A New Oxidative Addition of Ruthenium(0) into an Aryl Halide Bond and Subsequent Intermolecular C−H Insertion

An unprecedented oxidative insertion of the activated ruthenium complex “Ru(CO)(PPh3)2” into aryl halide bonds enables a novel preparation of stable five-coordinate 16-electron d(6) σ-aryl-Ru(II) complex Ru(CO)(p-C6H4Me)Br(PPh3)2, which has been characterized by NMR, IR, elemental analysis, and X-ray crystallography. These novel five-coordinate Ru(II) complexes were investigated as potential intermediates in the ortho-arylation of aryl ketones (α-tetralone) through C−H activation and resulted in the formation of Ru(CO)(η1-C, κ1-O, α-tetralone)X(PPh3)2 and toluene (X = Br or I).