Activation Of N-aromatic ?-H Coupling Reaction With A Halogenated Aromatic Hydrocarbons

Functionalized aryl chlorides are more economically attractive but usually much more difficult as substrates in metal-mediated couplings than the corresponding bromides and iodides. It was found that ruthenium catalyzed the ortho-position C-H bond of the aromatic hydrocarbon, and the mono- and diarylated coupling products were obtained. Chlorination, bromination and iodinated aromatics could react, but the reactivity was different.Formation of C-C bond is one of the most fundamental transformation in organic chemistry, it has been reported that catalyzed C-C bond formation between ortho-position C-H bond and halogenated aromatic compound catalyzed by ruthenium,but the currently used electrophilic reagents are mainly brominated and iodinated aromatic compounds, the use of less active chlorinated aromatic hydrocarbons and electron-rich phosphine ligands bearing large stubstituting groups to control the activation of C-H bond at the only specific positions was very few reported. In this paper, the coupling reaction of phosphorus ligand-ruthenium-catalyzed nitrogen-containing groups to ortho-C-H bonds and chlorinated aromatic or heterocyclic chlorinated aromatics was studied.Herein, we focused on the types of reactive ligands and found that when the phosphorus-containing compounds with large groups were used as ligands, a good yield was obtained, which is a kind of selective ligand. The optimum reaction conditions were obtained through a large number of experimental optimization: the commercially available dimer ruthenium compound [RuCl2(p-cymene)2] dimer was used as the catalyst (the amount of catalyst was 1 mol%), NMP as the solvent, having large substituting group and electron-rich phosphine compound as ligand (ligand dosage of 2 mol%), potassium carbonate as base, chlorinated aromatic hydrocarbon as a substrate for coupling reaction. The chlorinated aromatic hydrocarbons or heterocyclic chlorinated hydrocarbons with low activity were selected as the substrate,a series of new compounds were obtained, and the yield of the products was about 80%. Moreover,arenes having divers directing groups were examined by this methodolgy, and a series of new products were obtained in moderate to good yield. At the same time, the continuous reaction was carried out by feeding two types arylchlorides, to afford sequential double arylated products.