1346939-26-1Relevant articles and documents
Nickel versus Palladium in Cross-Coupling Catalysis: On the Role of Substrate Coordination to Zerovalent Metal Complexes
Burton, Paul M.,Cooper, Alasdair K.,Nelson, David J.
, p. 565 - 573 (2020/02/13)
A detailed comparison of the effect of coordinating functional groups on the performance of Suzuki-Miyaura reactions catalysed by nickel and palladium is reported, using competition experiments, robustness screening, and density functional theory calculations. Nickel can interact with a variety of functional groups, which manifests as selectivity in competitive cross-coupling reactions. The presence of these functional groups on exogenous additives has effects on cross-coupling reactions that range from a slight improvement in yield to the complete cessation of the reaction. In contrast, palladium does not interact sufficiently strongly with these functional groups to induce selectivity in cross-coupling reactions; the selectivity of palladium-catalysed cross-coupling reactions is predominantly governed by aryl halide electronic properties.
Nickel-catalyzed Suzuki-Miyaura reaction of aryl fluorides
Tobisu, Mamoru,Xu, Tian,Shimasaki, Toshiaki,Chatani, Naoto
supporting information; experimental part, p. 19505 - 19511 (2012/01/31)
Two protocols for the nickel-catalyzed cross-coupling of aryl fluorides with aryl boronic esters have been developed. The first employs metal fluoride cocatalysts, such as ZrF4 and TiF4, which enable Suzuki-Miyaura reactions of aryl fluorides bearing electron-withdrawing (ketones, esters, and CF3), aryl and alkenyl groups as well as those comprising fused aromatic rings, such as fluoronaphthalenes and fluoroquinolines. The second protocol employs aryl fluorides bearing ortho-directing groups, which facilitate the difficult C-F bond activation process via cyclometalation. N-heterocycles, such as pyridines, quinolines, pyrazoles, and oxazolines, can successfully promote cross-coupling with an array of organoboronic esters. A study into the substituent effects with respect to both coupling components has provided fundamental insights into the mechanism of the nickel-catalyzed cross-coupling of aryl fluorides.
