2024-03-29T08:46:48Zhttps://uvadoc.uva.es/oai/requestoai:uvadoc.uva.es:10324/490292021-11-17T12:52:34Zcom_10324_28542com_10324_952com_10324_894col_10324_28543
Villalba de Pando, Francisco
Albéniz Jiménez, Ana Carmen
2021-10-13T09:31:47Z
2021-10-13T09:31:47Z
2021
Advanced Synthesis & Catalysis, 2021, vol. 363, p. 1-11
1615-4150
https://uvadoc.uva.es/handle/10324/49029
10.1002/adsc.202100677
1
11
Advanced Synthesis & Catalysis
363
1615-4169
The pyridone fragment in the ligand [2, 2’-bipyridin]-6(1H)-one (bipy-6-OH) enables the oxidative Heck reaction of simple arenes with oxygen as the sole oxidant and no redox mediator. Arenes with either electron-donating or electron-withdrawing groups can be functionalized in this way. Experimental data on the reaction with toluene as the model arene shows that the C−H activation step is turnover limiting and that the ligand structure is crucial to facilitate the reaction, which supports the involvement of the pyridone fragment in the C−H activation step. In the case of fluoroarenes, the alkenylation of mono and 1,2-difluoro benzenes requires the presence of bipy-6-OH. In contrast, this ligand is detrimental for the alkenylation of 1,3-difluoro, tri, tetra and pentafluoro benzenes which can be carried out using just [Pd(OAc)2]. This correlates with the acidity of the fluoroarenes, the most acidic undergoing easier C−H activation so other steps of the reaction such as the coordination-insertion of the olefin become kinetically important for polyfluorinated arenes. The use of just a catalytic amount of sodium molybdate as a base proved to be optimal in all these reactions.
eng
info:eu-repo/semantics/openAccess
http://creativecommons.org/licenses/by-nc-nd/4.0/
© 2021 The Authors
Attribution-NonCommercial-NoDerivatives 4.0 Internacional
Non‐chelate‐assisted palladium‐catalyzed aerobic oxidative heck reaction of fluorobenzenes and other arenes: When does the C−H activation need help?
info:eu-repo/semantics/article