Sanita B.,Manzotti, Mattia,Smith, Gavin J.,Davis, Sean A.,Bedford, Robin B.
, p. 3856 - 3866 (2021/04/07)
The cobalt-catalyzed Suzuki biaryl cross-coupling of aryl chloride substrates with aryl boron reagents, activated with more commonly used bases, remained a significant unmet challenge in the race to replace platinum group metal catalysts with Earth-abundant metal alternatives. We now show that this highly desirable process can be realized using alkoxide bases, provided the right counterion is employed, strict stoichiometric control of the base is maintained with respect to the aryl boron reagent, and the correct boron ester is selected. Potassium tert-butoxide works well, but any excess of the base first inhibits and then poisons the catalyst. Lithium tert-butoxide performs very poorly, while even catalytic amounts of lithium additives also poison the catalyst. Meanwhile, a neopentane diol-based boron ester is required for best performance. As well as delivering this sought-after transformation, we have undertaken detailed mechanistic and computational investigations to probe the possible mechanism of the reaction and help explain the unexpected experimental observations.