Ru-Catalyzed C-H Arylation of Fluoroarenes with Aryl Halides was written by Simonetti, Marco;Perry, Gregory J. P.;Cambeiro, Xacobe C.;Julia-Hernandez, Francisco;Arokianathar, Jude N.;Larrosa, Igor. And the article was included in Journal of the American Chemical Society in 2016.Product Details of 4783-68-0 This article mentions the following:
Although the ruthenium-catalyzed C-H arylation of arenes bearing directing groups with haloarenes is well-known, this process has never been achieved in the absence of directing groups. We report the first example of such a process and show that unexpectedly the reaction only takes place in the presence of catalytic amounts of a benzoic acid. Furthermore, contrary to other transition metals, the arylation site selectivity is governed by both electronic and steric factors. Stoichiometric and NMR mechanistic studies support a catalytic cycle that involves a well-defined η6-arene-ligand-free Ru(II) catalyst. Indeed, upon initial pivalate-assisted C-H activation, the aryl-Ru(II) intermediate generated is able to react with an aryl bromide coupling partner only in the presence of a benzoate additive. In contrast, directing-group-containing substrates (such as 2-phenylpyridine) do not require a benzoate additive. Deuterium labeling and kinetic isotope effect experiments indicate that C-H activation is both reversible and kinetically significant. Computational studies support a concerted metalation-deprotonation (CMD)-type ruthenation mode and shed light on the unusual arylation regioselectivity. In the experiment, the researchers used many compounds, for example, 2-Phenoxypyridine (cas: 4783-68-0Product Details of 4783-68-0).
2-Phenoxypyridine (cas: 4783-68-0) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Product Details of 4783-68-0